Spherical law of cosines

Percentage Accurate: 73.7% → 96.6%
Time: 39.0s
Alternatives: 25
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 25 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: 73.7% 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: 96.6% accurate, 0.4× speedup?

\[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\ \end{array} \end{array} \]
NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (if (<=
      (acos
       (+
        (* (sin phi1) (sin phi2))
        (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))
      0.0)
   (fma lambda2 R (* lambda1 (- R)))
   (*
    R
    (acos
     (fma
      (sin phi1)
      (sin phi2)
      (*
       (cos phi1)
       (*
        (cos phi2)
        (+
         (* (cos lambda1) (cos lambda2))
         (* (sin lambda1) (sin lambda2))))))))))
assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double tmp;
	if (acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) <= 0.0) {
		tmp = fma(lambda2, R, (lambda1 * -R));
	} else {
		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * (cos(phi2) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))));
	}
	return tmp;
}
R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
function code(R, lambda1, lambda2, phi1, phi2)
	tmp = 0.0
	if (acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))) <= 0.0)
		tmp = fma(lambda2, R, Float64(lambda1 * Float64(-R)));
	else
		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * Float64(cos(phi2) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))))));
	end
	return tmp
end
NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[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], 0.0], N[(lambda2 * R + N[(lambda1 * (-R)), $MachinePrecision]), $MachinePrecision], 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[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
[R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
\\
\begin{array}{l}
\mathbf{if}\;\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) \leq 0:\\
\;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\

\mathbf{else}:\\
\;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))) < 0.0

    1. Initial program 9.2%

      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
    2. Step-by-step derivation
      1. Simplified9.2%

        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
      2. Add Preprocessing
      3. Taylor expanded in phi2 around 0 9.2%

        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
      4. Taylor expanded in phi1 around 0 9.2%

        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
      5. Taylor expanded in lambda1 around inf 41.0%

        \[\leadsto R \cdot \color{blue}{\left(\lambda_1 \cdot \left(\frac{\lambda_2}{\lambda_1} - 1\right)\right)} \]
      6. Taylor expanded in lambda1 around 0 41.0%

        \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right) + R \cdot \lambda_2} \]
      7. Step-by-step derivation
        1. +-commutative41.0%

          \[\leadsto \color{blue}{R \cdot \lambda_2 + -1 \cdot \left(R \cdot \lambda_1\right)} \]
        2. *-commutative41.0%

          \[\leadsto \color{blue}{\lambda_2 \cdot R} + -1 \cdot \left(R \cdot \lambda_1\right) \]
        3. fma-define41.1%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\lambda_2, R, -1 \cdot \left(R \cdot \lambda_1\right)\right)} \]
        4. mul-1-neg41.1%

          \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{-R \cdot \lambda_1}\right) \]
        5. distribute-rgt-neg-in41.1%

          \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{R \cdot \left(-\lambda_1\right)}\right) \]
      8. Simplified41.1%

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

      if 0.0 < (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))))

      1. Initial program 81.5%

        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
      2. Simplified81.6%

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

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
        2. distribute-lft-in99.1%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
      5. Applied egg-rr99.1%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
      6. Step-by-step derivation
        1. distribute-lft-out99.1%

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

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
        3. fma-undefine99.1%

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

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
      7. Simplified99.1%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
      8. Taylor expanded in phi2 around inf 99.1%

        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
    3. Recombined 2 regimes into one program.
    4. Final simplification94.4%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 2: 96.6% accurate, 0.4× speedup?

    \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\cos^{-1} \left(t\_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \end{array} \end{array} \]
    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
    (FPCore (R lambda1 lambda2 phi1 phi2)
     :precision binary64
     (let* ((t_0 (* (sin phi1) (sin phi2))))
       (if (<=
            (acos (+ t_0 (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))
            0.0)
         (fma lambda2 R (* lambda1 (- R)))
         (*
          R
          (acos
           (+
            t_0
            (*
             (cos phi1)
             (*
              (cos phi2)
              (+
               (* (cos lambda1) (cos lambda2))
               (* (sin lambda1) (sin lambda2)))))))))))
    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
    	double t_0 = sin(phi1) * sin(phi2);
    	double tmp;
    	if (acos((t_0 + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2))))) <= 0.0) {
    		tmp = fma(lambda2, R, (lambda1 * -R));
    	} else {
    		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))));
    	}
    	return tmp;
    }
    
    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
    function code(R, lambda1, lambda2, phi1, phi2)
    	t_0 = Float64(sin(phi1) * sin(phi2))
    	tmp = 0.0
    	if (acos(Float64(t_0 + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2))))) <= 0.0)
    		tmp = fma(lambda2, R, Float64(lambda1 * Float64(-R)));
    	else
    		tmp = Float64(R * acos(Float64(t_0 + Float64(cos(phi1) * Float64(cos(phi2) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))))));
    	end
    	return tmp
    end
    
    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
    code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[ArcCos[N[(t$95$0 + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 0.0], N[(lambda2 * R + N[(lambda1 * (-R)), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(t$95$0 + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
    
    \begin{array}{l}
    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
    \\
    \begin{array}{l}
    t_0 := \sin \phi_1 \cdot \sin \phi_2\\
    \mathbf{if}\;\cos^{-1} \left(t\_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\
    \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))) < 0.0

      1. Initial program 9.2%

        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
      2. Step-by-step derivation
        1. Simplified9.2%

          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
        2. Add Preprocessing
        3. Taylor expanded in phi2 around 0 9.2%

          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
        4. Taylor expanded in phi1 around 0 9.2%

          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
        5. Taylor expanded in lambda1 around inf 41.0%

          \[\leadsto R \cdot \color{blue}{\left(\lambda_1 \cdot \left(\frac{\lambda_2}{\lambda_1} - 1\right)\right)} \]
        6. Taylor expanded in lambda1 around 0 41.0%

          \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right) + R \cdot \lambda_2} \]
        7. Step-by-step derivation
          1. +-commutative41.0%

            \[\leadsto \color{blue}{R \cdot \lambda_2 + -1 \cdot \left(R \cdot \lambda_1\right)} \]
          2. *-commutative41.0%

            \[\leadsto \color{blue}{\lambda_2 \cdot R} + -1 \cdot \left(R \cdot \lambda_1\right) \]
          3. fma-define41.1%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\lambda_2, R, -1 \cdot \left(R \cdot \lambda_1\right)\right)} \]
          4. mul-1-neg41.1%

            \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{-R \cdot \lambda_1}\right) \]
          5. distribute-rgt-neg-in41.1%

            \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{R \cdot \left(-\lambda_1\right)}\right) \]
        8. Simplified41.1%

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

        if 0.0 < (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))))

        1. Initial program 81.5%

          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
        2. Simplified81.6%

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

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
          2. distribute-lft-in99.1%

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
        5. Applied egg-rr99.1%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
        6. Step-by-step derivation
          1. distribute-lft-out99.1%

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

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
          3. fma-undefine99.1%

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

            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
        7. Simplified99.1%

          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
        8. Taylor expanded in phi1 around 0 99.1%

          \[\leadsto \color{blue}{\cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right) + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
      3. Recombined 2 regimes into one program.
      4. Final simplification94.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 3: 76.1% accurate, 0.5× speedup?

      \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \cos \left(\lambda_1 - \lambda_2\right)\\ \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot t\_0\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot t\_0\right)\right)\right)\\ \end{array} \end{array} \]
      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
      (FPCore (R lambda1 lambda2 phi1 phi2)
       :precision binary64
       (let* ((t_0 (cos (- lambda1 lambda2))))
         (if (<=
              (acos (+ (* (sin phi1) (sin phi2)) (* (* (cos phi1) (cos phi2)) t_0)))
              0.0)
           (fma lambda2 R (* lambda1 (- R)))
           (*
            R
            (acos (fma (sin phi1) (sin phi2) (* (cos phi1) (* (cos phi2) t_0))))))))
      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
      double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
      	double t_0 = cos((lambda1 - lambda2));
      	double tmp;
      	if (acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * t_0))) <= 0.0) {
      		tmp = fma(lambda2, R, (lambda1 * -R));
      	} else {
      		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * (cos(phi2) * t_0))));
      	}
      	return tmp;
      }
      
      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
      function code(R, lambda1, lambda2, phi1, phi2)
      	t_0 = cos(Float64(lambda1 - lambda2))
      	tmp = 0.0
      	if (acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * t_0))) <= 0.0)
      		tmp = fma(lambda2, R, Float64(lambda1 * Float64(-R)));
      	else
      		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * Float64(cos(phi2) * t_0)))));
      	end
      	return tmp
      end
      
      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
      code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 0.0], N[(lambda2 * R + N[(lambda1 * (-R)), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
      \\
      \begin{array}{l}
      t_0 := \cos \left(\lambda_1 - \lambda_2\right)\\
      \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot t\_0\right) \leq 0:\\
      \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot t\_0\right)\right)\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))) < 0.0

        1. Initial program 9.2%

          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
        2. Step-by-step derivation
          1. Simplified9.2%

            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
          2. Add Preprocessing
          3. Taylor expanded in phi2 around 0 9.2%

            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
          4. Taylor expanded in phi1 around 0 9.2%

            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
          5. Taylor expanded in lambda1 around inf 41.0%

            \[\leadsto R \cdot \color{blue}{\left(\lambda_1 \cdot \left(\frac{\lambda_2}{\lambda_1} - 1\right)\right)} \]
          6. Taylor expanded in lambda1 around 0 41.0%

            \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right) + R \cdot \lambda_2} \]
          7. Step-by-step derivation
            1. +-commutative41.0%

              \[\leadsto \color{blue}{R \cdot \lambda_2 + -1 \cdot \left(R \cdot \lambda_1\right)} \]
            2. *-commutative41.0%

              \[\leadsto \color{blue}{\lambda_2 \cdot R} + -1 \cdot \left(R \cdot \lambda_1\right) \]
            3. fma-define41.1%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\lambda_2, R, -1 \cdot \left(R \cdot \lambda_1\right)\right)} \]
            4. mul-1-neg41.1%

              \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{-R \cdot \lambda_1}\right) \]
            5. distribute-rgt-neg-in41.1%

              \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{R \cdot \left(-\lambda_1\right)}\right) \]
          8. Simplified41.1%

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

          if 0.0 < (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))))

          1. Initial program 81.5%

            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
          2. Simplified81.6%

            \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
          3. Add Preprocessing
        3. Recombined 2 regimes into one program.
        4. Final simplification78.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\\ \end{array} \]
        5. Add Preprocessing

        Alternative 4: 76.1% accurate, 0.5× speedup?

        \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ t_1 := \cos \phi_1 \cdot \cos \phi_2\\ \mathbf{if}\;\cos^{-1} \left(t\_0 + t\_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t\_1, \cos \left(\lambda_2 - \lambda_1\right), t\_0\right)\right)\\ \end{array} \end{array} \]
        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
        (FPCore (R lambda1 lambda2 phi1 phi2)
         :precision binary64
         (let* ((t_0 (* (sin phi1) (sin phi2))) (t_1 (* (cos phi1) (cos phi2))))
           (if (<= (acos (+ t_0 (* t_1 (cos (- lambda1 lambda2))))) 0.0)
             (fma lambda2 R (* lambda1 (- R)))
             (* R (acos (fma t_1 (cos (- lambda2 lambda1)) t_0))))))
        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
        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 (acos((t_0 + (t_1 * cos((lambda1 - lambda2))))) <= 0.0) {
        		tmp = fma(lambda2, R, (lambda1 * -R));
        	} else {
        		tmp = R * acos(fma(t_1, cos((lambda2 - lambda1)), t_0));
        	}
        	return tmp;
        }
        
        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
        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 (acos(Float64(t_0 + Float64(t_1 * cos(Float64(lambda1 - lambda2))))) <= 0.0)
        		tmp = fma(lambda2, R, Float64(lambda1 * Float64(-R)));
        	else
        		tmp = Float64(R * acos(fma(t_1, cos(Float64(lambda2 - lambda1)), t_0)));
        	end
        	return tmp
        end
        
        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
        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[ArcCos[N[(t$95$0 + N[(t$95$1 * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 0.0], N[(lambda2 * R + N[(lambda1 * (-R)), $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(t$95$1 * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
        
        \begin{array}{l}
        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
        \\
        \begin{array}{l}
        t_0 := \sin \phi_1 \cdot \sin \phi_2\\
        t_1 := \cos \phi_1 \cdot \cos \phi_2\\
        \mathbf{if}\;\cos^{-1} \left(t\_0 + t\_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\
        \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(t\_1, \cos \left(\lambda_2 - \lambda_1\right), t\_0\right)\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))) < 0.0

          1. Initial program 9.2%

            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
          2. Step-by-step derivation
            1. Simplified9.2%

              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
            2. Add Preprocessing
            3. Taylor expanded in phi2 around 0 9.2%

              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
            4. Taylor expanded in phi1 around 0 9.2%

              \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
            5. Taylor expanded in lambda1 around inf 41.0%

              \[\leadsto R \cdot \color{blue}{\left(\lambda_1 \cdot \left(\frac{\lambda_2}{\lambda_1} - 1\right)\right)} \]
            6. Taylor expanded in lambda1 around 0 41.0%

              \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right) + R \cdot \lambda_2} \]
            7. Step-by-step derivation
              1. +-commutative41.0%

                \[\leadsto \color{blue}{R \cdot \lambda_2 + -1 \cdot \left(R \cdot \lambda_1\right)} \]
              2. *-commutative41.0%

                \[\leadsto \color{blue}{\lambda_2 \cdot R} + -1 \cdot \left(R \cdot \lambda_1\right) \]
              3. fma-define41.1%

                \[\leadsto \color{blue}{\mathsf{fma}\left(\lambda_2, R, -1 \cdot \left(R \cdot \lambda_1\right)\right)} \]
              4. mul-1-neg41.1%

                \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{-R \cdot \lambda_1}\right) \]
              5. distribute-rgt-neg-in41.1%

                \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{R \cdot \left(-\lambda_1\right)}\right) \]
            8. Simplified41.1%

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

            if 0.0 < (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))))

            1. Initial program 81.5%

              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
            2. Step-by-step derivation
              1. Simplified81.6%

                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
              2. Add Preprocessing
            3. Recombined 2 regimes into one program.
            4. Final simplification78.2%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)\\ \end{array} \]
            5. Add Preprocessing

            Alternative 5: 76.1% accurate, 0.5× speedup?

            \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\\ \mathbf{if}\;t\_0 \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0 \cdot R\\ \end{array} \end{array} \]
            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
            (FPCore (R lambda1 lambda2 phi1 phi2)
             :precision binary64
             (let* ((t_0
                     (acos
                      (+
                       (* (sin phi1) (sin phi2))
                       (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2)))))))
               (if (<= t_0 0.0) (fma lambda2 R (* lambda1 (- R))) (* t_0 R))))
            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
            	double t_0 = acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos((lambda1 - lambda2)))));
            	double tmp;
            	if (t_0 <= 0.0) {
            		tmp = fma(lambda2, R, (lambda1 * -R));
            	} else {
            		tmp = t_0 * R;
            	}
            	return tmp;
            }
            
            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
            function code(R, lambda1, lambda2, phi1, phi2)
            	t_0 = acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(Float64(lambda1 - lambda2)))))
            	tmp = 0.0
            	if (t_0 <= 0.0)
            		tmp = fma(lambda2, R, Float64(lambda1 * Float64(-R)));
            	else
            		tmp = Float64(t_0 * R);
            	end
            	return tmp
            end
            
            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
            code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = 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]}, If[LessEqual[t$95$0, 0.0], N[(lambda2 * R + N[(lambda1 * (-R)), $MachinePrecision]), $MachinePrecision], N[(t$95$0 * R), $MachinePrecision]]]
            
            \begin{array}{l}
            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
            \\
            \begin{array}{l}
            t_0 := \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{if}\;t\_0 \leq 0:\\
            \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;t\_0 \cdot R\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2))))) < 0.0

              1. Initial program 9.2%

                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
              2. Step-by-step derivation
                1. Simplified9.2%

                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around 0 9.2%

                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                4. Taylor expanded in phi1 around 0 9.2%

                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                5. Taylor expanded in lambda1 around inf 41.0%

                  \[\leadsto R \cdot \color{blue}{\left(\lambda_1 \cdot \left(\frac{\lambda_2}{\lambda_1} - 1\right)\right)} \]
                6. Taylor expanded in lambda1 around 0 41.0%

                  \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right) + R \cdot \lambda_2} \]
                7. Step-by-step derivation
                  1. +-commutative41.0%

                    \[\leadsto \color{blue}{R \cdot \lambda_2 + -1 \cdot \left(R \cdot \lambda_1\right)} \]
                  2. *-commutative41.0%

                    \[\leadsto \color{blue}{\lambda_2 \cdot R} + -1 \cdot \left(R \cdot \lambda_1\right) \]
                  3. fma-define41.1%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\lambda_2, R, -1 \cdot \left(R \cdot \lambda_1\right)\right)} \]
                  4. mul-1-neg41.1%

                    \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{-R \cdot \lambda_1}\right) \]
                  5. distribute-rgt-neg-in41.1%

                    \[\leadsto \mathsf{fma}\left(\lambda_2, R, \color{blue}{R \cdot \left(-\lambda_1\right)}\right) \]
                8. Simplified41.1%

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

                if 0.0 < (acos.f64 (+.f64 (*.f64 (sin.f64 phi1) (sin.f64 phi2)) (*.f64 (*.f64 (cos.f64 phi1) (cos.f64 phi2)) (cos.f64 (-.f64 lambda1 lambda2)))))

                1. Initial program 81.5%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Add Preprocessing
              3. Recombined 2 regimes into one program.
              4. Final simplification78.2%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \leq 0:\\ \;\;\;\;\mathsf{fma}\left(\lambda_2, R, \lambda_1 \cdot \left(-R\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R\\ \end{array} \]
              5. Add Preprocessing

              Alternative 6: 83.4% accurate, 0.7× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -0.0054:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\\ \mathbf{elif}\;\phi_1 \leq 1.36 \cdot 10^{-61}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right)\\ \end{array} \end{array} \]
              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
              (FPCore (R lambda1 lambda2 phi1 phi2)
               :precision binary64
               (if (<= phi1 -0.0054)
                 (*
                  R
                  (acos
                   (fma
                    (sin phi1)
                    (sin phi2)
                    (* (cos phi1) (* (cos phi2) (cos (- lambda1 lambda2)))))))
                 (if (<= phi1 1.36e-61)
                   (*
                    R
                    (acos
                     (fma
                      (sin phi1)
                      (sin phi2)
                      (*
                       (cos phi2)
                       (+
                        (* (cos lambda1) (cos lambda2))
                        (* (sin lambda1) (sin lambda2)))))))
                   (*
                    R
                    (log
                     (exp
                      (acos
                       (fma
                        (cos phi1)
                        (* (cos phi2) (cos (- lambda2 lambda1)))
                        (* (sin phi1) (sin phi2))))))))))
              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
              	double tmp;
              	if (phi1 <= -0.0054) {
              		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * (cos(phi2) * cos((lambda1 - lambda2))))));
              	} else if (phi1 <= 1.36e-61) {
              		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi2) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2))))));
              	} else {
              		tmp = R * log(exp(acos(fma(cos(phi1), (cos(phi2) * cos((lambda2 - lambda1))), (sin(phi1) * sin(phi2))))));
              	}
              	return tmp;
              }
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -0.0054)
              		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * Float64(cos(phi2) * cos(Float64(lambda1 - lambda2)))))));
              	elseif (phi1 <= 1.36e-61)
              		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi2) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2)))))));
              	else
              		tmp = Float64(R * log(exp(acos(fma(cos(phi1), Float64(cos(phi2) * cos(Float64(lambda2 - lambda1))), Float64(sin(phi1) * sin(phi2)))))));
              	end
              	return tmp
              end
              
              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
              code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi1, -0.0054], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi1, 1.36e-61], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi2], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[Log[N[Exp[N[ArcCos[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]), $MachinePrecision]]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -0.0054:\\
              \;\;\;\;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_1 \leq 1.36 \cdot 10^{-61}:\\
              \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;R \cdot \log \left(e^{\cos^{-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)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if phi1 < -0.0054000000000000003

                1. Initial program 81.9%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Simplified82.0%

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

                if -0.0054000000000000003 < phi1 < 1.35999999999999995e-61

                1. Initial program 66.4%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Simplified66.4%

                  \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                3. Add Preprocessing
                4. Step-by-step derivation
                  1. cos-diff83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                  2. distribute-lft-in83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                5. Applied egg-rr83.9%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2\right) + \cos \phi_2 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                6. Step-by-step derivation
                  1. distribute-lft-out83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                  2. *-commutative83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\right) \cdot R \]
                  3. fma-undefine83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_1 \cdot \sin \lambda_2\right)}\right)\right)\right) \cdot R \]
                  4. *-commutative83.9%

                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right)\right)\right)\right) \cdot R \]
                7. Simplified83.9%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \mathsf{fma}\left(\cos \lambda_2, \cos \lambda_1, \sin \lambda_2 \cdot \sin \lambda_1\right)\right)}\right)\right) \cdot R \]
                8. Taylor expanded in phi2 around inf 83.9%

                  \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)}\right)\right) \cdot R \]
                9. Taylor expanded in phi1 around 0 83.9%

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

                if 1.35999999999999995e-61 < phi1

                1. Initial program 81.2%

                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                2. Step-by-step derivation
                  1. Simplified81.3%

                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. add-log-exp81.3%

                      \[\leadsto R \cdot \color{blue}{\log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right)} \]
                    2. cos-diff95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1}, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    3. *-commutative95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2} + \sin \lambda_2 \cdot \sin \lambda_1, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    4. *-commutative95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \lambda_1 \cdot \cos \lambda_2 + \color{blue}{\sin \lambda_1 \cdot \sin \lambda_2}, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    5. cos-diff81.3%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \color{blue}{\cos \left(\lambda_1 - \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    6. fma-define81.3%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \color{blue}{\left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right) + \sin \phi_1 \cdot \sin \phi_2\right)}}\right) \]
                    7. associate-*r*81.3%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)} + \sin \phi_1 \cdot \sin \phi_2\right)}\right) \]
                    8. fma-define81.3%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \color{blue}{\left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}}\right) \]
                    9. cos-diff95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    10. *-commutative95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \left(\color{blue}{\cos \lambda_2 \cdot \cos \lambda_1} + \sin \lambda_1 \cdot \sin \lambda_2\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    11. *-commutative95.6%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \left(\cos \lambda_2 \cdot \cos \lambda_1 + \color{blue}{\sin \lambda_2 \cdot \sin \lambda_1}\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                    12. cos-diff81.3%

                      \[\leadsto R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)}, \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right) \]
                  4. Applied egg-rr81.3%

                    \[\leadsto R \cdot \color{blue}{\log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right)} \]
                3. Recombined 3 regimes into one program.
                4. Final simplification82.5%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -0.0054:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\\ \mathbf{elif}\;\phi_1 \leq 1.36 \cdot 10^{-61}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_2 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \log \left(e^{\cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1, \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)}\right)\\ \end{array} \]
                5. Add Preprocessing

                Alternative 7: 72.8% accurate, 1.0× speedup?

                \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ t_1 := \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\\ \mathbf{if}\;\phi_2 \leq -0.066:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;\phi_2 \leq 8.5 \cdot 10^{-10}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 23500000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;\phi_2 \leq 4.65 \cdot 10^{+27}:\\ \;\;\;\;R \cdot \cos^{-1} t\_1\\ \mathbf{elif}\;\phi_2 \leq 7.8 \cdot 10^{+94} \lor \neg \left(\phi_2 \leq 2.8 \cdot 10^{+118}\right):\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_1 + \phi_1 \cdot \sin \phi_2\right)\\ \end{array} \end{array} \]
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                (FPCore (R lambda1 lambda2 phi1 phi2)
                 :precision binary64
                 (let* ((t_0
                         (*
                          R
                          (acos
                           (+
                            (* (sin phi1) (sin phi2))
                            (* (* (cos phi1) (cos phi2)) (cos lambda1))))))
                        (t_1 (* (cos phi2) (cos (- lambda2 lambda1)))))
                   (if (<= phi2 -0.066)
                     t_0
                     (if (<= phi2 8.5e-10)
                       (*
                        R
                        (acos
                         (*
                          (cos phi1)
                          (+
                           (* (cos lambda1) (cos lambda2))
                           (* (sin lambda1) (sin lambda2))))))
                       (if (<= phi2 23500000.0)
                         t_0
                         (if (<= phi2 4.65e+27)
                           (* R (acos t_1))
                           (if (or (<= phi2 7.8e+94) (not (<= phi2 2.8e+118)))
                             t_0
                             (* R (acos (+ t_1 (* phi1 (sin phi2))))))))))))
                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                	double t_0 = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda1))));
                	double t_1 = cos(phi2) * cos((lambda2 - lambda1));
                	double tmp;
                	if (phi2 <= -0.066) {
                		tmp = t_0;
                	} else if (phi2 <= 8.5e-10) {
                		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                	} else if (phi2 <= 23500000.0) {
                		tmp = t_0;
                	} else if (phi2 <= 4.65e+27) {
                		tmp = R * acos(t_1);
                	} else if ((phi2 <= 7.8e+94) || !(phi2 <= 2.8e+118)) {
                		tmp = t_0;
                	} else {
                		tmp = R * acos((t_1 + (phi1 * sin(phi2))));
                	}
                	return tmp;
                }
                
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                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) :: t_1
                    real(8) :: tmp
                    t_0 = r * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda1))))
                    t_1 = cos(phi2) * cos((lambda2 - lambda1))
                    if (phi2 <= (-0.066d0)) then
                        tmp = t_0
                    else if (phi2 <= 8.5d-10) then
                        tmp = r * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))
                    else if (phi2 <= 23500000.0d0) then
                        tmp = t_0
                    else if (phi2 <= 4.65d+27) then
                        tmp = r * acos(t_1)
                    else if ((phi2 <= 7.8d+94) .or. (.not. (phi2 <= 2.8d+118))) then
                        tmp = t_0
                    else
                        tmp = r * acos((t_1 + (phi1 * sin(phi2))))
                    end if
                    code = tmp
                end function
                
                assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                	double t_0 = R * Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos(lambda1))));
                	double t_1 = Math.cos(phi2) * Math.cos((lambda2 - lambda1));
                	double tmp;
                	if (phi2 <= -0.066) {
                		tmp = t_0;
                	} else if (phi2 <= 8.5e-10) {
                		tmp = R * Math.acos((Math.cos(phi1) * ((Math.cos(lambda1) * Math.cos(lambda2)) + (Math.sin(lambda1) * Math.sin(lambda2)))));
                	} else if (phi2 <= 23500000.0) {
                		tmp = t_0;
                	} else if (phi2 <= 4.65e+27) {
                		tmp = R * Math.acos(t_1);
                	} else if ((phi2 <= 7.8e+94) || !(phi2 <= 2.8e+118)) {
                		tmp = t_0;
                	} else {
                		tmp = R * Math.acos((t_1 + (phi1 * Math.sin(phi2))));
                	}
                	return tmp;
                }
                
                [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                def code(R, lambda1, lambda2, phi1, phi2):
                	t_0 = R * math.acos(((math.sin(phi1) * math.sin(phi2)) + ((math.cos(phi1) * math.cos(phi2)) * math.cos(lambda1))))
                	t_1 = math.cos(phi2) * math.cos((lambda2 - lambda1))
                	tmp = 0
                	if phi2 <= -0.066:
                		tmp = t_0
                	elif phi2 <= 8.5e-10:
                		tmp = R * math.acos((math.cos(phi1) * ((math.cos(lambda1) * math.cos(lambda2)) + (math.sin(lambda1) * math.sin(lambda2)))))
                	elif phi2 <= 23500000.0:
                		tmp = t_0
                	elif phi2 <= 4.65e+27:
                		tmp = R * math.acos(t_1)
                	elif (phi2 <= 7.8e+94) or not (phi2 <= 2.8e+118):
                		tmp = t_0
                	else:
                		tmp = R * math.acos((t_1 + (phi1 * math.sin(phi2))))
                	return tmp
                
                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                function code(R, lambda1, lambda2, phi1, phi2)
                	t_0 = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(Float64(cos(phi1) * cos(phi2)) * cos(lambda1)))))
                	t_1 = Float64(cos(phi2) * cos(Float64(lambda2 - lambda1)))
                	tmp = 0.0
                	if (phi2 <= -0.066)
                		tmp = t_0;
                	elseif (phi2 <= 8.5e-10)
                		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))));
                	elseif (phi2 <= 23500000.0)
                		tmp = t_0;
                	elseif (phi2 <= 4.65e+27)
                		tmp = Float64(R * acos(t_1));
                	elseif ((phi2 <= 7.8e+94) || !(phi2 <= 2.8e+118))
                		tmp = t_0;
                	else
                		tmp = Float64(R * acos(Float64(t_1 + Float64(phi1 * sin(phi2)))));
                	end
                	return tmp
                end
                
                R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                	t_0 = R * acos(((sin(phi1) * sin(phi2)) + ((cos(phi1) * cos(phi2)) * cos(lambda1))));
                	t_1 = cos(phi2) * cos((lambda2 - lambda1));
                	tmp = 0.0;
                	if (phi2 <= -0.066)
                		tmp = t_0;
                	elseif (phi2 <= 8.5e-10)
                		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                	elseif (phi2 <= 23500000.0)
                		tmp = t_0;
                	elseif (phi2 <= 4.65e+27)
                		tmp = R * acos(t_1);
                	elseif ((phi2 <= 7.8e+94) || ~((phi2 <= 2.8e+118)))
                		tmp = t_0;
                	else
                		tmp = R * acos((t_1 + (phi1 * sin(phi2))));
                	end
                	tmp_2 = tmp;
                end
                
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = 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[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[phi2, -0.066], t$95$0, If[LessEqual[phi2, 8.5e-10], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 23500000.0], t$95$0, If[LessEqual[phi2, 4.65e+27], N[(R * N[ArcCos[t$95$1], $MachinePrecision]), $MachinePrecision], If[Or[LessEqual[phi2, 7.8e+94], N[Not[LessEqual[phi2, 2.8e+118]], $MachinePrecision]], t$95$0, N[(R * N[ArcCos[N[(t$95$1 + N[(phi1 * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]]]]
                
                \begin{array}{l}
                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                \\
                \begin{array}{l}
                t_0 := R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\
                t_1 := \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\\
                \mathbf{if}\;\phi_2 \leq -0.066:\\
                \;\;\;\;t\_0\\
                
                \mathbf{elif}\;\phi_2 \leq 8.5 \cdot 10^{-10}:\\
                \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                
                \mathbf{elif}\;\phi_2 \leq 23500000:\\
                \;\;\;\;t\_0\\
                
                \mathbf{elif}\;\phi_2 \leq 4.65 \cdot 10^{+27}:\\
                \;\;\;\;R \cdot \cos^{-1} t\_1\\
                
                \mathbf{elif}\;\phi_2 \leq 7.8 \cdot 10^{+94} \lor \neg \left(\phi_2 \leq 2.8 \cdot 10^{+118}\right):\\
                \;\;\;\;t\_0\\
                
                \mathbf{else}:\\
                \;\;\;\;R \cdot \cos^{-1} \left(t\_1 + \phi_1 \cdot \sin \phi_2\right)\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 4 regimes
                2. if phi2 < -0.066000000000000003 or 8.4999999999999996e-10 < phi2 < 2.35e7 or 4.65000000000000021e27 < phi2 < 7.79999999999999971e94 or 2.79999999999999986e118 < phi2

                  1. Initial program 82.0%

                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                  2. Add Preprocessing
                  3. Taylor expanded in lambda2 around 0 57.0%

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

                  if -0.066000000000000003 < phi2 < 8.4999999999999996e-10

                  1. Initial program 68.7%

                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                  2. Step-by-step derivation
                    1. Simplified68.7%

                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                    2. Add Preprocessing
                    3. Taylor expanded in phi2 around 0 67.1%

                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                    4. Step-by-step derivation
                      1. cos-diff82.9%

                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                      2. +-commutative82.9%

                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                      3. *-commutative82.9%

                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                      4. *-commutative82.9%

                        \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                    5. Applied egg-rr82.9%

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

                    if 2.35e7 < phi2 < 4.65000000000000021e27

                    1. Initial program 98.8%

                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                    2. Step-by-step derivation
                      1. Simplified98.8%

                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                      2. Add Preprocessing
                      3. Taylor expanded in phi1 around 0 82.0%

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

                      if 7.79999999999999971e94 < phi2 < 2.79999999999999986e118

                      1. Initial program 80.1%

                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                      2. Step-by-step derivation
                        1. Simplified80.1%

                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                        2. Add Preprocessing
                        3. Taylor expanded in phi1 around 0 74.2%

                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_1 \cdot \sin \phi_2 + \cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                      3. Recombined 4 regimes into one program.
                      4. Final simplification70.8%

                        \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.066:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\phi_2 \leq 8.5 \cdot 10^{-10}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 23500000:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\phi_2 \leq 4.65 \cdot 10^{+27}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 7.8 \cdot 10^{+94} \lor \neg \left(\phi_2 \leq 2.8 \cdot 10^{+118}\right):\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right) + \phi_1 \cdot \sin \phi_2\right)\\ \end{array} \]
                      5. Add Preprocessing

                      Alternative 8: 74.7% accurate, 1.0× speedup?

                      \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\ \end{array} \end{array} \]
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      (FPCore (R lambda1 lambda2 phi1 phi2)
                       :precision binary64
                       (let* ((t_0 (* (sin phi1) (sin phi2))))
                         (if (<= lambda2 -4.1e+54)
                           (*
                            R
                            (acos
                             (*
                              (cos phi1)
                              (+ (* (cos lambda1) (cos lambda2)) (* (sin lambda1) (sin lambda2))))))
                           (if (<= lambda2 1.28e-18)
                             (* R (acos (+ t_0 (* (cos phi1) (* (cos phi2) (cos lambda1))))))
                             (* R (acos (+ t_0 (* (cos phi1) (* (cos phi2) (cos lambda2))))))))))
                      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                      double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                      	double t_0 = sin(phi1) * sin(phi2);
                      	double tmp;
                      	if (lambda2 <= -4.1e+54) {
                      		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                      	} else if (lambda2 <= 1.28e-18) {
                      		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda1)))));
                      	} else {
                      		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))));
                      	}
                      	return tmp;
                      }
                      
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      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 (lambda2 <= (-4.1d+54)) then
                              tmp = r * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))
                          else if (lambda2 <= 1.28d-18) then
                              tmp = r * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda1)))))
                          else
                              tmp = r * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))))
                          end if
                          code = tmp
                      end function
                      
                      assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                      assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                      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 (lambda2 <= -4.1e+54) {
                      		tmp = R * Math.acos((Math.cos(phi1) * ((Math.cos(lambda1) * Math.cos(lambda2)) + (Math.sin(lambda1) * Math.sin(lambda2)))));
                      	} else if (lambda2 <= 1.28e-18) {
                      		tmp = R * Math.acos((t_0 + (Math.cos(phi1) * (Math.cos(phi2) * Math.cos(lambda1)))));
                      	} else {
                      		tmp = R * Math.acos((t_0 + (Math.cos(phi1) * (Math.cos(phi2) * Math.cos(lambda2)))));
                      	}
                      	return tmp;
                      }
                      
                      [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                      [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                      def code(R, lambda1, lambda2, phi1, phi2):
                      	t_0 = math.sin(phi1) * math.sin(phi2)
                      	tmp = 0
                      	if lambda2 <= -4.1e+54:
                      		tmp = R * math.acos((math.cos(phi1) * ((math.cos(lambda1) * math.cos(lambda2)) + (math.sin(lambda1) * math.sin(lambda2)))))
                      	elif lambda2 <= 1.28e-18:
                      		tmp = R * math.acos((t_0 + (math.cos(phi1) * (math.cos(phi2) * math.cos(lambda1)))))
                      	else:
                      		tmp = R * math.acos((t_0 + (math.cos(phi1) * (math.cos(phi2) * math.cos(lambda2)))))
                      	return tmp
                      
                      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                      function code(R, lambda1, lambda2, phi1, phi2)
                      	t_0 = Float64(sin(phi1) * sin(phi2))
                      	tmp = 0.0
                      	if (lambda2 <= -4.1e+54)
                      		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))));
                      	elseif (lambda2 <= 1.28e-18)
                      		tmp = Float64(R * acos(Float64(t_0 + Float64(cos(phi1) * Float64(cos(phi2) * cos(lambda1))))));
                      	else
                      		tmp = Float64(R * acos(Float64(t_0 + Float64(cos(phi1) * Float64(cos(phi2) * cos(lambda2))))));
                      	end
                      	return tmp
                      end
                      
                      R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                      R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                      function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                      	t_0 = sin(phi1) * sin(phi2);
                      	tmp = 0.0;
                      	if (lambda2 <= -4.1e+54)
                      		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                      	elseif (lambda2 <= 1.28e-18)
                      		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda1)))));
                      	else
                      		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))));
                      	end
                      	tmp_2 = tmp;
                      end
                      
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                      code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[lambda2, -4.1e+54], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[lambda2, 1.28e-18], 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], N[(R * N[ArcCos[N[(t$95$0 + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                      
                      \begin{array}{l}
                      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                      \\
                      \begin{array}{l}
                      t_0 := \sin \phi_1 \cdot \sin \phi_2\\
                      \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\
                      \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                      
                      \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\
                      \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_1\right)\right)\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\
                      
                      
                      \end{array}
                      \end{array}
                      
                      Derivation
                      1. Split input into 3 regimes
                      2. if lambda2 < -4.09999999999999967e54

                        1. Initial program 64.7%

                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                        2. Step-by-step derivation
                          1. Simplified64.7%

                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                          2. Add Preprocessing
                          3. Taylor expanded in phi2 around 0 41.7%

                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                          4. Step-by-step derivation
                            1. cos-diff57.6%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                            2. +-commutative57.6%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                            3. *-commutative57.6%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                            4. *-commutative57.6%

                              \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                          5. Applied egg-rr57.6%

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

                          if -4.09999999999999967e54 < lambda2 < 1.27999999999999993e-18

                          1. Initial program 81.7%

                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                          2. Add Preprocessing
                          3. Taylor expanded in lambda2 around 0 79.2%

                            \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \lambda_1 \cdot \left(\cos \phi_1 \cdot \cos \phi_2\right)}\right) \cdot R \]
                          4. Step-by-step derivation
                            1. *-commutative79.2%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1}\right) \cdot R \]
                            2. associate-*r*79.2%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right) \cdot R \]
                          5. Simplified79.2%

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

                          if 1.27999999999999993e-18 < lambda2

                          1. Initial program 69.4%

                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                          2. Add Preprocessing
                          3. Taylor expanded in lambda1 around 0 69.3%

                            \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_2\right)\right)}\right) \cdot R \]
                          4. Step-by-step derivation
                            1. cos-neg69.3%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\cos \lambda_2}\right)\right) \cdot R \]
                            2. *-commutative69.3%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_2\right)}\right) \cdot R \]
                          5. Simplified69.3%

                            \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \phi_1 \cdot \left(\cos \lambda_2 \cdot \cos \phi_2\right)}\right) \cdot R \]
                        3. Recombined 3 regimes into one program.
                        4. Final simplification72.7%

                          \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\ \end{array} \]
                        5. Add Preprocessing

                        Alternative 9: 74.7% accurate, 1.0× speedup?

                        \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \sin \phi_1 \cdot \sin \phi_2\\ \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\ \end{array} \end{array} \]
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        (FPCore (R lambda1 lambda2 phi1 phi2)
                         :precision binary64
                         (let* ((t_0 (* (sin phi1) (sin phi2))))
                           (if (<= lambda2 -4.1e+54)
                             (*
                              R
                              (acos
                               (*
                                (cos phi1)
                                (+ (* (cos lambda1) (cos lambda2)) (* (sin lambda1) (sin lambda2))))))
                             (if (<= lambda2 1.28e-18)
                               (* R (acos (+ t_0 (* (* (cos phi1) (cos phi2)) (cos lambda1)))))
                               (* R (acos (+ t_0 (* (cos phi1) (* (cos phi2) (cos lambda2))))))))))
                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                        	double t_0 = sin(phi1) * sin(phi2);
                        	double tmp;
                        	if (lambda2 <= -4.1e+54) {
                        		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                        	} else if (lambda2 <= 1.28e-18) {
                        		tmp = R * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda1))));
                        	} else {
                        		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))));
                        	}
                        	return tmp;
                        }
                        
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        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 (lambda2 <= (-4.1d+54)) then
                                tmp = r * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))
                            else if (lambda2 <= 1.28d-18) then
                                tmp = r * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda1))))
                            else
                                tmp = r * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))))
                            end if
                            code = tmp
                        end function
                        
                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                        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 (lambda2 <= -4.1e+54) {
                        		tmp = R * Math.acos((Math.cos(phi1) * ((Math.cos(lambda1) * Math.cos(lambda2)) + (Math.sin(lambda1) * Math.sin(lambda2)))));
                        	} else if (lambda2 <= 1.28e-18) {
                        		tmp = R * Math.acos((t_0 + ((Math.cos(phi1) * Math.cos(phi2)) * Math.cos(lambda1))));
                        	} else {
                        		tmp = R * Math.acos((t_0 + (Math.cos(phi1) * (Math.cos(phi2) * Math.cos(lambda2)))));
                        	}
                        	return tmp;
                        }
                        
                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                        def code(R, lambda1, lambda2, phi1, phi2):
                        	t_0 = math.sin(phi1) * math.sin(phi2)
                        	tmp = 0
                        	if lambda2 <= -4.1e+54:
                        		tmp = R * math.acos((math.cos(phi1) * ((math.cos(lambda1) * math.cos(lambda2)) + (math.sin(lambda1) * math.sin(lambda2)))))
                        	elif lambda2 <= 1.28e-18:
                        		tmp = R * math.acos((t_0 + ((math.cos(phi1) * math.cos(phi2)) * math.cos(lambda1))))
                        	else:
                        		tmp = R * math.acos((t_0 + (math.cos(phi1) * (math.cos(phi2) * math.cos(lambda2)))))
                        	return tmp
                        
                        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                        function code(R, lambda1, lambda2, phi1, phi2)
                        	t_0 = Float64(sin(phi1) * sin(phi2))
                        	tmp = 0.0
                        	if (lambda2 <= -4.1e+54)
                        		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))));
                        	elseif (lambda2 <= 1.28e-18)
                        		tmp = Float64(R * acos(Float64(t_0 + Float64(Float64(cos(phi1) * cos(phi2)) * cos(lambda1)))));
                        	else
                        		tmp = Float64(R * acos(Float64(t_0 + Float64(cos(phi1) * Float64(cos(phi2) * cos(lambda2))))));
                        	end
                        	return tmp
                        end
                        
                        R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                        R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                        function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                        	t_0 = sin(phi1) * sin(phi2);
                        	tmp = 0.0;
                        	if (lambda2 <= -4.1e+54)
                        		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                        	elseif (lambda2 <= 1.28e-18)
                        		tmp = R * acos((t_0 + ((cos(phi1) * cos(phi2)) * cos(lambda1))));
                        	else
                        		tmp = R * acos((t_0 + (cos(phi1) * (cos(phi2) * cos(lambda2)))));
                        	end
                        	tmp_2 = tmp;
                        end
                        
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[lambda2, -4.1e+54], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[lambda2, 1.28e-18], N[(R * N[ArcCos[N[(t$95$0 + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(t$95$0 + N[(N[Cos[phi1], $MachinePrecision] * N[(N[Cos[phi2], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
                        
                        \begin{array}{l}
                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                        \\
                        \begin{array}{l}
                        t_0 := \sin \phi_1 \cdot \sin \phi_2\\
                        \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                        
                        \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\
                        
                        \mathbf{else}:\\
                        \;\;\;\;R \cdot \cos^{-1} \left(t\_0 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\
                        
                        
                        \end{array}
                        \end{array}
                        
                        Derivation
                        1. Split input into 3 regimes
                        2. if lambda2 < -4.09999999999999967e54

                          1. Initial program 64.7%

                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                          2. Step-by-step derivation
                            1. Simplified64.7%

                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                            2. Add Preprocessing
                            3. Taylor expanded in phi2 around 0 41.7%

                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                            4. Step-by-step derivation
                              1. cos-diff57.6%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                              2. +-commutative57.6%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                              3. *-commutative57.6%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                              4. *-commutative57.6%

                                \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                            5. Applied egg-rr57.6%

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

                            if -4.09999999999999967e54 < lambda2 < 1.27999999999999993e-18

                            1. Initial program 81.7%

                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                            2. Add Preprocessing
                            3. Taylor expanded in lambda2 around 0 79.2%

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

                            if 1.27999999999999993e-18 < lambda2

                            1. Initial program 69.4%

                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                            2. Add Preprocessing
                            3. Taylor expanded in lambda1 around 0 69.3%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(-\lambda_2\right)\right)}\right) \cdot R \]
                            4. Step-by-step derivation
                              1. cos-neg69.3%

                                \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \color{blue}{\cos \lambda_2}\right)\right) \cdot R \]
                              2. *-commutative69.3%

                                \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_2\right)}\right) \cdot R \]
                            5. Simplified69.3%

                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \phi_1 \cdot \left(\cos \lambda_2 \cdot \cos \phi_2\right)}\right) \cdot R \]
                          3. Recombined 3 regimes into one program.
                          4. Final simplification72.7%

                            \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq -4.1 \cdot 10^{+54}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.28 \cdot 10^{-18}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \lambda_2\right)\right)\\ \end{array} \]
                          5. Add Preprocessing

                          Alternative 10: 67.7% accurate, 1.0× speedup?

                          \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \end{array} \]
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          (FPCore (R lambda1 lambda2 phi1 phi2)
                           :precision binary64
                           (if (<= phi2 1e-13)
                             (*
                              R
                              (acos
                               (*
                                (cos phi1)
                                (+ (* (cos lambda1) (cos lambda2)) (* (sin lambda1) (sin lambda2))))))
                             (* R (acos (* (cos phi2) (cos (- lambda2 lambda1)))))))
                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                          double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                          	double tmp;
                          	if (phi2 <= 1e-13) {
                          		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                          	} else {
                          		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                          	}
                          	return tmp;
                          }
                          
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          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 <= 1d-13) then
                                  tmp = r * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))))
                              else
                                  tmp = r * acos((cos(phi2) * cos((lambda2 - lambda1))))
                              end if
                              code = tmp
                          end function
                          
                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                          public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                          	double tmp;
                          	if (phi2 <= 1e-13) {
                          		tmp = R * Math.acos((Math.cos(phi1) * ((Math.cos(lambda1) * Math.cos(lambda2)) + (Math.sin(lambda1) * Math.sin(lambda2)))));
                          	} else {
                          		tmp = R * Math.acos((Math.cos(phi2) * Math.cos((lambda2 - lambda1))));
                          	}
                          	return tmp;
                          }
                          
                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                          def code(R, lambda1, lambda2, phi1, phi2):
                          	tmp = 0
                          	if phi2 <= 1e-13:
                          		tmp = R * math.acos((math.cos(phi1) * ((math.cos(lambda1) * math.cos(lambda2)) + (math.sin(lambda1) * math.sin(lambda2)))))
                          	else:
                          		tmp = R * math.acos((math.cos(phi2) * math.cos((lambda2 - lambda1))))
                          	return tmp
                          
                          R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                          R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                          function code(R, lambda1, lambda2, phi1, phi2)
                          	tmp = 0.0
                          	if (phi2 <= 1e-13)
                          		tmp = Float64(R * acos(Float64(cos(phi1) * Float64(Float64(cos(lambda1) * cos(lambda2)) + Float64(sin(lambda1) * sin(lambda2))))));
                          	else
                          		tmp = Float64(R * acos(Float64(cos(phi2) * cos(Float64(lambda2 - lambda1)))));
                          	end
                          	return tmp
                          end
                          
                          R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                          R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                          function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                          	tmp = 0.0;
                          	if (phi2 <= 1e-13)
                          		tmp = R * acos((cos(phi1) * ((cos(lambda1) * cos(lambda2)) + (sin(lambda1) * sin(lambda2)))));
                          	else
                          		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                          	end
                          	tmp_2 = tmp;
                          end
                          
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                          code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi2, 1e-13], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[(N[(N[Cos[lambda1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[lambda1], $MachinePrecision] * N[Sin[lambda2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                          
                          \begin{array}{l}
                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                          \\
                          \begin{array}{l}
                          \mathbf{if}\;\phi_2 \leq 10^{-13}:\\
                          \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\
                          
                          
                          \end{array}
                          \end{array}
                          
                          Derivation
                          1. Split input into 2 regimes
                          2. if phi2 < 1e-13

                            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. Taylor expanded in phi2 around 0 50.9%

                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                              4. Step-by-step derivation
                                1. cos-diff61.6%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_2 \cdot \cos \lambda_1 + \sin \lambda_2 \cdot \sin \lambda_1\right)}\right) \]
                                2. +-commutative61.6%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \color{blue}{\left(\sin \lambda_2 \cdot \sin \lambda_1 + \cos \lambda_2 \cdot \cos \lambda_1\right)}\right) \]
                                3. *-commutative61.6%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\color{blue}{\sin \lambda_1 \cdot \sin \lambda_2} + \cos \lambda_2 \cdot \cos \lambda_1\right)\right) \]
                                4. *-commutative61.6%

                                  \[\leadsto R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\sin \lambda_1 \cdot \sin \lambda_2 + \color{blue}{\cos \lambda_1 \cdot \cos \lambda_2}\right)\right) \]
                              5. Applied egg-rr61.6%

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

                              if 1e-13 < phi2

                              1. Initial program 80.1%

                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                              2. Step-by-step derivation
                                1. Simplified80.1%

                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                2. Add Preprocessing
                                3. Taylor expanded in phi1 around 0 48.5%

                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                              3. Recombined 2 regimes into one program.
                              4. Final simplification58.3%

                                \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq 10^{-13}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \left(\cos \lambda_1 \cdot \cos \lambda_2 + \sin \lambda_1 \cdot \sin \lambda_2\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \]
                              5. Add Preprocessing

                              Alternative 11: 53.2% accurate, 1.0× speedup?

                              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\cos \left(\lambda_1 - \lambda_2\right) \leq 0.99998:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\ \end{array} \end{array} \]
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              (FPCore (R lambda1 lambda2 phi1 phi2)
                               :precision binary64
                               (if (<= (cos (- lambda1 lambda2)) 0.99998)
                                 (* R (acos (* (cos phi2) (cos (- lambda2 lambda1)))))
                                 (* R (acos (+ (* (sin phi1) (sin phi2)) (* (cos phi1) (cos phi2)))))))
                              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                              	double tmp;
                              	if (cos((lambda1 - lambda2)) <= 0.99998) {
                              		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                              	} else {
                              		tmp = R * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))));
                              	}
                              	return tmp;
                              }
                              
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              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 (cos((lambda1 - lambda2)) <= 0.99998d0) then
                                      tmp = r * acos((cos(phi2) * cos((lambda2 - lambda1))))
                                  else
                                      tmp = r * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))))
                                  end if
                                  code = tmp
                              end function
                              
                              assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                              assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                              public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                              	double tmp;
                              	if (Math.cos((lambda1 - lambda2)) <= 0.99998) {
                              		tmp = R * Math.acos((Math.cos(phi2) * Math.cos((lambda2 - lambda1))));
                              	} else {
                              		tmp = R * Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + (Math.cos(phi1) * Math.cos(phi2))));
                              	}
                              	return tmp;
                              }
                              
                              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                              def code(R, lambda1, lambda2, phi1, phi2):
                              	tmp = 0
                              	if math.cos((lambda1 - lambda2)) <= 0.99998:
                              		tmp = R * math.acos((math.cos(phi2) * math.cos((lambda2 - lambda1))))
                              	else:
                              		tmp = R * math.acos(((math.sin(phi1) * math.sin(phi2)) + (math.cos(phi1) * math.cos(phi2))))
                              	return tmp
                              
                              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                              function code(R, lambda1, lambda2, phi1, phi2)
                              	tmp = 0.0
                              	if (cos(Float64(lambda1 - lambda2)) <= 0.99998)
                              		tmp = Float64(R * acos(Float64(cos(phi2) * cos(Float64(lambda2 - lambda1)))));
                              	else
                              		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(cos(phi1) * cos(phi2)))));
                              	end
                              	return tmp
                              end
                              
                              R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                              R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                              function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                              	tmp = 0.0;
                              	if (cos((lambda1 - lambda2)) <= 0.99998)
                              		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                              	else
                              		tmp = R * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))));
                              	end
                              	tmp_2 = tmp;
                              end
                              
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                              code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision], 0.99998], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                              
                              \begin{array}{l}
                              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                              \\
                              \begin{array}{l}
                              \mathbf{if}\;\cos \left(\lambda_1 - \lambda_2\right) \leq 0.99998:\\
                              \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\
                              
                              \mathbf{else}:\\
                              \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\
                              
                              
                              \end{array}
                              \end{array}
                              
                              Derivation
                              1. Split input into 2 regimes
                              2. if (cos.f64 (-.f64 lambda1 lambda2)) < 0.99997999999999998

                                1. Initial program 77.7%

                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                2. Step-by-step derivation
                                  1. Simplified77.7%

                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                  2. Add Preprocessing
                                  3. Taylor expanded in phi1 around 0 46.3%

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

                                  if 0.99997999999999998 < (cos.f64 (-.f64 lambda1 lambda2))

                                  1. Initial program 70.0%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Simplified70.0%

                                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                                  3. Add Preprocessing
                                  4. Taylor expanded in lambda2 around 0 70.0%

                                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)}\right)\right) \cdot R \]
                                  5. Step-by-step derivation
                                    1. *-commutative70.0%

                                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                  6. Simplified70.0%

                                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                  7. Taylor expanded in lambda1 around 0 69.1%

                                    \[\leadsto \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_2 + \sin \phi_1 \cdot \sin \phi_2\right)} \cdot R \]
                                3. Recombined 2 regimes into one program.
                                4. Final simplification52.3%

                                  \[\leadsto \begin{array}{l} \mathbf{if}\;\cos \left(\lambda_1 - \lambda_2\right) \leq 0.99998:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\ \end{array} \]
                                5. Add Preprocessing

                                Alternative 12: 59.8% accurate, 1.0× speedup?

                                \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.062:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \cos \phi_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 0.095:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \end{array} \]
                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                 :precision binary64
                                 (if (<= phi2 -0.062)
                                   (* R (acos (fma (sin phi1) (sin phi2) (* (cos phi1) (cos phi2)))))
                                   (if (<= phi2 0.095)
                                     (*
                                      R
                                      (acos
                                       (+
                                        (* (sin phi1) phi2)
                                        (*
                                         (+ (* -0.5 (pow phi2 2.0)) 1.0)
                                         (* (cos phi1) (cos (- lambda1 lambda2)))))))
                                     (* R (acos (* (cos phi2) (cos (- lambda2 lambda1))))))))
                                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                	double tmp;
                                	if (phi2 <= -0.062) {
                                		tmp = R * acos(fma(sin(phi1), sin(phi2), (cos(phi1) * cos(phi2))));
                                	} else if (phi2 <= 0.095) {
                                		tmp = R * acos(((sin(phi1) * phi2) + (((-0.5 * pow(phi2, 2.0)) + 1.0) * (cos(phi1) * cos((lambda1 - lambda2))))));
                                	} else {
                                		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                                	}
                                	return tmp;
                                }
                                
                                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                function code(R, lambda1, lambda2, phi1, phi2)
                                	tmp = 0.0
                                	if (phi2 <= -0.062)
                                		tmp = Float64(R * acos(fma(sin(phi1), sin(phi2), Float64(cos(phi1) * cos(phi2)))));
                                	elseif (phi2 <= 0.095)
                                		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * phi2) + Float64(Float64(Float64(-0.5 * (phi2 ^ 2.0)) + 1.0) * Float64(cos(phi1) * cos(Float64(lambda1 - lambda2)))))));
                                	else
                                		tmp = Float64(R * acos(Float64(cos(phi2) * cos(Float64(lambda2 - lambda1)))));
                                	end
                                	return tmp
                                end
                                
                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi2, -0.062], N[(R * N[ArcCos[N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 0.095], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * phi2), $MachinePrecision] + N[(N[(N[(-0.5 * N[Power[phi2, 2.0], $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] * N[(N[Cos[phi1], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
                                
                                \begin{array}{l}
                                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                \\
                                \begin{array}{l}
                                \mathbf{if}\;\phi_2 \leq -0.062:\\
                                \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \cos \phi_2\right)\right)\\
                                
                                \mathbf{elif}\;\phi_2 \leq 0.095:\\
                                \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 3 regimes
                                2. if phi2 < -0.062

                                  1. Initial program 85.6%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Simplified85.7%

                                    \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                                  3. Add Preprocessing
                                  4. Taylor expanded in lambda2 around 0 62.8%

                                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)}\right)\right) \cdot R \]
                                  5. Step-by-step derivation
                                    1. *-commutative62.8%

                                      \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                  6. Simplified62.8%

                                    \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                  7. Taylor expanded in lambda1 around 0 38.8%

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

                                  if -0.062 < phi2 < 0.095000000000000001

                                  1. Initial program 68.3%

                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                  2. Step-by-step derivation
                                    1. Simplified68.3%

                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                    2. Add Preprocessing
                                    3. Taylor expanded in phi2 around 0 67.3%

                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \left(\sin \phi_1 + -0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                    4. Step-by-step derivation
                                      1. distribute-rgt-in67.3%

                                        \[\leadsto R \cdot \cos^{-1} \left(\color{blue}{\left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2\right)} + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                      2. *-commutative67.3%

                                        \[\leadsto R \cdot \cos^{-1} \left(\left(\color{blue}{\phi_2 \cdot \sin \phi_1} + \left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2\right) + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                      3. associate-+l+67.3%

                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \sin \phi_1 + \left(\left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2 + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)} \]
                                    5. Simplified67.3%

                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \sin \phi_1 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]

                                    if 0.095000000000000001 < phi2

                                    1. Initial program 80.5%

                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                    2. Step-by-step derivation
                                      1. Simplified80.5%

                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                      2. Add Preprocessing
                                      3. Taylor expanded in phi1 around 0 48.5%

                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                    3. Recombined 3 regimes into one program.
                                    4. Final simplification55.6%

                                      \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.062:\\ \;\;\;\;R \cdot \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \cos \phi_2\right)\right)\\ \mathbf{elif}\;\phi_2 \leq 0.095:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \]
                                    5. Add Preprocessing

                                    Alternative 13: 59.8% accurate, 1.2× speedup?

                                    \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.056:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\ \mathbf{elif}\;\phi_2 \leq 0.095:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \end{array} \]
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                     :precision binary64
                                     (if (<= phi2 -0.056)
                                       (* R (acos (+ (* (sin phi1) (sin phi2)) (* (cos phi1) (cos phi2)))))
                                       (if (<= phi2 0.095)
                                         (*
                                          R
                                          (acos
                                           (+
                                            (* (sin phi1) phi2)
                                            (*
                                             (+ (* -0.5 (pow phi2 2.0)) 1.0)
                                             (* (cos phi1) (cos (- lambda1 lambda2)))))))
                                         (* R (acos (* (cos phi2) (cos (- lambda2 lambda1))))))))
                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                    	double tmp;
                                    	if (phi2 <= -0.056) {
                                    		tmp = R * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))));
                                    	} else if (phi2 <= 0.095) {
                                    		tmp = R * acos(((sin(phi1) * phi2) + (((-0.5 * pow(phi2, 2.0)) + 1.0) * (cos(phi1) * cos((lambda1 - lambda2))))));
                                    	} else {
                                    		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    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 <= (-0.056d0)) then
                                            tmp = r * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))))
                                        else if (phi2 <= 0.095d0) then
                                            tmp = r * acos(((sin(phi1) * phi2) + ((((-0.5d0) * (phi2 ** 2.0d0)) + 1.0d0) * (cos(phi1) * cos((lambda1 - lambda2))))))
                                        else
                                            tmp = r * acos((cos(phi2) * cos((lambda2 - lambda1))))
                                        end if
                                        code = tmp
                                    end function
                                    
                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                    	double tmp;
                                    	if (phi2 <= -0.056) {
                                    		tmp = R * Math.acos(((Math.sin(phi1) * Math.sin(phi2)) + (Math.cos(phi1) * Math.cos(phi2))));
                                    	} else if (phi2 <= 0.095) {
                                    		tmp = R * Math.acos(((Math.sin(phi1) * phi2) + (((-0.5 * Math.pow(phi2, 2.0)) + 1.0) * (Math.cos(phi1) * Math.cos((lambda1 - lambda2))))));
                                    	} else {
                                    		tmp = R * Math.acos((Math.cos(phi2) * Math.cos((lambda2 - lambda1))));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                    def code(R, lambda1, lambda2, phi1, phi2):
                                    	tmp = 0
                                    	if phi2 <= -0.056:
                                    		tmp = R * math.acos(((math.sin(phi1) * math.sin(phi2)) + (math.cos(phi1) * math.cos(phi2))))
                                    	elif phi2 <= 0.095:
                                    		tmp = R * math.acos(((math.sin(phi1) * phi2) + (((-0.5 * math.pow(phi2, 2.0)) + 1.0) * (math.cos(phi1) * math.cos((lambda1 - lambda2))))))
                                    	else:
                                    		tmp = R * math.acos((math.cos(phi2) * math.cos((lambda2 - lambda1))))
                                    	return tmp
                                    
                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                    function code(R, lambda1, lambda2, phi1, phi2)
                                    	tmp = 0.0
                                    	if (phi2 <= -0.056)
                                    		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * sin(phi2)) + Float64(cos(phi1) * cos(phi2)))));
                                    	elseif (phi2 <= 0.095)
                                    		tmp = Float64(R * acos(Float64(Float64(sin(phi1) * phi2) + Float64(Float64(Float64(-0.5 * (phi2 ^ 2.0)) + 1.0) * Float64(cos(phi1) * cos(Float64(lambda1 - lambda2)))))));
                                    	else
                                    		tmp = Float64(R * acos(Float64(cos(phi2) * cos(Float64(lambda2 - lambda1)))));
                                    	end
                                    	return tmp
                                    end
                                    
                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                    function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                    	tmp = 0.0;
                                    	if (phi2 <= -0.056)
                                    		tmp = R * acos(((sin(phi1) * sin(phi2)) + (cos(phi1) * cos(phi2))));
                                    	elseif (phi2 <= 0.095)
                                    		tmp = R * acos(((sin(phi1) * phi2) + (((-0.5 * (phi2 ^ 2.0)) + 1.0) * (cos(phi1) * cos((lambda1 - lambda2))))));
                                    	else
                                    		tmp = R * acos((cos(phi2) * cos((lambda2 - lambda1))));
                                    	end
                                    	tmp_2 = tmp;
                                    end
                                    
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi2, -0.056], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[phi2], $MachinePrecision]), $MachinePrecision] + N[(N[Cos[phi1], $MachinePrecision] * N[Cos[phi2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi2, 0.095], N[(R * N[ArcCos[N[(N[(N[Sin[phi1], $MachinePrecision] * phi2), $MachinePrecision] + N[(N[(N[(-0.5 * N[Power[phi2, 2.0], $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] * N[(N[Cos[phi1], $MachinePrecision] * N[Cos[N[(lambda1 - lambda2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
                                    
                                    \begin{array}{l}
                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                    \\
                                    \begin{array}{l}
                                    \mathbf{if}\;\phi_2 \leq -0.056:\\
                                    \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\
                                    
                                    \mathbf{elif}\;\phi_2 \leq 0.095:\\
                                    \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\
                                    
                                    \mathbf{else}:\\
                                    \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\
                                    
                                    
                                    \end{array}
                                    \end{array}
                                    
                                    Derivation
                                    1. Split input into 3 regimes
                                    2. if phi2 < -0.0560000000000000012

                                      1. Initial program 85.6%

                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                      2. Simplified85.7%

                                        \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                                      3. Add Preprocessing
                                      4. Taylor expanded in lambda2 around 0 62.8%

                                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)}\right)\right) \cdot R \]
                                      5. Step-by-step derivation
                                        1. *-commutative62.8%

                                          \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                      6. Simplified62.8%

                                        \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                      7. Taylor expanded in lambda1 around 0 38.7%

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

                                      if -0.0560000000000000012 < phi2 < 0.095000000000000001

                                      1. Initial program 68.3%

                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                      2. Step-by-step derivation
                                        1. Simplified68.3%

                                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                        2. Add Preprocessing
                                        3. Taylor expanded in phi2 around 0 67.3%

                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \left(\sin \phi_1 + -0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                        4. Step-by-step derivation
                                          1. distribute-rgt-in67.3%

                                            \[\leadsto R \cdot \cos^{-1} \left(\color{blue}{\left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2\right)} + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                          2. *-commutative67.3%

                                            \[\leadsto R \cdot \cos^{-1} \left(\left(\color{blue}{\phi_2 \cdot \sin \phi_1} + \left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2\right) + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right) \]
                                          3. associate-+l+67.3%

                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \sin \phi_1 + \left(\left(-0.5 \cdot \left(\phi_2 \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)\right) \cdot \phi_2 + \cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\right)} \]
                                        5. Simplified67.3%

                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\phi_2 \cdot \sin \phi_1 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)} \]

                                        if 0.095000000000000001 < phi2

                                        1. Initial program 80.5%

                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                        2. Step-by-step derivation
                                          1. Simplified80.5%

                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                          2. Add Preprocessing
                                          3. Taylor expanded in phi1 around 0 48.5%

                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                        3. Recombined 3 regimes into one program.
                                        4. Final simplification55.6%

                                          \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq -0.056:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \cos \phi_1 \cdot \cos \phi_2\right)\\ \mathbf{elif}\;\phi_2 \leq 0.095:\\ \;\;\;\;R \cdot \cos^{-1} \left(\sin \phi_1 \cdot \phi_2 + \left(-0.5 \cdot {\phi_2}^{2} + 1\right) \cdot \left(\cos \phi_1 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \end{array} \]
                                        5. Add Preprocessing

                                        Alternative 14: 42.0% accurate, 1.9× speedup?

                                        \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.32 \cdot 10^{+91}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\phi_1 \leq -1.38 \cdot 10^{+20}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \lambda_1\right)\\ \end{array} \end{array} \]
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        (FPCore (R lambda1 lambda2 phi1 phi2)
                                         :precision binary64
                                         (if (<= phi1 -1.32e+91)
                                           (* R (acos (* (cos phi1) (cos lambda1))))
                                           (if (<= phi1 -1.38e+20)
                                             (* R (acos (* (cos phi1) (cos lambda2))))
                                             (* R (acos (* (cos phi2) (cos lambda1)))))))
                                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                        	double tmp;
                                        	if (phi1 <= -1.32e+91) {
                                        		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                        	} else if (phi1 <= -1.38e+20) {
                                        		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                        	} else {
                                        		tmp = R * acos((cos(phi2) * cos(lambda1)));
                                        	}
                                        	return tmp;
                                        }
                                        
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        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 (phi1 <= (-1.32d+91)) then
                                                tmp = r * acos((cos(phi1) * cos(lambda1)))
                                            else if (phi1 <= (-1.38d+20)) then
                                                tmp = r * acos((cos(phi1) * cos(lambda2)))
                                            else
                                                tmp = r * acos((cos(phi2) * cos(lambda1)))
                                            end if
                                            code = tmp
                                        end function
                                        
                                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                        public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                        	double tmp;
                                        	if (phi1 <= -1.32e+91) {
                                        		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda1)));
                                        	} else if (phi1 <= -1.38e+20) {
                                        		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda2)));
                                        	} else {
                                        		tmp = R * Math.acos((Math.cos(phi2) * Math.cos(lambda1)));
                                        	}
                                        	return tmp;
                                        }
                                        
                                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                        def code(R, lambda1, lambda2, phi1, phi2):
                                        	tmp = 0
                                        	if phi1 <= -1.32e+91:
                                        		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda1)))
                                        	elif phi1 <= -1.38e+20:
                                        		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda2)))
                                        	else:
                                        		tmp = R * math.acos((math.cos(phi2) * math.cos(lambda1)))
                                        	return tmp
                                        
                                        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                        R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                        function code(R, lambda1, lambda2, phi1, phi2)
                                        	tmp = 0.0
                                        	if (phi1 <= -1.32e+91)
                                        		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda1))));
                                        	elseif (phi1 <= -1.38e+20)
                                        		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda2))));
                                        	else
                                        		tmp = Float64(R * acos(Float64(cos(phi2) * cos(lambda1))));
                                        	end
                                        	return tmp
                                        end
                                        
                                        R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                        R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                        function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                        	tmp = 0.0;
                                        	if (phi1 <= -1.32e+91)
                                        		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                        	elseif (phi1 <= -1.38e+20)
                                        		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                        	else
                                        		tmp = R * acos((cos(phi2) * cos(lambda1)));
                                        	end
                                        	tmp_2 = tmp;
                                        end
                                        
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi1, -1.32e+91], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[phi1, -1.38e+20], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
                                        
                                        \begin{array}{l}
                                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                        \\
                                        \begin{array}{l}
                                        \mathbf{if}\;\phi_1 \leq -1.32 \cdot 10^{+91}:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\
                                        
                                        \mathbf{elif}\;\phi_1 \leq -1.38 \cdot 10^{+20}:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\
                                        
                                        \mathbf{else}:\\
                                        \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \lambda_1\right)\\
                                        
                                        
                                        \end{array}
                                        \end{array}
                                        
                                        Derivation
                                        1. Split input into 3 regimes
                                        2. if phi1 < -1.32000000000000003e91

                                          1. Initial program 81.0%

                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                          2. Simplified81.0%

                                            \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                                          3. Add Preprocessing
                                          4. Taylor expanded in lambda2 around 0 67.1%

                                            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)}\right)\right) \cdot R \]
                                          5. Step-by-step derivation
                                            1. *-commutative67.1%

                                              \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                          6. Simplified67.1%

                                            \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                          7. Taylor expanded in phi2 around 0 40.3%

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

                                          if -1.32000000000000003e91 < phi1 < -1.38e20

                                          1. Initial program 93.5%

                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                          2. Step-by-step derivation
                                            1. Simplified93.5%

                                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                            2. Add Preprocessing
                                            3. Taylor expanded in phi2 around 0 41.1%

                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                            4. Taylor expanded in lambda1 around 0 26.4%

                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_1\right)} \]
                                            5. Step-by-step derivation
                                              1. *-commutative26.4%

                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_2\right)} \]
                                            6. Simplified26.4%

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

                                            if -1.38e20 < phi1

                                            1. Initial program 73.5%

                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                            2. Add Preprocessing
                                            3. Taylor expanded in lambda2 around 0 51.1%

                                              \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \lambda_1 \cdot \left(\cos \phi_1 \cdot \cos \phi_2\right)}\right) \cdot R \]
                                            4. Taylor expanded in phi1 around 0 30.9%

                                              \[\leadsto \cos^{-1} \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)} \cdot R \]
                                          3. Recombined 3 regimes into one program.
                                          4. Final simplification32.3%

                                            \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.32 \cdot 10^{+91}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\phi_1 \leq -1.38 \cdot 10^{+20}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \lambda_1\right)\\ \end{array} \]
                                          5. Add Preprocessing

                                          Alternative 15: 41.5% accurate, 1.9× speedup?

                                          \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 8.8 \cdot 10^{-76}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.02 \cdot 10^{-44}:\\ \;\;\;\;R \cdot \left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \end{array} \end{array} \]
                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                          (FPCore (R lambda1 lambda2 phi1 phi2)
                                           :precision binary64
                                           (if (<= lambda2 8.8e-76)
                                             (* R (acos (* (cos phi1) (cos lambda1))))
                                             (if (<= lambda2 1.02e-44)
                                               (* R (fabs (remainder (- lambda2 lambda1) (* 2.0 PI))))
                                               (* R (acos (* (cos phi1) (cos lambda2)))))))
                                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                          double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                          	double tmp;
                                          	if (lambda2 <= 8.8e-76) {
                                          		tmp = R * acos((cos(phi1) * cos(lambda1)));
                                          	} else if (lambda2 <= 1.02e-44) {
                                          		tmp = R * fabs(remainder((lambda2 - lambda1), (2.0 * ((double) M_PI))));
                                          	} else {
                                          		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                          	}
                                          	return tmp;
                                          }
                                          
                                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                          public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                          	double tmp;
                                          	if (lambda2 <= 8.8e-76) {
                                          		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda1)));
                                          	} else if (lambda2 <= 1.02e-44) {
                                          		tmp = R * Math.abs(Math.IEEEremainder((lambda2 - lambda1), (2.0 * Math.PI)));
                                          	} else {
                                          		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda2)));
                                          	}
                                          	return tmp;
                                          }
                                          
                                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                          def code(R, lambda1, lambda2, phi1, phi2):
                                          	tmp = 0
                                          	if lambda2 <= 8.8e-76:
                                          		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda1)))
                                          	elif lambda2 <= 1.02e-44:
                                          		tmp = R * math.fabs(math.remainder((lambda2 - lambda1), (2.0 * math.pi)))
                                          	else:
                                          		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda2)))
                                          	return tmp
                                          
                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                          code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda2, 8.8e-76], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[lambda2, 1.02e-44], N[(R * N[Abs[N[With[{TMP1 = N[(lambda2 - lambda1), $MachinePrecision], TMP2 = N[(2.0 * Pi), $MachinePrecision]}, TMP1 - Round[TMP1 / TMP2] * TMP2], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
                                          
                                          \begin{array}{l}
                                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                          \\
                                          \begin{array}{l}
                                          \mathbf{if}\;\lambda_2 \leq 8.8 \cdot 10^{-76}:\\
                                          \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\
                                          
                                          \mathbf{elif}\;\lambda_2 \leq 1.02 \cdot 10^{-44}:\\
                                          \;\;\;\;R \cdot \left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\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 3 regimes
                                          2. if lambda2 < 8.79999999999999997e-76

                                            1. Initial program 77.6%

                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                            2. Simplified77.7%

                                              \[\leadsto \color{blue}{\cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \left(\cos \phi_2 \cdot \cos \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \cdot R} \]
                                            3. Add Preprocessing
                                            4. Taylor expanded in lambda2 around 0 63.5%

                                              \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)}\right)\right) \cdot R \]
                                            5. Step-by-step derivation
                                              1. *-commutative63.5%

                                                \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                            6. Simplified63.5%

                                              \[\leadsto \cos^{-1} \left(\mathsf{fma}\left(\sin \phi_1, \sin \phi_2, \cos \phi_1 \cdot \color{blue}{\left(\cos \phi_2 \cdot \cos \lambda_1\right)}\right)\right) \cdot R \]
                                            7. Taylor expanded in phi2 around 0 39.1%

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

                                            if 8.79999999999999997e-76 < lambda2 < 1.0199999999999999e-44

                                            1. Initial program 56.8%

                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                            2. Step-by-step derivation
                                              1. Simplified56.8%

                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                              2. Add Preprocessing
                                              3. Taylor expanded in phi2 around 0 30.3%

                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                              4. Taylor expanded in phi1 around 0 9.3%

                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                              5. Step-by-step derivation
                                                1. acos-cos52.1%

                                                  \[\leadsto R \cdot \color{blue}{\left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|} \]
                                              6. Applied egg-rr52.1%

                                                \[\leadsto R \cdot \color{blue}{\left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|} \]

                                              if 1.0199999999999999e-44 < lambda2

                                              1. Initial program 72.3%

                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                              2. Step-by-step derivation
                                                1. Simplified72.3%

                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                2. Add Preprocessing
                                                3. Taylor expanded in phi2 around 0 35.4%

                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                4. Taylor expanded in lambda1 around 0 31.6%

                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_1\right)} \]
                                                5. Step-by-step derivation
                                                  1. *-commutative31.6%

                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_2\right)} \]
                                                6. Simplified31.6%

                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \lambda_2\right)} \]
                                              3. Recombined 3 regimes into one program.
                                              4. Final simplification37.8%

                                                \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_2 \leq 8.8 \cdot 10^{-76}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_1\right)\\ \mathbf{elif}\;\lambda_2 \leq 1.02 \cdot 10^{-44}:\\ \;\;\;\;R \cdot \left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \end{array} \]
                                              5. Add Preprocessing

                                              Alternative 16: 57.1% accurate, 2.0× speedup?

                                              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} t_0 := \cos \left(\lambda_2 - \lambda_1\right)\\ \mathbf{if}\;\phi_2 \leq 4.5 \cdot 10^{-56}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot t\_0\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot t\_0\right)\\ \end{array} \end{array} \]
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              (FPCore (R lambda1 lambda2 phi1 phi2)
                                               :precision binary64
                                               (let* ((t_0 (cos (- lambda2 lambda1))))
                                                 (if (<= phi2 4.5e-56)
                                                   (* R (acos (* (cos phi1) t_0)))
                                                   (* R (acos (* (cos phi2) t_0))))))
                                              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                              	double t_0 = cos((lambda2 - lambda1));
                                              	double tmp;
                                              	if (phi2 <= 4.5e-56) {
                                              		tmp = R * acos((cos(phi1) * t_0));
                                              	} else {
                                              		tmp = R * acos((cos(phi2) * t_0));
                                              	}
                                              	return tmp;
                                              }
                                              
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              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 <= 4.5d-56) then
                                                      tmp = r * acos((cos(phi1) * t_0))
                                                  else
                                                      tmp = r * acos((cos(phi2) * t_0))
                                                  end if
                                                  code = tmp
                                              end function
                                              
                                              assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                              assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                              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 <= 4.5e-56) {
                                              		tmp = R * Math.acos((Math.cos(phi1) * t_0));
                                              	} else {
                                              		tmp = R * Math.acos((Math.cos(phi2) * t_0));
                                              	}
                                              	return tmp;
                                              }
                                              
                                              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                              def code(R, lambda1, lambda2, phi1, phi2):
                                              	t_0 = math.cos((lambda2 - lambda1))
                                              	tmp = 0
                                              	if phi2 <= 4.5e-56:
                                              		tmp = R * math.acos((math.cos(phi1) * t_0))
                                              	else:
                                              		tmp = R * math.acos((math.cos(phi2) * t_0))
                                              	return tmp
                                              
                                              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                              function code(R, lambda1, lambda2, phi1, phi2)
                                              	t_0 = cos(Float64(lambda2 - lambda1))
                                              	tmp = 0.0
                                              	if (phi2 <= 4.5e-56)
                                              		tmp = Float64(R * acos(Float64(cos(phi1) * t_0)));
                                              	else
                                              		tmp = Float64(R * acos(Float64(cos(phi2) * t_0)));
                                              	end
                                              	return tmp
                                              end
                                              
                                              R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                              R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                              function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                              	t_0 = cos((lambda2 - lambda1));
                                              	tmp = 0.0;
                                              	if (phi2 <= 4.5e-56)
                                              		tmp = R * acos((cos(phi1) * t_0));
                                              	else
                                              		tmp = R * acos((cos(phi2) * t_0));
                                              	end
                                              	tmp_2 = tmp;
                                              end
                                              
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                              code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[phi2, 4.5e-56], 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}
                                              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                              \\
                                              \begin{array}{l}
                                              t_0 := \cos \left(\lambda_2 - \lambda_1\right)\\
                                              \mathbf{if}\;\phi_2 \leq 4.5 \cdot 10^{-56}:\\
                                              \;\;\;\;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 < 4.5000000000000001e-56

                                                1. Initial program 75.4%

                                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                2. Step-by-step derivation
                                                  1. Simplified75.4%

                                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                  2. Add Preprocessing
                                                  3. Taylor expanded in phi2 around 0 50.8%

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

                                                  if 4.5000000000000001e-56 < phi2

                                                  1. Initial program 76.1%

                                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                  2. Step-by-step derivation
                                                    1. Simplified76.1%

                                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                    2. Add Preprocessing
                                                    3. Taylor expanded in phi1 around 0 43.5%

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

                                                  Alternative 17: 53.0% accurate, 2.0× speedup?

                                                  \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq 1.6 \cdot 10^{-9}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \lambda_1\right)\\ \end{array} \end{array} \]
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  (FPCore (R lambda1 lambda2 phi1 phi2)
                                                   :precision binary64
                                                   (if (<= phi2 1.6e-9)
                                                     (* R (acos (* (cos phi1) (cos (- lambda2 lambda1)))))
                                                     (* R (acos (* (cos phi2) (cos lambda1))))))
                                                  assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                  assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                  double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                  	double tmp;
                                                  	if (phi2 <= 1.6e-9) {
                                                  		tmp = R * acos((cos(phi1) * cos((lambda2 - lambda1))));
                                                  	} else {
                                                  		tmp = R * acos((cos(phi2) * cos(lambda1)));
                                                  	}
                                                  	return tmp;
                                                  }
                                                  
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  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 <= 1.6d-9) then
                                                          tmp = r * acos((cos(phi1) * cos((lambda2 - lambda1))))
                                                      else
                                                          tmp = r * acos((cos(phi2) * cos(lambda1)))
                                                      end if
                                                      code = tmp
                                                  end function
                                                  
                                                  assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                  assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                  public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                  	double tmp;
                                                  	if (phi2 <= 1.6e-9) {
                                                  		tmp = R * Math.acos((Math.cos(phi1) * Math.cos((lambda2 - lambda1))));
                                                  	} else {
                                                  		tmp = R * Math.acos((Math.cos(phi2) * Math.cos(lambda1)));
                                                  	}
                                                  	return tmp;
                                                  }
                                                  
                                                  [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                  [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                  def code(R, lambda1, lambda2, phi1, phi2):
                                                  	tmp = 0
                                                  	if phi2 <= 1.6e-9:
                                                  		tmp = R * math.acos((math.cos(phi1) * math.cos((lambda2 - lambda1))))
                                                  	else:
                                                  		tmp = R * math.acos((math.cos(phi2) * math.cos(lambda1)))
                                                  	return tmp
                                                  
                                                  R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                  R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                  function code(R, lambda1, lambda2, phi1, phi2)
                                                  	tmp = 0.0
                                                  	if (phi2 <= 1.6e-9)
                                                  		tmp = Float64(R * acos(Float64(cos(phi1) * cos(Float64(lambda2 - lambda1)))));
                                                  	else
                                                  		tmp = Float64(R * acos(Float64(cos(phi2) * cos(lambda1))));
                                                  	end
                                                  	return tmp
                                                  end
                                                  
                                                  R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                  R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                  function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                  	tmp = 0.0;
                                                  	if (phi2 <= 1.6e-9)
                                                  		tmp = R * acos((cos(phi1) * cos((lambda2 - lambda1))));
                                                  	else
                                                  		tmp = R * acos((cos(phi2) * cos(lambda1)));
                                                  	end
                                                  	tmp_2 = tmp;
                                                  end
                                                  
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                  code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[phi2, 1.6e-9], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi2], $MachinePrecision] * N[Cos[lambda1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                  
                                                  \begin{array}{l}
                                                  [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                  [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                  \\
                                                  \begin{array}{l}
                                                  \mathbf{if}\;\phi_2 \leq 1.6 \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 \lambda_1\right)\\
                                                  
                                                  
                                                  \end{array}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Split input into 2 regimes
                                                  2. if phi2 < 1.60000000000000006e-9

                                                    1. Initial program 74.2%

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

                                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                      2. Add Preprocessing
                                                      3. Taylor expanded in phi2 around 0 51.1%

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

                                                      if 1.60000000000000006e-9 < phi2

                                                      1. Initial program 79.8%

                                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                      2. Add Preprocessing
                                                      3. Taylor expanded in lambda2 around 0 51.6%

                                                        \[\leadsto \cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \color{blue}{\cos \lambda_1 \cdot \left(\cos \phi_1 \cdot \cos \phi_2\right)}\right) \cdot R \]
                                                      4. Taylor expanded in phi1 around 0 29.1%

                                                        \[\leadsto \cos^{-1} \color{blue}{\left(\cos \lambda_1 \cdot \cos \phi_2\right)} \cdot R \]
                                                    3. Recombined 2 regimes into one program.
                                                    4. Final simplification45.7%

                                                      \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_2 \leq 1.6 \cdot 10^{-9}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_2 \cdot \cos \lambda_1\right)\\ \end{array} \]
                                                    5. Add Preprocessing

                                                    Alternative 18: 36.5% accurate, 2.0× speedup?

                                                    \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -1.02 \cdot 10^{+68}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \left(\cos \phi_1 \cdot \cos \lambda_2\right)\\ \end{array} \end{array} \]
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                                     :precision binary64
                                                     (if (<= lambda1 -1.02e+68)
                                                       (* R (acos (cos lambda1)))
                                                       (* R (acos (* (cos phi1) (cos lambda2))))))
                                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                    	double tmp;
                                                    	if (lambda1 <= -1.02e+68) {
                                                    		tmp = R * acos(cos(lambda1));
                                                    	} else {
                                                    		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                                    	}
                                                    	return tmp;
                                                    }
                                                    
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    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 <= (-1.02d+68)) then
                                                            tmp = r * acos(cos(lambda1))
                                                        else
                                                            tmp = r * acos((cos(phi1) * cos(lambda2)))
                                                        end if
                                                        code = tmp
                                                    end function
                                                    
                                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                    	double tmp;
                                                    	if (lambda1 <= -1.02e+68) {
                                                    		tmp = R * Math.acos(Math.cos(lambda1));
                                                    	} else {
                                                    		tmp = R * Math.acos((Math.cos(phi1) * Math.cos(lambda2)));
                                                    	}
                                                    	return tmp;
                                                    }
                                                    
                                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                    def code(R, lambda1, lambda2, phi1, phi2):
                                                    	tmp = 0
                                                    	if lambda1 <= -1.02e+68:
                                                    		tmp = R * math.acos(math.cos(lambda1))
                                                    	else:
                                                    		tmp = R * math.acos((math.cos(phi1) * math.cos(lambda2)))
                                                    	return tmp
                                                    
                                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                    function code(R, lambda1, lambda2, phi1, phi2)
                                                    	tmp = 0.0
                                                    	if (lambda1 <= -1.02e+68)
                                                    		tmp = Float64(R * acos(cos(lambda1)));
                                                    	else
                                                    		tmp = Float64(R * acos(Float64(cos(phi1) * cos(lambda2))));
                                                    	end
                                                    	return tmp
                                                    end
                                                    
                                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                    function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                    	tmp = 0.0;
                                                    	if (lambda1 <= -1.02e+68)
                                                    		tmp = R * acos(cos(lambda1));
                                                    	else
                                                    		tmp = R * acos((cos(phi1) * cos(lambda2)));
                                                    	end
                                                    	tmp_2 = tmp;
                                                    end
                                                    
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -1.02e+68], N[(R * N[ArcCos[N[Cos[lambda1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[(N[Cos[phi1], $MachinePrecision] * N[Cos[lambda2], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                    
                                                    \begin{array}{l}
                                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                    \\
                                                    \begin{array}{l}
                                                    \mathbf{if}\;\lambda_1 \leq -1.02 \cdot 10^{+68}:\\
                                                    \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\
                                                    
                                                    \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 lambda1 < -1.02e68

                                                      1. Initial program 65.5%

                                                        \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                      2. Step-by-step derivation
                                                        1. Simplified65.5%

                                                          \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                        2. Add Preprocessing
                                                        3. Taylor expanded in phi2 around 0 43.3%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                        4. Taylor expanded in phi1 around 0 33.8%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                        5. Taylor expanded in lambda2 around 0 33.9%

                                                          \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(-\lambda_1\right)} \]
                                                        6. Step-by-step derivation
                                                          1. cos-neg33.9%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]
                                                        7. Simplified33.9%

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

                                                        if -1.02e68 < lambda1

                                                        1. Initial program 77.9%

                                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                        2. Step-by-step derivation
                                                          1. Simplified77.9%

                                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                          2. Add Preprocessing
                                                          3. Taylor expanded in phi2 around 0 43.7%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                          4. Taylor expanded in lambda1 around 0 34.6%

                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \lambda_2 \cdot \cos \phi_1\right)} \]
                                                          5. Step-by-step derivation
                                                            1. *-commutative34.6%

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

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

                                                        Alternative 19: 23.9% accurate, 2.9× speedup?

                                                        \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -5.8 \cdot 10^{-97}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|\\ \end{array} \end{array} \]
                                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                        (FPCore (R lambda1 lambda2 phi1 phi2)
                                                         :precision binary64
                                                         (if (<= lambda1 -5.8e-97)
                                                           (* R (acos (cos (- lambda2 lambda1))))
                                                           (* R (fabs (remainder (- lambda2 lambda1) (* 2.0 PI))))))
                                                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                        assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                        double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                        	double tmp;
                                                        	if (lambda1 <= -5.8e-97) {
                                                        		tmp = R * acos(cos((lambda2 - lambda1)));
                                                        	} else {
                                                        		tmp = R * fabs(remainder((lambda2 - lambda1), (2.0 * ((double) M_PI))));
                                                        	}
                                                        	return tmp;
                                                        }
                                                        
                                                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                        assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                        public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                        	double tmp;
                                                        	if (lambda1 <= -5.8e-97) {
                                                        		tmp = R * Math.acos(Math.cos((lambda2 - lambda1)));
                                                        	} else {
                                                        		tmp = R * Math.abs(Math.IEEEremainder((lambda2 - lambda1), (2.0 * Math.PI)));
                                                        	}
                                                        	return tmp;
                                                        }
                                                        
                                                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                        [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                        def code(R, lambda1, lambda2, phi1, phi2):
                                                        	tmp = 0
                                                        	if lambda1 <= -5.8e-97:
                                                        		tmp = R * math.acos(math.cos((lambda2 - lambda1)))
                                                        	else:
                                                        		tmp = R * math.fabs(math.remainder((lambda2 - lambda1), (2.0 * math.pi)))
                                                        	return tmp
                                                        
                                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                        NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                        code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -5.8e-97], N[(R * N[ArcCos[N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[Abs[N[With[{TMP1 = N[(lambda2 - lambda1), $MachinePrecision], TMP2 = N[(2.0 * Pi), $MachinePrecision]}, TMP1 - Round[TMP1 / TMP2] * TMP2], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                        
                                                        \begin{array}{l}
                                                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                        [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                        \\
                                                        \begin{array}{l}
                                                        \mathbf{if}\;\lambda_1 \leq -5.8 \cdot 10^{-97}:\\
                                                        \;\;\;\;R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right)\\
                                                        
                                                        \mathbf{else}:\\
                                                        \;\;\;\;R \cdot \left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|\\
                                                        
                                                        
                                                        \end{array}
                                                        \end{array}
                                                        
                                                        Derivation
                                                        1. Split input into 2 regimes
                                                        2. if lambda1 < -5.7999999999999999e-97

                                                          1. Initial program 68.7%

                                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                          2. Step-by-step derivation
                                                            1. Simplified68.7%

                                                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                            2. Add Preprocessing
                                                            3. Taylor expanded in phi2 around 0 46.3%

                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                            4. Taylor expanded in phi1 around 0 29.7%

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

                                                            if -5.7999999999999999e-97 < lambda1

                                                            1. Initial program 79.0%

                                                              \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                            2. Step-by-step derivation
                                                              1. Simplified79.0%

                                                                \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                              2. Add Preprocessing
                                                              3. Taylor expanded in phi2 around 0 42.2%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                              4. Taylor expanded in phi1 around 0 21.5%

                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                              5. Step-by-step derivation
                                                                1. acos-cos20.6%

                                                                  \[\leadsto R \cdot \color{blue}{\left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|} \]
                                                              6. Applied egg-rr20.6%

                                                                \[\leadsto R \cdot \color{blue}{\left|\left(\left(\lambda_2 - \lambda_1\right) \mathsf{rem} \left(2 \cdot \pi\right)\right)\right|} \]
                                                            3. Recombined 2 regimes into one program.
                                                            4. Add Preprocessing

                                                            Alternative 20: 26.2% accurate, 2.9× speedup?

                                                            \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -0.038:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_2\\ \end{array} \end{array} \]
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            (FPCore (R lambda1 lambda2 phi1 phi2)
                                                             :precision binary64
                                                             (if (<= lambda1 -0.038)
                                                               (* R (acos (cos lambda1)))
                                                               (* R (acos (cos lambda2)))))
                                                            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                            	double tmp;
                                                            	if (lambda1 <= -0.038) {
                                                            		tmp = R * acos(cos(lambda1));
                                                            	} else {
                                                            		tmp = R * acos(cos(lambda2));
                                                            	}
                                                            	return tmp;
                                                            }
                                                            
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            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 <= (-0.038d0)) then
                                                                    tmp = r * acos(cos(lambda1))
                                                                else
                                                                    tmp = r * acos(cos(lambda2))
                                                                end if
                                                                code = tmp
                                                            end function
                                                            
                                                            assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                            assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                            public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                            	double tmp;
                                                            	if (lambda1 <= -0.038) {
                                                            		tmp = R * Math.acos(Math.cos(lambda1));
                                                            	} else {
                                                            		tmp = R * Math.acos(Math.cos(lambda2));
                                                            	}
                                                            	return tmp;
                                                            }
                                                            
                                                            [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                            [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                            def code(R, lambda1, lambda2, phi1, phi2):
                                                            	tmp = 0
                                                            	if lambda1 <= -0.038:
                                                            		tmp = R * math.acos(math.cos(lambda1))
                                                            	else:
                                                            		tmp = R * math.acos(math.cos(lambda2))
                                                            	return tmp
                                                            
                                                            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                            function code(R, lambda1, lambda2, phi1, phi2)
                                                            	tmp = 0.0
                                                            	if (lambda1 <= -0.038)
                                                            		tmp = Float64(R * acos(cos(lambda1)));
                                                            	else
                                                            		tmp = Float64(R * acos(cos(lambda2)));
                                                            	end
                                                            	return tmp
                                                            end
                                                            
                                                            R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                            R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                            function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                            	tmp = 0.0;
                                                            	if (lambda1 <= -0.038)
                                                            		tmp = R * acos(cos(lambda1));
                                                            	else
                                                            		tmp = R * acos(cos(lambda2));
                                                            	end
                                                            	tmp_2 = tmp;
                                                            end
                                                            
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                            code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -0.038], N[(R * N[ArcCos[N[Cos[lambda1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[ArcCos[N[Cos[lambda2], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
                                                            
                                                            \begin{array}{l}
                                                            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                            \\
                                                            \begin{array}{l}
                                                            \mathbf{if}\;\lambda_1 \leq -0.038:\\
                                                            \;\;\;\;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 lambda1 < -0.0379999999999999991

                                                              1. Initial program 64.4%

                                                                \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                              2. Step-by-step derivation
                                                                1. Simplified64.4%

                                                                  \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                2. Add Preprocessing
                                                                3. Taylor expanded in phi2 around 0 43.9%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                4. Taylor expanded in phi1 around 0 32.4%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                5. Taylor expanded in lambda2 around 0 32.5%

                                                                  \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(-\lambda_1\right)} \]
                                                                6. Step-by-step derivation
                                                                  1. cos-neg32.5%

                                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]
                                                                7. Simplified32.5%

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

                                                                if -0.0379999999999999991 < lambda1

                                                                1. Initial program 79.0%

                                                                  \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                2. Step-by-step derivation
                                                                  1. Simplified79.0%

                                                                    \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                  2. Add Preprocessing
                                                                  3. Taylor expanded in phi2 around 0 43.5%

                                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                  4. Taylor expanded in phi1 around 0 21.7%

                                                                    \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                  5. Taylor expanded in lambda1 around 0 15.4%

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

                                                                Alternative 21: 19.1% accurate, 2.9× speedup?

                                                                \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -2 \cdot 10^{+37}:\\ \;\;\;\;R \cdot \cos^{-1} \cos \lambda_1\\ \mathbf{else}:\\ \;\;\;\;R \cdot \left(\lambda_2 - \lambda_1\right)\\ \end{array} \end{array} \]
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                 :precision binary64
                                                                 (if (<= lambda1 -2e+37) (* R (acos (cos lambda1))) (* R (- lambda2 lambda1))))
                                                                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                	double tmp;
                                                                	if (lambda1 <= -2e+37) {
                                                                		tmp = R * acos(cos(lambda1));
                                                                	} else {
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	}
                                                                	return tmp;
                                                                }
                                                                
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                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 <= (-2d+37)) then
                                                                        tmp = r * acos(cos(lambda1))
                                                                    else
                                                                        tmp = r * (lambda2 - lambda1)
                                                                    end if
                                                                    code = tmp
                                                                end function
                                                                
                                                                assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                	double tmp;
                                                                	if (lambda1 <= -2e+37) {
                                                                		tmp = R * Math.acos(Math.cos(lambda1));
                                                                	} else {
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	}
                                                                	return tmp;
                                                                }
                                                                
                                                                [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                def code(R, lambda1, lambda2, phi1, phi2):
                                                                	tmp = 0
                                                                	if lambda1 <= -2e+37:
                                                                		tmp = R * math.acos(math.cos(lambda1))
                                                                	else:
                                                                		tmp = R * (lambda2 - lambda1)
                                                                	return tmp
                                                                
                                                                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                function code(R, lambda1, lambda2, phi1, phi2)
                                                                	tmp = 0.0
                                                                	if (lambda1 <= -2e+37)
                                                                		tmp = Float64(R * acos(cos(lambda1)));
                                                                	else
                                                                		tmp = Float64(R * Float64(lambda2 - lambda1));
                                                                	end
                                                                	return tmp
                                                                end
                                                                
                                                                R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                                	tmp = 0.0;
                                                                	if (lambda1 <= -2e+37)
                                                                		tmp = R * acos(cos(lambda1));
                                                                	else
                                                                		tmp = R * (lambda2 - lambda1);
                                                                	end
                                                                	tmp_2 = tmp;
                                                                end
                                                                
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -2e+37], N[(R * N[ArcCos[N[Cos[lambda1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]]
                                                                
                                                                \begin{array}{l}
                                                                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                                [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                                \\
                                                                \begin{array}{l}
                                                                \mathbf{if}\;\lambda_1 \leq -2 \cdot 10^{+37}:\\
                                                                \;\;\;\;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 < -1.99999999999999991e37

                                                                  1. Initial program 66.6%

                                                                    \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                  2. Step-by-step derivation
                                                                    1. Simplified66.6%

                                                                      \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                    2. Add Preprocessing
                                                                    3. Taylor expanded in phi2 around 0 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 33.0%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                    5. Taylor expanded in lambda2 around 0 33.1%

                                                                      \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(-\lambda_1\right)} \]
                                                                    6. Step-by-step derivation
                                                                      1. cos-neg33.1%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \lambda_1} \]
                                                                    7. Simplified33.1%

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

                                                                    if -1.99999999999999991e37 < lambda1

                                                                    1. Initial program 77.9%

                                                                      \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                    2. Step-by-step derivation
                                                                      1. Simplified77.9%

                                                                        \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                      2. Add Preprocessing
                                                                      3. Taylor expanded in phi2 around 0 43.4%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                      4. Taylor expanded in phi1 around 0 22.0%

                                                                        \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                      5. Taylor expanded in lambda2 around 0 7.6%

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

                                                                    Alternative 22: 26.3% accurate, 3.0× speedup?

                                                                    \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right) \end{array} \]
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                     :precision binary64
                                                                     (* R (acos (cos (- lambda2 lambda1)))))
                                                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                    assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                    double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                    	return R * acos(cos((lambda2 - lambda1)));
                                                                    }
                                                                    
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    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
                                                                    
                                                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                    assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                    public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                    	return R * Math.acos(Math.cos((lambda2 - lambda1)));
                                                                    }
                                                                    
                                                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                    def code(R, lambda1, lambda2, phi1, phi2):
                                                                    	return R * math.acos(math.cos((lambda2 - lambda1)))
                                                                    
                                                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                    function code(R, lambda1, lambda2, phi1, phi2)
                                                                    	return Float64(R * acos(cos(Float64(lambda2 - lambda1))))
                                                                    end
                                                                    
                                                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                    R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                    function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                    	tmp = R * acos(cos((lambda2 - lambda1)));
                                                                    end
                                                                    
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                    code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[ArcCos[N[Cos[N[(lambda2 - lambda1), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                                                                    
                                                                    \begin{array}{l}
                                                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                                    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                                    \\
                                                                    R \cdot \cos^{-1} \cos \left(\lambda_2 - \lambda_1\right)
                                                                    \end{array}
                                                                    
                                                                    Derivation
                                                                    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 43.6%

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

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

                                                                      Alternative 23: 8.8% accurate, 68.0× speedup?

                                                                      \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -6.6 \cdot 10^{-132}:\\ \;\;\;\;\lambda_1 \cdot \left(-R\right)\\ \mathbf{else}:\\ \;\;\;\;\lambda_2 \cdot R\\ \end{array} \end{array} \]
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                       :precision binary64
                                                                       (if (<= lambda1 -6.6e-132) (* lambda1 (- R)) (* lambda2 R)))
                                                                      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                      assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                      double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                      	double tmp;
                                                                      	if (lambda1 <= -6.6e-132) {
                                                                      		tmp = lambda1 * -R;
                                                                      	} else {
                                                                      		tmp = lambda2 * R;
                                                                      	}
                                                                      	return tmp;
                                                                      }
                                                                      
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      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 <= (-6.6d-132)) then
                                                                              tmp = lambda1 * -r
                                                                          else
                                                                              tmp = lambda2 * r
                                                                          end if
                                                                          code = tmp
                                                                      end function
                                                                      
                                                                      assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                      assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                      public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                      	double tmp;
                                                                      	if (lambda1 <= -6.6e-132) {
                                                                      		tmp = lambda1 * -R;
                                                                      	} else {
                                                                      		tmp = lambda2 * R;
                                                                      	}
                                                                      	return tmp;
                                                                      }
                                                                      
                                                                      [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                      [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                      def code(R, lambda1, lambda2, phi1, phi2):
                                                                      	tmp = 0
                                                                      	if lambda1 <= -6.6e-132:
                                                                      		tmp = lambda1 * -R
                                                                      	else:
                                                                      		tmp = lambda2 * R
                                                                      	return tmp
                                                                      
                                                                      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                      R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                      function code(R, lambda1, lambda2, phi1, phi2)
                                                                      	tmp = 0.0
                                                                      	if (lambda1 <= -6.6e-132)
                                                                      		tmp = Float64(lambda1 * Float64(-R));
                                                                      	else
                                                                      		tmp = Float64(lambda2 * R);
                                                                      	end
                                                                      	return tmp
                                                                      end
                                                                      
                                                                      R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                      R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                      function tmp_2 = code(R, lambda1, lambda2, phi1, phi2)
                                                                      	tmp = 0.0;
                                                                      	if (lambda1 <= -6.6e-132)
                                                                      		tmp = lambda1 * -R;
                                                                      	else
                                                                      		tmp = lambda2 * R;
                                                                      	end
                                                                      	tmp_2 = tmp;
                                                                      end
                                                                      
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                      code[R_, lambda1_, lambda2_, phi1_, phi2_] := If[LessEqual[lambda1, -6.6e-132], N[(lambda1 * (-R)), $MachinePrecision], N[(lambda2 * R), $MachinePrecision]]
                                                                      
                                                                      \begin{array}{l}
                                                                      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                                      [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                                      \\
                                                                      \begin{array}{l}
                                                                      \mathbf{if}\;\lambda_1 \leq -6.6 \cdot 10^{-132}:\\
                                                                      \;\;\;\;\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 < -6.5999999999999994e-132

                                                                        1. Initial program 70.4%

                                                                          \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                        2. Step-by-step derivation
                                                                          1. Simplified70.5%

                                                                            \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                          2. Add Preprocessing
                                                                          3. Taylor expanded in phi2 around 0 46.6%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                          4. Taylor expanded in phi1 around 0 28.7%

                                                                            \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                          5. Taylor expanded in lambda2 around 0 11.4%

                                                                            \[\leadsto \color{blue}{-1 \cdot \left(R \cdot \lambda_1\right)} \]
                                                                          6. Step-by-step derivation
                                                                            1. associate-*r*11.4%

                                                                              \[\leadsto \color{blue}{\left(-1 \cdot R\right) \cdot \lambda_1} \]
                                                                            2. mul-1-neg11.4%

                                                                              \[\leadsto \color{blue}{\left(-R\right)} \cdot \lambda_1 \]
                                                                          7. Simplified11.4%

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

                                                                          if -6.5999999999999994e-132 < lambda1

                                                                          1. Initial program 78.4%

                                                                            \[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R \]
                                                                          2. Step-by-step derivation
                                                                            1. Simplified78.4%

                                                                              \[\leadsto \color{blue}{R \cdot \cos^{-1} \left(\mathsf{fma}\left(\cos \phi_1 \cdot \cos \phi_2, \cos \left(\lambda_2 - \lambda_1\right), \sin \phi_1 \cdot \sin \phi_2\right)\right)} \]
                                                                            2. Add Preprocessing
                                                                            3. Taylor expanded in phi2 around 0 42.0%

                                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                            4. Taylor expanded in phi1 around 0 21.8%

                                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\cos \left(\lambda_2 - \lambda_1\right)} \]
                                                                            5. Taylor expanded in lambda2 around inf 6.1%

                                                                              \[\leadsto \color{blue}{R \cdot \lambda_2} \]
                                                                            6. Step-by-step derivation
                                                                              1. *-commutative6.1%

                                                                                \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                            7. Simplified6.1%

                                                                              \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                          3. Recombined 2 regimes into one program.
                                                                          4. Final simplification7.9%

                                                                            \[\leadsto \begin{array}{l} \mathbf{if}\;\lambda_1 \leq -6.6 \cdot 10^{-132}:\\ \;\;\;\;\lambda_1 \cdot \left(-R\right)\\ \mathbf{else}:\\ \;\;\;\;\lambda_2 \cdot R\\ \end{array} \]
                                                                          5. Add Preprocessing

                                                                          Alternative 24: 9.0% accurate, 122.6× speedup?

                                                                          \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ R \cdot \left(\lambda_2 - \lambda_1\right) \end{array} \]
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          (FPCore (R lambda1 lambda2 phi1 phi2)
                                                                           :precision binary64
                                                                           (* R (- lambda2 lambda1)))
                                                                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                          assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                          double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                          	return R * (lambda2 - lambda1);
                                                                          }
                                                                          
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          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
                                                                          
                                                                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                          assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                          public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                          	return R * (lambda2 - lambda1);
                                                                          }
                                                                          
                                                                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                          def code(R, lambda1, lambda2, phi1, phi2):
                                                                          	return R * (lambda2 - lambda1)
                                                                          
                                                                          R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                          R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                          function code(R, lambda1, lambda2, phi1, phi2)
                                                                          	return Float64(R * Float64(lambda2 - lambda1))
                                                                          end
                                                                          
                                                                          R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                          R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                          function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                          	tmp = R * (lambda2 - lambda1);
                                                                          end
                                                                          
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                          code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(R * N[(lambda2 - lambda1), $MachinePrecision]), $MachinePrecision]
                                                                          
                                                                          \begin{array}{l}
                                                                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                                          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                                          \\
                                                                          R \cdot \left(\lambda_2 - \lambda_1\right)
                                                                          \end{array}
                                                                          
                                                                          Derivation
                                                                          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 43.6%

                                                                              \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                            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 7.0%

                                                                              \[\leadsto R \cdot \color{blue}{\left(\lambda_2 - \lambda_1\right)} \]
                                                                            6. Add Preprocessing

                                                                            Alternative 25: 6.8% accurate, 204.3× speedup?

                                                                            \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\ [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \lambda_2 \cdot R \end{array} \]
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            (FPCore (R lambda1 lambda2 phi1 phi2) :precision binary64 (* lambda2 R))
                                                                            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
                                                                            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                            	return lambda2 * R;
                                                                            }
                                                                            
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            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
                                                                            
                                                                            assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                            assert R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2;
                                                                            public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
                                                                            	return lambda2 * R;
                                                                            }
                                                                            
                                                                            [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                            [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
                                                                            def code(R, lambda1, lambda2, phi1, phi2):
                                                                            	return lambda2 * R
                                                                            
                                                                            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
                                                                            function code(R, lambda1, lambda2, phi1, phi2)
                                                                            	return Float64(lambda2 * R)
                                                                            end
                                                                            
                                                                            R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                            R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
                                                                            function tmp = code(R, lambda1, lambda2, phi1, phi2)
                                                                            	tmp = lambda2 * R;
                                                                            end
                                                                            
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
                                                                            code[R_, lambda1_, lambda2_, phi1_, phi2_] := N[(lambda2 * R), $MachinePrecision]
                                                                            
                                                                            \begin{array}{l}
                                                                            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\\\
                                                                            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
                                                                            \\
                                                                            \lambda_2 \cdot R
                                                                            \end{array}
                                                                            
                                                                            Derivation
                                                                            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 43.6%

                                                                                \[\leadsto R \cdot \cos^{-1} \color{blue}{\left(\cos \phi_1 \cdot \cos \left(\lambda_2 - \lambda_1\right)\right)} \]
                                                                              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 5.7%

                                                                                \[\leadsto \color{blue}{R \cdot \lambda_2} \]
                                                                              6. Step-by-step derivation
                                                                                1. *-commutative5.7%

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

                                                                                \[\leadsto \color{blue}{\lambda_2 \cdot R} \]
                                                                              8. Add Preprocessing

                                                                              Reproduce

                                                                              ?
                                                                              herbie shell --seed 2024107 
                                                                              (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))