Spherical law of cosines

Percentage Accurate: 73.3% → 94.2%
Time: 47.7s
Alternatives: 29
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \end{array} \]
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (*
  (acos
   (+
    (* (sin phi1) (sin phi2))
    (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))
  R))
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	return acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * R;
}
real(8) function code(r, lambda1, lambda2, phi1, phi2)
    real(8), intent (in) :: r
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: lambda2
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    code = acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * r
end function
public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	return Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos((lambda1 - lambda2))))) * R;
}
def code(R, lambda1, lambda2, phi1, phi2):
	return math.acos(((math.sin(phi1) * math.sin(phi2)) + ((math.cos(phi1) * math.cos(phi2)) * math.cos((lambda1 - lambda2))))) * R
function code(R, lambda1, lambda2, phi1, phi2)
	return Float64(acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))) * R)
end
function tmp = code(R, lambda1, lambda2, phi1, phi2)
	tmp = acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * R;
end
code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * R), $MachinePrecision]
\begin{array}{l}

\\
\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 29 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 73.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \end{array} \]
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (*
  (acos
   (+
    (* (sin phi1) (sin phi2))
    (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))
  R))
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	return acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * R;
}
real(8) function code(r, lambda1, lambda2, phi1, phi2)
    real(8), intent (in) :: r
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: lambda2
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    code = acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * r
end function
public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	return Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos((lambda1 - lambda2))))) * R;
}
def code(R, lambda1, lambda2, phi1, phi2):
	return math.acos(((math.sin(phi1) * math.sin(phi2)) + ((math.cos(phi1) * math.cos(phi2)) * math.cos((lambda1 - lambda2))))) * R
function code(R, lambda1, lambda2, phi1, phi2)
	return Float64(acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))) * R)
end
function tmp = code(R, lambda1, lambda2, phi1, phi2)
	tmp = acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) * R;
end
code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * R), $MachinePrecision]
\begin{array}{l}

\\
\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R
\end{array}

Alternative 1: 94.2% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \phi_1 \cdot \cos \phi_2\\ \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, t_0 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \mathsf{log1p}\left(\mathsf{expm1}\left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\right) \cdot R\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (let* ((t_0 (* (cos phi1) (cos phi2))))
   (if (<= (+ (* (sin phi1) (sin phi2)) (* t_0 (cos (- lambda1 lambda2)))) 1.0)
     (*
      (acos
       (fma
        (sin phi1)
        (sin phi2)
        (*
         t_0
         (fma
          (cos lambda2)
          (cos lambda1)
          (log1p (expm1 (* (sin lambda1) (sin lambda2))))))))
      R)
     (* R (- lambda2 lambda1)))))
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double t_0 = cos(phi1) * cos(phi2);
	double tmp;
	if (((sin(phi1) * sin(phi2)) + (t_0 * cos((lambda1 - lambda2)))) <= 1.0) {
		tmp = acos(fma(sin(phi1), sin(phi2), (t_0 * fma(cos(lambda2), cos(lambda1), log1p(expm1((sin(lambda1) * sin(lambda2)))))))) * R;
	} else {
		tmp = R * (lambda2 - lambda1);
	}
	return tmp;
}
function code(R, lambda1, lambda2, phi1, phi2)
	t_0 = Float64(cos(phi1) * cos(phi2))
	tmp = 0.0
	if (Float64(Float64(sin(phi1) * sin(phi2)) + Float64(t_0 * cos(Float64(lambda1 - lambda2)))) <= 1.0)
		tmp = Float64(acos(fma(sin(phi1), sin(phi2), Float64(t_0 * fma(cos(lambda2), cos(lambda1), log1p(expm1(Float64(sin(lambda1) * sin(lambda2)))))))) * R);
	else
		tmp = Float64(R * Float64(lambda2 - lambda1));
	end
	return tmp
end
code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(t$95$0 * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0], N[(N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(t$95$0 * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[Log[1 + N[(Exp[N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]] - 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * R), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \cos \phi_1 \cdot \cos \phi_2\\
\mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\
\;\;\;\;\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, t_0 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \mathsf{log1p}\left(\mathsf{expm1}\left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\right) \cdot R\\

\mathbf{else}:\\
\;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))) < 1

    1. Initial program 71.6%

      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
    2. Simplified71.7%

      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
    3. Add Preprocessing
    4. Step-by-step derivation
      1. cos-diff94.4%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
      2. distribute-lft-in94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
    5. Applied egg-rr94.5%

      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
    6. Step-by-step derivation
      1. distribute-lft-out94.4%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
      2. *-commutative94.4%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
      3. fma-udef94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
      4. *-commutative94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
    7. Simplified94.5%

      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
    8. Taylor expanded in phi1 around 0 94.5%

      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)} \cdot R \]
    9. Step-by-step derivation
      1. associate-*r*94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
    10. Simplified94.5%

      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)} \cdot R \]
    11. Step-by-step derivation
      1. log1p-expm1-u94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right)\right) \cdot R \]
    12. Applied egg-rr94.5%

      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right)\right) \cdot R \]

    if 1 < (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))

    1. Initial program 71.6%

      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
    2. Step-by-step derivation
      1. Simplified71.6%

        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
      2. Add Preprocessing
      3. Taylor expanded in phi2 around 0 41.8%

        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
      4. Taylor expanded in phi1 around 0 24.2%

        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
      5. Taylor expanded in lambda2 around 0 4.3%

        \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
      6. Step-by-step derivation
        1. neg-mul-14.3%

          \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
        2. sub-neg4.3%

          \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
      7. Simplified4.3%

        \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification94.5%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \mathsf{log1p}\left(\mathsf{expm1}\left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\right) \cdot R\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 2: 94.2% accurate, 0.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
    (FPCore (R lambda1 lambda2 phi1 phi2)
     :precision binary64
     (if (<=
          (+
           (* (sin phi1) (sin phi2))
           (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))
          1.0)
       (*
        R
        (acos
         (fma
          (sin phi1)
          (sin phi2)
          (*
           (cos phi1)
           (*
            (cos phi2)
            (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))))
       (* R (- lambda2 lambda1))))
    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
    	double tmp;
    	if (((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))) <= 1.0) {
    		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * (cos(phi2) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))))));
    	} else {
    		tmp = R * (lambda2 - lambda1);
    	}
    	return tmp;
    }
    
    function code(R, lambda1, lambda2, phi1, phi2)
    	tmp = 0.0
    	if (Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2)))) <= 1.0)
    		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * Float64(cos(phi2) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))))));
    	else
    		tmp = Float64(R * Float64(lambda2 - lambda1));
    	end
    	return tmp
    end
    
    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\
    \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))) < 1

      1. Initial program 71.6%

        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
      2. Simplified71.7%

        \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
      3. Add Preprocessing
      4. Step-by-step derivation
        1. cos-diff94.4%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
        2. distribute-lft-in94.5%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
      5. Applied egg-rr94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
      6. Step-by-step derivation
        1. distribute-lft-out94.4%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
        2. *-commutative94.4%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
        3. fma-udef94.5%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
        4. *-commutative94.5%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
      7. Simplified94.5%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]

      if 1 < (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))

      1. Initial program 71.6%

        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
      2. Step-by-step derivation
        1. Simplified71.6%

          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
        2. Add Preprocessing
        3. Taylor expanded in phi2 around 0 41.8%

          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
        4. Taylor expanded in phi1 around 0 24.2%

          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
        5. Taylor expanded in lambda2 around 0 4.3%

          \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
        6. Step-by-step derivation
          1. neg-mul-14.3%

            \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
          2. sub-neg4.3%

            \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
        7. Simplified4.3%

          \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification94.5%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 3: 94.2% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \phi_1 \cdot \cos \phi_2\\ \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, t_0 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
      (FPCore (R lambda1 lambda2 phi1 phi2)
       :precision binary64
       (let* ((t_0 (* (cos phi1) (cos phi2))))
         (if (<= (+ (* (sin phi1) (sin phi2)) (* t_0 (cos (- lambda1 lambda2)))) 1.0)
           (*
            R
            (acos
             (fma
              (sin phi1)
              (sin phi2)
              (*
               t_0
               (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2)))))))
           (* R (- lambda2 lambda1)))))
      double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
      	double t_0 = cos(phi1) * cos(phi2);
      	double tmp;
      	if (((sin(phi1) * sin(phi2)) + (t_0 * cos((lambda1 - lambda2)))) <= 1.0) {
      		tmp = R * acos(fma(sin(phi1), sin(phi2), (t_0 * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2))))));
      	} else {
      		tmp = R * (lambda2 - lambda1);
      	}
      	return tmp;
      }
      
      function code(R, lambda1, lambda2, phi1, phi2)
      	t_0 = Float64(cos(phi1) * cos(phi2))
      	tmp = 0.0
      	if (Float64(Float64(sin(phi1) * sin(phi2)) + Float64(t_0 * cos(Float64(lambda1 - lambda2)))) <= 1.0)
      		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(t_0 * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2)))))));
      	else
      		tmp = Float64(R * Float64(lambda2 - lambda1));
      	end
      	return tmp
      end
      
      code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(t$95$0 * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(t$95$0 * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \cos \phi_1 \cdot \cos \phi_2\\
      \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\
      \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, t_0 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))) < 1

        1. Initial program 71.6%

          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
        2. Simplified71.7%

          \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
        3. Add Preprocessing
        4. Step-by-step derivation
          1. cos-diff94.4%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
          2. distribute-lft-in94.5%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
        5. Applied egg-rr94.5%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
        6. Step-by-step derivation
          1. distribute-lft-out94.4%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
          2. *-commutative94.4%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
          3. fma-udef94.5%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
          4. *-commutative94.5%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
        7. Simplified94.5%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
        8. Taylor expanded in phi1 around 0 94.5%

          \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)} \cdot R \]
        9. Step-by-step derivation
          1. associate-*r*94.5%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
        10. Simplified94.5%

          \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)} \cdot R \]

        if 1 < (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))

        1. Initial program 71.6%

          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
        2. Step-by-step derivation
          1. Simplified71.6%

            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
          2. Add Preprocessing
          3. Taylor expanded in phi2 around 0 41.8%

            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
          4. Taylor expanded in phi1 around 0 24.2%

            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
          5. Taylor expanded in lambda2 around 0 4.3%

            \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
          6. Step-by-step derivation
            1. neg-mul-14.3%

              \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
            2. sub-neg4.3%

              \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
          7. Simplified4.3%

            \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification94.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \]
        5. Add Preprocessing

        Alternative 4: 94.2% accurate, 0.4× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ t_1 := \cos \phi_1 \cdot \cos \phi_2\\ \mathbf{if}\;t_0 + t_1 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t_1, \sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1, t_0\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
        (FPCore (R lambda1 lambda2 phi1 phi2)
         :precision binary64
         (let* ((t_0 (* (sin phi1) (sin phi2))) (t_1 (* (cos phi1) (cos phi2))))
           (if (<= (+ t_0 (* t_1 (cos (- lambda1 lambda2)))) 1.0)
             (*
              R
              (acos
               (fma
                t_1
                (+ (* (sin lambda1) (sin lambda2)) (* (cos lambda2) (cos lambda1)))
                t_0)))
             (* R (- lambda2 lambda1)))))
        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
        	double t_0 = sin(phi1) * sin(phi2);
        	double t_1 = cos(phi1) * cos(phi2);
        	double tmp;
        	if ((t_0 + (t_1 * cos((lambda1 - lambda2)))) <= 1.0) {
        		tmp = R * acos(fma(t_1, ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1))), t_0));
        	} else {
        		tmp = R * (lambda2 - lambda1);
        	}
        	return tmp;
        }
        
        function code(R, lambda1, lambda2, phi1, phi2)
        	t_0 = Float64(sin(phi1) * sin(phi2))
        	t_1 = Float64(cos(phi1) * cos(phi2))
        	tmp = 0.0
        	if (Float64(t_0 + Float64(t_1 * cos(Float64(lambda1 - lambda2)))) <= 1.0)
        		tmp = Float64(R * acos(fma(t_1, Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1))), t_0)));
        	else
        		tmp = Float64(R * Float64(lambda2 - lambda1));
        	end
        	return tmp
        end
        
        code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(t$95$0 + N[(t$95$1 * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0], N[(R * N[ArcCos[N[(t$95$1 * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_0 := \sin \phi_1 \cdot \sin \phi_2\\
        t_1 := \cos \phi_1 \cdot \cos \phi_2\\
        \mathbf{if}\;t_0 + t_1 \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\
        \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t_1, \sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1, t_0\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))) < 1

          1. Initial program 71.6%

            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
          2. Step-by-step derivation
            1. Simplified71.6%

              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. cos-diff50.2%

                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
              2. +-commutative50.2%

                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
              3. *-commutative50.2%

                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
              4. *-commutative50.2%

                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
            4. Applied egg-rr94.4%

              \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_1 \cdot \cos \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]

            if 1 < (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))

            1. Initial program 71.6%

              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
            2. Step-by-step derivation
              1. Simplified71.6%

                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
              2. Add Preprocessing
              3. Taylor expanded in phi2 around 0 41.8%

                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
              4. Taylor expanded in phi1 around 0 24.2%

                \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
              5. Taylor expanded in lambda2 around 0 4.3%

                \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
              6. Step-by-step derivation
                1. neg-mul-14.3%

                  \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
                2. sub-neg4.3%

                  \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
              7. Simplified4.3%

                \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification94.4%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) \leq 1:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \]
            5. Add Preprocessing

            Alternative 5: 83.5% accurate, 0.6× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \end{array} \end{array} \]
            (FPCore (R lambda1 lambda2 phi1 phi2)
             :precision binary64
             (if (or (<= phi1 -8e-9) (not (<= phi1 7.2e-18)))
               (*
                R
                (-
                 (* PI 0.5)
                 (cbrt
                  (pow
                   (asin
                    (fma
                     (cos phi1)
                     (* (cos phi2) (cos (- lambda2 lambda1)))
                     (* (sin phi1) (sin phi2))))
                   3.0))))
               (*
                R
                (acos
                 (fma
                  (sin phi1)
                  (sin phi2)
                  (*
                   (cos phi2)
                   (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2)))))))))
            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
            	double tmp;
            	if ((phi1 <= -8e-9) || !(phi1 <= 7.2e-18)) {
            		tmp = R * ((((double) M_PI) * 0.5) - cbrt(pow(asin(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), (sin(phi1) * sin(phi2)))), 3.0)));
            	} else {
            		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi2) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2))))));
            	}
            	return tmp;
            }
            
            function code(R, lambda1, lambda2, phi1, phi2)
            	tmp = 0.0
            	if ((phi1 <= -8e-9) || !(phi1 <= 7.2e-18))
            		tmp = Float64(R * Float64(Float64(pi * 0.5) - cbrt((asin(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), Float64(sin(phi1) * sin(phi2)))) ^ 3.0))));
            	else
            		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi2) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2)))))));
            	end
            	return tmp
            end
            
            code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi1, -8e-9], N[Not[LessEqual[phi1, 7.2e-18]], $MachinePrecision]], N[(R * N[(N[(Pi * 0.5), $MachinePrecision] - N[Power[N[Power[N[ArcSin[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 3.0], $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi2], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\
            \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if phi1 < -8.0000000000000005e-9 or 7.20000000000000021e-18 < phi1

              1. Initial program 74.8%

                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
              2. Step-by-step derivation
                1. Simplified74.8%

                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. cos-diff98.7%

                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                  2. *-commutative98.7%

                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                  3. *-commutative98.7%

                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                  4. cos-diff74.8%

                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                  5. fma-def74.8%

                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]
                  6. +-commutative74.8%

                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} \]
                  7. acos-asin74.9%

                    \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]
                  8. sub-neg74.9%

                    \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)} \]
                  9. div-inv74.9%

                    \[\leadsto R \cdot \left(\color{blue}{\pi \cdot \frac{1}{2}} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                  10. metadata-eval74.9%

                    \[\leadsto R \cdot \left(\pi \cdot \color{blue}{0.5} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                  11. +-commutative74.9%

                    \[\leadsto R \cdot \left(\pi \cdot 0.5 + \left(-\sin^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}\right)\right) \]
                4. Applied egg-rr74.9%

                  \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 + \left(-\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\right)} \]
                5. Step-by-step derivation
                  1. sub-neg74.9%

                    \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                6. Simplified74.9%

                  \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                7. Step-by-step derivation
                  1. add-cbrt-cube75.0%

                    \[\leadsto R \cdot \left(\pi \cdot 0.5 - \color{blue}{\sqrt[3]{\left(\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right) \cdot \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}}\right) \]
                  2. pow375.0%

                    \[\leadsto R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{\color{blue}{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}}\right) \]
                8. Applied egg-rr75.0%

                  \[\leadsto R \cdot \left(\pi \cdot 0.5 - \color{blue}{\sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}}\right) \]

                if -8.0000000000000005e-9 < phi1 < 7.20000000000000021e-18

                1. Initial program 66.8%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Simplified66.8%

                  \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                3. Add Preprocessing
                4. Step-by-step derivation
                  1. cos-diff88.0%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                  2. distribute-lft-in88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                5. Applied egg-rr88.1%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                6. Step-by-step derivation
                  1. distribute-lft-out88.0%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                  2. *-commutative88.0%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
                  3. fma-udef88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                  4. *-commutative88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
                7. Simplified88.1%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
                8. Taylor expanded in phi1 around 0 88.1%

                  \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)} \cdot R \]
                9. Step-by-step derivation
                  1. associate-*r*88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                10. Simplified88.1%

                  \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)} \cdot R \]
                11. Taylor expanded in phi1 around 0 88.0%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                12. Step-by-step derivation
                  1. *-commutative88.0%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right) \cdot R \]
                  2. fma-udef88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                13. Simplified88.1%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
              3. Recombined 2 regimes into one program.
              4. Final simplification80.2%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \end{array} \]
              5. Add Preprocessing

              Alternative 6: 83.5% accurate, 0.7× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \end{array} \end{array} \]
              (FPCore (R lambda1 lambda2 phi1 phi2)
               :precision binary64
               (if (or (<= phi1 -8e-9) (not (<= phi1 7.2e-18)))
                 (*
                  R
                  (-
                   (* PI 0.5)
                   (cbrt
                    (pow
                     (asin
                      (fma
                       (cos phi1)
                       (* (cos phi2) (cos (- lambda2 lambda1)))
                       (* (sin phi1) (sin phi2))))
                     3.0))))
                 (*
                  R
                  (acos
                   (fma
                    (sin phi1)
                    (sin phi2)
                    (*
                     (cos phi2)
                     (+
                      (* (sin lambda1) (sin lambda2))
                      (* (cos lambda2) (cos lambda1)))))))))
              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
              	double tmp;
              	if ((phi1 <= -8e-9) || !(phi1 <= 7.2e-18)) {
              		tmp = R * ((((double) M_PI) * 0.5) - cbrt(pow(asin(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), (sin(phi1) * sin(phi2)))), 3.0)));
              	} else {
              		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi2) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1))))));
              	}
              	return tmp;
              }
              
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if ((phi1 <= -8e-9) || !(phi1 <= 7.2e-18))
              		tmp = Float64(R * Float64(Float64(pi * 0.5) - cbrt((asin(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), Float64(sin(phi1) * sin(phi2)))) ^ 3.0))));
              	else
              		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi2) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1)))))));
              	end
              	return tmp
              end
              
              code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi1, -8e-9], N[Not[LessEqual[phi1, 7.2e-18]], $MachinePrecision]], N[(R * N[(N[(Pi * 0.5), $MachinePrecision] - N[Power[N[Power[N[ArcSin[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 3.0], $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi2], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\
              \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -8.0000000000000005e-9 or 7.20000000000000021e-18 < phi1

                1. Initial program 74.8%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Step-by-step derivation
                  1. Simplified74.8%

                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. cos-diff98.7%

                      \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                    2. *-commutative98.7%

                      \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                    3. *-commutative98.7%

                      \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                    4. cos-diff74.8%

                      \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                    5. fma-def74.8%

                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]
                    6. +-commutative74.8%

                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} \]
                    7. acos-asin74.9%

                      \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]
                    8. sub-neg74.9%

                      \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)} \]
                    9. div-inv74.9%

                      \[\leadsto R \cdot \left(\color{blue}{\pi \cdot \frac{1}{2}} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                    10. metadata-eval74.9%

                      \[\leadsto R \cdot \left(\pi \cdot \color{blue}{0.5} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                    11. +-commutative74.9%

                      \[\leadsto R \cdot \left(\pi \cdot 0.5 + \left(-\sin^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}\right)\right) \]
                  4. Applied egg-rr74.9%

                    \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 + \left(-\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\right)} \]
                  5. Step-by-step derivation
                    1. sub-neg74.9%

                      \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                  6. Simplified74.9%

                    \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                  7. Step-by-step derivation
                    1. add-cbrt-cube75.0%

                      \[\leadsto R \cdot \left(\pi \cdot 0.5 - \color{blue}{\sqrt[3]{\left(\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right) \cdot \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}}\right) \]
                    2. pow375.0%

                      \[\leadsto R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{\color{blue}{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}}\right) \]
                  8. Applied egg-rr75.0%

                    \[\leadsto R \cdot \left(\pi \cdot 0.5 - \color{blue}{\sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}}\right) \]

                  if -8.0000000000000005e-9 < phi1 < 7.20000000000000021e-18

                  1. Initial program 66.8%

                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                  2. Simplified66.8%

                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                  3. Add Preprocessing
                  4. Step-by-step derivation
                    1. cos-diff88.0%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                    2. distribute-lft-in88.1%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                  5. Applied egg-rr88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                  6. Step-by-step derivation
                    1. distribute-lft-out88.0%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                    2. *-commutative88.0%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
                    3. fma-udef88.1%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                    4. *-commutative88.1%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
                  7. Simplified88.1%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
                  8. Taylor expanded in phi1 around 0 88.1%

                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)} \cdot R \]
                  9. Step-by-step derivation
                    1. associate-*r*88.1%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                  10. Simplified88.1%

                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)} \cdot R \]
                  11. Taylor expanded in phi1 around 0 88.0%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                3. Recombined 2 regimes into one program.
                4. Final simplification80.2%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -8 \cdot 10^{-9} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sqrt[3]{{\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}^{3}}\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \end{array} \]
                5. Add Preprocessing

                Alternative 7: 83.6% accurate, 0.7× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -3.1 \cdot 10^{-7} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \end{array} \end{array} \]
                (FPCore (R lambda1 lambda2 phi1 phi2)
                 :precision binary64
                 (if (or (<= phi1 -3.1e-7) (not (<= phi1 7.2e-18)))
                   (*
                    R
                    (-
                     (* PI 0.5)
                     (asin
                      (fma
                       (cos phi1)
                       (* (cos phi2) (cos (- lambda2 lambda1)))
                       (* (sin phi1) (sin phi2))))))
                   (*
                    R
                    (acos
                     (fma
                      (sin phi1)
                      (sin phi2)
                      (*
                       (cos phi2)
                       (+
                        (* (sin lambda1) (sin lambda2))
                        (* (cos lambda2) (cos lambda1)))))))))
                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                	double tmp;
                	if ((phi1 <= -3.1e-7) || !(phi1 <= 7.2e-18)) {
                		tmp = R * ((((double) M_PI) * 0.5) - asin(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), (sin(phi1) * sin(phi2)))));
                	} else {
                		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi2) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1))))));
                	}
                	return tmp;
                }
                
                function code(R, lambda1, lambda2, phi1, phi2)
                	tmp = 0.0
                	if ((phi1 <= -3.1e-7) || !(phi1 <= 7.2e-18))
                		tmp = Float64(R * Float64(Float64(pi * 0.5) - asin(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), Float64(sin(phi1) * sin(phi2))))));
                	else
                		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi2) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1)))))));
                	end
                	return tmp
                end
                
                code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi1, -3.1e-7], N[Not[LessEqual[phi1, 7.2e-18]], $MachinePrecision]], N[(R * N[(N[(Pi * 0.5), $MachinePrecision] - N[ArcSin[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi2], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;\phi_1 \leq -3.1 \cdot 10^{-7} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\
                \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\\
                
                \mathbf{else}:\\
                \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if phi1 < -3.1e-7 or 7.20000000000000021e-18 < phi1

                  1. Initial program 74.7%

                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                  2. Step-by-step derivation
                    1. Simplified74.7%

                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                    2. Add Preprocessing
                    3. Step-by-step derivation
                      1. cos-diff98.7%

                        \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                      2. *-commutative98.7%

                        \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                      3. *-commutative98.7%

                        \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                      4. cos-diff74.7%

                        \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                      5. fma-def74.7%

                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]
                      6. +-commutative74.7%

                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} \]
                      7. acos-asin74.7%

                        \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]
                      8. sub-neg74.7%

                        \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)} \]
                      9. div-inv74.7%

                        \[\leadsto R \cdot \left(\color{blue}{\pi \cdot \frac{1}{2}} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                      10. metadata-eval74.7%

                        \[\leadsto R \cdot \left(\pi \cdot \color{blue}{0.5} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                      11. +-commutative74.7%

                        \[\leadsto R \cdot \left(\pi \cdot 0.5 + \left(-\sin^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}\right)\right) \]
                    4. Applied egg-rr74.8%

                      \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 + \left(-\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\right)} \]
                    5. Step-by-step derivation
                      1. sub-neg74.8%

                        \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                    6. Simplified74.8%

                      \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]

                    if -3.1e-7 < phi1 < 7.20000000000000021e-18

                    1. Initial program 67.1%

                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                    2. Simplified67.1%

                      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                    3. Add Preprocessing
                    4. Step-by-step derivation
                      1. cos-diff88.1%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                      2. distribute-lft-in88.2%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                    5. Applied egg-rr88.2%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                    6. Step-by-step derivation
                      1. distribute-lft-out88.1%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                      2. *-commutative88.1%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
                      3. fma-udef88.2%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                      4. *-commutative88.2%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
                    7. Simplified88.2%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
                    8. Taylor expanded in phi1 around 0 88.2%

                      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)} \cdot R \]
                    9. Step-by-step derivation
                      1. associate-*r*88.2%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                    10. Simplified88.2%

                      \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)} \cdot R \]
                    11. Taylor expanded in phi1 around 0 88.1%

                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \color{blue}{\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]
                  3. Recombined 2 regimes into one program.
                  4. Final simplification80.2%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -3.1 \cdot 10^{-7} \lor \neg \left(\phi_1 \leq 7.2 \cdot 10^{-18}\right):\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \end{array} \]
                  5. Add Preprocessing

                  Alternative 8: 83.9% accurate, 0.7× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\phi_2 \leq -0.0014:\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), t_0\right)\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), t_0\right)\right)\\ \end{array} \end{array} \]
                  (FPCore (R lambda1 lambda2 phi1 phi2)
                   :precision binary64
                   (let* ((t_0 (* (sin phi1) (sin phi2))))
                     (if (<= phi2 -0.0014)
                       (*
                        R
                        (-
                         (* PI 0.5)
                         (asin (fma (cos phi1) (* (cos phi2) (cos (- lambda2 lambda1))) t_0))))
                       (if (<= phi2 6.6e-5)
                         (*
                          R
                          (acos
                           (fma
                            (sin phi1)
                            (sin phi2)
                            (*
                             (cos phi1)
                             (+
                              (* (sin lambda1) (sin lambda2))
                              (* (cos lambda2) (cos lambda1)))))))
                         (*
                          R
                          (acos
                           (fma (cos phi1) (* (cos phi2) (cos (- lambda1 lambda2))) t_0)))))))
                  double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                  	double t_0 = sin(phi1) * sin(phi2);
                  	double tmp;
                  	if (phi2 <= -0.0014) {
                  		tmp = R * ((((double) M_PI) * 0.5) - asin(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), t_0)));
                  	} else if (phi2 <= 6.6e-5) {
                  		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1))))));
                  	} else {
                  		tmp = R * acos(fma(cos(phi1), (cos(phi2) * cos((lambda1 - lambda2))), t_0));
                  	}
                  	return tmp;
                  }
                  
                  function code(R, lambda1, lambda2, phi1, phi2)
                  	t_0 = Float64(sin(phi1) * sin(phi2))
                  	tmp = 0.0
                  	if (phi2 <= -0.0014)
                  		tmp = Float64(R * Float64(Float64(pi * 0.5) - asin(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), t_0))));
                  	elseif (phi2 <= 6.6e-5)
                  		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1)))))));
                  	else
                  		tmp = Float64(R * acos(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda1 - lambda2))), t_0)));
                  	end
                  	return tmp
                  end
                  
                  code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -0.0014], N[(R * N[(N[(Pi * 0.5), $MachinePrecision] - N[ArcSin[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_0 := \sin \phi_1 \cdot \sin \phi_2\\
                  \mathbf{if}\;\phi_2 \leq -0.0014:\\
                  \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), t_0\right)\right)\right)\\
                  
                  \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                  \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), t_0\right)\right)\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 3 regimes
                  2. if phi2 < -0.00139999999999999999

                    1. Initial program 71.8%

                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                    2. Step-by-step derivation
                      1. Simplified71.8%

                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                      2. Add Preprocessing
                      3. Step-by-step derivation
                        1. cos-diff99.0%

                          \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                        2. *-commutative99.0%

                          \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                        3. *-commutative99.0%

                          \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                        4. cos-diff71.8%

                          \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                        5. fma-def71.8%

                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]
                        6. +-commutative71.8%

                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} \]
                        7. acos-asin71.9%

                          \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]
                        8. sub-neg71.9%

                          \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)} \]
                        9. div-inv71.9%

                          \[\leadsto R \cdot \left(\color{blue}{\pi \cdot \frac{1}{2}} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                        10. metadata-eval71.9%

                          \[\leadsto R \cdot \left(\pi \cdot \color{blue}{0.5} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                        11. +-commutative71.9%

                          \[\leadsto R \cdot \left(\pi \cdot 0.5 + \left(-\sin^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}\right)\right) \]
                      4. Applied egg-rr71.9%

                        \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 + \left(-\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\right)} \]
                      5. Step-by-step derivation
                        1. sub-neg71.9%

                          \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                      6. Simplified71.9%

                        \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]

                      if -0.00139999999999999999 < phi2 < 6.6000000000000005e-5

                      1. Initial program 69.9%

                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                      2. Simplified69.9%

                        \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                      3. Add Preprocessing
                      4. Step-by-step derivation
                        1. cos-diff88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                        2. distribute-lft-in88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                      5. Applied egg-rr88.8%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                      6. Step-by-step derivation
                        1. distribute-lft-out88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                        2. *-commutative88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
                        3. fma-udef88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                        4. *-commutative88.8%

                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
                      7. Simplified88.8%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
                      8. Taylor expanded in phi2 around 0 88.5%

                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right) \cdot R \]

                      if 6.6000000000000005e-5 < phi2

                      1. Initial program 74.1%

                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                      2. Step-by-step derivation
                        1. +-commutative74.1%

                          \[\leadsto \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
                        2. associate-*l*74.1%

                          \[\leadsto \cos^{-1} \left(\color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} + \sin \phi_1 \cdot \sin \phi_2\right) \cdot R \]
                        3. fma-def74.2%

                          \[\leadsto \cos^{-1} \color{blue}{\left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \cdot R \]
                      3. Simplified74.2%

                        \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot R} \]
                      4. Add Preprocessing
                    3. Recombined 3 regimes into one program.
                    4. Final simplification80.0%

                      \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.0014:\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
                    5. Add Preprocessing

                    Alternative 9: 83.6% accurate, 0.9× speedup?

                    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \phi_1 \cdot \cos \phi_2\\ t_1 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t_1 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t_0, \cos \left(\lambda_2 - \lambda_1\right), t_1\right)\right)\\ \end{array} \end{array} \]
                    (FPCore (R lambda1 lambda2 phi1 phi2)
                     :precision binary64
                     (let* ((t_0 (* (cos phi1) (cos phi2))) (t_1 (* (sin phi1) (sin phi2))))
                       (if (<= phi2 -4.2e-16)
                         (* R (acos (+ t_1 (* t_0 (cos (- lambda1 lambda2))))))
                         (if (<= phi2 6.6e-5)
                           (*
                            R
                            (acos
                             (*
                              (cos phi1)
                              (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))
                           (* R (acos (fma t_0 (cos (- lambda2 lambda1)) t_1)))))))
                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                    	double t_0 = cos(phi1) * cos(phi2);
                    	double t_1 = sin(phi1) * sin(phi2);
                    	double tmp;
                    	if (phi2 <= -4.2e-16) {
                    		tmp = R * acos((t_1 + (t_0 * cos((lambda1 - lambda2)))));
                    	} else if (phi2 <= 6.6e-5) {
                    		tmp = R * acos((cos(phi1) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))));
                    	} else {
                    		tmp = R * acos(fma(t_0, cos((lambda2 - lambda1)), t_1));
                    	}
                    	return tmp;
                    }
                    
                    function code(R, lambda1, lambda2, phi1, phi2)
                    	t_0 = Float64(cos(phi1) * cos(phi2))
                    	t_1 = Float64(sin(phi1) * sin(phi2))
                    	tmp = 0.0
                    	if (phi2 <= -4.2e-16)
                    		tmp = Float64(R * acos(Float64(t_1 + Float64(t_0 * cos(Float64(lambda1 - lambda2))))));
                    	elseif (phi2 <= 6.6e-5)
                    		tmp = Float64(R * acos(Float64(cos(phi1) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))));
                    	else
                    		tmp = Float64(R * acos(fma(t_0, cos(Float64(lambda2 - lambda1)), t_1)));
                    	end
                    	return tmp
                    end
                    
                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -4.2e-16], N[(R * N[ArcCos[N[(t$95$1 + N[(t$95$0 * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(t$95$0 * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision] + t$95$1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]
                    
                    \begin{array}{l}
                    
                    \\
                    \begin{array}{l}
                    t_0 := \cos \phi_1 \cdot \cos \phi_2\\
                    t_1 := \sin \phi_1 \cdot \sin \phi_2\\
                    \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\
                    \;\;\;\;R \cdot \cos^{-1} \left(t_1 + t_0 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\
                    
                    \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                    \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                    
                    \mathbf{else}:\\
                    \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t_0, \cos \left(\lambda_2 - \lambda_1\right), t_1\right)\right)\\
                    
                    
                    \end{array}
                    \end{array}
                    
                    Derivation
                    1. Split input into 3 regimes
                    2. if phi2 < -4.2000000000000002e-16

                      1. Initial program 71.9%

                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                      2. Add Preprocessing

                      if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                      1. Initial program 69.8%

                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                      2. Step-by-step derivation
                        1. Simplified69.8%

                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                        2. Add Preprocessing
                        3. Taylor expanded in phi2 around 0 69.8%

                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                        4. Step-by-step derivation
                          1. cos-diff88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                          2. *-commutative88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1\right)\right) \]
                          3. *-commutative88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}\right)\right) \]
                        5. Applied egg-rr88.7%

                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                        6. Step-by-step derivation
                          1. *-commutative88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) \]
                          2. fma-udef88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                          3. *-commutative88.7%

                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right) \]
                        7. Simplified88.7%

                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]

                        if 6.6000000000000005e-5 < phi2

                        1. Initial program 74.1%

                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                        2. Step-by-step derivation
                          1. Simplified74.1%

                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                          2. Add Preprocessing
                        3. Recombined 3 regimes into one program.
                        4. Final simplification80.0%

                          \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
                        5. Add Preprocessing

                        Alternative 10: 83.6% accurate, 0.9× speedup?

                        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(\lambda_1 - \lambda_2\right)\\ t_1 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t_1 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot t_0\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot t_0, t_1\right)\right)\\ \end{array} \end{array} \]
                        (FPCore (R lambda1 lambda2 phi1 phi2)
                         :precision binary64
                         (let* ((t_0 (cos (- lambda1 lambda2))) (t_1 (* (sin phi1) (sin phi2))))
                           (if (<= phi2 -4.2e-16)
                             (* R (acos (+ t_1 (* (* (cos phi1) (cos phi2)) t_0))))
                             (if (<= phi2 6.6e-5)
                               (*
                                R
                                (acos
                                 (*
                                  (cos phi1)
                                  (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))
                               (* R (acos (fma (cos phi1) (* (cos phi2) t_0) t_1)))))))
                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                        	double t_0 = cos((lambda1 - lambda2));
                        	double t_1 = sin(phi1) * sin(phi2);
                        	double tmp;
                        	if (phi2 <= -4.2e-16) {
                        		tmp = R * acos((t_1 + ((cos(phi1) * cos(phi2)) * t_0)));
                        	} else if (phi2 <= 6.6e-5) {
                        		tmp = R * acos((cos(phi1) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))));
                        	} else {
                        		tmp = R * acos(fma(cos(phi1), (cos(phi2) * t_0), t_1));
                        	}
                        	return tmp;
                        }
                        
                        function code(R, lambda1, lambda2, phi1, phi2)
                        	t_0 = cos(Float64(lambda1 - lambda2))
                        	t_1 = Float64(sin(phi1) * sin(phi2))
                        	tmp = 0.0
                        	if (phi2 <= -4.2e-16)
                        		tmp = Float64(R * acos(Float64(t_1 + Float64(Float64(cos(phi1) * cos(phi2)) * t_0))));
                        	elseif (phi2 <= 6.6e-5)
                        		tmp = Float64(R * acos(Float64(cos(phi1) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))));
                        	else
                        		tmp = Float64(R * acos(fma(cos(phi1), Float64(cos(phi2) * t_0), t_1)));
                        	end
                        	return tmp
                        end
                        
                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -4.2e-16], N[(R * N[ArcCos[N[(t$95$1 + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * t$95$0), $MachinePrecision] + t$95$1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]
                        
                        \begin{array}{l}
                        
                        \\
                        \begin{array}{l}
                        t_0 := \cos \left(\lambda_1 - \lambda_2\right)\\
                        t_1 := \sin \phi_1 \cdot \sin \phi_2\\
                        \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(t_1 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot t_0\right)\\
                        
                        \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                        
                        \mathbf{else}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot t_0, t_1\right)\right)\\
                        
                        
                        \end{array}
                        \end{array}
                        
                        Derivation
                        1. Split input into 3 regimes
                        2. if phi2 < -4.2000000000000002e-16

                          1. Initial program 71.9%

                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                          2. Add Preprocessing

                          if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                          1. Initial program 69.8%

                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                          2. Step-by-step derivation
                            1. Simplified69.8%

                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                            2. Add Preprocessing
                            3. Taylor expanded in phi2 around 0 69.8%

                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                            4. Step-by-step derivation
                              1. cos-diff88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                              2. *-commutative88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1\right)\right) \]
                              3. *-commutative88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}\right)\right) \]
                            5. Applied egg-rr88.7%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                            6. Step-by-step derivation
                              1. *-commutative88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) \]
                              2. fma-udef88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                              3. *-commutative88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right) \]
                            7. Simplified88.7%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]

                            if 6.6000000000000005e-5 < phi2

                            1. Initial program 74.1%

                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                            2. Step-by-step derivation
                              1. +-commutative74.1%

                                \[\leadsto \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
                              2. associate-*l*74.1%

                                \[\leadsto \cos^{-1} \left(\color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} + \sin \phi_1 \cdot \sin \phi_2\right) \cdot R \]
                              3. fma-def74.2%

                                \[\leadsto \cos^{-1} \color{blue}{\left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \cdot R \]
                            3. Simplified74.2%

                              \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot R} \]
                            4. Add Preprocessing
                          3. Recombined 3 regimes into one program.
                          4. Final simplification80.0%

                            \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
                          5. Add Preprocessing

                          Alternative 11: 83.6% accurate, 0.9× speedup?

                          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\\ \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot t_0\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, t_0, \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \end{array} \]
                          (FPCore (R lambda1 lambda2 phi1 phi2)
                           :precision binary64
                           (let* ((t_0 (* (cos phi2) (cos (- lambda1 lambda2)))))
                             (if (<= phi2 -4.2e-16)
                               (* R (acos (fma (sin phi1) (sin phi2) (* (cos phi1) t_0))))
                               (if (<= phi2 6.6e-5)
                                 (*
                                  R
                                  (acos
                                   (*
                                    (cos phi1)
                                    (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))
                                 (* R (acos (fma (cos phi1) t_0 (* (sin phi1) (sin phi2)))))))))
                          double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                          	double t_0 = cos(phi2) * cos((lambda1 - lambda2));
                          	double tmp;
                          	if (phi2 <= -4.2e-16) {
                          		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * t_0)));
                          	} else if (phi2 <= 6.6e-5) {
                          		tmp = R * acos((cos(phi1) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))));
                          	} else {
                          		tmp = R * acos(fma(cos(phi1), t_0, (sin(phi1) * sin(phi2))));
                          	}
                          	return tmp;
                          }
                          
                          function code(R, lambda1, lambda2, phi1, phi2)
                          	t_0 = Float64(cos(phi2) * cos(Float64(lambda1 - lambda2)))
                          	tmp = 0.0
                          	if (phi2 <= -4.2e-16)
                          		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * t_0))));
                          	elseif (phi2 <= 6.6e-5)
                          		tmp = Float64(R * acos(Float64(cos(phi1) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))));
                          	else
                          		tmp = Float64(R * acos(fma(cos(phi1), t_0, Float64(sin(phi1) * sin(phi2)))));
                          	end
                          	return tmp
                          end
                          
                          code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -4.2e-16], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * t$95$0 + N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                          
                          \begin{array}{l}
                          
                          \\
                          \begin{array}{l}
                          t_0 := \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\\
                          \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\
                          \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot t_0\right)\right)\\
                          
                          \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                          \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, t_0, \sin \phi_1 \cdot \sin \phi_2\right)\right)\\
                          
                          
                          \end{array}
                          \end{array}
                          
                          Derivation
                          1. Split input into 3 regimes
                          2. if phi2 < -4.2000000000000002e-16

                            1. Initial program 71.9%

                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                            2. Simplified72.0%

                              \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                            3. Add Preprocessing

                            if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                            1. Initial program 69.8%

                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                            2. Step-by-step derivation
                              1. Simplified69.8%

                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                              2. Add Preprocessing
                              3. Taylor expanded in phi2 around 0 69.8%

                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                              4. Step-by-step derivation
                                1. cos-diff88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                2. *-commutative88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1\right)\right) \]
                                3. *-commutative88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}\right)\right) \]
                              5. Applied egg-rr88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                              6. Step-by-step derivation
                                1. *-commutative88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) \]
                                2. fma-udef88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                                3. *-commutative88.7%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right) \]
                              7. Simplified88.7%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]

                              if 6.6000000000000005e-5 < phi2

                              1. Initial program 74.1%

                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                              2. Step-by-step derivation
                                1. +-commutative74.1%

                                  \[\leadsto \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
                                2. associate-*l*74.1%

                                  \[\leadsto \cos^{-1} \left(\color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} + \sin \phi_1 \cdot \sin \phi_2\right) \cdot R \]
                                3. fma-def74.2%

                                  \[\leadsto \cos^{-1} \color{blue}{\left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \cdot R \]
                              3. Simplified74.2%

                                \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot R} \]
                              4. Add Preprocessing
                            3. Recombined 3 regimes into one program.
                            4. Final simplification80.0%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
                            5. Add Preprocessing

                            Alternative 12: 83.6% accurate, 0.9× speedup?

                            \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), t_0\right)\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), t_0\right)\right)\\ \end{array} \end{array} \]
                            (FPCore (R lambda1 lambda2 phi1 phi2)
                             :precision binary64
                             (let* ((t_0 (* (sin phi1) (sin phi2))))
                               (if (<= phi2 -4.2e-16)
                                 (*
                                  R
                                  (-
                                   (* PI 0.5)
                                   (asin (fma (cos phi1) (* (cos phi2) (cos (- lambda2 lambda1))) t_0))))
                                 (if (<= phi2 6.6e-5)
                                   (*
                                    R
                                    (acos
                                     (*
                                      (cos phi1)
                                      (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))
                                   (*
                                    R
                                    (acos
                                     (fma (cos phi1) (* (cos phi2) (cos (- lambda1 lambda2))) t_0)))))))
                            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                            	double t_0 = sin(phi1) * sin(phi2);
                            	double tmp;
                            	if (phi2 <= -4.2e-16) {
                            		tmp = R * ((((double) M_PI) * 0.5) - asin(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), t_0)));
                            	} else if (phi2 <= 6.6e-5) {
                            		tmp = R * acos((cos(phi1) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))));
                            	} else {
                            		tmp = R * acos(fma(cos(phi1), (cos(phi2) * cos((lambda1 - lambda2))), t_0));
                            	}
                            	return tmp;
                            }
                            
                            function code(R, lambda1, lambda2, phi1, phi2)
                            	t_0 = Float64(sin(phi1) * sin(phi2))
                            	tmp = 0.0
                            	if (phi2 <= -4.2e-16)
                            		tmp = Float64(R * Float64(Float64(pi * 0.5) - asin(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), t_0))));
                            	elseif (phi2 <= 6.6e-5)
                            		tmp = Float64(R * acos(Float64(cos(phi1) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))));
                            	else
                            		tmp = Float64(R * acos(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda1 - lambda2))), t_0)));
                            	end
                            	return tmp
                            end
                            
                            code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -4.2e-16], N[(R * N[(N[(Pi * 0.5), $MachinePrecision] - N[ArcSin[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                            
                            \begin{array}{l}
                            
                            \\
                            \begin{array}{l}
                            t_0 := \sin \phi_1 \cdot \sin \phi_2\\
                            \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\
                            \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), t_0\right)\right)\right)\\
                            
                            \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                            \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), t_0\right)\right)\\
                            
                            
                            \end{array}
                            \end{array}
                            
                            Derivation
                            1. Split input into 3 regimes
                            2. if phi2 < -4.2000000000000002e-16

                              1. Initial program 71.9%

                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                              2. Step-by-step derivation
                                1. Simplified71.9%

                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                2. Add Preprocessing
                                3. Step-by-step derivation
                                  1. cos-diff98.3%

                                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                                  2. *-commutative98.3%

                                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                                  3. *-commutative98.3%

                                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                                  4. cos-diff71.9%

                                    \[\leadsto R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right) \]
                                  5. fma-def71.9%

                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]
                                  6. +-commutative71.9%

                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} \]
                                  7. acos-asin72.1%

                                    \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]
                                  8. sub-neg72.1%

                                    \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)} \]
                                  9. div-inv72.1%

                                    \[\leadsto R \cdot \left(\color{blue}{\pi \cdot \frac{1}{2}} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                                  10. metadata-eval72.1%

                                    \[\leadsto R \cdot \left(\pi \cdot \color{blue}{0.5} + \left(-\sin^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
                                  11. +-commutative72.1%

                                    \[\leadsto R \cdot \left(\pi \cdot 0.5 + \left(-\sin^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}\right)\right) \]
                                4. Applied egg-rr72.1%

                                  \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 + \left(-\sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\right)} \]
                                5. Step-by-step derivation
                                  1. sub-neg72.1%

                                    \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]
                                6. Simplified72.1%

                                  \[\leadsto R \cdot \color{blue}{\left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)} \]

                                if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                                1. Initial program 69.8%

                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                2. Step-by-step derivation
                                  1. Simplified69.8%

                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                  2. Add Preprocessing
                                  3. Taylor expanded in phi2 around 0 69.8%

                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                  4. Step-by-step derivation
                                    1. cos-diff88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                    2. *-commutative88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1\right)\right) \]
                                    3. *-commutative88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}\right)\right) \]
                                  5. Applied egg-rr88.7%

                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                                  6. Step-by-step derivation
                                    1. *-commutative88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) \]
                                    2. fma-udef88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                                    3. *-commutative88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right) \]
                                  7. Simplified88.7%

                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]

                                  if 6.6000000000000005e-5 < phi2

                                  1. Initial program 74.1%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Step-by-step derivation
                                    1. +-commutative74.1%

                                      \[\leadsto \cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
                                    2. associate-*l*74.1%

                                      \[\leadsto \cos^{-1} \left(\color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} + \sin \phi_1 \cdot \sin \phi_2\right) \cdot R \]
                                    3. fma-def74.2%

                                      \[\leadsto \cos^{-1} \color{blue}{\left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \cdot R \]
                                  3. Simplified74.2%

                                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right) \cdot R} \]
                                  4. Add Preprocessing
                                3. Recombined 3 regimes into one program.
                                4. Final simplification80.0%

                                  \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16}:\\ \;\;\;\;R \cdot \left(\pi \cdot 0.5 - \sin^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
                                5. Add Preprocessing

                                Alternative 13: 83.6% accurate, 0.9× speedup?

                                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \end{array} \end{array} \]
                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                 :precision binary64
                                 (if (or (<= phi2 -4.2e-16) (not (<= phi2 6.6e-5)))
                                   (*
                                    R
                                    (acos
                                     (+
                                      (* (sin phi1) (sin phi2))
                                      (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))))
                                   (*
                                    R
                                    (acos
                                     (*
                                      (cos phi1)
                                      (fma (cos lambda2) (cos lambda1) (* (sin lambda1) (sin lambda2))))))))
                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                	double tmp;
                                	if ((phi2 <= -4.2e-16) || !(phi2 <= 6.6e-5)) {
                                		tmp = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))));
                                	} else {
                                		tmp = R * acos((cos(phi1) * fma(cos(lambda2), cos(lambda1), (sin(lambda1) * sin(lambda2)))));
                                	}
                                	return tmp;
                                }
                                
                                function code(R, lambda1, lambda2, phi1, phi2)
                                	tmp = 0.0
                                	if ((phi2 <= -4.2e-16) || !(phi2 <= 6.6e-5))
                                		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))));
                                	else
                                		tmp = Float64(R * acos(Float64(cos(phi1) * fma(cos(lambda2), cos(lambda1), Float64(sin(lambda1) * sin(lambda2))))));
                                	end
                                	return tmp
                                end
                                
                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi2, -4.2e-16], N[Not[LessEqual[phi2, 6.6e-5]], $MachinePrecision]], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                
                                \begin{array}{l}
                                
                                \\
                                \begin{array}{l}
                                \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\
                                \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 2 regimes
                                2. if phi2 < -4.2000000000000002e-16 or 6.6000000000000005e-5 < phi2

                                  1. Initial program 73.1%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Add Preprocessing

                                  if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                                  1. Initial program 69.8%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Step-by-step derivation
                                    1. Simplified69.8%

                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                    2. Add Preprocessing
                                    3. Taylor expanded in phi2 around 0 69.8%

                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                    4. Step-by-step derivation
                                      1. cos-diff88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                      2. *-commutative88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1\right)\right) \]
                                      3. *-commutative88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}\right)\right) \]
                                    5. Applied egg-rr88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                                    6. Step-by-step derivation
                                      1. *-commutative88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) \]
                                      2. fma-udef88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right) \]
                                      3. *-commutative88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right) \]
                                    7. Simplified88.7%

                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                  3. Recombined 2 regimes into one program.
                                  4. Final simplification80.0%

                                    \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \end{array} \]
                                  5. Add Preprocessing

                                  Alternative 14: 83.6% accurate, 1.0× speedup?

                                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \end{array} \]
                                  (FPCore (R lambda1 lambda2 phi1 phi2)
                                   :precision binary64
                                   (if (or (<= phi2 -4.2e-16) (not (<= phi2 6.6e-5)))
                                     (*
                                      R
                                      (acos
                                       (+
                                        (* (sin phi1) (sin phi2))
                                        (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))))
                                     (*
                                      R
                                      (acos
                                       (*
                                        (cos phi1)
                                        (+ (* (sin lambda1) (sin lambda2)) (* (cos lambda2) (cos lambda1))))))))
                                  double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                  	double tmp;
                                  	if ((phi2 <= -4.2e-16) || !(phi2 <= 6.6e-5)) {
                                  		tmp = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))));
                                  	} else {
                                  		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                  	}
                                  	return tmp;
                                  }
                                  
                                  real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                      real(8), intent (in) :: r
                                      real(8), intent (in) :: lambda1
                                      real(8), intent (in) :: lambda2
                                      real(8), intent (in) :: phi1
                                      real(8), intent (in) :: phi2
                                      real(8) :: tmp
                                      if ((phi2 <= (-4.2d-16)) .or. (.not. (phi2 <= 6.6d-5))) then
                                          tmp = r * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))))
                                      else
                                          tmp = r * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))))
                                      end if
                                      code = tmp
                                  end function
                                  
                                  public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                  	double tmp;
                                  	if ((phi2 <= -4.2e-16) || !(phi2 <= 6.6e-5)) {
                                  		tmp = R * Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos((lambda1 - lambda2)))));
                                  	} else {
                                  		tmp = R * Math.acos((Math.cos(phi1) * ((Math.sin(lambda1) * Math.sin(lambda2)) + (Math.cos(lambda2) * Math.cos(lambda1)))));
                                  	}
                                  	return tmp;
                                  }
                                  
                                  def code(R, lambda1, lambda2, phi1, phi2):
                                  	tmp = 0
                                  	if (phi2 <= -4.2e-16) or not (phi2 <= 6.6e-5):
                                  		tmp = R * math.acos(((math.sin(phi1) * math.sin(phi2)) + ((math.cos(phi1) * math.cos(phi2)) * math.cos((lambda1 - lambda2)))))
                                  	else:
                                  		tmp = R * math.acos((math.cos(phi1) * ((math.sin(lambda1) * math.sin(lambda2)) + (math.cos(lambda2) * math.cos(lambda1)))))
                                  	return tmp
                                  
                                  function code(R, lambda1, lambda2, phi1, phi2)
                                  	tmp = 0.0
                                  	if ((phi2 <= -4.2e-16) || !(phi2 <= 6.6e-5))
                                  		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))));
                                  	else
                                  		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1))))));
                                  	end
                                  	return tmp
                                  end
                                  
                                  function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                  	tmp = 0.0;
                                  	if ((phi2 <= -4.2e-16) || ~((phi2 <= 6.6e-5)))
                                  		tmp = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))));
                                  	else
                                  		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                  	end
                                  	tmp_2 = tmp;
                                  end
                                  
                                  code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi2, -4.2e-16], N[Not[LessEqual[phi2, 6.6e-5]], $MachinePrecision]], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                  
                                  \begin{array}{l}
                                  
                                  \\
                                  \begin{array}{l}
                                  \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\
                                  \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\
                                  
                                  \mathbf{else}:\\
                                  \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\
                                  
                                  
                                  \end{array}
                                  \end{array}
                                  
                                  Derivation
                                  1. Split input into 2 regimes
                                  2. if phi2 < -4.2000000000000002e-16 or 6.6000000000000005e-5 < phi2

                                    1. Initial program 73.1%

                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                    2. Add Preprocessing

                                    if -4.2000000000000002e-16 < phi2 < 6.6000000000000005e-5

                                    1. Initial program 69.8%

                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                    2. Step-by-step derivation
                                      1. Simplified69.8%

                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                      2. Add Preprocessing
                                      3. Taylor expanded in phi2 around 0 69.8%

                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                      4. Step-by-step derivation
                                        1. cos-diff88.7%

                                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                        2. +-commutative88.7%

                                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                                        3. *-commutative88.7%

                                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                                        4. *-commutative88.7%

                                          \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                                      5. Applied egg-rr88.7%

                                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_1 \cdot \cos \lambda_2\right)}\right) \]
                                    3. Recombined 2 regimes into one program.
                                    4. Final simplification79.9%

                                      \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -4.2 \cdot 10^{-16} \lor \neg \left(\phi_2 \leq 6.6 \cdot 10^{-5}\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \]
                                    5. Add Preprocessing

                                    Alternative 15: 74.0% accurate, 1.0× speedup?

                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.00135 \lor \neg \left(\phi_2 \leq 0.185\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \end{array} \]
                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                     :precision binary64
                                     (if (or (<= phi2 -0.00135) (not (<= phi2 0.185)))
                                       (*
                                        R
                                        (acos
                                         (+
                                          (* (sin phi1) (sin phi2))
                                          (* (* (cos phi1) (cos phi2)) (cos lambda2)))))
                                       (*
                                        R
                                        (acos
                                         (*
                                          (cos phi1)
                                          (+ (* (sin lambda1) (sin lambda2)) (* (cos lambda2) (cos lambda1))))))))
                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                    	double tmp;
                                    	if ((phi2 <= -0.00135) || !(phi2 <= 0.185)) {
                                    		tmp = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda2))));
                                    	} else {
                                    		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                        real(8), intent (in) :: r
                                        real(8), intent (in) :: lambda1
                                        real(8), intent (in) :: lambda2
                                        real(8), intent (in) :: phi1
                                        real(8), intent (in) :: phi2
                                        real(8) :: tmp
                                        if ((phi2 <= (-0.00135d0)) .or. (.not. (phi2 <= 0.185d0))) then
                                            tmp = r * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda2))))
                                        else
                                            tmp = r * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))))
                                        end if
                                        code = tmp
                                    end function
                                    
                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                    	double tmp;
                                    	if ((phi2 <= -0.00135) || !(phi2 <= 0.185)) {
                                    		tmp = R * Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos(lambda2))));
                                    	} else {
                                    		tmp = R * Math.acos((Math.cos(phi1) * ((Math.sin(lambda1) * Math.sin(lambda2)) + (Math.cos(lambda2) * Math.cos(lambda1)))));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    def code(R, lambda1, lambda2, phi1, phi2):
                                    	tmp = 0
                                    	if (phi2 <= -0.00135) or not (phi2 <= 0.185):
                                    		tmp = R * math.acos(((math.sin(phi1) * math.sin(phi2)) + ((math.cos(phi1) * math.cos(phi2)) * math.cos(lambda2))))
                                    	else:
                                    		tmp = R * math.acos((math.cos(phi1) * ((math.sin(lambda1) * math.sin(lambda2)) + (math.cos(lambda2) * math.cos(lambda1)))))
                                    	return tmp
                                    
                                    function code(R, lambda1, lambda2, phi1, phi2)
                                    	tmp = 0.0
                                    	if ((phi2 <= -0.00135) || !(phi2 <= 0.185))
                                    		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(lambda2)))));
                                    	else
                                    		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1))))));
                                    	end
                                    	return tmp
                                    end
                                    
                                    function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                    	tmp = 0.0;
                                    	if ((phi2 <= -0.00135) || ~((phi2 <= 0.185)))
                                    		tmp = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda2))));
                                    	else
                                    		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                    	end
                                    	tmp_2 = tmp;
                                    end
                                    
                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[Or[LessEqual[phi2, -0.00135], N[Not[LessEqual[phi2, 0.185]], $MachinePrecision]], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \begin{array}{l}
                                    \mathbf{if}\;\phi_2 \leq -0.00135 \lor \neg \left(\phi_2 \leq 0.185\right):\\
                                    \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\
                                    
                                    \mathbf{else}:\\
                                    \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\
                                    
                                    
                                    \end{array}
                                    \end{array}
                                    
                                    Derivation
                                    1. Split input into 2 regimes
                                    2. if phi2 < -0.0013500000000000001 or 0.185 < phi2

                                      1. Initial program 72.8%

                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                      2. Step-by-step derivation
                                        1. Simplified72.8%

                                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                        2. Add Preprocessing
                                        3. Taylor expanded in lambda1 around 0 55.7%

                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \left(\cos \phi_1 \cdot \cos \phi_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]

                                        if -0.0013500000000000001 < phi2 < 0.185

                                        1. Initial program 70.2%

                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                        2. Step-by-step derivation
                                          1. Simplified70.2%

                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                          2. Add Preprocessing
                                          3. Taylor expanded in phi2 around 0 69.2%

                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                          4. Step-by-step derivation
                                            1. cos-diff87.6%

                                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                            2. +-commutative87.6%

                                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                                            3. *-commutative87.6%

                                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                                            4. *-commutative87.6%

                                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                                          5. Applied egg-rr87.6%

                                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_1 \cdot \cos \lambda_2\right)}\right) \]
                                        3. Recombined 2 regimes into one program.
                                        4. Final simplification70.2%

                                          \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.00135 \lor \neg \left(\phi_2 \leq 0.185\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \]
                                        5. Add Preprocessing

                                        Alternative 16: 73.2% accurate, 1.0× speedup?

                                        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\lambda_1 \leq -3 \cdot 10^{-6}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_1\right)\right)\right)\\ \mathbf{elif}\;\lambda_1 \leq 0.25:\\ \;\;\;\;R \cdot \cos^{-1} \left(t_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \end{array} \]
                                        (FPCore (R lambda1 lambda2 phi1 phi2)
                                         :precision binary64
                                         (let* ((t_0 (* (sin phi1) (sin phi2))))
                                           (if (<= lambda1 -3e-6)
                                             (* R (acos (+ t_0 (* (cos phi1) (* (cos phi2) (cos (- lambda1)))))))
                                             (if (<= lambda1 0.25)
                                               (* R (acos (+ t_0 (* (* (cos phi1) (cos phi2)) (cos lambda2)))))
                                               (*
                                                R
                                                (acos
                                                 (*
                                                  (cos phi1)
                                                  (+
                                                   (* (sin lambda1) (sin lambda2))
                                                   (* (cos lambda2) (cos lambda1))))))))))
                                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                        	double t_0 = sin(phi1) * sin(phi2);
                                        	double tmp;
                                        	if (lambda1 <= -3e-6) {
                                        		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(-lambda1)))));
                                        	} else if (lambda1 <= 0.25) {
                                        		tmp = R * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda2))));
                                        	} else {
                                        		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                        	}
                                        	return tmp;
                                        }
                                        
                                        real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                            real(8), intent (in) :: r
                                            real(8), intent (in) :: lambda1
                                            real(8), intent (in) :: lambda2
                                            real(8), intent (in) :: phi1
                                            real(8), intent (in) :: phi2
                                            real(8) :: t_0
                                            real(8) :: tmp
                                            t_0 = sin(phi1) * sin(phi2)
                                            if (lambda1 <= (-3d-6)) then
                                                tmp = r * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(-lambda1)))))
                                            else if (lambda1 <= 0.25d0) then
                                                tmp = r * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda2))))
                                            else
                                                tmp = r * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))))
                                            end if
                                            code = tmp
                                        end function
                                        
                                        public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                        	double t_0 = Math.sin(phi1) * Math.sin(phi2);
                                        	double tmp;
                                        	if (lambda1 <= -3e-6) {
                                        		tmp = R * Math.acos((t_0 + (Math.cos(phi1) * (Math.cos(phi2) * Math.cos(-lambda1)))));
                                        	} else if (lambda1 <= 0.25) {
                                        		tmp = R * Math.acos((t_0 + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos(lambda2))));
                                        	} else {
                                        		tmp = R * Math.acos((Math.cos(phi1) * ((Math.sin(lambda1) * Math.sin(lambda2)) + (Math.cos(lambda2) * Math.cos(lambda1)))));
                                        	}
                                        	return tmp;
                                        }
                                        
                                        def code(R, lambda1, lambda2, phi1, phi2):
                                        	t_0 = math.sin(phi1) * math.sin(phi2)
                                        	tmp = 0
                                        	if lambda1 <= -3e-6:
                                        		tmp = R * math.acos((t_0 + (math.cos(phi1) * (math.cos(phi2) * math.cos(-lambda1)))))
                                        	elif lambda1 <= 0.25:
                                        		tmp = R * math.acos((t_0 + ((math.cos(phi1) * math.cos(phi2)) * math.cos(lambda2))))
                                        	else:
                                        		tmp = R * math.acos((math.cos(phi1) * ((math.sin(lambda1) * math.sin(lambda2)) + (math.cos(lambda2) * math.cos(lambda1)))))
                                        	return tmp
                                        
                                        function code(R, lambda1, lambda2, phi1, phi2)
                                        	t_0 = Float64(sin(phi1) * sin(phi2))
                                        	tmp = 0.0
                                        	if (lambda1 <= -3e-6)
                                        		tmp = Float64(R * acos(Float64(t_0 + Float64(cos(phi1) * Float64(cos(phi2) * cos(Float64(-lambda1)))))));
                                        	elseif (lambda1 <= 0.25)
                                        		tmp = Float64(R * acos(Float64(t_0 + Float64(Float64(cos(phi1) * cos(phi2)) * cos(lambda2)))));
                                        	else
                                        		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1))))));
                                        	end
                                        	return tmp
                                        end
                                        
                                        function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                        	t_0 = sin(phi1) * sin(phi2);
                                        	tmp = 0.0;
                                        	if (lambda1 <= -3e-6)
                                        		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(-lambda1)))));
                                        	elseif (lambda1 <= 0.25)
                                        		tmp = R * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda2))));
                                        	else
                                        		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                        	end
                                        	tmp_2 = tmp;
                                        end
                                        
                                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[lambda1, -3e-6], N[(R * N[ArcCos[N[(t$95$0 + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[(-lambda1)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[lambda1, 0.25], N[(R * N[ArcCos[N[(t$95$0 + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                                        
                                        \begin{array}{l}
                                        
                                        \\
                                        \begin{array}{l}
                                        t_0 := \sin \phi_1 \cdot \sin \phi_2\\
                                        \mathbf{if}\;\lambda_1 \leq -3 \cdot 10^{-6}:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(t_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_1\right)\right)\right)\\
                                        
                                        \mathbf{elif}\;\lambda_1 \leq 0.25:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(t_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\
                                        
                                        \mathbf{else}:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\
                                        
                                        
                                        \end{array}
                                        \end{array}
                                        
                                        Derivation
                                        1. Split input into 3 regimes
                                        2. if lambda1 < -3.0000000000000001e-6

                                          1. Initial program 49.5%

                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                          2. Step-by-step derivation
                                            1. Simplified49.5%

                                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                            2. Add Preprocessing
                                            3. Taylor expanded in lambda2 around 0 49.8%

                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_1\right)\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]

                                            if -3.0000000000000001e-6 < lambda1 < 0.25

                                            1. Initial program 88.3%

                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                            2. Step-by-step derivation
                                              1. Simplified88.3%

                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                              2. Add Preprocessing
                                              3. Taylor expanded in lambda1 around 0 87.3%

                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \left(\cos \phi_1 \cdot \cos \phi_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \]

                                              if 0.25 < lambda1

                                              1. Initial program 62.6%

                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                              2. Step-by-step derivation
                                                1. Simplified62.6%

                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                2. Add Preprocessing
                                                3. Taylor expanded in phi2 around 0 47.0%

                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                4. Step-by-step derivation
                                                  1. cos-diff62.0%

                                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                                  2. +-commutative62.0%

                                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                                                  3. *-commutative62.0%

                                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                                                  4. *-commutative62.0%

                                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                                                5. Applied egg-rr62.0%

                                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_1 \cdot \cos \lambda_2\right)}\right) \]
                                              3. Recombined 3 regimes into one program.
                                              4. Final simplification71.1%

                                                \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -3 \cdot 10^{-6}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_1\right)\right)\right)\\ \mathbf{elif}\;\lambda_1 \leq 0.25:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \end{array} \]
                                              5. Add Preprocessing

                                              Alternative 17: 61.3% accurate, 1.0× speedup?

                                              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \end{array} \end{array} \]
                                              (FPCore (R lambda1 lambda2 phi1 phi2)
                                               :precision binary64
                                               (if (<= phi2 6.6e-5)
                                                 (*
                                                  R
                                                  (acos
                                                   (*
                                                    (cos phi1)
                                                    (+ (* (sin lambda1) (sin lambda2)) (* (cos lambda2) (cos lambda1))))))
                                                 (* R (acos (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))))
                                              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                              	double tmp;
                                              	if (phi2 <= 6.6e-5) {
                                              		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                              	} else {
                                              		tmp = R * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))));
                                              	}
                                              	return tmp;
                                              }
                                              
                                              real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                  real(8), intent (in) :: r
                                                  real(8), intent (in) :: lambda1
                                                  real(8), intent (in) :: lambda2
                                                  real(8), intent (in) :: phi1
                                                  real(8), intent (in) :: phi2
                                                  real(8) :: tmp
                                                  if (phi2 <= 6.6d-5) then
                                                      tmp = r * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))))
                                                  else
                                                      tmp = r * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))
                                                  end if
                                                  code = tmp
                                              end function
                                              
                                              public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                              	double tmp;
                                              	if (phi2 <= 6.6e-5) {
                                              		tmp = R * Math.acos((Math.cos(phi1) * ((Math.sin(lambda1) * Math.sin(lambda2)) + (Math.cos(lambda2) * Math.cos(lambda1)))));
                                              	} else {
                                              		tmp = R * Math.acos(((Math.cos(phi1) * Math.cos(phi2)) * Math.cos((lambda1 - lambda2))));
                                              	}
                                              	return tmp;
                                              }
                                              
                                              def code(R, lambda1, lambda2, phi1, phi2):
                                              	tmp = 0
                                              	if phi2 <= 6.6e-5:
                                              		tmp = R * math.acos((math.cos(phi1) * ((math.sin(lambda1) * math.sin(lambda2)) + (math.cos(lambda2) * math.cos(lambda1)))))
                                              	else:
                                              		tmp = R * math.acos(((math.cos(phi1) * math.cos(phi2)) * math.cos((lambda1 - lambda2))))
                                              	return tmp
                                              
                                              function code(R, lambda1, lambda2, phi1, phi2)
                                              	tmp = 0.0
                                              	if (phi2 <= 6.6e-5)
                                              		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(sin(lambda1) * sin(lambda2)) + Float64(cos(lambda2) * cos(lambda1))))));
                                              	else
                                              		tmp = Float64(R * acos(Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2)))));
                                              	end
                                              	return tmp
                                              end
                                              
                                              function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                              	tmp = 0.0;
                                              	if (phi2 <= 6.6e-5)
                                              		tmp = R * acos((cos(phi1) * ((sin(lambda1) * sin(lambda2)) + (cos(lambda2) * cos(lambda1)))));
                                              	else
                                              		tmp = R * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))));
                                              	end
                                              	tmp_2 = tmp;
                                              end
                                              
                                              code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi2, 6.6e-5], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[lambda2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                              
                                              \begin{array}{l}
                                              
                                              \\
                                              \begin{array}{l}
                                              \mathbf{if}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\
                                              \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\
                                              
                                              \mathbf{else}:\\
                                              \;\;\;\;R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\
                                              
                                              
                                              \end{array}
                                              \end{array}
                                              
                                              Derivation
                                              1. Split input into 2 regimes
                                              2. if phi2 < 6.6000000000000005e-5

                                                1. Initial program 70.6%

                                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                2. Step-by-step derivation
                                                  1. Simplified70.6%

                                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                  2. Add Preprocessing
                                                  3. Taylor expanded in phi2 around 0 50.7%

                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                  4. Step-by-step derivation
                                                    1. cos-diff62.5%

                                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                                    2. +-commutative62.5%

                                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                                                    3. *-commutative62.5%

                                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                                                    4. *-commutative62.5%

                                                      \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                                                  5. Applied egg-rr62.5%

                                                    \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_1 \cdot \cos \lambda_2\right)}\right) \]

                                                  if 6.6000000000000005e-5 < phi2

                                                  1. Initial program 74.1%

                                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  2. Add Preprocessing
                                                  3. Step-by-step derivation
                                                    1. *-commutative74.1%

                                                      \[\leadsto \cos^{-1} \left(\color{blue}{\sin \phi_2 \cdot \sin \phi_1} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                    2. sin-mult44.6%

                                                      \[\leadsto \cos^{-1} \left(\color{blue}{\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \left(\phi_2 + \phi_1\right)}{2}} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                    3. +-commutative44.6%

                                                      \[\leadsto \cos^{-1} \left(\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \color{blue}{\left(\phi_1 + \phi_2\right)}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  4. Applied egg-rr44.6%

                                                    \[\leadsto \cos^{-1} \left(\color{blue}{\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \left(\phi_1 + \phi_2\right)}{2}} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  5. Taylor expanded in phi2 around 0 44.6%

                                                    \[\leadsto \cos^{-1} \left(\frac{\color{blue}{\cos \left(-\phi_1\right) - \cos \phi_1}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  6. Step-by-step derivation
                                                    1. cos-neg44.6%

                                                      \[\leadsto \cos^{-1} \left(\frac{\color{blue}{\cos \phi_1} - \cos \phi_1}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                    2. +-inverses44.6%

                                                      \[\leadsto \cos^{-1} \left(\frac{\color{blue}{0}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  7. Simplified44.6%

                                                    \[\leadsto \cos^{-1} \left(\frac{\color{blue}{0}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                3. Recombined 2 regimes into one program.
                                                4. Final simplification57.2%

                                                  \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq 6.6 \cdot 10^{-5}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \cos \lambda_2 \cdot \cos \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \end{array} \]
                                                5. Add Preprocessing

                                                Alternative 18: 58.3% accurate, 1.5× speedup?

                                                \[\begin{array}{l} \\ R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \end{array} \]
                                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                                 :precision binary64
                                                 (* R (acos (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))))
                                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                	return R * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))));
                                                }
                                                
                                                real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                    real(8), intent (in) :: r
                                                    real(8), intent (in) :: lambda1
                                                    real(8), intent (in) :: lambda2
                                                    real(8), intent (in) :: phi1
                                                    real(8), intent (in) :: phi2
                                                    code = r * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))
                                                end function
                                                
                                                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                	return R * Math.acos(((Math.cos(phi1) * Math.cos(phi2)) * Math.cos((lambda1 - lambda2))));
                                                }
                                                
                                                def code(R, lambda1, lambda2, phi1, phi2):
                                                	return R * math.acos(((math.cos(phi1) * math.cos(phi2)) * math.cos((lambda1 - lambda2))))
                                                
                                                function code(R, lambda1, lambda2, phi1, phi2)
                                                	return Float64(R * acos(Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2)))))
                                                end
                                                
                                                function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                	tmp = R * acos(((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))));
                                                end
                                                
                                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[ArcCos[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                                                
                                                \begin{array}{l}
                                                
                                                \\
                                                R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)
                                                \end{array}
                                                
                                                Derivation
                                                1. Initial program 71.6%

                                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                2. Add Preprocessing
                                                3. Step-by-step derivation
                                                  1. *-commutative71.6%

                                                    \[\leadsto \cos^{-1} \left(\color{blue}{\sin \phi_2 \cdot \sin \phi_1} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  2. sin-mult55.5%

                                                    \[\leadsto \cos^{-1} \left(\color{blue}{\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \left(\phi_2 + \phi_1\right)}{2}} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  3. +-commutative55.5%

                                                    \[\leadsto \cos^{-1} \left(\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \color{blue}{\left(\phi_1 + \phi_2\right)}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                4. Applied egg-rr55.5%

                                                  \[\leadsto \cos^{-1} \left(\color{blue}{\frac{\cos \left(\phi_2 - \phi_1\right) - \cos \left(\phi_1 + \phi_2\right)}{2}} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                5. Taylor expanded in phi2 around 0 55.4%

                                                  \[\leadsto \cos^{-1} \left(\frac{\color{blue}{\cos \left(-\phi_1\right) - \cos \phi_1}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                6. Step-by-step derivation
                                                  1. cos-neg55.4%

                                                    \[\leadsto \cos^{-1} \left(\frac{\color{blue}{\cos \phi_1} - \cos \phi_1}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  2. +-inverses55.4%

                                                    \[\leadsto \cos^{-1} \left(\frac{\color{blue}{0}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                7. Simplified55.4%

                                                  \[\leadsto \cos^{-1} \left(\frac{\color{blue}{0}}{2} + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                8. Final simplification55.4%

                                                  \[\leadsto R \cdot \cos^{-1} \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \]
                                                9. Add Preprocessing

                                                Alternative 19: 50.4% accurate, 2.0× speedup?

                                                \[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(\lambda_2 - \lambda_1\right)\\ \mathbf{if}\;\phi_2 \leq 3.4 \cdot 10^{-9}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot t_0\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot t_0\right)\\ \end{array} \end{array} \]
                                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                                 :precision binary64
                                                 (let* ((t_0 (cos (- lambda2 lambda1))))
                                                   (if (<= phi2 3.4e-9)
                                                     (* R (acos (* (cos phi1) t_0)))
                                                     (* R (acos (* (cos phi2) t_0))))))
                                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                	double t_0 = cos((lambda2 - lambda1));
                                                	double tmp;
                                                	if (phi2 <= 3.4e-9) {
                                                		tmp = R * acos((cos(phi1) * t_0));
                                                	} else {
                                                		tmp = R * acos((cos(phi2) * t_0));
                                                	}
                                                	return tmp;
                                                }
                                                
                                                real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                    real(8), intent (in) :: r
                                                    real(8), intent (in) :: lambda1
                                                    real(8), intent (in) :: lambda2
                                                    real(8), intent (in) :: phi1
                                                    real(8), intent (in) :: phi2
                                                    real(8) :: t_0
                                                    real(8) :: tmp
                                                    t_0 = cos((lambda2 - lambda1))
                                                    if (phi2 <= 3.4d-9) then
                                                        tmp = r * acos((cos(phi1) * t_0))
                                                    else
                                                        tmp = r * acos((cos(phi2) * t_0))
                                                    end if
                                                    code = tmp
                                                end function
                                                
                                                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                	double t_0 = Math.cos((lambda2 - lambda1));
                                                	double tmp;
                                                	if (phi2 <= 3.4e-9) {
                                                		tmp = R * Math.acos((Math.cos(phi1) * t_0));
                                                	} else {
                                                		tmp = R * Math.acos((Math.cos(phi2) * t_0));
                                                	}
                                                	return tmp;
                                                }
                                                
                                                def code(R, lambda1, lambda2, phi1, phi2):
                                                	t_0 = math.cos((lambda2 - lambda1))
                                                	tmp = 0
                                                	if phi2 <= 3.4e-9:
                                                		tmp = R * math.acos((math.cos(phi1) * t_0))
                                                	else:
                                                		tmp = R * math.acos((math.cos(phi2) * t_0))
                                                	return tmp
                                                
                                                function code(R, lambda1, lambda2, phi1, phi2)
                                                	t_0 = cos(Float64(lambda2 - lambda1))
                                                	tmp = 0.0
                                                	if (phi2 <= 3.4e-9)
                                                		tmp = Float64(R * acos(Float64(cos(phi1) * t_0)));
                                                	else
                                                		tmp = Float64(R * acos(Float64(cos(phi2) * t_0)));
                                                	end
                                                	return tmp
                                                end
                                                
                                                function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                	t_0 = cos((lambda2 - lambda1));
                                                	tmp = 0.0;
                                                	if (phi2 <= 3.4e-9)
                                                		tmp = R * acos((cos(phi1) * t_0));
                                                	else
                                                		tmp = R * acos((cos(phi2) * t_0));
                                                	end
                                                	tmp_2 = tmp;
                                                end
                                                
                                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[phi2, 3.4e-9], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
                                                
                                                \begin{array}{l}
                                                
                                                \\
                                                \begin{array}{l}
                                                t_0 := \cos \left(\lambda_2 - \lambda_1\right)\\
                                                \mathbf{if}\;\phi_2 \leq 3.4 \cdot 10^{-9}:\\
                                                \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot t_0\right)\\
                                                
                                                \mathbf{else}:\\
                                                \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot t_0\right)\\
                                                
                                                
                                                \end{array}
                                                \end{array}
                                                
                                                Derivation
                                                1. Split input into 2 regimes
                                                2. if phi2 < 3.3999999999999998e-9

                                                  1. Initial program 70.9%

                                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  2. Step-by-step derivation
                                                    1. Simplified70.9%

                                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                    2. Add Preprocessing
                                                    3. Taylor expanded in phi2 around 0 50.9%

                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]

                                                    if 3.3999999999999998e-9 < phi2

                                                    1. Initial program 73.4%

                                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                    2. Step-by-step derivation
                                                      1. Simplified73.4%

                                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                      2. Add Preprocessing
                                                      3. Taylor expanded in phi1 around 0 43.9%

                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                    3. Recombined 2 regimes into one program.
                                                    4. Final simplification48.8%

                                                      \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq 3.4 \cdot 10^{-9}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \]
                                                    5. Add Preprocessing

                                                    Alternative 20: 34.6% accurate, 2.0× speedup?

                                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 0.32:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\ \end{array} \end{array} \]
                                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                                     :precision binary64
                                                     (if (<= lambda2 0.32)
                                                       (* R (acos (* (cos phi1) (cos lambda1))))
                                                       (* R (acos (cos lambda2)))))
                                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                    	double tmp;
                                                    	if (lambda2 <= 0.32) {
                                                    		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                                    	} else {
                                                    		tmp = R * acos(cos(lambda2));
                                                    	}
                                                    	return tmp;
                                                    }
                                                    
                                                    real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                        real(8), intent (in) :: r
                                                        real(8), intent (in) :: lambda1
                                                        real(8), intent (in) :: lambda2
                                                        real(8), intent (in) :: phi1
                                                        real(8), intent (in) :: phi2
                                                        real(8) :: tmp
                                                        if (lambda2 <= 0.32d0) then
                                                            tmp = r * acos((cos(phi1) * cos(lambda1)))
                                                        else
                                                            tmp = r * acos(cos(lambda2))
                                                        end if
                                                        code = tmp
                                                    end function
                                                    
                                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                    	double tmp;
                                                    	if (lambda2 <= 0.32) {
                                                    		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda1)));
                                                    	} else {
                                                    		tmp = R * Math.acos(Math.cos(lambda2));
                                                    	}
                                                    	return tmp;
                                                    }
                                                    
                                                    def code(R, lambda1, lambda2, phi1, phi2):
                                                    	tmp = 0
                                                    	if lambda2 <= 0.32:
                                                    		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda1)))
                                                    	else:
                                                    		tmp = R * math.acos(math.cos(lambda2))
                                                    	return tmp
                                                    
                                                    function code(R, lambda1, lambda2, phi1, phi2)
                                                    	tmp = 0.0
                                                    	if (lambda2 <= 0.32)
                                                    		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda1))));
                                                    	else
                                                    		tmp = Float64(R * acos(cos(lambda2)));
                                                    	end
                                                    	return tmp
                                                    end
                                                    
                                                    function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                    	tmp = 0.0;
                                                    	if (lambda2 <= 0.32)
                                                    		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                                    	else
                                                    		tmp = R * acos(cos(lambda2));
                                                    	end
                                                    	tmp_2 = tmp;
                                                    end
                                                    
                                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda2, 0.32], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[Cos[lambda2], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                    
                                                    \begin{array}{l}
                                                    
                                                    \\
                                                    \begin{array}{l}
                                                    \mathbf{if}\;\lambda_2 \leq 0.32:\\
                                                    \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\
                                                    
                                                    \mathbf{else}:\\
                                                    \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\
                                                    
                                                    
                                                    \end{array}
                                                    \end{array}
                                                    
                                                    Derivation
                                                    1. Split input into 2 regimes
                                                    2. if lambda2 < 0.320000000000000007

                                                      1. Initial program 77.8%

                                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                      2. Step-by-step derivation
                                                        1. Simplified77.8%

                                                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                        2. Add Preprocessing
                                                        3. Taylor expanded in phi2 around 0 44.2%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                        4. Taylor expanded in lambda2 around 0 35.2%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(-\lambda_1\right)\right)} \]
                                                        5. Step-by-step derivation
                                                          1. cos-neg35.2%

                                                            \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\cos \lambda_1}\right) \]
                                                        6. Simplified35.2%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_1\right)} \]

                                                        if 0.320000000000000007 < lambda2

                                                        1. Initial program 52.2%

                                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                        2. Step-by-step derivation
                                                          1. Simplified52.2%

                                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                          2. Add Preprocessing
                                                          3. Taylor expanded in phi2 around 0 34.3%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                          4. Taylor expanded in phi1 around 0 25.3%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                          5. Taylor expanded in lambda1 around 0 25.2%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_2} \]
                                                        3. Recombined 2 regimes into one program.
                                                        4. Final simplification32.8%

                                                          \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 0.32:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\ \end{array} \]
                                                        5. Add Preprocessing

                                                        Alternative 21: 37.0% accurate, 2.0× speedup?

                                                        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \end{array} \end{array} \]
                                                        (FPCore (R lambda1 lambda2 phi1 phi2)
                                                         :precision binary64
                                                         (if (<= lambda2 1.08e-13)
                                                           (* R (acos (* (cos phi1) (cos lambda1))))
                                                           (* R (acos (* (cos phi1) (cos lambda2))))))
                                                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                        	double tmp;
                                                        	if (lambda2 <= 1.08e-13) {
                                                        		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                                        	} else {
                                                        		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                                        	}
                                                        	return tmp;
                                                        }
                                                        
                                                        real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                            real(8), intent (in) :: r
                                                            real(8), intent (in) :: lambda1
                                                            real(8), intent (in) :: lambda2
                                                            real(8), intent (in) :: phi1
                                                            real(8), intent (in) :: phi2
                                                            real(8) :: tmp
                                                            if (lambda2 <= 1.08d-13) then
                                                                tmp = r * acos((cos(phi1) * cos(lambda1)))
                                                            else
                                                                tmp = r * acos((cos(phi1) * cos(lambda2)))
                                                            end if
                                                            code = tmp
                                                        end function
                                                        
                                                        public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                        	double tmp;
                                                        	if (lambda2 <= 1.08e-13) {
                                                        		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda1)));
                                                        	} else {
                                                        		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda2)));
                                                        	}
                                                        	return tmp;
                                                        }
                                                        
                                                        def code(R, lambda1, lambda2, phi1, phi2):
                                                        	tmp = 0
                                                        	if lambda2 <= 1.08e-13:
                                                        		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda1)))
                                                        	else:
                                                        		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda2)))
                                                        	return tmp
                                                        
                                                        function code(R, lambda1, lambda2, phi1, phi2)
                                                        	tmp = 0.0
                                                        	if (lambda2 <= 1.08e-13)
                                                        		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda1))));
                                                        	else
                                                        		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda2))));
                                                        	end
                                                        	return tmp
                                                        end
                                                        
                                                        function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                        	tmp = 0.0;
                                                        	if (lambda2 <= 1.08e-13)
                                                        		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                                        	else
                                                        		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                                        	end
                                                        	tmp_2 = tmp;
                                                        end
                                                        
                                                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda2, 1.08e-13], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                        
                                                        \begin{array}{l}
                                                        
                                                        \\
                                                        \begin{array}{l}
                                                        \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\
                                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\
                                                        
                                                        \mathbf{else}:\\
                                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\
                                                        
                                                        
                                                        \end{array}
                                                        \end{array}
                                                        
                                                        Derivation
                                                        1. Split input into 2 regimes
                                                        2. if lambda2 < 1.0799999999999999e-13

                                                          1. Initial program 77.8%

                                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                          2. Step-by-step derivation
                                                            1. Simplified77.8%

                                                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                            2. Add Preprocessing
                                                            3. Taylor expanded in phi2 around 0 44.5%

                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                            4. Taylor expanded in lambda2 around 0 35.4%

                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(-\lambda_1\right)\right)} \]
                                                            5. Step-by-step derivation
                                                              1. cos-neg35.4%

                                                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\cos \lambda_1}\right) \]
                                                            6. Simplified35.4%

                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_1\right)} \]

                                                            if 1.0799999999999999e-13 < lambda2

                                                            1. Initial program 53.9%

                                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                            2. Step-by-step derivation
                                                              1. Simplified53.9%

                                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                              2. Add Preprocessing
                                                              3. Taylor expanded in phi2 around 0 34.1%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                              4. Taylor expanded in lambda1 around 0 34.3%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_1\right)} \]
                                                              5. Step-by-step derivation
                                                                1. *-commutative34.3%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_2\right)} \]
                                                              6. Simplified34.3%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_2\right)} \]
                                                            3. Recombined 2 regimes into one program.
                                                            4. Final simplification35.1%

                                                              \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \end{array} \]
                                                            5. Add Preprocessing

                                                            Alternative 22: 43.2% accurate, 2.0× speedup?

                                                            \[\begin{array}{l} \\ R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \end{array} \]
                                                            (FPCore (R lambda1 lambda2 phi1 phi2)
                                                             :precision binary64
                                                             (* R (acos (* (cos phi1) (cos (- lambda2 lambda1))))))
                                                            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                            	return R * acos((cos(phi1) * cos((lambda2 - lambda1))));
                                                            }
                                                            
                                                            real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                real(8), intent (in) :: r
                                                                real(8), intent (in) :: lambda1
                                                                real(8), intent (in) :: lambda2
                                                                real(8), intent (in) :: phi1
                                                                real(8), intent (in) :: phi2
                                                                code = r * acos((cos(phi1) * cos((lambda2 - lambda1))))
                                                            end function
                                                            
                                                            public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                            	return R * Math.acos((Math.cos(phi1) * Math.cos((lambda2 - lambda1))));
                                                            }
                                                            
                                                            def code(R, lambda1, lambda2, phi1, phi2):
                                                            	return R * math.acos((math.cos(phi1) * math.cos((lambda2 - lambda1))))
                                                            
                                                            function code(R, lambda1, lambda2, phi1, phi2)
                                                            	return Float64(R * acos(Float64(cos(phi1) * cos(Float64(lambda2 - lambda1)))))
                                                            end
                                                            
                                                            function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                            	tmp = R * acos((cos(phi1) * cos((lambda2 - lambda1))));
                                                            end
                                                            
                                                            code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                                                            
                                                            \begin{array}{l}
                                                            
                                                            \\
                                                            R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)
                                                            \end{array}
                                                            
                                                            Derivation
                                                            1. Initial program 71.6%

                                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                            2. Step-by-step derivation
                                                              1. Simplified71.6%

                                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                              2. Add Preprocessing
                                                              3. Taylor expanded in phi2 around 0 41.8%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                              4. Final simplification41.8%

                                                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                                              5. Add Preprocessing

                                                              Alternative 23: 26.4% accurate, 2.9× speedup?

                                                              \[\begin{array}{l} \\ R \cdot \left(\frac{\pi}{2} - \sin^{-1} \cos \left(\lambda_2 - \lambda_1\right)\right) \end{array} \]
                                                              (FPCore (R lambda1 lambda2 phi1 phi2)
                                                               :precision binary64
                                                               (* R (- (/ PI 2.0) (asin (cos (- lambda2 lambda1))))))
                                                              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                              	return R * ((((double) M_PI) / 2.0) - asin(cos((lambda2 - lambda1))));
                                                              }
                                                              
                                                              public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                              	return R * ((Math.PI / 2.0) - Math.asin(Math.cos((lambda2 - lambda1))));
                                                              }
                                                              
                                                              def code(R, lambda1, lambda2, phi1, phi2):
                                                              	return R * ((math.pi / 2.0) - math.asin(math.cos((lambda2 - lambda1))))
                                                              
                                                              function code(R, lambda1, lambda2, phi1, phi2)
                                                              	return Float64(R * Float64(Float64(pi / 2.0) - asin(cos(Float64(lambda2 - lambda1)))))
                                                              end
                                                              
                                                              function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                              	tmp = R * ((pi / 2.0) - asin(cos((lambda2 - lambda1))));
                                                              end
                                                              
                                                              code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[(N[(Pi / 2.0), $MachinePrecision] - N[ArcSin[N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                                                              
                                                              \begin{array}{l}
                                                              
                                                              \\
                                                              R \cdot \left(\frac{\pi}{2} - \sin^{-1} \cos \left(\lambda_2 - \lambda_1\right)\right)
                                                              \end{array}
                                                              
                                                              Derivation
                                                              1. Initial program 71.6%

                                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                              2. Step-by-step derivation
                                                                1. Simplified71.6%

                                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                2. Add Preprocessing
                                                                3. Taylor expanded in phi2 around 0 41.8%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                4. Taylor expanded in phi1 around 0 24.2%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                5. Step-by-step derivation
                                                                  1. acos-asin24.2%

                                                                    \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                6. Applied egg-rr24.2%

                                                                  \[\leadsto R \cdot \color{blue}{\left(\frac{\pi}{2} - \sin^{-1} \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                7. Final simplification24.2%

                                                                  \[\leadsto R \cdot \left(\frac{\pi}{2} - \sin^{-1} \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                                                8. Add Preprocessing

                                                                Alternative 24: 11.9% accurate, 2.9× speedup?

                                                                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -5.3 \cdot 10^{-8}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
                                                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                 :precision binary64
                                                                 (if (<= lambda1 -5.3e-8)
                                                                   (* R (acos (cos lambda1)))
                                                                   (* R (- lambda2 lambda1))))
                                                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                	double tmp;
                                                                	if (lambda1 <= -5.3e-8) {
                                                                		tmp = R * acos(cos(lambda1));
                                                                	} else {
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	}
                                                                	return tmp;
                                                                }
                                                                
                                                                real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                    real(8), intent (in) :: r
                                                                    real(8), intent (in) :: lambda1
                                                                    real(8), intent (in) :: lambda2
                                                                    real(8), intent (in) :: phi1
                                                                    real(8), intent (in) :: phi2
                                                                    real(8) :: tmp
                                                                    if (lambda1 <= (-5.3d-8)) then
                                                                        tmp = r * acos(cos(lambda1))
                                                                    else
                                                                        tmp = r * (lambda2 - lambda1)
                                                                    end if
                                                                    code = tmp
                                                                end function
                                                                
                                                                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                	double tmp;
                                                                	if (lambda1 <= -5.3e-8) {
                                                                		tmp = R * Math.acos(Math.cos(lambda1));
                                                                	} else {
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	}
                                                                	return tmp;
                                                                }
                                                                
                                                                def code(R, lambda1, lambda2, phi1, phi2):
                                                                	tmp = 0
                                                                	if lambda1 <= -5.3e-8:
                                                                		tmp = R * math.acos(math.cos(lambda1))
                                                                	else:
                                                                		tmp = R * (lambda2 - lambda1)
                                                                	return tmp
                                                                
                                                                function code(R, lambda1, lambda2, phi1, phi2)
                                                                	tmp = 0.0
                                                                	if (lambda1 <= -5.3e-8)
                                                                		tmp = Float64(R * acos(cos(lambda1)));
                                                                	else
                                                                		tmp = Float64(R * Float64(lambda2 - lambda1));
                                                                	end
                                                                	return tmp
                                                                end
                                                                
                                                                function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                                	tmp = 0.0;
                                                                	if (lambda1 <= -5.3e-8)
                                                                		tmp = R * acos(cos(lambda1));
                                                                	else
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	end
                                                                	tmp_2 = tmp;
                                                                end
                                                                
                                                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -5.3e-8], N[(R * N[ArcCos[N[Cos[lambda1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]
                                                                
                                                                \begin{array}{l}
                                                                
                                                                \\
                                                                \begin{array}{l}
                                                                \mathbf{if}\;\lambda_1 \leq -5.3 \cdot 10^{-8}:\\
                                                                \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\
                                                                
                                                                \mathbf{else}:\\
                                                                \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\
                                                                
                                                                
                                                                \end{array}
                                                                \end{array}
                                                                
                                                                Derivation
                                                                1. Split input into 2 regimes
                                                                2. if lambda1 < -5.2999999999999998e-8

                                                                  1. Initial program 49.5%

                                                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                  2. Step-by-step derivation
                                                                    1. Simplified49.5%

                                                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                    2. Add Preprocessing
                                                                    3. Taylor expanded in phi2 around 0 28.8%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                    4. Taylor expanded in phi1 around 0 23.7%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                    5. Taylor expanded in lambda2 around 0 23.4%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(-\lambda_1\right)} \]
                                                                    6. Step-by-step derivation
                                                                      1. cos-neg23.4%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]
                                                                    7. Simplified23.4%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]

                                                                    if -5.2999999999999998e-8 < lambda1

                                                                    1. Initial program 78.5%

                                                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                    2. Step-by-step derivation
                                                                      1. Simplified78.6%

                                                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                      2. Add Preprocessing
                                                                      3. Taylor expanded in phi2 around 0 45.9%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                      4. Taylor expanded in phi1 around 0 24.4%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                      5. Taylor expanded in lambda2 around 0 4.1%

                                                                        \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
                                                                      6. Step-by-step derivation
                                                                        1. neg-mul-14.1%

                                                                          \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
                                                                        2. sub-neg4.1%

                                                                          \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
                                                                      7. Simplified4.1%

                                                                        \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
                                                                    3. Recombined 2 regimes into one program.
                                                                    4. Final simplification8.7%

                                                                      \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -5.3 \cdot 10^{-8}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \]
                                                                    5. Add Preprocessing

                                                                    Alternative 25: 21.8% accurate, 2.9× speedup?

                                                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\ \end{array} \end{array} \]
                                                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                     :precision binary64
                                                                     (if (<= lambda2 1.08e-13)
                                                                       (* R (acos (cos lambda1)))
                                                                       (* R (acos (cos lambda2)))))
                                                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                    	double tmp;
                                                                    	if (lambda2 <= 1.08e-13) {
                                                                    		tmp = R * acos(cos(lambda1));
                                                                    	} else {
                                                                    		tmp = R * acos(cos(lambda2));
                                                                    	}
                                                                    	return tmp;
                                                                    }
                                                                    
                                                                    real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                        real(8), intent (in) :: r
                                                                        real(8), intent (in) :: lambda1
                                                                        real(8), intent (in) :: lambda2
                                                                        real(8), intent (in) :: phi1
                                                                        real(8), intent (in) :: phi2
                                                                        real(8) :: tmp
                                                                        if (lambda2 <= 1.08d-13) then
                                                                            tmp = r * acos(cos(lambda1))
                                                                        else
                                                                            tmp = r * acos(cos(lambda2))
                                                                        end if
                                                                        code = tmp
                                                                    end function
                                                                    
                                                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                    	double tmp;
                                                                    	if (lambda2 <= 1.08e-13) {
                                                                    		tmp = R * Math.acos(Math.cos(lambda1));
                                                                    	} else {
                                                                    		tmp = R * Math.acos(Math.cos(lambda2));
                                                                    	}
                                                                    	return tmp;
                                                                    }
                                                                    
                                                                    def code(R, lambda1, lambda2, phi1, phi2):
                                                                    	tmp = 0
                                                                    	if lambda2 <= 1.08e-13:
                                                                    		tmp = R * math.acos(math.cos(lambda1))
                                                                    	else:
                                                                    		tmp = R * math.acos(math.cos(lambda2))
                                                                    	return tmp
                                                                    
                                                                    function code(R, lambda1, lambda2, phi1, phi2)
                                                                    	tmp = 0.0
                                                                    	if (lambda2 <= 1.08e-13)
                                                                    		tmp = Float64(R * acos(cos(lambda1)));
                                                                    	else
                                                                    		tmp = Float64(R * acos(cos(lambda2)));
                                                                    	end
                                                                    	return tmp
                                                                    end
                                                                    
                                                                    function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                                    	tmp = 0.0;
                                                                    	if (lambda2 <= 1.08e-13)
                                                                    		tmp = R * acos(cos(lambda1));
                                                                    	else
                                                                    		tmp = R * acos(cos(lambda2));
                                                                    	end
                                                                    	tmp_2 = tmp;
                                                                    end
                                                                    
                                                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda2, 1.08e-13], N[(R * N[ArcCos[N[Cos[lambda1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[Cos[lambda2], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                                    
                                                                    \begin{array}{l}
                                                                    
                                                                    \\
                                                                    \begin{array}{l}
                                                                    \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\
                                                                    \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\
                                                                    
                                                                    \mathbf{else}:\\
                                                                    \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\
                                                                    
                                                                    
                                                                    \end{array}
                                                                    \end{array}
                                                                    
                                                                    Derivation
                                                                    1. Split input into 2 regimes
                                                                    2. if lambda2 < 1.0799999999999999e-13

                                                                      1. Initial program 77.8%

                                                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                      2. Step-by-step derivation
                                                                        1. Simplified77.8%

                                                                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                        2. Add Preprocessing
                                                                        3. Taylor expanded in phi2 around 0 44.5%

                                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                        4. Taylor expanded in phi1 around 0 24.2%

                                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                        5. Taylor expanded in lambda2 around 0 18.7%

                                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(-\lambda_1\right)} \]
                                                                        6. Step-by-step derivation
                                                                          1. cos-neg18.7%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]
                                                                        7. Simplified18.7%

                                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]

                                                                        if 1.0799999999999999e-13 < lambda2

                                                                        1. Initial program 53.9%

                                                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                        2. Step-by-step derivation
                                                                          1. Simplified53.9%

                                                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                          2. Add Preprocessing
                                                                          3. Taylor expanded in phi2 around 0 34.1%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                          4. Taylor expanded in phi1 around 0 24.3%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                          5. Taylor expanded in lambda1 around 0 24.2%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_2} \]
                                                                        3. Recombined 2 regimes into one program.
                                                                        4. Final simplification20.1%

                                                                          \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 1.08 \cdot 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\ \end{array} \]
                                                                        5. Add Preprocessing

                                                                        Alternative 26: 26.4% accurate, 3.0× speedup?

                                                                        \[\begin{array}{l} \\ R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right) \end{array} \]
                                                                        (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                         :precision binary64
                                                                         (* R (acos (cos (- lambda2 lambda1)))))
                                                                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                        	return R * acos(cos((lambda2 - lambda1)));
                                                                        }
                                                                        
                                                                        real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                            real(8), intent (in) :: r
                                                                            real(8), intent (in) :: lambda1
                                                                            real(8), intent (in) :: lambda2
                                                                            real(8), intent (in) :: phi1
                                                                            real(8), intent (in) :: phi2
                                                                            code = r * acos(cos((lambda2 - lambda1)))
                                                                        end function
                                                                        
                                                                        public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                        	return R * Math.acos(Math.cos((lambda2 - lambda1)));
                                                                        }
                                                                        
                                                                        def code(R, lambda1, lambda2, phi1, phi2):
                                                                        	return R * math.acos(math.cos((lambda2 - lambda1)))
                                                                        
                                                                        function code(R, lambda1, lambda2, phi1, phi2)
                                                                        	return Float64(R * acos(cos(Float64(lambda2 - lambda1))))
                                                                        end
                                                                        
                                                                        function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                        	tmp = R * acos(cos((lambda2 - lambda1)));
                                                                        end
                                                                        
                                                                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[ArcCos[N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                                                                        
                                                                        \begin{array}{l}
                                                                        
                                                                        \\
                                                                        R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right)
                                                                        \end{array}
                                                                        
                                                                        Derivation
                                                                        1. Initial program 71.6%

                                                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                        2. Step-by-step derivation
                                                                          1. Simplified71.6%

                                                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                          2. Add Preprocessing
                                                                          3. Taylor expanded in phi2 around 0 41.8%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                          4. Taylor expanded in phi1 around 0 24.2%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                          5. Final simplification24.2%

                                                                            \[\leadsto R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right) \]
                                                                          6. Add Preprocessing

                                                                          Alternative 27: 6.6% accurate, 68.0× speedup?

                                                                          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -1.9 \cdot 10^{-143}:\\ \;\;\;\;\lambda_1 \cdot \left(-R\right)\\ \mathbf{else}:\\ \;\;\;\;\lambda_2 \cdot R\\ \end{array} \end{array} \]
                                                                          (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                           :precision binary64
                                                                           (if (<= lambda1 -1.9e-143) (* lambda1 (- R)) (* lambda2 R)))
                                                                          double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                          	double tmp;
                                                                          	if (lambda1 <= -1.9e-143) {
                                                                          		tmp = lambda1 * -R;
                                                                          	} else {
                                                                          		tmp = lambda2 * R;
                                                                          	}
                                                                          	return tmp;
                                                                          }
                                                                          
                                                                          real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                              real(8), intent (in) :: r
                                                                              real(8), intent (in) :: lambda1
                                                                              real(8), intent (in) :: lambda2
                                                                              real(8), intent (in) :: phi1
                                                                              real(8), intent (in) :: phi2
                                                                              real(8) :: tmp
                                                                              if (lambda1 <= (-1.9d-143)) then
                                                                                  tmp = lambda1 * -r
                                                                              else
                                                                                  tmp = lambda2 * r
                                                                              end if
                                                                              code = tmp
                                                                          end function
                                                                          
                                                                          public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                          	double tmp;
                                                                          	if (lambda1 <= -1.9e-143) {
                                                                          		tmp = lambda1 * -R;
                                                                          	} else {
                                                                          		tmp = lambda2 * R;
                                                                          	}
                                                                          	return tmp;
                                                                          }
                                                                          
                                                                          def code(R, lambda1, lambda2, phi1, phi2):
                                                                          	tmp = 0
                                                                          	if lambda1 <= -1.9e-143:
                                                                          		tmp = lambda1 * -R
                                                                          	else:
                                                                          		tmp = lambda2 * R
                                                                          	return tmp
                                                                          
                                                                          function code(R, lambda1, lambda2, phi1, phi2)
                                                                          	tmp = 0.0
                                                                          	if (lambda1 <= -1.9e-143)
                                                                          		tmp = Float64(lambda1 * Float64(-R));
                                                                          	else
                                                                          		tmp = Float64(lambda2 * R);
                                                                          	end
                                                                          	return tmp
                                                                          end
                                                                          
                                                                          function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                                          	tmp = 0.0;
                                                                          	if (lambda1 <= -1.9e-143)
                                                                          		tmp = lambda1 * -R;
                                                                          	else
                                                                          		tmp = lambda2 * R;
                                                                          	end
                                                                          	tmp_2 = tmp;
                                                                          end
                                                                          
                                                                          code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -1.9e-143], N[(lambda1 * (-R)), $MachinePrecision], N[(lambda2 * R), $MachinePrecision]]
                                                                          
                                                                          \begin{array}{l}
                                                                          
                                                                          \\
                                                                          \begin{array}{l}
                                                                          \mathbf{if}\;\lambda_1 \leq -1.9 \cdot 10^{-143}:\\
                                                                          \;\;\;\;\lambda_1 \cdot \left(-R\right)\\
                                                                          
                                                                          \mathbf{else}:\\
                                                                          \;\;\;\;\lambda_2 \cdot R\\
                                                                          
                                                                          
                                                                          \end{array}
                                                                          \end{array}
                                                                          
                                                                          Derivation
                                                                          1. Split input into 2 regimes
                                                                          2. if lambda1 < -1.89999999999999991e-143

                                                                            1. Initial program 64.3%

                                                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                            2. Step-by-step derivation
                                                                              1. Simplified64.3%

                                                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                              2. Add Preprocessing
                                                                              3. Taylor expanded in phi2 around 0 34.0%

                                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                              4. Taylor expanded in phi1 around 0 22.2%

                                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                              5. Taylor expanded in lambda2 around 0 6.5%

                                                                                \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right)} \]
                                                                              6. Step-by-step derivation
                                                                                1. mul-1-neg6.5%

                                                                                  \[\leadsto \color{blue}{-R \cdot \lambda_1} \]
                                                                                2. *-commutative6.5%

                                                                                  \[\leadsto -\color{blue}{\lambda_1 \cdot R} \]
                                                                                3. distribute-rgt-neg-in6.5%

                                                                                  \[\leadsto \color{blue}{\lambda_1 \cdot \left(-R\right)} \]
                                                                              7. Simplified6.5%

                                                                                \[\leadsto \color{blue}{\lambda_1 \cdot \left(-R\right)} \]

                                                                              if -1.89999999999999991e-143 < lambda1

                                                                              1. Initial program 75.6%

                                                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                              2. Step-by-step derivation
                                                                                1. Simplified75.6%

                                                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                                2. Add Preprocessing
                                                                                3. Taylor expanded in phi2 around 0 46.0%

                                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                                4. Taylor expanded in phi1 around 0 25.3%

                                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                                5. Taylor expanded in lambda2 around inf 5.3%

                                                                                  \[\leadsto \color{blue}{R \cdot \lambda_2} \]
                                                                                6. Step-by-step derivation
                                                                                  1. *-commutative5.3%

                                                                                    \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                                7. Simplified5.3%

                                                                                  \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                              3. Recombined 2 regimes into one program.
                                                                              4. Final simplification5.7%

                                                                                \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -1.9 \cdot 10^{-143}:\\ \;\;\;\;\lambda_1 \cdot \left(-R\right)\\ \mathbf{else}:\\ \;\;\;\;\lambda_2 \cdot R\\ \end{array} \]
                                                                              5. Add Preprocessing

                                                                              Alternative 28: 5.7% accurate, 122.6× speedup?

                                                                              \[\begin{array}{l} \\ R \cdot \left(\lambda_2 - \lambda_1\right) \end{array} \]
                                                                              (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                               :precision binary64
                                                                               (* R (- lambda2 lambda1)))
                                                                              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                              	return R * (lambda2 - lambda1);
                                                                              }
                                                                              
                                                                              real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                                  real(8), intent (in) :: r
                                                                                  real(8), intent (in) :: lambda1
                                                                                  real(8), intent (in) :: lambda2
                                                                                  real(8), intent (in) :: phi1
                                                                                  real(8), intent (in) :: phi2
                                                                                  code = r * (lambda2 - lambda1)
                                                                              end function
                                                                              
                                                                              public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                              	return R * (lambda2 - lambda1);
                                                                              }
                                                                              
                                                                              def code(R, lambda1, lambda2, phi1, phi2):
                                                                              	return R * (lambda2 - lambda1)
                                                                              
                                                                              function code(R, lambda1, lambda2, phi1, phi2)
                                                                              	return Float64(R * Float64(lambda2 - lambda1))
                                                                              end
                                                                              
                                                                              function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                              	tmp = R * (lambda2 - lambda1);
                                                                              end
                                                                              
                                                                              code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]
                                                                              
                                                                              \begin{array}{l}
                                                                              
                                                                              \\
                                                                              R \cdot \left(\lambda_2 - \lambda_1\right)
                                                                              \end{array}
                                                                              
                                                                              Derivation
                                                                              1. Initial program 71.6%

                                                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                              2. Step-by-step derivation
                                                                                1. Simplified71.6%

                                                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                                2. Add Preprocessing
                                                                                3. Taylor expanded in phi2 around 0 41.8%

                                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                                4. Taylor expanded in phi1 around 0 24.2%

                                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                                5. Taylor expanded in lambda2 around 0 4.3%

                                                                                  \[\leadsto R \cdot \color{blue}{\left(\lambda_2 + -1 \cdot \lambda_1\right)} \]
                                                                                6. Step-by-step derivation
                                                                                  1. neg-mul-14.3%

                                                                                    \[\leadsto R \cdot \left(\lambda_2 + \color{blue}{\left(-\lambda_1\right)}\right) \]
                                                                                  2. sub-neg4.3%

                                                                                    \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
                                                                                7. Simplified4.3%

                                                                                  \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
                                                                                8. Final simplification4.3%

                                                                                  \[\leadsto R \cdot \left(\lambda_2 - \lambda_1\right) \]
                                                                                9. Add Preprocessing

                                                                                Alternative 29: 5.3% accurate, 204.3× speedup?

                                                                                \[\begin{array}{l} \\ \lambda_2 \cdot R \end{array} \]
                                                                                (FPCore (R lambda1 lambda2 phi1 phi2) :precision binary64 (* lambda2 R))
                                                                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                                	return lambda2 * R;
                                                                                }
                                                                                
                                                                                real(8) function code(r, lambda1, lambda2, phi1, phi2)
                                                                                    real(8), intent (in) :: r
                                                                                    real(8), intent (in) :: lambda1
                                                                                    real(8), intent (in) :: lambda2
                                                                                    real(8), intent (in) :: phi1
                                                                                    real(8), intent (in) :: phi2
                                                                                    code = lambda2 * r
                                                                                end function
                                                                                
                                                                                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                                	return lambda2 * R;
                                                                                }
                                                                                
                                                                                def code(R, lambda1, lambda2, phi1, phi2):
                                                                                	return lambda2 * R
                                                                                
                                                                                function code(R, lambda1, lambda2, phi1, phi2)
                                                                                	return Float64(lambda2 * R)
                                                                                end
                                                                                
                                                                                function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                                	tmp = lambda2 * R;
                                                                                end
                                                                                
                                                                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(lambda2 * R), $MachinePrecision]
                                                                                
                                                                                \begin{array}{l}
                                                                                
                                                                                \\
                                                                                \lambda_2 \cdot R
                                                                                \end{array}
                                                                                
                                                                                Derivation
                                                                                1. Initial program 71.6%

                                                                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                                2. Step-by-step derivation
                                                                                  1. Simplified71.6%

                                                                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                                  2. Add Preprocessing
                                                                                  3. Taylor expanded in phi2 around 0 41.8%

                                                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                                  4. Taylor expanded in phi1 around 0 24.2%

                                                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                                  5. Taylor expanded in lambda2 around inf 4.9%

                                                                                    \[\leadsto \color{blue}{R \cdot \lambda_2} \]
                                                                                  6. Step-by-step derivation
                                                                                    1. *-commutative4.9%

                                                                                      \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                                  7. Simplified4.9%

                                                                                    \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                                  8. Final simplification4.9%

                                                                                    \[\leadsto \lambda_2 \cdot R \]
                                                                                  9. Add Preprocessing

                                                                                  Reproduce

                                                                                  ?
                                                                                  herbie shell --seed 2024024 
                                                                                  (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                                    :name "Spherical law of cosines"
                                                                                    :precision binary64
                                                                                    (* (acos (+ (* (sin phi1) (sin phi2)) (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))) R))