Equirectangular approximation to distance on a great circle

Percentage Accurate: 59.8% → 94.8%
Time: 9.7s
Alternatives: 12
Speedup: 2.5×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\\ R \cdot \sqrt{t\_0 \cdot t\_0 + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \end{array} \end{array} \]
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (let* ((t_0 (* (- lambda1 lambda2) (cos (/ (+ phi1 phi2) 2.0)))))
   (* R (sqrt (+ (* t_0 t_0) (* (- phi1 phi2) (- phi1 phi2)))))))
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0));
	return R * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
}
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
    t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0d0))
    code = r * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))))
end function
public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double t_0 = (lambda1 - lambda2) * Math.cos(((phi1 + phi2) / 2.0));
	return R * Math.sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
}
def code(R, lambda1, lambda2, phi1, phi2):
	t_0 = (lambda1 - lambda2) * math.cos(((phi1 + phi2) / 2.0))
	return R * math.sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))))
function code(R, lambda1, lambda2, phi1, phi2)
	t_0 = Float64(Float64(lambda1 - lambda2) * cos(Float64(Float64(phi1 + phi2) / 2.0)))
	return Float64(R * sqrt(Float64(Float64(t_0 * t_0) + Float64(Float64(phi1 - phi2) * Float64(phi1 - phi2)))))
end
function tmp = code(R, lambda1, lambda2, phi1, phi2)
	t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0));
	tmp = R * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
end
code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[(lambda1 - lambda2), $MachinePrecision] * N[Cos[N[(N[(phi1 + phi2), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, N[(R * N[Sqrt[N[(N[(t$95$0 * t$95$0), $MachinePrecision] + N[(N[(phi1 - phi2), $MachinePrecision] * N[(phi1 - phi2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\\
R \cdot \sqrt{t\_0 \cdot t\_0 + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}
\end{array}
\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 12 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: 59.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\\ R \cdot \sqrt{t\_0 \cdot t\_0 + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \end{array} \end{array} \]
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (let* ((t_0 (* (- lambda1 lambda2) (cos (/ (+ phi1 phi2) 2.0)))))
   (* R (sqrt (+ (* t_0 t_0) (* (- phi1 phi2) (- phi1 phi2)))))))
double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0));
	return R * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
}
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
    t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0d0))
    code = r * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))))
end function
public static double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
	double t_0 = (lambda1 - lambda2) * Math.cos(((phi1 + phi2) / 2.0));
	return R * Math.sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
}
def code(R, lambda1, lambda2, phi1, phi2):
	t_0 = (lambda1 - lambda2) * math.cos(((phi1 + phi2) / 2.0))
	return R * math.sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))))
function code(R, lambda1, lambda2, phi1, phi2)
	t_0 = Float64(Float64(lambda1 - lambda2) * cos(Float64(Float64(phi1 + phi2) / 2.0)))
	return Float64(R * sqrt(Float64(Float64(t_0 * t_0) + Float64(Float64(phi1 - phi2) * Float64(phi1 - phi2)))))
end
function tmp = code(R, lambda1, lambda2, phi1, phi2)
	t_0 = (lambda1 - lambda2) * cos(((phi1 + phi2) / 2.0));
	tmp = R * sqrt(((t_0 * t_0) + ((phi1 - phi2) * (phi1 - phi2))));
end
code[R_, lambda1_, lambda2_, phi1_, phi2_] := Block[{t$95$0 = N[(N[(lambda1 - lambda2), $MachinePrecision] * N[Cos[N[(N[(phi1 + phi2), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, N[(R * N[Sqrt[N[(N[(t$95$0 * t$95$0), $MachinePrecision] + N[(N[(phi1 - phi2), $MachinePrecision] * N[(phi1 - phi2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\\
R \cdot \sqrt{t\_0 \cdot t\_0 + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}
\end{array}
\end{array}

Alternative 1: 94.8% accurate, 1.2× speedup?

\[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq 9.2 \cdot 10^{-39}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \cos \left(-0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\\ \end{array} \end{array} \]
NOTE: R, lambda1, lambda2, phi1, and phi2 should be sorted in increasing order before calling this function.
(FPCore (R lambda1 lambda2 phi1 phi2)
 :precision binary64
 (if (<= phi2 9.2e-39)
   (* R (hypot (* (cos (* 0.5 phi1)) (- lambda1 lambda2)) phi1))
   (* R (hypot (- phi1 phi2) (* (cos (* -0.5 phi2)) (- lambda1 lambda2))))))
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 <= 9.2e-39) {
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * hypot((phi1 - phi2), (cos((-0.5 * phi2)) * (lambda1 - lambda2)));
	}
	return tmp;
}
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 <= 9.2e-39) {
		tmp = R * Math.hypot((Math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * Math.hypot((phi1 - phi2), (Math.cos((-0.5 * phi2)) * (lambda1 - lambda2)));
	}
	return tmp;
}
[R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
def code(R, lambda1, lambda2, phi1, phi2):
	tmp = 0
	if phi2 <= 9.2e-39:
		tmp = R * math.hypot((math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1)
	else:
		tmp = R * math.hypot((phi1 - phi2), (math.cos((-0.5 * phi2)) * (lambda1 - lambda2)))
	return tmp
R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
function code(R, lambda1, lambda2, phi1, phi2)
	tmp = 0.0
	if (phi2 <= 9.2e-39)
		tmp = Float64(R * hypot(Float64(cos(Float64(0.5 * phi1)) * Float64(lambda1 - lambda2)), phi1));
	else
		tmp = Float64(R * hypot(Float64(phi1 - phi2), Float64(cos(Float64(-0.5 * phi2)) * Float64(lambda1 - lambda2))));
	end
	return tmp
end
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 <= 9.2e-39)
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	else
		tmp = R * hypot((phi1 - phi2), (cos((-0.5 * phi2)) * (lambda1 - lambda2)));
	end
	tmp_2 = tmp;
end
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, 9.2e-39], N[(R * N[Sqrt[N[(N[Cos[N[(0.5 * phi1), $MachinePrecision]], $MachinePrecision] * N[(lambda1 - lambda2), $MachinePrecision]), $MachinePrecision] ^ 2 + phi1 ^ 2], $MachinePrecision]), $MachinePrecision], N[(R * N[Sqrt[N[(phi1 - phi2), $MachinePrecision] ^ 2 + N[(N[Cos[N[(-0.5 * phi2), $MachinePrecision]], $MachinePrecision] * N[(lambda1 - lambda2), $MachinePrecision]), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
\\
\begin{array}{l}
\mathbf{if}\;\phi_2 \leq 9.2 \cdot 10^{-39}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\

\mathbf{else}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \cos \left(-0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if phi2 < 9.20000000000000033e-39

    1. Initial program 55.2%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi2 around 0

      \[\leadsto R \cdot \color{blue}{\sqrt{{\cos \left(\frac{1}{2} \cdot \phi_1\right)}^{2} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right)} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}} \]
      2. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right) \cdot \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      3. unswap-sqrN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      4. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) + \color{blue}{\phi_1 \cdot \phi_1}} \]
      5. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]
      6. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
      7. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      8. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \color{blue}{\left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      9. lower--.f6479.4

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
    5. Applied rewrites79.4%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]

    if 9.20000000000000033e-39 < phi2

    1. Initial program 55.3%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-sqrt.f64N/A

        \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
      2. lift-+.f64N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
      3. +-commutativeN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
      4. lift-*.f64N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
      5. lift-*.f64N/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
      6. pow2N/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
      7. pow-to-expN/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
      8. exp-lft-sqrN/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
      9. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
    4. Applied rewrites47.8%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
    5. Taylor expanded in phi1 around 0

      \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
    6. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
      2. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_2\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right) \]
      3. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_2\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right) \]
      4. lower--.f6487.1

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \cos \left(-0.5 \cdot \phi_2\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right) \]
    7. Applied rewrites87.1%

      \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(-0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 90.9% accurate, 1.2× speedup?

\[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.6 \cdot 10^{-6}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right)\\ \end{array} \end{array} \]
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 -1.6e-6)
   (* R (hypot (* (cos (* 0.5 phi1)) (- lambda1 lambda2)) phi1))
   (* R (hypot (* (cos (* 0.5 phi2)) (- lambda1 lambda2)) 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 <= -1.6e-6) {
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * hypot((cos((0.5 * phi2)) * (lambda1 - lambda2)), phi2);
	}
	return tmp;
}
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 <= -1.6e-6) {
		tmp = R * Math.hypot((Math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * Math.hypot((Math.cos((0.5 * phi2)) * (lambda1 - lambda2)), phi2);
	}
	return tmp;
}
[R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
def code(R, lambda1, lambda2, phi1, phi2):
	tmp = 0
	if phi1 <= -1.6e-6:
		tmp = R * math.hypot((math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1)
	else:
		tmp = R * math.hypot((math.cos((0.5 * phi2)) * (lambda1 - lambda2)), phi2)
	return tmp
R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
function code(R, lambda1, lambda2, phi1, phi2)
	tmp = 0.0
	if (phi1 <= -1.6e-6)
		tmp = Float64(R * hypot(Float64(cos(Float64(0.5 * phi1)) * Float64(lambda1 - lambda2)), phi1));
	else
		tmp = Float64(R * hypot(Float64(cos(Float64(0.5 * phi2)) * Float64(lambda1 - lambda2)), phi2));
	end
	return tmp
end
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 <= -1.6e-6)
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	else
		tmp = R * hypot((cos((0.5 * phi2)) * (lambda1 - lambda2)), phi2);
	end
	tmp_2 = tmp;
end
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, -1.6e-6], N[(R * N[Sqrt[N[(N[Cos[N[(0.5 * phi1), $MachinePrecision]], $MachinePrecision] * N[(lambda1 - lambda2), $MachinePrecision]), $MachinePrecision] ^ 2 + phi1 ^ 2], $MachinePrecision]), $MachinePrecision], N[(R * N[Sqrt[N[(N[Cos[N[(0.5 * phi2), $MachinePrecision]], $MachinePrecision] * N[(lambda1 - lambda2), $MachinePrecision]), $MachinePrecision] ^ 2 + phi2 ^ 2], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
\\
\begin{array}{l}
\mathbf{if}\;\phi_1 \leq -1.6 \cdot 10^{-6}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\

\mathbf{else}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if phi1 < -1.5999999999999999e-6

    1. Initial program 45.5%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi2 around 0

      \[\leadsto R \cdot \color{blue}{\sqrt{{\cos \left(\frac{1}{2} \cdot \phi_1\right)}^{2} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right)} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}} \]
      2. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right) \cdot \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      3. unswap-sqrN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      4. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) + \color{blue}{\phi_1 \cdot \phi_1}} \]
      5. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]
      6. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
      7. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      8. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \color{blue}{\left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      9. lower--.f6473.1

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
    5. Applied rewrites73.1%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]

    if -1.5999999999999999e-6 < phi1

    1. Initial program 58.4%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto R \cdot \color{blue}{\sqrt{{\cos \left(\frac{1}{2} \cdot \phi_2\right)}^{2} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_2}^{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_2\right)\right)} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_2}^{2}} \]
      2. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_2\right)\right) \cdot \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_2}^{2}} \]
      3. unswap-sqrN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_2}^{2}} \]
      4. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) + \color{blue}{\phi_2 \cdot \phi_2}} \]
      5. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right)} \]
      6. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right)}, \phi_2\right) \]
      7. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right) \]
      8. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right) \]
      9. lower--.f6479.0

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_2\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}, \phi_2\right) \]
    5. Applied rewrites79.0%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_2\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_2\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 89.3% accurate, 1.2× speedup?

\[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_2 \leq 9.2 \cdot 10^{-39}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \lambda_2\right)\\ \end{array} \end{array} \]
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 9.2e-39)
   (* R (hypot (* (cos (* 0.5 phi1)) (- lambda1 lambda2)) phi1))
   (* R (hypot (- phi1 phi2) (- lambda1 lambda2)))))
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 <= 9.2e-39) {
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * hypot((phi1 - phi2), (lambda1 - lambda2));
	}
	return tmp;
}
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 <= 9.2e-39) {
		tmp = R * Math.hypot((Math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	} else {
		tmp = R * Math.hypot((phi1 - phi2), (lambda1 - lambda2));
	}
	return tmp;
}
[R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
def code(R, lambda1, lambda2, phi1, phi2):
	tmp = 0
	if phi2 <= 9.2e-39:
		tmp = R * math.hypot((math.cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1)
	else:
		tmp = R * math.hypot((phi1 - phi2), (lambda1 - lambda2))
	return tmp
R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
function code(R, lambda1, lambda2, phi1, phi2)
	tmp = 0.0
	if (phi2 <= 9.2e-39)
		tmp = Float64(R * hypot(Float64(cos(Float64(0.5 * phi1)) * Float64(lambda1 - lambda2)), phi1));
	else
		tmp = Float64(R * hypot(Float64(phi1 - phi2), Float64(lambda1 - lambda2)));
	end
	return tmp
end
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 <= 9.2e-39)
		tmp = R * hypot((cos((0.5 * phi1)) * (lambda1 - lambda2)), phi1);
	else
		tmp = R * hypot((phi1 - phi2), (lambda1 - lambda2));
	end
	tmp_2 = tmp;
end
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, 9.2e-39], N[(R * N[Sqrt[N[(N[Cos[N[(0.5 * phi1), $MachinePrecision]], $MachinePrecision] * N[(lambda1 - lambda2), $MachinePrecision]), $MachinePrecision] ^ 2 + phi1 ^ 2], $MachinePrecision]), $MachinePrecision], N[(R * N[Sqrt[N[(phi1 - phi2), $MachinePrecision] ^ 2 + N[(lambda1 - lambda2), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
\\
\begin{array}{l}
\mathbf{if}\;\phi_2 \leq 9.2 \cdot 10^{-39}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)\\

\mathbf{else}:\\
\;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \lambda_2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if phi2 < 9.20000000000000033e-39

    1. Initial program 55.2%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi2 around 0

      \[\leadsto R \cdot \color{blue}{\sqrt{{\cos \left(\frac{1}{2} \cdot \phi_1\right)}^{2} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right)} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}} \]
      2. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right) \cdot \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      3. unswap-sqrN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
      4. unpow2N/A

        \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) + \color{blue}{\phi_1 \cdot \phi_1}} \]
      5. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]
      6. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
      7. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      8. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \color{blue}{\left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
      9. lower--.f6479.4

        \[\leadsto R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
    5. Applied rewrites79.4%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]

    if 9.20000000000000033e-39 < phi2

    1. Initial program 55.3%

      \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-sqrt.f64N/A

        \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
      2. lift-+.f64N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
      3. +-commutativeN/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
      4. lift-*.f64N/A

        \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
      5. lift-*.f64N/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
      6. pow2N/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
      7. pow-to-expN/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
      8. exp-lft-sqrN/A

        \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
      9. lower-hypot.f64N/A

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
    4. Applied rewrites47.8%

      \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
    5. Taylor expanded in phi2 around 0

      \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right) + \cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right) + \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
      2. lower-fma.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)}\right) \]
      3. lower-cos.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
      4. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
      5. lower--.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \color{blue}{\lambda_1 - \lambda_2}, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
      6. associate-*r*N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
      7. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
      8. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
      9. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \color{blue}{\left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
      10. lower-sin.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\color{blue}{\sin \left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
      11. lower-*.f64N/A

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
      12. lower--.f6466.2

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right)\right)\right) \]
    7. Applied rewrites66.2%

      \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
    8. Taylor expanded in phi1 around 0

      \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
    9. Step-by-step derivation
      1. Applied rewrites76.8%

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
    10. Recombined 2 regimes into one program.
    11. Add Preprocessing

    Alternative 4: 81.2% accurate, 2.4× speedup?

    \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -4.6 \cdot 10^{+46}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, -\lambda_2\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(-\phi_2, \lambda_1 - \lambda_2\right)\\ \end{array} \end{array} \]
    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 -4.6e+46)
       (* R (hypot (- phi1 phi2) (- lambda2)))
       (* R (hypot (- phi2) (- lambda1 lambda2)))))
    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 <= -4.6e+46) {
    		tmp = R * hypot((phi1 - phi2), -lambda2);
    	} else {
    		tmp = R * hypot(-phi2, (lambda1 - lambda2));
    	}
    	return tmp;
    }
    
    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 <= -4.6e+46) {
    		tmp = R * Math.hypot((phi1 - phi2), -lambda2);
    	} else {
    		tmp = R * Math.hypot(-phi2, (lambda1 - lambda2));
    	}
    	return tmp;
    }
    
    [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
    def code(R, lambda1, lambda2, phi1, phi2):
    	tmp = 0
    	if phi1 <= -4.6e+46:
    		tmp = R * math.hypot((phi1 - phi2), -lambda2)
    	else:
    		tmp = R * math.hypot(-phi2, (lambda1 - lambda2))
    	return tmp
    
    R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
    function code(R, lambda1, lambda2, phi1, phi2)
    	tmp = 0.0
    	if (phi1 <= -4.6e+46)
    		tmp = Float64(R * hypot(Float64(phi1 - phi2), Float64(-lambda2)));
    	else
    		tmp = Float64(R * hypot(Float64(-phi2), Float64(lambda1 - lambda2)));
    	end
    	return tmp
    end
    
    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 <= -4.6e+46)
    		tmp = R * hypot((phi1 - phi2), -lambda2);
    	else
    		tmp = R * hypot(-phi2, (lambda1 - lambda2));
    	end
    	tmp_2 = tmp;
    end
    
    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, -4.6e+46], N[(R * N[Sqrt[N[(phi1 - phi2), $MachinePrecision] ^ 2 + (-lambda2) ^ 2], $MachinePrecision]), $MachinePrecision], N[(R * N[Sqrt[(-phi2) ^ 2 + N[(lambda1 - lambda2), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;\phi_1 \leq -4.6 \cdot 10^{+46}:\\
    \;\;\;\;R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, -\lambda_2\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;R \cdot \mathsf{hypot}\left(-\phi_2, \lambda_1 - \lambda_2\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if phi1 < -4.6000000000000001e46

      1. Initial program 42.9%

        \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-sqrt.f64N/A

          \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
        2. lift-+.f64N/A

          \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
        3. +-commutativeN/A

          \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
        4. lift-*.f64N/A

          \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
        5. lift-*.f64N/A

          \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
        6. pow2N/A

          \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
        7. pow-to-expN/A

          \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
        8. exp-lft-sqrN/A

          \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
        9. lower-hypot.f64N/A

          \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
      4. Applied rewrites44.2%

        \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
      5. Taylor expanded in phi2 around 0

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right) + \cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
      6. Step-by-step derivation
        1. +-commutativeN/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right) + \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
        2. lower-fma.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)}\right) \]
        3. lower-cos.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
        4. lower-*.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
        5. lower--.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \color{blue}{\lambda_1 - \lambda_2}, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
        6. associate-*r*N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
        7. lower-*.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
        8. lower-*.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
        9. lower-*.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \color{blue}{\left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
        10. lower-sin.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\color{blue}{\sin \left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
        11. lower-*.f64N/A

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
        12. lower--.f6475.9

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right)\right)\right) \]
      7. Applied rewrites75.9%

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
      8. Taylor expanded in phi1 around 0

        \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
      9. Step-by-step derivation
        1. Applied rewrites79.1%

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
        2. Taylor expanded in lambda1 around 0

          \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, -1 \cdot \lambda_2\right) \]
        3. Step-by-step derivation
          1. Applied rewrites76.6%

            \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, -\lambda_2\right) \]

          if -4.6000000000000001e46 < phi1

          1. Initial program 58.6%

            \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-sqrt.f64N/A

              \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
            2. lift-+.f64N/A

              \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
            3. +-commutativeN/A

              \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
            4. lift-*.f64N/A

              \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
            5. lift-*.f64N/A

              \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
            6. pow2N/A

              \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
            7. pow-to-expN/A

              \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
            8. exp-lft-sqrN/A

              \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
            9. lower-hypot.f64N/A

              \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
          4. Applied rewrites52.3%

            \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
          5. Taylor expanded in phi2 around 0

            \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right) + \cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
          6. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right) + \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
            2. lower-fma.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)}\right) \]
            3. lower-cos.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
            4. lower-*.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
            5. lower--.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \color{blue}{\lambda_1 - \lambda_2}, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
            6. associate-*r*N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
            7. lower-*.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
            8. lower-*.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
            9. lower-*.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \color{blue}{\left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
            10. lower-sin.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\color{blue}{\sin \left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
            11. lower-*.f64N/A

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
            12. lower--.f6479.5

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right)\right)\right) \]
          7. Applied rewrites79.5%

            \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
          8. Taylor expanded in phi1 around 0

            \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
          9. Step-by-step derivation
            1. Applied rewrites84.3%

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
            2. Taylor expanded in phi1 around 0

              \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-1 \cdot \phi_2}, \lambda_1 - \lambda_2\right) \]
            3. Step-by-step derivation
              1. mul-1-negN/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\mathsf{neg}\left(\phi_2\right)}, \lambda_1 - \lambda_2\right) \]
              2. lower-neg.f6469.3

                \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-\phi_2}, \lambda_1 - \lambda_2\right) \]
            4. Applied rewrites69.3%

              \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-\phi_2}, \lambda_1 - \lambda_2\right) \]
          10. Recombined 2 regimes into one program.
          11. Add Preprocessing

          Alternative 5: 79.8% accurate, 2.4× speedup?

          \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -3.3 \cdot 10^{+47}:\\ \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(-\phi_2, \lambda_1 - \lambda_2\right)\\ \end{array} \end{array} \]
          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 -3.3e+47)
             (* R (* phi1 (+ -1.0 (/ phi2 phi1))))
             (* R (hypot (- phi2) (- lambda1 lambda2)))))
          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 <= -3.3e+47) {
          		tmp = R * (phi1 * (-1.0 + (phi2 / phi1)));
          	} else {
          		tmp = R * hypot(-phi2, (lambda1 - lambda2));
          	}
          	return tmp;
          }
          
          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 <= -3.3e+47) {
          		tmp = R * (phi1 * (-1.0 + (phi2 / phi1)));
          	} else {
          		tmp = R * Math.hypot(-phi2, (lambda1 - lambda2));
          	}
          	return tmp;
          }
          
          [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
          def code(R, lambda1, lambda2, phi1, phi2):
          	tmp = 0
          	if phi1 <= -3.3e+47:
          		tmp = R * (phi1 * (-1.0 + (phi2 / phi1)))
          	else:
          		tmp = R * math.hypot(-phi2, (lambda1 - lambda2))
          	return tmp
          
          R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
          function code(R, lambda1, lambda2, phi1, phi2)
          	tmp = 0.0
          	if (phi1 <= -3.3e+47)
          		tmp = Float64(R * Float64(phi1 * Float64(-1.0 + Float64(phi2 / phi1))));
          	else
          		tmp = Float64(R * hypot(Float64(-phi2), Float64(lambda1 - lambda2)));
          	end
          	return tmp
          end
          
          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 <= -3.3e+47)
          		tmp = R * (phi1 * (-1.0 + (phi2 / phi1)));
          	else
          		tmp = R * hypot(-phi2, (lambda1 - lambda2));
          	end
          	tmp_2 = tmp;
          end
          
          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, -3.3e+47], N[(R * N[(phi1 * N[(-1.0 + N[(phi2 / phi1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(R * N[Sqrt[(-phi2) ^ 2 + N[(lambda1 - lambda2), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]
          
          \begin{array}{l}
          [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
          \\
          \begin{array}{l}
          \mathbf{if}\;\phi_1 \leq -3.3 \cdot 10^{+47}:\\
          \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;R \cdot \mathsf{hypot}\left(-\phi_2, \lambda_1 - \lambda_2\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if phi1 < -3.2999999999999999e47

            1. Initial program 42.9%

              \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
            2. Add Preprocessing
            3. Taylor expanded in phi1 around -inf

              \[\leadsto R \cdot \color{blue}{\left(-1 \cdot \left(\phi_1 \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)\right)} \]
            4. Step-by-step derivation
              1. associate-*r*N/A

                \[\leadsto R \cdot \color{blue}{\left(\left(-1 \cdot \phi_1\right) \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)} \]
              2. lower-*.f64N/A

                \[\leadsto R \cdot \color{blue}{\left(\left(-1 \cdot \phi_1\right) \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)} \]
              3. mul-1-negN/A

                \[\leadsto R \cdot \left(\color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right) \]
              4. lower-neg.f64N/A

                \[\leadsto R \cdot \left(\color{blue}{\left(-\phi_1\right)} \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right) \]
              5. mul-1-negN/A

                \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \left(1 + \color{blue}{\left(\mathsf{neg}\left(\frac{\phi_2}{\phi_1}\right)\right)}\right)\right) \]
              6. unsub-negN/A

                \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \color{blue}{\left(1 - \frac{\phi_2}{\phi_1}\right)}\right) \]
              7. lower--.f64N/A

                \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \color{blue}{\left(1 - \frac{\phi_2}{\phi_1}\right)}\right) \]
              8. lower-/.f6463.7

                \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \left(1 - \color{blue}{\frac{\phi_2}{\phi_1}}\right)\right) \]
            5. Applied rewrites63.7%

              \[\leadsto R \cdot \color{blue}{\left(\left(-\phi_1\right) \cdot \left(1 - \frac{\phi_2}{\phi_1}\right)\right)} \]

            if -3.2999999999999999e47 < phi1

            1. Initial program 58.6%

              \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-sqrt.f64N/A

                \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
              2. lift-+.f64N/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
              3. +-commutativeN/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
              4. lift-*.f64N/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
              5. lift-*.f64N/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
              6. pow2N/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
              7. pow-to-expN/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
              8. exp-lft-sqrN/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
              9. lower-hypot.f64N/A

                \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
            4. Applied rewrites52.3%

              \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
            5. Taylor expanded in phi2 around 0

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right) + \cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
            6. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right) + \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
              2. lower-fma.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)}\right) \]
              3. lower-cos.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              4. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              5. lower--.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \color{blue}{\lambda_1 - \lambda_2}, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              6. associate-*r*N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              7. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              8. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              9. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \color{blue}{\left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              10. lower-sin.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\color{blue}{\sin \left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              11. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              12. lower--.f6479.5

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right)\right)\right) \]
            7. Applied rewrites79.5%

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
            8. Taylor expanded in phi1 around 0

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
            9. Step-by-step derivation
              1. Applied rewrites84.3%

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
              2. Taylor expanded in phi1 around 0

                \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-1 \cdot \phi_2}, \lambda_1 - \lambda_2\right) \]
              3. Step-by-step derivation
                1. mul-1-negN/A

                  \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\mathsf{neg}\left(\phi_2\right)}, \lambda_1 - \lambda_2\right) \]
                2. lower-neg.f6469.3

                  \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-\phi_2}, \lambda_1 - \lambda_2\right) \]
              4. Applied rewrites69.3%

                \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{-\phi_2}, \lambda_1 - \lambda_2\right) \]
            10. Recombined 2 regimes into one program.
            11. Final simplification68.1%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -3.3 \cdot 10^{+47}:\\ \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \mathsf{hypot}\left(-\phi_2, \lambda_1 - \lambda_2\right)\\ \end{array} \]
            12. Add Preprocessing

            Alternative 6: 85.1% accurate, 2.5× speedup?

            \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \lambda_2\right) \end{array} \]
            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 (hypot (- phi1 phi2) (- lambda1 lambda2))))
            assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
            double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
            	return R * hypot((phi1 - phi2), (lambda1 - lambda2));
            }
            
            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.hypot((phi1 - phi2), (lambda1 - lambda2));
            }
            
            [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
            def code(R, lambda1, lambda2, phi1, phi2):
            	return R * math.hypot((phi1 - phi2), (lambda1 - lambda2))
            
            R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
            function code(R, lambda1, lambda2, phi1, phi2)
            	return Float64(R * hypot(Float64(phi1 - phi2), Float64(lambda1 - lambda2)))
            end
            
            R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
            function tmp = code(R, lambda1, lambda2, phi1, phi2)
            	tmp = R * hypot((phi1 - phi2), (lambda1 - lambda2));
            end
            
            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[Sqrt[N[(phi1 - phi2), $MachinePrecision] ^ 2 + N[(lambda1 - lambda2), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
            \\
            R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \lambda_2\right)
            \end{array}
            
            Derivation
            1. Initial program 55.2%

              \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-sqrt.f64N/A

                \[\leadsto R \cdot \color{blue}{\sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
              2. lift-+.f64N/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)}} \]
              3. +-commutativeN/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
              4. lift-*.f64N/A

                \[\leadsto R \cdot \sqrt{\color{blue}{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} + \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \]
              5. lift-*.f64N/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}} \]
              6. pow2N/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}^{2}}} \]
              7. pow-to-expN/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot 2}}} \]
              8. exp-lft-sqrN/A

                \[\leadsto R \cdot \sqrt{\left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right) + \color{blue}{e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)} \cdot e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}}} \]
              9. lower-hypot.f64N/A

                \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right)}\right)} \]
            4. Applied rewrites50.6%

              \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\phi_1 - \phi_2, e^{\log \left(\cos \left(\left(\phi_2 + \phi_1\right) \cdot -0.5\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)} \]
            5. Taylor expanded in phi2 around 0

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right) + \cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}\right) \]
            6. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right) + \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
              2. lower-fma.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)}\right) \]
              3. lower-cos.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\color{blue}{\cos \left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              4. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)}, \lambda_1 - \lambda_2, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              5. lower--.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \color{blue}{\lambda_1 - \lambda_2}, \frac{1}{2} \cdot \left(\phi_2 \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right)\right) \]
              6. associate-*r*N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              7. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              8. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \color{blue}{\left(\frac{1}{2} \cdot \phi_2\right)} \cdot \left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              9. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \color{blue}{\left(\sin \left(\frac{-1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)}\right)\right) \]
              10. lower-sin.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\color{blue}{\sin \left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              11. lower-*.f64N/A

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(\frac{-1}{2} \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(\frac{1}{2} \cdot \phi_2\right) \cdot \left(\sin \color{blue}{\left(\frac{-1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)\right) \]
              12. lower--.f6478.7

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}\right)\right)\right) \]
            7. Applied rewrites78.7%

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \color{blue}{\mathsf{fma}\left(\cos \left(-0.5 \cdot \phi_1\right), \lambda_1 - \lambda_2, \left(0.5 \cdot \phi_2\right) \cdot \left(\sin \left(-0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)\right)}\right) \]
            8. Taylor expanded in phi1 around 0

              \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
            9. Step-by-step derivation
              1. Applied rewrites83.2%

                \[\leadsto R \cdot \mathsf{hypot}\left(\phi_1 - \phi_2, \lambda_1 - \color{blue}{\lambda_2}\right) \]
              2. Add Preprocessing

              Alternative 7: 58.8% accurate, 8.5× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.4 \cdot 10^{+47}:\\ \;\;\;\;\left(-\phi_1\right) \cdot \left(R - R \cdot \frac{\phi_2}{\phi_1}\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\ \end{array} \end{array} \]
              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 -1.4e+47)
                 (* (- phi1) (- R (* R (/ phi2 phi1))))
                 (* (fma R (/ (- phi1) phi2) R) 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 <= -1.4e+47) {
              		tmp = -phi1 * (R - (R * (phi2 / phi1)));
              	} else {
              		tmp = fma(R, (-phi1 / phi2), R) * phi2;
              	}
              	return tmp;
              }
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -1.4e+47)
              		tmp = Float64(Float64(-phi1) * Float64(R - Float64(R * Float64(phi2 / phi1))));
              	else
              		tmp = Float64(fma(R, Float64(Float64(-phi1) / phi2), R) * phi2);
              	end
              	return tmp
              end
              
              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, -1.4e+47], N[((-phi1) * N[(R - N[(R * N[(phi2 / phi1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(R * N[((-phi1) / phi2), $MachinePrecision] + R), $MachinePrecision] * phi2), $MachinePrecision]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -1.4 \cdot 10^{+47}:\\
              \;\;\;\;\left(-\phi_1\right) \cdot \left(R - R \cdot \frac{\phi_2}{\phi_1}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -1.39999999999999994e47

                1. Initial program 42.9%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around -inf

                  \[\leadsto \color{blue}{-1 \cdot \left(\phi_1 \cdot \left(R + -1 \cdot \frac{R \cdot \phi_2}{\phi_1}\right)\right)} \]
                4. Step-by-step derivation
                  1. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(-1 \cdot \phi_1\right) \cdot \left(R + -1 \cdot \frac{R \cdot \phi_2}{\phi_1}\right)} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(-1 \cdot \phi_1\right) \cdot \left(R + -1 \cdot \frac{R \cdot \phi_2}{\phi_1}\right)} \]
                  3. mul-1-negN/A

                    \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \cdot \left(R + -1 \cdot \frac{R \cdot \phi_2}{\phi_1}\right) \]
                  4. lower-neg.f64N/A

                    \[\leadsto \color{blue}{\left(-\phi_1\right)} \cdot \left(R + -1 \cdot \frac{R \cdot \phi_2}{\phi_1}\right) \]
                  5. mul-1-negN/A

                    \[\leadsto \left(-\phi_1\right) \cdot \left(R + \color{blue}{\left(\mathsf{neg}\left(\frac{R \cdot \phi_2}{\phi_1}\right)\right)}\right) \]
                  6. unsub-negN/A

                    \[\leadsto \left(-\phi_1\right) \cdot \color{blue}{\left(R - \frac{R \cdot \phi_2}{\phi_1}\right)} \]
                  7. lower--.f64N/A

                    \[\leadsto \left(-\phi_1\right) \cdot \color{blue}{\left(R - \frac{R \cdot \phi_2}{\phi_1}\right)} \]
                  8. associate-/l*N/A

                    \[\leadsto \left(-\phi_1\right) \cdot \left(R - \color{blue}{R \cdot \frac{\phi_2}{\phi_1}}\right) \]
                  9. lower-*.f64N/A

                    \[\leadsto \left(-\phi_1\right) \cdot \left(R - \color{blue}{R \cdot \frac{\phi_2}{\phi_1}}\right) \]
                  10. lower-/.f6463.6

                    \[\leadsto \left(-\phi_1\right) \cdot \left(R - R \cdot \color{blue}{\frac{\phi_2}{\phi_1}}\right) \]
                5. Applied rewrites63.6%

                  \[\leadsto \color{blue}{\left(-\phi_1\right) \cdot \left(R - R \cdot \frac{\phi_2}{\phi_1}\right)} \]

                if -1.39999999999999994e47 < phi1

                1. Initial program 58.6%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around inf

                  \[\leadsto \color{blue}{\phi_2 \cdot \left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right)} \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  3. +-commutativeN/A

                    \[\leadsto \color{blue}{\left(-1 \cdot \frac{R \cdot \phi_1}{\phi_2} + R\right)} \cdot \phi_2 \]
                  4. mul-1-negN/A

                    \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{R \cdot \phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  5. associate-/l*N/A

                    \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{R \cdot \frac{\phi_1}{\phi_2}}\right)\right) + R\right) \cdot \phi_2 \]
                  6. distribute-rgt-neg-inN/A

                    \[\leadsto \left(\color{blue}{R \cdot \left(\mathsf{neg}\left(\frac{\phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  7. mul-1-negN/A

                    \[\leadsto \left(R \cdot \color{blue}{\left(-1 \cdot \frac{\phi_1}{\phi_2}\right)} + R\right) \cdot \phi_2 \]
                  8. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(R, -1 \cdot \frac{\phi_1}{\phi_2}, R\right)} \cdot \phi_2 \]
                  9. associate-*r/N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  10. lower-/.f64N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  11. mul-1-negN/A

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{\mathsf{neg}\left(\phi_1\right)}}{\phi_2}, R\right) \cdot \phi_2 \]
                  12. lower-neg.f6421.1

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{-\phi_1}}{\phi_2}, R\right) \cdot \phi_2 \]
                5. Applied rewrites21.1%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 8: 58.8% accurate, 9.0× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.4 \cdot 10^{+47}:\\ \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\ \end{array} \end{array} \]
              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 -1.4e+47)
                 (* R (* phi1 (+ -1.0 (/ phi2 phi1))))
                 (* (fma R (/ (- phi1) phi2) R) 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 <= -1.4e+47) {
              		tmp = R * (phi1 * (-1.0 + (phi2 / phi1)));
              	} else {
              		tmp = fma(R, (-phi1 / phi2), R) * phi2;
              	}
              	return tmp;
              }
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -1.4e+47)
              		tmp = Float64(R * Float64(phi1 * Float64(-1.0 + Float64(phi2 / phi1))));
              	else
              		tmp = Float64(fma(R, Float64(Float64(-phi1) / phi2), R) * phi2);
              	end
              	return tmp
              end
              
              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, -1.4e+47], N[(R * N[(phi1 * N[(-1.0 + N[(phi2 / phi1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(R * N[((-phi1) / phi2), $MachinePrecision] + R), $MachinePrecision] * phi2), $MachinePrecision]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -1.4 \cdot 10^{+47}:\\
              \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -1.39999999999999994e47

                1. Initial program 42.9%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around -inf

                  \[\leadsto R \cdot \color{blue}{\left(-1 \cdot \left(\phi_1 \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)\right)} \]
                4. Step-by-step derivation
                  1. associate-*r*N/A

                    \[\leadsto R \cdot \color{blue}{\left(\left(-1 \cdot \phi_1\right) \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)} \]
                  2. lower-*.f64N/A

                    \[\leadsto R \cdot \color{blue}{\left(\left(-1 \cdot \phi_1\right) \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right)} \]
                  3. mul-1-negN/A

                    \[\leadsto R \cdot \left(\color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right) \]
                  4. lower-neg.f64N/A

                    \[\leadsto R \cdot \left(\color{blue}{\left(-\phi_1\right)} \cdot \left(1 + -1 \cdot \frac{\phi_2}{\phi_1}\right)\right) \]
                  5. mul-1-negN/A

                    \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \left(1 + \color{blue}{\left(\mathsf{neg}\left(\frac{\phi_2}{\phi_1}\right)\right)}\right)\right) \]
                  6. unsub-negN/A

                    \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \color{blue}{\left(1 - \frac{\phi_2}{\phi_1}\right)}\right) \]
                  7. lower--.f64N/A

                    \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \color{blue}{\left(1 - \frac{\phi_2}{\phi_1}\right)}\right) \]
                  8. lower-/.f6463.7

                    \[\leadsto R \cdot \left(\left(-\phi_1\right) \cdot \left(1 - \color{blue}{\frac{\phi_2}{\phi_1}}\right)\right) \]
                5. Applied rewrites63.7%

                  \[\leadsto R \cdot \color{blue}{\left(\left(-\phi_1\right) \cdot \left(1 - \frac{\phi_2}{\phi_1}\right)\right)} \]

                if -1.39999999999999994e47 < phi1

                1. Initial program 58.6%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around inf

                  \[\leadsto \color{blue}{\phi_2 \cdot \left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right)} \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  3. +-commutativeN/A

                    \[\leadsto \color{blue}{\left(-1 \cdot \frac{R \cdot \phi_1}{\phi_2} + R\right)} \cdot \phi_2 \]
                  4. mul-1-negN/A

                    \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{R \cdot \phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  5. associate-/l*N/A

                    \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{R \cdot \frac{\phi_1}{\phi_2}}\right)\right) + R\right) \cdot \phi_2 \]
                  6. distribute-rgt-neg-inN/A

                    \[\leadsto \left(\color{blue}{R \cdot \left(\mathsf{neg}\left(\frac{\phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  7. mul-1-negN/A

                    \[\leadsto \left(R \cdot \color{blue}{\left(-1 \cdot \frac{\phi_1}{\phi_2}\right)} + R\right) \cdot \phi_2 \]
                  8. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(R, -1 \cdot \frac{\phi_1}{\phi_2}, R\right)} \cdot \phi_2 \]
                  9. associate-*r/N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  10. lower-/.f64N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  11. mul-1-negN/A

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{\mathsf{neg}\left(\phi_1\right)}}{\phi_2}, R\right) \cdot \phi_2 \]
                  12. lower-neg.f6421.1

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{-\phi_1}}{\phi_2}, R\right) \cdot \phi_2 \]
                5. Applied rewrites21.1%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2} \]
              3. Recombined 2 regimes into one program.
              4. Final simplification30.2%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1.4 \cdot 10^{+47}:\\ \;\;\;\;R \cdot \left(\phi_1 \cdot \left(-1 + \frac{\phi_2}{\phi_1}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\ \end{array} \]
              5. Add Preprocessing

              Alternative 9: 56.8% accurate, 9.0× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -2.5 \cdot 10^{+187}:\\ \;\;\;\;R \cdot \left(-\phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\ \end{array} \end{array} \]
              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 -2.5e+187) (* R (- phi1)) (* (fma R (/ (- phi1) phi2) R) 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 <= -2.5e+187) {
              		tmp = R * -phi1;
              	} else {
              		tmp = fma(R, (-phi1 / phi2), R) * phi2;
              	}
              	return tmp;
              }
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -2.5e+187)
              		tmp = Float64(R * Float64(-phi1));
              	else
              		tmp = Float64(fma(R, Float64(Float64(-phi1) / phi2), R) * phi2);
              	end
              	return tmp
              end
              
              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, -2.5e+187], N[(R * (-phi1)), $MachinePrecision], N[(N[(R * N[((-phi1) / phi2), $MachinePrecision] + R), $MachinePrecision] * phi2), $MachinePrecision]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -2.5 \cdot 10^{+187}:\\
              \;\;\;\;R \cdot \left(-\phi_1\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -2.5000000000000001e187

                1. Initial program 39.5%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around -inf

                  \[\leadsto R \cdot \color{blue}{\left(-1 \cdot \phi_1\right)} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto R \cdot \color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \]
                  2. lower-neg.f6489.0

                    \[\leadsto R \cdot \color{blue}{\left(-\phi_1\right)} \]
                5. Applied rewrites89.0%

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

                if -2.5000000000000001e187 < phi1

                1. Initial program 56.9%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around inf

                  \[\leadsto \color{blue}{\phi_2 \cdot \left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right)} \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  3. +-commutativeN/A

                    \[\leadsto \color{blue}{\left(-1 \cdot \frac{R \cdot \phi_1}{\phi_2} + R\right)} \cdot \phi_2 \]
                  4. mul-1-negN/A

                    \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{R \cdot \phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  5. associate-/l*N/A

                    \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{R \cdot \frac{\phi_1}{\phi_2}}\right)\right) + R\right) \cdot \phi_2 \]
                  6. distribute-rgt-neg-inN/A

                    \[\leadsto \left(\color{blue}{R \cdot \left(\mathsf{neg}\left(\frac{\phi_1}{\phi_2}\right)\right)} + R\right) \cdot \phi_2 \]
                  7. mul-1-negN/A

                    \[\leadsto \left(R \cdot \color{blue}{\left(-1 \cdot \frac{\phi_1}{\phi_2}\right)} + R\right) \cdot \phi_2 \]
                  8. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(R, -1 \cdot \frac{\phi_1}{\phi_2}, R\right)} \cdot \phi_2 \]
                  9. associate-*r/N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  10. lower-/.f64N/A

                    \[\leadsto \mathsf{fma}\left(R, \color{blue}{\frac{-1 \cdot \phi_1}{\phi_2}}, R\right) \cdot \phi_2 \]
                  11. mul-1-negN/A

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{\mathsf{neg}\left(\phi_1\right)}}{\phi_2}, R\right) \cdot \phi_2 \]
                  12. lower-neg.f6423.1

                    \[\leadsto \mathsf{fma}\left(R, \frac{\color{blue}{-\phi_1}}{\phi_2}, R\right) \cdot \phi_2 \]
                5. Applied rewrites23.1%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(R, \frac{-\phi_1}{\phi_2}, R\right) \cdot \phi_2} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 10: 56.8% accurate, 9.0× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -1 \cdot 10^{+204}:\\ \;\;\;\;R \cdot \left(-\phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;\left(R - \frac{\phi_1 \cdot R}{\phi_2}\right) \cdot \phi_2\\ \end{array} \end{array} \]
              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 -1e+204) (* R (- phi1)) (* (- R (/ (* phi1 R) phi2)) 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 <= -1e+204) {
              		tmp = R * -phi1;
              	} else {
              		tmp = (R - ((phi1 * R) / phi2)) * phi2;
              	}
              	return tmp;
              }
              
              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 <= (-1d+204)) then
                      tmp = r * -phi1
                  else
                      tmp = (r - ((phi1 * r) / phi2)) * phi2
                  end if
                  code = tmp
              end function
              
              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 <= -1e+204) {
              		tmp = R * -phi1;
              	} else {
              		tmp = (R - ((phi1 * R) / phi2)) * phi2;
              	}
              	return tmp;
              }
              
              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
              def code(R, lambda1, lambda2, phi1, phi2):
              	tmp = 0
              	if phi1 <= -1e+204:
              		tmp = R * -phi1
              	else:
              		tmp = (R - ((phi1 * R) / phi2)) * phi2
              	return tmp
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -1e+204)
              		tmp = Float64(R * Float64(-phi1));
              	else
              		tmp = Float64(Float64(R - Float64(Float64(phi1 * R) / phi2)) * phi2);
              	end
              	return tmp
              end
              
              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 <= -1e+204)
              		tmp = R * -phi1;
              	else
              		tmp = (R - ((phi1 * R) / phi2)) * phi2;
              	end
              	tmp_2 = tmp;
              end
              
              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, -1e+204], N[(R * (-phi1)), $MachinePrecision], N[(N[(R - N[(N[(phi1 * R), $MachinePrecision] / phi2), $MachinePrecision]), $MachinePrecision] * phi2), $MachinePrecision]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -1 \cdot 10^{+204}:\\
              \;\;\;\;R \cdot \left(-\phi_1\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(R - \frac{\phi_1 \cdot R}{\phi_2}\right) \cdot \phi_2\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -9.99999999999999989e203

                1. Initial program 39.5%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around -inf

                  \[\leadsto R \cdot \color{blue}{\left(-1 \cdot \phi_1\right)} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto R \cdot \color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \]
                  2. lower-neg.f6489.0

                    \[\leadsto R \cdot \color{blue}{\left(-\phi_1\right)} \]
                5. Applied rewrites89.0%

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

                if -9.99999999999999989e203 < phi1

                1. Initial program 56.9%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around 0

                  \[\leadsto R \cdot \color{blue}{\sqrt{{\cos \left(\frac{1}{2} \cdot \phi_1\right)}^{2} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}}} \]
                4. Step-by-step derivation
                  1. unpow2N/A

                    \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right)} \cdot {\left(\lambda_1 - \lambda_2\right)}^{2} + {\phi_1}^{2}} \]
                  2. unpow2N/A

                    \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \cos \left(\frac{1}{2} \cdot \phi_1\right)\right) \cdot \color{blue}{\left(\left(\lambda_1 - \lambda_2\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
                  3. unswap-sqrN/A

                    \[\leadsto R \cdot \sqrt{\color{blue}{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right)} + {\phi_1}^{2}} \]
                  4. unpow2N/A

                    \[\leadsto R \cdot \sqrt{\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) \cdot \left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)\right) + \color{blue}{\phi_1 \cdot \phi_1}} \]
                  5. lower-hypot.f64N/A

                    \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]
                  6. lower-*.f64N/A

                    \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
                  7. lower-cos.f64N/A

                    \[\leadsto R \cdot \mathsf{hypot}\left(\color{blue}{\cos \left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
                  8. lower-*.f64N/A

                    \[\leadsto R \cdot \mathsf{hypot}\left(\cos \color{blue}{\left(\frac{1}{2} \cdot \phi_1\right)} \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right) \]
                  9. lower--.f6466.2

                    \[\leadsto R \cdot \mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \color{blue}{\left(\lambda_1 - \lambda_2\right)}, \phi_1\right) \]
                5. Applied rewrites66.2%

                  \[\leadsto R \cdot \color{blue}{\mathsf{hypot}\left(\cos \left(0.5 \cdot \phi_1\right) \cdot \left(\lambda_1 - \lambda_2\right), \phi_1\right)} \]
                6. Taylor expanded in phi2 around inf

                  \[\leadsto \color{blue}{\phi_2 \cdot \left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right)} \]
                7. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(R + -1 \cdot \frac{R \cdot \phi_1}{\phi_2}\right) \cdot \phi_2} \]
                  3. mul-1-negN/A

                    \[\leadsto \left(R + \color{blue}{\left(\mathsf{neg}\left(\frac{R \cdot \phi_1}{\phi_2}\right)\right)}\right) \cdot \phi_2 \]
                  4. unsub-negN/A

                    \[\leadsto \color{blue}{\left(R - \frac{R \cdot \phi_1}{\phi_2}\right)} \cdot \phi_2 \]
                  5. lower--.f64N/A

                    \[\leadsto \color{blue}{\left(R - \frac{R \cdot \phi_1}{\phi_2}\right)} \cdot \phi_2 \]
                  6. lower-/.f64N/A

                    \[\leadsto \left(R - \color{blue}{\frac{R \cdot \phi_1}{\phi_2}}\right) \cdot \phi_2 \]
                  7. *-commutativeN/A

                    \[\leadsto \left(R - \frac{\color{blue}{\phi_1 \cdot R}}{\phi_2}\right) \cdot \phi_2 \]
                  8. lower-*.f6423.6

                    \[\leadsto \left(R - \frac{\color{blue}{\phi_1 \cdot R}}{\phi_2}\right) \cdot \phi_2 \]
                8. Applied rewrites23.6%

                  \[\leadsto \color{blue}{\left(R - \frac{\phi_1 \cdot R}{\phi_2}\right) \cdot \phi_2} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 11: 52.3% accurate, 19.9× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ \begin{array}{l} \mathbf{if}\;\phi_1 \leq -4.2 \cdot 10^{+41}:\\ \;\;\;\;R \cdot \left(-\phi_1\right)\\ \mathbf{else}:\\ \;\;\;\;R \cdot \phi_2\\ \end{array} \end{array} \]
              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 -4.2e+41) (* R (- phi1)) (* R 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 <= -4.2e+41) {
              		tmp = R * -phi1;
              	} else {
              		tmp = R * phi2;
              	}
              	return tmp;
              }
              
              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 <= (-4.2d+41)) then
                      tmp = r * -phi1
                  else
                      tmp = r * phi2
                  end if
                  code = tmp
              end function
              
              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 <= -4.2e+41) {
              		tmp = R * -phi1;
              	} else {
              		tmp = R * phi2;
              	}
              	return tmp;
              }
              
              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
              def code(R, lambda1, lambda2, phi1, phi2):
              	tmp = 0
              	if phi1 <= -4.2e+41:
              		tmp = R * -phi1
              	else:
              		tmp = R * phi2
              	return tmp
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	tmp = 0.0
              	if (phi1 <= -4.2e+41)
              		tmp = Float64(R * Float64(-phi1));
              	else
              		tmp = Float64(R * phi2);
              	end
              	return tmp
              end
              
              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 <= -4.2e+41)
              		tmp = R * -phi1;
              	else
              		tmp = R * phi2;
              	end
              	tmp_2 = tmp;
              end
              
              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, -4.2e+41], N[(R * (-phi1)), $MachinePrecision], N[(R * phi2), $MachinePrecision]]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;\phi_1 \leq -4.2 \cdot 10^{+41}:\\
              \;\;\;\;R \cdot \left(-\phi_1\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;R \cdot \phi_2\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if phi1 < -4.1999999999999999e41

                1. Initial program 42.9%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around -inf

                  \[\leadsto R \cdot \color{blue}{\left(-1 \cdot \phi_1\right)} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto R \cdot \color{blue}{\left(\mathsf{neg}\left(\phi_1\right)\right)} \]
                  2. lower-neg.f6460.9

                    \[\leadsto R \cdot \color{blue}{\left(-\phi_1\right)} \]
                5. Applied rewrites60.9%

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

                if -4.1999999999999999e41 < phi1

                1. Initial program 58.6%

                  \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi2 around inf

                  \[\leadsto \color{blue}{R \cdot \phi_2} \]
                4. Step-by-step derivation
                  1. lower-*.f6419.9

                    \[\leadsto \color{blue}{R \cdot \phi_2} \]
                5. Applied rewrites19.9%

                  \[\leadsto \color{blue}{R \cdot \phi_2} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 12: 31.7% accurate, 46.5× speedup?

              \[\begin{array}{l} [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\ \\ R \cdot \phi_2 \end{array} \]
              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 phi2))
              assert(R < lambda1 && lambda1 < lambda2 && lambda2 < phi1 && phi1 < phi2);
              double code(double R, double lambda1, double lambda2, double phi1, double phi2) {
              	return R * phi2;
              }
              
              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 * phi2
              end function
              
              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 * phi2;
              }
              
              [R, lambda1, lambda2, phi1, phi2] = sort([R, lambda1, lambda2, phi1, phi2])
              def code(R, lambda1, lambda2, phi1, phi2):
              	return R * phi2
              
              R, lambda1, lambda2, phi1, phi2 = sort([R, lambda1, lambda2, phi1, phi2])
              function code(R, lambda1, lambda2, phi1, phi2)
              	return Float64(R * phi2)
              end
              
              R, lambda1, lambda2, phi1, phi2 = num2cell(sort([R, lambda1, lambda2, phi1, phi2])){:}
              function tmp = code(R, lambda1, lambda2, phi1, phi2)
              	tmp = R * phi2;
              end
              
              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 * phi2), $MachinePrecision]
              
              \begin{array}{l}
              [R, lambda1, lambda2, phi1, phi2] = \mathsf{sort}([R, lambda1, lambda2, phi1, phi2])\\
              \\
              R \cdot \phi_2
              \end{array}
              
              Derivation
              1. Initial program 55.2%

                \[R \cdot \sqrt{\left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) \cdot \left(\left(\lambda_1 - \lambda_2\right) \cdot \cos \left(\frac{\phi_1 + \phi_2}{2}\right)\right) + \left(\phi_1 - \phi_2\right) \cdot \left(\phi_1 - \phi_2\right)} \]
              2. Add Preprocessing
              3. Taylor expanded in phi2 around inf

                \[\leadsto \color{blue}{R \cdot \phi_2} \]
              4. Step-by-step derivation
                1. lower-*.f6417.5

                  \[\leadsto \color{blue}{R \cdot \phi_2} \]
              5. Applied rewrites17.5%

                \[\leadsto \color{blue}{R \cdot \phi_2} \]
              6. Add Preprocessing

              Reproduce

              ?
              herbie shell --seed 2024309 
              (FPCore (R lambda1 lambda2 phi1 phi2)
                :name "Equirectangular approximation to distance on a great circle"
                :precision binary64
                (* R (sqrt (+ (* (* (- lambda1 lambda2) (cos (/ (+ phi1 phi2) 2.0))) (* (- lambda1 lambda2) (cos (/ (+ phi1 phi2) 2.0)))) (* (- phi1 phi2) (- phi1 phi2))))))