Destination given bearing on a great circle

Percentage Accurate: 99.8% → 99.9%
Time: 16.9s
Alternatives: 16
Speedup: 1.2×

Specification

?
\[\begin{array}{l} \\ \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  lambda1
  (atan2
   (* (* (sin theta) (sin delta)) (cos phi1))
   (-
    (cos delta)
    (*
     (sin phi1)
     (sin
      (asin
       (+
        (* (sin phi1) (cos delta))
        (* (* (cos phi1) (sin delta)) (cos theta))))))))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))));
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))))
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return lambda1 + Math.atan2(((Math.sin(theta) * Math.sin(delta)) * Math.cos(phi1)), (Math.cos(delta) - (Math.sin(phi1) * Math.sin(Math.asin(((Math.sin(phi1) * Math.cos(delta)) + ((Math.cos(phi1) * Math.sin(delta)) * Math.cos(theta))))))));
}
def code(lambda1, phi1, phi2, delta, theta):
	return lambda1 + math.atan2(((math.sin(theta) * math.sin(delta)) * math.cos(phi1)), (math.cos(delta) - (math.sin(phi1) * math.sin(math.asin(((math.sin(phi1) * math.cos(delta)) + ((math.cos(phi1) * math.sin(delta)) * math.cos(theta))))))))
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(lambda1 + atan(Float64(Float64(sin(theta) * sin(delta)) * cos(phi1)), Float64(cos(delta) - Float64(sin(phi1) * sin(asin(Float64(Float64(sin(phi1) * cos(delta)) + Float64(Float64(cos(phi1) * sin(delta)) * cos(theta)))))))))
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))));
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(lambda1 + N[ArcTan[N[(N[(N[Sin[theta], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Cos[phi1], $MachinePrecision]), $MachinePrecision] / N[(N[Cos[delta], $MachinePrecision] - N[(N[Sin[phi1], $MachinePrecision] * N[Sin[N[ArcSin[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Cos[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}
\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 16 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: 99.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  lambda1
  (atan2
   (* (* (sin theta) (sin delta)) (cos phi1))
   (-
    (cos delta)
    (*
     (sin phi1)
     (sin
      (asin
       (+
        (* (sin phi1) (cos delta))
        (* (* (cos phi1) (sin delta)) (cos theta))))))))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))));
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))))
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return lambda1 + Math.atan2(((Math.sin(theta) * Math.sin(delta)) * Math.cos(phi1)), (Math.cos(delta) - (Math.sin(phi1) * Math.sin(Math.asin(((Math.sin(phi1) * Math.cos(delta)) + ((Math.cos(phi1) * Math.sin(delta)) * Math.cos(theta))))))));
}
def code(lambda1, phi1, phi2, delta, theta):
	return lambda1 + math.atan2(((math.sin(theta) * math.sin(delta)) * math.cos(phi1)), (math.cos(delta) - (math.sin(phi1) * math.sin(math.asin(((math.sin(phi1) * math.cos(delta)) + ((math.cos(phi1) * math.sin(delta)) * math.cos(theta))))))))
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(lambda1 + atan(Float64(Float64(sin(theta) * sin(delta)) * cos(phi1)), Float64(cos(delta) - Float64(sin(phi1) * sin(asin(Float64(Float64(sin(phi1) * cos(delta)) + Float64(Float64(cos(phi1) * sin(delta)) * cos(theta)))))))))
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = lambda1 + atan2(((sin(theta) * sin(delta)) * cos(phi1)), (cos(delta) - (sin(phi1) * sin(asin(((sin(phi1) * cos(delta)) + ((cos(phi1) * sin(delta)) * cos(theta))))))));
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(lambda1 + N[ArcTan[N[(N[(N[Sin[theta], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Cos[phi1], $MachinePrecision]), $MachinePrecision] / N[(N[Cos[delta], $MachinePrecision] - N[(N[Sin[phi1], $MachinePrecision] * N[Sin[N[ArcSin[N[(N[(N[Sin[phi1], $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Cos[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}
\end{array}

Alternative 1: 99.9% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \cos delta \cdot {\cos \phi_1}^{2}\right)} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (cos phi1) (* (sin delta) (sin theta)))
   (fma
    (* (* (cos theta) (sin delta)) (- (cos phi1)))
    (sin phi1)
    (* (cos delta) (pow (cos phi1) 2.0))))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2((cos(phi1) * (sin(delta) * sin(theta))), fma(((cos(theta) * sin(delta)) * -cos(phi1)), sin(phi1), (cos(delta) * pow(cos(phi1), 2.0)))) + lambda1;
}
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(cos(phi1) * Float64(sin(delta) * sin(theta))), fma(Float64(Float64(cos(theta) * sin(delta)) * Float64(-cos(phi1))), sin(phi1), Float64(cos(delta) * (cos(phi1) ^ 2.0)))) + lambda1)
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[(N[Cos[theta], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * (-N[Cos[phi1], $MachinePrecision])), $MachinePrecision] * N[Sin[phi1], $MachinePrecision] + N[(N[Cos[delta], $MachinePrecision] * N[Power[N[Cos[phi1], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \cos delta \cdot {\cos \phi_1}^{2}\right)} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    3. lift-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    4. lift-asin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    5. sin-asinN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    6. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    7. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
    8. distribute-rgt-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
    9. associate--r+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
  4. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
  5. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)}} \]
  6. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{\left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right)} \cdot \cos delta\right)} \]
    2. lift-neg.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\color{blue}{\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right)} + 1\right) \cdot \cos delta\right)} \]
    3. lift-fma.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\color{blue}{\left(\frac{-1}{2} \cdot \cos \left(\phi_1 + \phi_1\right) + \frac{1}{2}\right)}\right)\right) + 1\right) \cdot \cos delta\right)} \]
    4. distribute-neg-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{-1}{2} \cdot \cos \left(\phi_1 + \phi_1\right)\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} + 1\right) \cdot \cos delta\right)} \]
    5. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\left(\mathsf{neg}\left(\frac{-1}{2} \cdot \cos \color{blue}{\left(\phi_1 + \phi_1\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    6. count-2N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\left(\mathsf{neg}\left(\frac{-1}{2} \cdot \cos \color{blue}{\left(2 \cdot \phi_1\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    7. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\left(\mathsf{neg}\left(\frac{-1}{2} \cdot \cos \color{blue}{\left(2 \cdot \phi_1\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    8. distribute-lft-neg-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right) \cdot \cos \left(2 \cdot \phi_1\right)} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    9. metadata-evalN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\color{blue}{\frac{1}{2}} \cdot \cos \left(2 \cdot \phi_1\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    10. lift-cos.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot \phi_1\right)} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot \phi_1\right)} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    12. metadata-evalN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right) + \color{blue}{\frac{-1}{2}}\right) + 1\right) \cdot \cos delta\right)} \]
    13. associate-+l+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{\left(\frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right) + \left(\frac{-1}{2} + 1\right)\right)} \cdot \cos delta\right)} \]
    14. metadata-evalN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right) + \color{blue}{\frac{1}{2}}\right) \cdot \cos delta\right)} \]
    15. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right)} \cdot \cos delta\right)} \]
    16. sqr-cos-aN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{\left(\cos \phi_1 \cdot \cos \phi_1\right)} \cdot \cos delta\right)} \]
    17. lift-cos.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\color{blue}{\cos \phi_1} \cdot \cos \phi_1\right) \cdot \cos delta\right)} \]
    18. lift-cos.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\cos \phi_1 \cdot \color{blue}{\cos \phi_1}\right) \cdot \cos delta\right)} \]
    19. pow2N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{{\cos \phi_1}^{2}} \cdot \cos delta\right)} \]
    20. lower-pow.f6499.8

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{{\cos \phi_1}^{2}} \cdot \cos delta\right)} \]
  7. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \color{blue}{{\cos \phi_1}^{2}} \cdot \cos delta\right)} \]
  8. Final simplification99.8%

    \[\leadsto \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \cos delta \cdot {\cos \phi_1}^{2}\right)} + \lambda_1 \]
  9. Add Preprocessing

Alternative 2: 99.7% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (cos phi1) (* (sin delta) (sin theta)))
   (fma
    (* (* (cos theta) (sin delta)) (- (cos phi1)))
    (sin phi1)
    (* (- 1.0 (fma -0.5 (cos (+ phi1 phi1)) 0.5)) (cos delta))))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2((cos(phi1) * (sin(delta) * sin(theta))), fma(((cos(theta) * sin(delta)) * -cos(phi1)), sin(phi1), ((1.0 - fma(-0.5, cos((phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1;
}
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(cos(phi1) * Float64(sin(delta) * sin(theta))), fma(Float64(Float64(cos(theta) * sin(delta)) * Float64(-cos(phi1))), sin(phi1), Float64(Float64(1.0 - fma(-0.5, cos(Float64(phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1)
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[(N[Cos[theta], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * (-N[Cos[phi1], $MachinePrecision])), $MachinePrecision] * N[Sin[phi1], $MachinePrecision] + N[(N[(1.0 - N[(-0.5 * N[Cos[N[(phi1 + phi1), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    3. lift-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    4. lift-asin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    5. sin-asinN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    6. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    7. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
    8. distribute-rgt-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
    9. associate--r+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
  4. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
  5. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)}} \]
  6. Final simplification99.8%

    \[\leadsto \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \]
  7. Add Preprocessing

Alternative 3: 99.7% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin theta\right) \cdot \sin delta}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (* (cos phi1) (sin theta)) (sin delta))
   (fma
    (* (* (cos theta) (sin delta)) (- (cos phi1)))
    (sin phi1)
    (* (- 1.0 (fma -0.5 (cos (+ phi1 phi1)) 0.5)) (cos delta))))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2(((cos(phi1) * sin(theta)) * sin(delta)), fma(((cos(theta) * sin(delta)) * -cos(phi1)), sin(phi1), ((1.0 - fma(-0.5, cos((phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1;
}
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(Float64(cos(phi1) * sin(theta)) * sin(delta)), fma(Float64(Float64(cos(theta) * sin(delta)) * Float64(-cos(phi1))), sin(phi1), Float64(Float64(1.0 - fma(-0.5, cos(Float64(phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1)
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] / N[(N[(N[(N[Cos[theta], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * (-N[Cos[phi1], $MachinePrecision])), $MachinePrecision] * N[Sin[phi1], $MachinePrecision] + N[(N[(1.0 - N[(-0.5 * N[Cos[N[(phi1 + phi1), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin theta\right) \cdot \sin delta}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    3. lift-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    4. lift-asin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    5. sin-asinN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    6. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    7. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
    8. distribute-rgt-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
    9. associate--r+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
  4. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
  5. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)}} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    3. associate-*l*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    4. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)}}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    5. associate-*r*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \cos \phi_1\right) \cdot \sin delta}}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    6. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \cos \phi_1\right) \cdot \sin delta}}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\cos \phi_1\right)\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    7. lower-*.f6499.8

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \cos \phi_1\right)} \cdot \sin delta}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)} \]
  7. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \cos \phi_1\right) \cdot \sin delta}}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)} \]
  8. Final simplification99.8%

    \[\leadsto \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin theta\right) \cdot \sin delta}{\mathsf{fma}\left(\left(\cos theta \cdot \sin delta\right) \cdot \left(-\cos \phi_1\right), \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \]
  9. Add Preprocessing

Alternative 4: 94.4% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\left(\cos delta - \left(\sin \phi_1 \cdot \sin delta\right) \cdot \cos \phi_1\right) - \left(0.5 - \cos \left(2 \cdot \phi_1\right) \cdot 0.5\right) \cdot \cos delta} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (cos phi1) (* (sin delta) (sin theta)))
   (-
    (- (cos delta) (* (* (sin phi1) (sin delta)) (cos phi1)))
    (* (- 0.5 (* (cos (* 2.0 phi1)) 0.5)) (cos delta))))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2((cos(phi1) * (sin(delta) * sin(theta))), ((cos(delta) - ((sin(phi1) * sin(delta)) * cos(phi1))) - ((0.5 - (cos((2.0 * phi1)) * 0.5)) * cos(delta)))) + lambda1;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = atan2((cos(phi1) * (sin(delta) * sin(theta))), ((cos(delta) - ((sin(phi1) * sin(delta)) * cos(phi1))) - ((0.5d0 - (cos((2.0d0 * phi1)) * 0.5d0)) * cos(delta)))) + lambda1
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return Math.atan2((Math.cos(phi1) * (Math.sin(delta) * Math.sin(theta))), ((Math.cos(delta) - ((Math.sin(phi1) * Math.sin(delta)) * Math.cos(phi1))) - ((0.5 - (Math.cos((2.0 * phi1)) * 0.5)) * Math.cos(delta)))) + lambda1;
}
def code(lambda1, phi1, phi2, delta, theta):
	return math.atan2((math.cos(phi1) * (math.sin(delta) * math.sin(theta))), ((math.cos(delta) - ((math.sin(phi1) * math.sin(delta)) * math.cos(phi1))) - ((0.5 - (math.cos((2.0 * phi1)) * 0.5)) * math.cos(delta)))) + lambda1
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(cos(phi1) * Float64(sin(delta) * sin(theta))), Float64(Float64(cos(delta) - Float64(Float64(sin(phi1) * sin(delta)) * cos(phi1))) - Float64(Float64(0.5 - Float64(cos(Float64(2.0 * phi1)) * 0.5)) * cos(delta)))) + lambda1)
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = atan2((cos(phi1) * (sin(delta) * sin(theta))), ((cos(delta) - ((sin(phi1) * sin(delta)) * cos(phi1))) - ((0.5 - (cos((2.0 * phi1)) * 0.5)) * cos(delta)))) + lambda1;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[Cos[delta], $MachinePrecision] - N[(N[(N[Sin[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Cos[phi1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(0.5 - N[(N[Cos[N[(2.0 * phi1), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\left(\cos delta - \left(\sin \phi_1 \cdot \sin delta\right) \cdot \cos \phi_1\right) - \left(0.5 - \cos \left(2 \cdot \phi_1\right) \cdot 0.5\right) \cdot \cos delta} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    3. lift-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    4. lift-asin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    5. sin-asinN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    6. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    7. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
    8. distribute-rgt-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
    9. associate--r+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
  4. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
  5. Taylor expanded in theta around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\cos \phi_1 \cdot \left(\sin delta \cdot \sin \phi_1\right)}\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
  6. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\left(\sin delta \cdot \sin \phi_1\right) \cdot \cos \phi_1}\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    2. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\left(\sin delta \cdot \sin \phi_1\right) \cdot \cos \phi_1}\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    3. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\left(\sin \phi_1 \cdot \sin delta\right)} \cdot \cos \phi_1\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    4. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\left(\sin \phi_1 \cdot \sin delta\right)} \cdot \cos \phi_1\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    5. lower-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \left(\color{blue}{\sin \phi_1} \cdot \sin delta\right) \cdot \cos \phi_1\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    6. lower-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \left(\sin \phi_1 \cdot \color{blue}{\sin delta}\right) \cdot \cos \phi_1\right) - \left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
    7. lower-cos.f6495.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \left(\sin \phi_1 \cdot \sin delta\right) \cdot \color{blue}{\cos \phi_1}\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
  7. Applied rewrites95.3%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\left(\cos delta - \color{blue}{\left(\sin \phi_1 \cdot \sin delta\right) \cdot \cos \phi_1}\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta} \]
  8. Final simplification95.3%

    \[\leadsto \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\left(\cos delta - \left(\sin \phi_1 \cdot \sin delta\right) \cdot \cos \phi_1\right) - \left(0.5 - \cos \left(2 \cdot \phi_1\right) \cdot 0.5\right) \cdot \cos delta} + \lambda_1 \]
  9. Add Preprocessing

Alternative 5: 94.4% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(-\sin delta\right) \cdot \cos \phi_1, \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (cos phi1) (* (sin delta) (sin theta)))
   (fma
    (* (- (sin delta)) (cos phi1))
    (sin phi1)
    (* (- 1.0 (fma -0.5 (cos (+ phi1 phi1)) 0.5)) (cos delta))))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2((cos(phi1) * (sin(delta) * sin(theta))), fma((-sin(delta) * cos(phi1)), sin(phi1), ((1.0 - fma(-0.5, cos((phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1;
}
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(cos(phi1) * Float64(sin(delta) * sin(theta))), fma(Float64(Float64(-sin(delta)) * cos(phi1)), sin(phi1), Float64(Float64(1.0 - fma(-0.5, cos(Float64(phi1 + phi1)), 0.5)) * cos(delta)))) + lambda1)
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[((-N[Sin[delta], $MachinePrecision]) * N[Cos[phi1], $MachinePrecision]), $MachinePrecision] * N[Sin[phi1], $MachinePrecision] + N[(N[(1.0 - N[(-0.5 * N[Cos[N[(phi1 + phi1), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision] * N[Cos[delta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(-\sin delta\right) \cdot \cos \phi_1, \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    3. lift-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    4. lift-asin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    5. sin-asinN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    6. lift-+.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
    7. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
    8. distribute-rgt-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
    9. associate--r+N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
  4. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
  5. Applied rewrites99.8%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\left(-\cos \phi_1\right) \cdot \left(\sin delta \cdot \cos theta\right), \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)}} \]
  6. Taylor expanded in theta around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{-1 \cdot \left(\cos \phi_1 \cdot \sin delta\right)}, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
  7. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(\cos \phi_1 \cdot \sin delta\right)}, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    2. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{\sin delta \cdot \cos \phi_1}\right), \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    3. distribute-lft-neg-inN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\left(\mathsf{neg}\left(\sin delta\right)\right) \cdot \cos \phi_1}, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    4. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\left(\mathsf{neg}\left(\sin delta\right)\right) \cdot \cos \phi_1}, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    5. lower-neg.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\left(\mathsf{neg}\left(\sin delta\right)\right)} \cdot \cos \phi_1, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    6. lower-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(\mathsf{neg}\left(\color{blue}{\sin delta}\right)\right) \cdot \cos \phi_1, \sin \phi_1, \left(\left(\mathsf{neg}\left(\mathsf{fma}\left(\frac{-1}{2}, \cos \left(\phi_1 + \phi_1\right), \frac{1}{2}\right)\right)\right) + 1\right) \cdot \cos delta\right)} \]
    7. lower-cos.f6495.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\left(-\sin delta\right) \cdot \color{blue}{\cos \phi_1}, \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)} \]
  8. Applied rewrites95.3%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\left(-\sin delta\right) \cdot \cos \phi_1}, \sin \phi_1, \left(\left(-\mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) + 1\right) \cdot \cos delta\right)} \]
  9. Final simplification95.3%

    \[\leadsto \tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\left(-\sin delta\right) \cdot \cos \phi_1, \sin \phi_1, \left(1 - \mathsf{fma}\left(-0.5, \cos \left(\phi_1 + \phi_1\right), 0.5\right)\right) \cdot \cos delta\right)} + \lambda_1 \]
  10. Add Preprocessing

Alternative 6: 92.1% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - {\sin \phi_1}^{2}} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+
  (atan2
   (* (* (cos phi1) (sin delta)) (sin theta))
   (- (cos delta) (pow (sin phi1) 2.0)))
  lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2(((cos(phi1) * sin(delta)) * sin(theta)), (cos(delta) - pow(sin(phi1), 2.0))) + lambda1;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = atan2(((cos(phi1) * sin(delta)) * sin(theta)), (cos(delta) - (sin(phi1) ** 2.0d0))) + lambda1
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return Math.atan2(((Math.cos(phi1) * Math.sin(delta)) * Math.sin(theta)), (Math.cos(delta) - Math.pow(Math.sin(phi1), 2.0))) + lambda1;
}
def code(lambda1, phi1, phi2, delta, theta):
	return math.atan2(((math.cos(phi1) * math.sin(delta)) * math.sin(theta)), (math.cos(delta) - math.pow(math.sin(phi1), 2.0))) + lambda1
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(Float64(cos(phi1) * sin(delta)) * sin(theta)), Float64(cos(delta) - (sin(phi1) ^ 2.0))) + lambda1)
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = atan2(((cos(phi1) * sin(delta)) * sin(theta)), (cos(delta) - (sin(phi1) ^ 2.0))) + lambda1;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[(N[Cos[delta], $MachinePrecision] - N[Power[N[Sin[phi1], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - {\sin \phi_1}^{2}} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in delta around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(delta \cdot \left(\cos \phi_1 \cdot \left(\cos theta \cdot \sin \phi_1\right)\right) + {\sin \phi_1}^{2}\right)}} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left({\sin \phi_1}^{2} + delta \cdot \left(\cos \phi_1 \cdot \left(\cos theta \cdot \sin \phi_1\right)\right)\right)}} \]
    2. unpow2N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \left(\color{blue}{\sin \phi_1 \cdot \sin \phi_1} + delta \cdot \left(\cos \phi_1 \cdot \left(\cos theta \cdot \sin \phi_1\right)\right)\right)} \]
    3. associate-*r*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \left(\sin \phi_1 \cdot \sin \phi_1 + delta \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \cos theta\right) \cdot \sin \phi_1\right)}\right)} \]
    4. associate-*r*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \left(\sin \phi_1 \cdot \sin \phi_1 + \color{blue}{\left(delta \cdot \left(\cos \phi_1 \cdot \cos theta\right)\right) \cdot \sin \phi_1}\right)} \]
    5. distribute-rgt-outN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \left(\sin \phi_1 + delta \cdot \left(\cos \phi_1 \cdot \cos theta\right)\right)}} \]
    6. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \left(\sin \phi_1 + delta \cdot \left(\cos \phi_1 \cdot \cos theta\right)\right)}} \]
    7. lower-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1} \cdot \left(\sin \phi_1 + delta \cdot \left(\cos \phi_1 \cdot \cos theta\right)\right)} \]
    8. +-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(delta \cdot \left(\cos \phi_1 \cdot \cos theta\right) + \sin \phi_1\right)}} \]
    9. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \left(delta \cdot \color{blue}{\left(\cos theta \cdot \cos \phi_1\right)} + \sin \phi_1\right)} \]
    10. associate-*r*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \left(\color{blue}{\left(delta \cdot \cos theta\right) \cdot \cos \phi_1} + \sin \phi_1\right)} \]
    11. lower-fma.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)}} \]
    12. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(\color{blue}{delta \cdot \cos theta}, \cos \phi_1, \sin \phi_1\right)} \]
    13. lower-cos.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \color{blue}{\cos theta}, \cos \phi_1, \sin \phi_1\right)} \]
    14. lower-cos.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \color{blue}{\cos \phi_1}, \sin \phi_1\right)} \]
    15. lower-sin.f6485.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \color{blue}{\sin \phi_1}\right)} \]
  5. Applied rewrites85.3%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)}} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    3. associate-*l*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    4. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    5. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    6. lower-*.f6485.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    7. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    8. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
    9. lower-*.f6485.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
  7. Applied rewrites85.3%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta - \sin \phi_1 \cdot \mathsf{fma}\left(delta \cdot \cos theta, \cos \phi_1, \sin \phi_1\right)} \]
  8. Taylor expanded in delta around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - \color{blue}{{\sin \phi_1}^{2}}} \]
  9. Step-by-step derivation
    1. lower-pow.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - \color{blue}{{\sin \phi_1}^{2}}} \]
    2. lower-sin.f6492.9

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - {\color{blue}{\sin \phi_1}}^{2}} \]
  10. Applied rewrites92.9%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - \color{blue}{{\sin \phi_1}^{2}}} \]
  11. Final simplification92.9%

    \[\leadsto \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta - {\sin \phi_1}^{2}} + \lambda_1 \]
  12. Add Preprocessing

Alternative 7: 91.2% accurate, 2.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta\\ t_2 := \tan^{-1}_* \frac{t\_1}{\cos delta} + \lambda_1\\ \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{t\_1}{{\cos \phi_1}^{2}} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (let* ((t_1 (* (* (cos phi1) (sin delta)) (sin theta)))
        (t_2 (+ (atan2 t_1 (cos delta)) lambda1)))
   (if (<= delta -2.4e+19)
     t_2
     (if (<= delta 1.9e-9) (+ (atan2 t_1 (pow (cos phi1) 2.0)) lambda1) t_2))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double t_1 = (cos(phi1) * sin(delta)) * sin(theta);
	double t_2 = atan2(t_1, cos(delta)) + lambda1;
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = t_2;
	} else if (delta <= 1.9e-9) {
		tmp = atan2(t_1, pow(cos(phi1), 2.0)) + lambda1;
	} else {
		tmp = t_2;
	}
	return tmp;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: tmp
    t_1 = (cos(phi1) * sin(delta)) * sin(theta)
    t_2 = atan2(t_1, cos(delta)) + lambda1
    if (delta <= (-2.4d+19)) then
        tmp = t_2
    else if (delta <= 1.9d-9) then
        tmp = atan2(t_1, (cos(phi1) ** 2.0d0)) + lambda1
    else
        tmp = t_2
    end if
    code = tmp
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double t_1 = (Math.cos(phi1) * Math.sin(delta)) * Math.sin(theta);
	double t_2 = Math.atan2(t_1, Math.cos(delta)) + lambda1;
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = t_2;
	} else if (delta <= 1.9e-9) {
		tmp = Math.atan2(t_1, Math.pow(Math.cos(phi1), 2.0)) + lambda1;
	} else {
		tmp = t_2;
	}
	return tmp;
}
def code(lambda1, phi1, phi2, delta, theta):
	t_1 = (math.cos(phi1) * math.sin(delta)) * math.sin(theta)
	t_2 = math.atan2(t_1, math.cos(delta)) + lambda1
	tmp = 0
	if delta <= -2.4e+19:
		tmp = t_2
	elif delta <= 1.9e-9:
		tmp = math.atan2(t_1, math.pow(math.cos(phi1), 2.0)) + lambda1
	else:
		tmp = t_2
	return tmp
function code(lambda1, phi1, phi2, delta, theta)
	t_1 = Float64(Float64(cos(phi1) * sin(delta)) * sin(theta))
	t_2 = Float64(atan(t_1, cos(delta)) + lambda1)
	tmp = 0.0
	if (delta <= -2.4e+19)
		tmp = t_2;
	elseif (delta <= 1.9e-9)
		tmp = Float64(atan(t_1, (cos(phi1) ^ 2.0)) + lambda1);
	else
		tmp = t_2;
	end
	return tmp
end
function tmp_2 = code(lambda1, phi1, phi2, delta, theta)
	t_1 = (cos(phi1) * sin(delta)) * sin(theta);
	t_2 = atan2(t_1, cos(delta)) + lambda1;
	tmp = 0.0;
	if (delta <= -2.4e+19)
		tmp = t_2;
	elseif (delta <= 1.9e-9)
		tmp = atan2(t_1, (cos(phi1) ^ 2.0)) + lambda1;
	else
		tmp = t_2;
	end
	tmp_2 = tmp;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := Block[{t$95$1 = N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[ArcTan[t$95$1 / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]}, If[LessEqual[delta, -2.4e+19], t$95$2, If[LessEqual[delta, 1.9e-9], N[(N[ArcTan[t$95$1 / N[Power[N[Cos[phi1], $MachinePrecision], 2.0], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], t$95$2]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta\\
t_2 := \tan^{-1}_* \frac{t\_1}{\cos delta} + \lambda_1\\
\mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\
\;\;\;\;\tan^{-1}_* \frac{t\_1}{{\cos \phi_1}^{2}} + \lambda_1\\

\mathbf{else}:\\
\;\;\;\;t\_2\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if delta < -2.4e19 or 1.90000000000000006e-9 < delta

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    4. Step-by-step derivation
      1. lower-cos.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    5. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta} \]
      2. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta} \]
      3. associate-*l*N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      4. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      5. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      6. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      7. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta} \]
      8. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
      9. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
    7. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta} \]

    if -2.4e19 < delta < 1.90000000000000006e-9

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    4. Step-by-step derivation
      1. lower-cos.f6490.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    5. Applied rewrites90.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta} \]
      2. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta} \]
      3. associate-*l*N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      4. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      5. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      6. lower-*.f6490.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      7. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta} \]
      8. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
      9. lower-*.f6490.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
    7. Applied rewrites90.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta} \]
    8. Taylor expanded in delta around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\color{blue}{1 - {\sin \phi_1}^{2}}} \]
    9. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{1 - \color{blue}{\sin \phi_1 \cdot \sin \phi_1}} \]
      2. 1-sub-sinN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\color{blue}{\cos \phi_1 \cdot \cos \phi_1}} \]
      3. unpow2N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\color{blue}{{\cos \phi_1}^{2}}} \]
      4. lower-pow.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\color{blue}{{\cos \phi_1}^{2}}} \]
      5. lower-cos.f6499.6

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{{\color{blue}{\cos \phi_1}}^{2}} \]
    10. Applied rewrites99.6%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\color{blue}{{\cos \phi_1}^{2}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification92.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{{\cos \phi_1}^{2}} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 91.2% accurate, 2.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\cos \left(2 \cdot \phi_1\right), 0.5, 0.5\right)} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (let* ((t_1
         (+
          (atan2 (* (* (cos phi1) (sin delta)) (sin theta)) (cos delta))
          lambda1)))
   (if (<= delta -2.4e+19)
     t_1
     (if (<= delta 1.9e-9)
       (+
        (atan2
         (* (cos phi1) (* (sin delta) (sin theta)))
         (fma (cos (* 2.0 phi1)) 0.5 0.5))
        lambda1)
       t_1))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double t_1 = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1;
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = t_1;
	} else if (delta <= 1.9e-9) {
		tmp = atan2((cos(phi1) * (sin(delta) * sin(theta))), fma(cos((2.0 * phi1)), 0.5, 0.5)) + lambda1;
	} else {
		tmp = t_1;
	}
	return tmp;
}
function code(lambda1, phi1, phi2, delta, theta)
	t_1 = Float64(atan(Float64(Float64(cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1)
	tmp = 0.0
	if (delta <= -2.4e+19)
		tmp = t_1;
	elseif (delta <= 1.9e-9)
		tmp = Float64(atan(Float64(cos(phi1) * Float64(sin(delta) * sin(theta))), fma(cos(Float64(2.0 * phi1)), 0.5, 0.5)) + lambda1);
	else
		tmp = t_1;
	end
	return tmp
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := Block[{t$95$1 = N[(N[ArcTan[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]}, If[LessEqual[delta, -2.4e+19], t$95$1, If[LessEqual[delta, 1.9e-9], N[(N[ArcTan[N[(N[Cos[phi1], $MachinePrecision] * N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[Cos[N[(2.0 * phi1), $MachinePrecision]], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], t$95$1]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\
\mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\
\;\;\;\;\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\cos \left(2 \cdot \phi_1\right), 0.5, 0.5\right)} + \lambda_1\\

\mathbf{else}:\\
\;\;\;\;t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if delta < -2.4e19 or 1.90000000000000006e-9 < delta

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    4. Step-by-step derivation
      1. lower-cos.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    5. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta} \]
      2. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta} \]
      3. associate-*l*N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      4. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      5. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      6. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      7. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta} \]
      8. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
      9. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
    7. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta} \]

    if -2.4e19 < delta < 1.90000000000000006e-9

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      3. lift-sin.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      4. lift-asin.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \color{blue}{\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      5. sin-asinN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      6. lift-+.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)}} \]
      7. +-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \color{blue}{\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta + \sin \phi_1 \cdot \cos delta\right)}} \]
      8. distribute-rgt-inN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \color{blue}{\left(\left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1 + \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1\right)}} \]
      9. associate--r+N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right) \cdot \sin \phi_1\right) - \left(\sin \phi_1 \cdot \cos delta\right) \cdot \sin \phi_1}} \]
    4. Applied rewrites99.8%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\left(\cos delta - \left(\cos theta \cdot \left(\sin delta \cdot \cos \phi_1\right)\right) \cdot \sin \phi_1\right) - \left(0.5 - 0.5 \cdot \cos \left(2 \cdot \phi_1\right)\right) \cdot \cos delta}} \]
    5. Taylor expanded in delta around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right)}} \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot \phi_1\right) + \frac{1}{2}}} \]
      2. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos \left(2 \cdot \phi_1\right) \cdot \frac{1}{2}} + \frac{1}{2}} \]
      3. lower-fma.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\cos \left(2 \cdot \phi_1\right), \frac{1}{2}, \frac{1}{2}\right)}} \]
      4. lower-cos.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\color{blue}{\cos \left(2 \cdot \phi_1\right)}, \frac{1}{2}, \frac{1}{2}\right)} \]
      5. lower-*.f6499.5

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\mathsf{fma}\left(\cos \color{blue}{\left(2 \cdot \phi_1\right)}, 0.5, 0.5\right)} \]
    7. Applied rewrites99.5%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\mathsf{fma}\left(\cos \left(2 \cdot \phi_1\right), 0.5, 0.5\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification92.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{\cos \phi_1 \cdot \left(\sin delta \cdot \sin theta\right)}{\mathsf{fma}\left(\cos \left(2 \cdot \phi_1\right), 0.5, 0.5\right)} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 91.1% accurate, 2.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(delta \cdot \sin theta\right) \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (let* ((t_1
         (+
          (atan2 (* (* (cos phi1) (sin delta)) (sin theta)) (cos delta))
          lambda1)))
   (if (<= delta -2.4e+19)
     t_1
     (if (<= delta 1.9e-9)
       (+
        (atan2
         (* (* delta (sin theta)) (cos phi1))
         (- 1.0 (pow (sin phi1) 2.0)))
        lambda1)
       t_1))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double t_1 = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1;
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = t_1;
	} else if (delta <= 1.9e-9) {
		tmp = atan2(((delta * sin(theta)) * cos(phi1)), (1.0 - pow(sin(phi1), 2.0))) + lambda1;
	} else {
		tmp = t_1;
	}
	return tmp;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    real(8) :: t_1
    real(8) :: tmp
    t_1 = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1
    if (delta <= (-2.4d+19)) then
        tmp = t_1
    else if (delta <= 1.9d-9) then
        tmp = atan2(((delta * sin(theta)) * cos(phi1)), (1.0d0 - (sin(phi1) ** 2.0d0))) + lambda1
    else
        tmp = t_1
    end if
    code = tmp
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double t_1 = Math.atan2(((Math.cos(phi1) * Math.sin(delta)) * Math.sin(theta)), Math.cos(delta)) + lambda1;
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = t_1;
	} else if (delta <= 1.9e-9) {
		tmp = Math.atan2(((delta * Math.sin(theta)) * Math.cos(phi1)), (1.0 - Math.pow(Math.sin(phi1), 2.0))) + lambda1;
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(lambda1, phi1, phi2, delta, theta):
	t_1 = math.atan2(((math.cos(phi1) * math.sin(delta)) * math.sin(theta)), math.cos(delta)) + lambda1
	tmp = 0
	if delta <= -2.4e+19:
		tmp = t_1
	elif delta <= 1.9e-9:
		tmp = math.atan2(((delta * math.sin(theta)) * math.cos(phi1)), (1.0 - math.pow(math.sin(phi1), 2.0))) + lambda1
	else:
		tmp = t_1
	return tmp
function code(lambda1, phi1, phi2, delta, theta)
	t_1 = Float64(atan(Float64(Float64(cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1)
	tmp = 0.0
	if (delta <= -2.4e+19)
		tmp = t_1;
	elseif (delta <= 1.9e-9)
		tmp = Float64(atan(Float64(Float64(delta * sin(theta)) * cos(phi1)), Float64(1.0 - (sin(phi1) ^ 2.0))) + lambda1);
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(lambda1, phi1, phi2, delta, theta)
	t_1 = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1;
	tmp = 0.0;
	if (delta <= -2.4e+19)
		tmp = t_1;
	elseif (delta <= 1.9e-9)
		tmp = atan2(((delta * sin(theta)) * cos(phi1)), (1.0 - (sin(phi1) ^ 2.0))) + lambda1;
	else
		tmp = t_1;
	end
	tmp_2 = tmp;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := Block[{t$95$1 = N[(N[ArcTan[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]}, If[LessEqual[delta, -2.4e+19], t$95$1, If[LessEqual[delta, 1.9e-9], N[(N[ArcTan[N[(N[(delta * N[Sin[theta], $MachinePrecision]), $MachinePrecision] * N[Cos[phi1], $MachinePrecision]), $MachinePrecision] / N[(1.0 - N[Power[N[Sin[phi1], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], t$95$1]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\
\mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\
\;\;\;\;\tan^{-1}_* \frac{\left(delta \cdot \sin theta\right) \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} + \lambda_1\\

\mathbf{else}:\\
\;\;\;\;t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if delta < -2.4e19 or 1.90000000000000006e-9 < delta

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    4. Step-by-step derivation
      1. lower-cos.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    5. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta} \]
      2. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta} \]
      3. associate-*l*N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      4. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
      5. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      6. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
      7. lift-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta} \]
      8. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
      9. lower-*.f6485.0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
    7. Applied rewrites85.0%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta} \]

    if -2.4e19 < delta < 1.90000000000000006e-9

    1. Initial program 99.7%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in delta around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{1 - {\sin \phi_1}^{2}}} \]
    4. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{1 - {\sin \phi_1}^{2}}} \]
      2. lower-pow.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{1 - \color{blue}{{\sin \phi_1}^{2}}} \]
      3. lower-sin.f6499.4

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{1 - {\color{blue}{\sin \phi_1}}^{2}} \]
    5. Applied rewrites99.4%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{1 - {\sin \phi_1}^{2}}} \]
    6. Taylor expanded in delta around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(delta \cdot \sin theta\right)} \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot delta\right)} \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot delta\right)} \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} \]
      3. lower-sin.f6499.4

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\color{blue}{\sin theta} \cdot delta\right) \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} \]
    8. Applied rewrites99.4%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot delta\right)} \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification92.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;delta \leq 1.9 \cdot 10^{-9}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(delta \cdot \sin theta\right) \cdot \cos \phi_1}{1 - {\sin \phi_1}^{2}} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \]
  5. Add Preprocessing

Alternative 10: 88.5% accurate, 2.6× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+ (atan2 (* (* (cos phi1) (sin delta)) (sin theta)) (cos delta)) lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return Math.atan2(((Math.cos(phi1) * Math.sin(delta)) * Math.sin(theta)), Math.cos(delta)) + lambda1;
}
def code(lambda1, phi1, phi2, delta, theta):
	return math.atan2(((math.cos(phi1) * math.sin(delta)) * math.sin(theta)), math.cos(delta)) + lambda1
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(Float64(cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1)
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = atan2(((cos(phi1) * sin(delta)) * sin(theta)), cos(delta)) + lambda1;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[(N[Cos[phi1], $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in phi1 around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  4. Step-by-step derivation
    1. lower-cos.f6487.6

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  5. Applied rewrites87.6%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}}{\cos delta} \]
    2. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin theta \cdot \sin delta\right)} \cdot \cos \phi_1}{\cos delta} \]
    3. associate-*l*N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
    4. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\left(\sin delta \cdot \cos \phi_1\right)}}{\cos delta} \]
    5. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
    6. lower-*.f6487.6

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right) \cdot \sin theta}}{\cos delta} \]
    7. lift-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\sin delta \cdot \cos \phi_1\right)} \cdot \sin theta}{\cos delta} \]
    8. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
    9. lower-*.f6487.6

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right)} \cdot \sin theta}{\cos delta} \]
  7. Applied rewrites87.6%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}}{\cos delta} \]
  8. Final simplification87.6%

    \[\leadsto \tan^{-1}_* \frac{\left(\cos \phi_1 \cdot \sin delta\right) \cdot \sin theta}{\cos delta} + \lambda_1 \]
  9. Add Preprocessing

Alternative 11: 86.3% accurate, 3.3× speedup?

\[\begin{array}{l} \\ \tan^{-1}_* \frac{\sin delta \cdot \sin theta}{\cos delta} + \lambda_1 \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (+ (atan2 (* (sin delta) (sin theta)) (cos delta)) lambda1))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return atan2((sin(delta) * sin(theta)), cos(delta)) + lambda1;
}
real(8) function code(lambda1, phi1, phi2, delta, theta)
    real(8), intent (in) :: lambda1
    real(8), intent (in) :: phi1
    real(8), intent (in) :: phi2
    real(8), intent (in) :: delta
    real(8), intent (in) :: theta
    code = atan2((sin(delta) * sin(theta)), cos(delta)) + lambda1
end function
public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	return Math.atan2((Math.sin(delta) * Math.sin(theta)), Math.cos(delta)) + lambda1;
}
def code(lambda1, phi1, phi2, delta, theta):
	return math.atan2((math.sin(delta) * math.sin(theta)), math.cos(delta)) + lambda1
function code(lambda1, phi1, phi2, delta, theta)
	return Float64(atan(Float64(sin(delta) * sin(theta)), cos(delta)) + lambda1)
end
function tmp = code(lambda1, phi1, phi2, delta, theta)
	tmp = atan2((sin(delta) * sin(theta)), cos(delta)) + lambda1;
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Sin[delta], $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{\sin delta \cdot \sin theta}{\cos delta} + \lambda_1
\end{array}
Derivation
  1. Initial program 99.7%

    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in phi1 around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  4. Step-by-step derivation
    1. lower-cos.f6487.6

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  5. Applied rewrites87.6%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
  6. Taylor expanded in phi1 around 0

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
    2. lower-*.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
    3. lower-sin.f64N/A

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
    4. lower-sin.f6485.3

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
  8. Applied rewrites85.3%

    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
  9. Final simplification85.3%

    \[\leadsto \tan^{-1}_* \frac{\sin delta \cdot \sin theta}{\cos delta} + \lambda_1 \]
  10. Add Preprocessing

Alternative 12: 80.3% accurate, 4.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(theta \cdot theta, -0.16666666666666666, 1\right) \cdot \sin delta\right) \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;delta \leq 2.2 \cdot 10^{+24}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \end{array} \end{array} \]
(FPCore (lambda1 phi1 phi2 delta theta)
 :precision binary64
 (if (<= delta -2.4e+19)
   (+
    (atan2
     (* (* (fma (* theta theta) -0.16666666666666666 1.0) (sin delta)) theta)
     (cos delta))
    lambda1)
   (if (<= delta 2.2e+24)
     (+
      (atan2
       (* (* (fma (* -0.16666666666666666 delta) delta 1.0) (sin theta)) delta)
       (cos delta))
      lambda1)
     (+ (atan2 (* (sin delta) theta) (cos delta)) lambda1))))
double code(double lambda1, double phi1, double phi2, double delta, double theta) {
	double tmp;
	if (delta <= -2.4e+19) {
		tmp = atan2(((fma((theta * theta), -0.16666666666666666, 1.0) * sin(delta)) * theta), cos(delta)) + lambda1;
	} else if (delta <= 2.2e+24) {
		tmp = atan2(((fma((-0.16666666666666666 * delta), delta, 1.0) * sin(theta)) * delta), cos(delta)) + lambda1;
	} else {
		tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1;
	}
	return tmp;
}
function code(lambda1, phi1, phi2, delta, theta)
	tmp = 0.0
	if (delta <= -2.4e+19)
		tmp = Float64(atan(Float64(Float64(fma(Float64(theta * theta), -0.16666666666666666, 1.0) * sin(delta)) * theta), cos(delta)) + lambda1);
	elseif (delta <= 2.2e+24)
		tmp = Float64(atan(Float64(Float64(fma(Float64(-0.16666666666666666 * delta), delta, 1.0) * sin(theta)) * delta), cos(delta)) + lambda1);
	else
		tmp = Float64(atan(Float64(sin(delta) * theta), cos(delta)) + lambda1);
	end
	return tmp
end
code[lambda1_, phi1_, phi2_, delta_, theta_] := If[LessEqual[delta, -2.4e+19], N[(N[ArcTan[N[(N[(N[(N[(theta * theta), $MachinePrecision] * -0.16666666666666666 + 1.0), $MachinePrecision] * N[Sin[delta], $MachinePrecision]), $MachinePrecision] * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], If[LessEqual[delta, 2.2e+24], N[(N[ArcTan[N[(N[(N[(N[(-0.16666666666666666 * delta), $MachinePrecision] * delta + 1.0), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] * delta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], N[(N[ArcTan[N[(N[Sin[delta], $MachinePrecision] * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\
\;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(theta \cdot theta, -0.16666666666666666, 1\right) \cdot \sin delta\right) \cdot theta}{\cos delta} + \lambda_1\\

\mathbf{elif}\;delta \leq 2.2 \cdot 10^{+24}:\\
\;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\

\mathbf{else}:\\
\;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if delta < -2.4e19

    1. Initial program 99.8%

      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    4. Step-by-step derivation
      1. lower-cos.f6489.4

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    5. Applied rewrites89.4%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
    6. Taylor expanded in phi1 around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
      2. lower-*.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
      3. lower-sin.f64N/A

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
      4. lower-sin.f6485.4

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
    8. Applied rewrites85.4%

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
    9. Taylor expanded in theta around 0

      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\left(\sin delta + \frac{-1}{6} \cdot \left({theta}^{2} \cdot \sin delta\right)\right)}}{\cos delta} \]
    10. Step-by-step derivation
      1. Applied rewrites70.0%

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\mathsf{fma}\left(theta \cdot theta, -0.16666666666666666, 1\right) \cdot \sin delta\right) \cdot \color{blue}{theta}}{\cos delta} \]

      if -2.4e19 < delta < 2.20000000000000002e24

      1. Initial program 99.7%

        \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
      2. Add Preprocessing
      3. Taylor expanded in phi1 around 0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
      4. Step-by-step derivation
        1. lower-cos.f6490.6

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
      5. Applied rewrites90.6%

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
      6. Taylor expanded in phi1 around 0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
      7. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
        2. lower-*.f64N/A

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
        3. lower-sin.f64N/A

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
        4. lower-sin.f6489.3

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
      8. Applied rewrites89.3%

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
      9. Taylor expanded in delta around 0

        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{delta \cdot \color{blue}{\left(\sin theta + \frac{-1}{6} \cdot \left({delta}^{2} \cdot \sin theta\right)\right)}}{\cos delta} \]
      10. Step-by-step derivation
        1. Applied rewrites89.4%

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot \color{blue}{delta}}{\cos delta} \]

        if 2.20000000000000002e24 < delta

        1. Initial program 99.6%

          \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
        2. Add Preprocessing
        3. Taylor expanded in phi1 around 0

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
        4. Step-by-step derivation
          1. lower-cos.f6478.7

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
        5. Applied rewrites78.7%

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
        6. Taylor expanded in phi1 around 0

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
        7. Step-by-step derivation
          1. *-commutativeN/A

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
          2. lower-*.f64N/A

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
          3. lower-sin.f64N/A

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
          4. lower-sin.f6475.3

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
        8. Applied rewrites75.3%

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
        9. Taylor expanded in theta around 0

          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
        10. Step-by-step derivation
          1. Applied rewrites64.0%

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
        11. Recombined 3 regimes into one program.
        12. Final simplification79.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;delta \leq -2.4 \cdot 10^{+19}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(theta \cdot theta, -0.16666666666666666, 1\right) \cdot \sin delta\right) \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;delta \leq 2.2 \cdot 10^{+24}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \end{array} \]
        13. Add Preprocessing

        Alternative 13: 80.1% accurate, 4.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;theta \leq -2.5 \cdot 10^{+53}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \end{array} \]
        (FPCore (lambda1 phi1 phi2 delta theta)
         :precision binary64
         (if (<= theta -2.5e+53)
           (+
            (atan2
             (* (* (fma (* -0.16666666666666666 delta) delta 1.0) (sin theta)) delta)
             (cos delta))
            lambda1)
           (if (<= theta 1.52e-18)
             (+ (atan2 (* (sin delta) theta) (cos delta)) lambda1)
             (+ (atan2 (* delta (sin theta)) (cos delta)) lambda1))))
        double code(double lambda1, double phi1, double phi2, double delta, double theta) {
        	double tmp;
        	if (theta <= -2.5e+53) {
        		tmp = atan2(((fma((-0.16666666666666666 * delta), delta, 1.0) * sin(theta)) * delta), cos(delta)) + lambda1;
        	} else if (theta <= 1.52e-18) {
        		tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1;
        	} else {
        		tmp = atan2((delta * sin(theta)), cos(delta)) + lambda1;
        	}
        	return tmp;
        }
        
        function code(lambda1, phi1, phi2, delta, theta)
        	tmp = 0.0
        	if (theta <= -2.5e+53)
        		tmp = Float64(atan(Float64(Float64(fma(Float64(-0.16666666666666666 * delta), delta, 1.0) * sin(theta)) * delta), cos(delta)) + lambda1);
        	elseif (theta <= 1.52e-18)
        		tmp = Float64(atan(Float64(sin(delta) * theta), cos(delta)) + lambda1);
        	else
        		tmp = Float64(atan(Float64(delta * sin(theta)), cos(delta)) + lambda1);
        	end
        	return tmp
        end
        
        code[lambda1_, phi1_, phi2_, delta_, theta_] := If[LessEqual[theta, -2.5e+53], N[(N[ArcTan[N[(N[(N[(N[(-0.16666666666666666 * delta), $MachinePrecision] * delta + 1.0), $MachinePrecision] * N[Sin[theta], $MachinePrecision]), $MachinePrecision] * delta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], If[LessEqual[theta, 1.52e-18], N[(N[ArcTan[N[(N[Sin[delta], $MachinePrecision] * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], N[(N[ArcTan[N[(delta * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;theta \leq -2.5 \cdot 10^{+53}:\\
        \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\
        
        \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\
        \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\
        
        \mathbf{else}:\\
        \;\;\;\;\tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if theta < -2.5000000000000002e53

          1. Initial program 99.5%

            \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
          2. Add Preprocessing
          3. Taylor expanded in phi1 around 0

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
          4. Step-by-step derivation
            1. lower-cos.f6480.5

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
          5. Applied rewrites80.5%

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
          6. Taylor expanded in phi1 around 0

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
          7. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
            2. lower-*.f64N/A

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
            3. lower-sin.f64N/A

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
            4. lower-sin.f6479.3

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
          8. Applied rewrites79.3%

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
          9. Taylor expanded in delta around 0

            \[\leadsto \lambda_1 + \tan^{-1}_* \frac{delta \cdot \color{blue}{\left(\sin theta + \frac{-1}{6} \cdot \left({delta}^{2} \cdot \sin theta\right)\right)}}{\cos delta} \]
          10. Step-by-step derivation
            1. Applied rewrites62.0%

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot \color{blue}{delta}}{\cos delta} \]

            if -2.5000000000000002e53 < theta < 1.52e-18

            1. Initial program 99.7%

              \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
            2. Add Preprocessing
            3. Taylor expanded in phi1 around 0

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
            4. Step-by-step derivation
              1. lower-cos.f6492.4

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
            5. Applied rewrites92.4%

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
            6. Taylor expanded in phi1 around 0

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
            7. Step-by-step derivation
              1. *-commutativeN/A

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
              2. lower-*.f64N/A

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
              3. lower-sin.f64N/A

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
              4. lower-sin.f6489.9

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
            8. Applied rewrites89.9%

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
            9. Taylor expanded in theta around 0

              \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
            10. Step-by-step derivation
              1. Applied rewrites89.6%

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]

              if 1.52e-18 < theta

              1. Initial program 99.6%

                \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
              2. Add Preprocessing
              3. Taylor expanded in phi1 around 0

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
              4. Step-by-step derivation
                1. lower-cos.f6483.1

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
              5. Applied rewrites83.1%

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
              6. Taylor expanded in phi1 around 0

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
              7. Step-by-step derivation
                1. *-commutativeN/A

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                2. lower-*.f64N/A

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                3. lower-sin.f64N/A

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
                4. lower-sin.f6480.3

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
              8. Applied rewrites80.3%

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
              9. Taylor expanded in delta around 0

                \[\leadsto \lambda_1 + \tan^{-1}_* \frac{delta \cdot \color{blue}{\sin theta}}{\cos delta} \]
              10. Step-by-step derivation
                1. Applied rewrites69.5%

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{delta}}{\cos delta} \]
              11. Recombined 3 regimes into one program.
              12. Final simplification78.9%

                \[\leadsto \begin{array}{l} \mathbf{if}\;theta \leq -2.5 \cdot 10^{+53}:\\ \;\;\;\;\tan^{-1}_* \frac{\left(\mathsf{fma}\left(-0.16666666666666666 \cdot delta, delta, 1\right) \cdot \sin theta\right) \cdot delta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \]
              13. Add Preprocessing

              Alternative 14: 80.1% accurate, 4.2× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} t_1 := \tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{if}\;theta \leq -2.4 \cdot 10^{+50}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
              (FPCore (lambda1 phi1 phi2 delta theta)
               :precision binary64
               (let* ((t_1 (+ (atan2 (* delta (sin theta)) (cos delta)) lambda1)))
                 (if (<= theta -2.4e+50)
                   t_1
                   (if (<= theta 1.52e-18)
                     (+ (atan2 (* (sin delta) theta) (cos delta)) lambda1)
                     t_1))))
              double code(double lambda1, double phi1, double phi2, double delta, double theta) {
              	double t_1 = atan2((delta * sin(theta)), cos(delta)) + lambda1;
              	double tmp;
              	if (theta <= -2.4e+50) {
              		tmp = t_1;
              	} else if (theta <= 1.52e-18) {
              		tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1;
              	} else {
              		tmp = t_1;
              	}
              	return tmp;
              }
              
              real(8) function code(lambda1, phi1, phi2, delta, theta)
                  real(8), intent (in) :: lambda1
                  real(8), intent (in) :: phi1
                  real(8), intent (in) :: phi2
                  real(8), intent (in) :: delta
                  real(8), intent (in) :: theta
                  real(8) :: t_1
                  real(8) :: tmp
                  t_1 = atan2((delta * sin(theta)), cos(delta)) + lambda1
                  if (theta <= (-2.4d+50)) then
                      tmp = t_1
                  else if (theta <= 1.52d-18) then
                      tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1
                  else
                      tmp = t_1
                  end if
                  code = tmp
              end function
              
              public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
              	double t_1 = Math.atan2((delta * Math.sin(theta)), Math.cos(delta)) + lambda1;
              	double tmp;
              	if (theta <= -2.4e+50) {
              		tmp = t_1;
              	} else if (theta <= 1.52e-18) {
              		tmp = Math.atan2((Math.sin(delta) * theta), Math.cos(delta)) + lambda1;
              	} else {
              		tmp = t_1;
              	}
              	return tmp;
              }
              
              def code(lambda1, phi1, phi2, delta, theta):
              	t_1 = math.atan2((delta * math.sin(theta)), math.cos(delta)) + lambda1
              	tmp = 0
              	if theta <= -2.4e+50:
              		tmp = t_1
              	elif theta <= 1.52e-18:
              		tmp = math.atan2((math.sin(delta) * theta), math.cos(delta)) + lambda1
              	else:
              		tmp = t_1
              	return tmp
              
              function code(lambda1, phi1, phi2, delta, theta)
              	t_1 = Float64(atan(Float64(delta * sin(theta)), cos(delta)) + lambda1)
              	tmp = 0.0
              	if (theta <= -2.4e+50)
              		tmp = t_1;
              	elseif (theta <= 1.52e-18)
              		tmp = Float64(atan(Float64(sin(delta) * theta), cos(delta)) + lambda1);
              	else
              		tmp = t_1;
              	end
              	return tmp
              end
              
              function tmp_2 = code(lambda1, phi1, phi2, delta, theta)
              	t_1 = atan2((delta * sin(theta)), cos(delta)) + lambda1;
              	tmp = 0.0;
              	if (theta <= -2.4e+50)
              		tmp = t_1;
              	elseif (theta <= 1.52e-18)
              		tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1;
              	else
              		tmp = t_1;
              	end
              	tmp_2 = tmp;
              end
              
              code[lambda1_, phi1_, phi2_, delta_, theta_] := Block[{t$95$1 = N[(N[ArcTan[N[(delta * N[Sin[theta], $MachinePrecision]), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]}, If[LessEqual[theta, -2.4e+50], t$95$1, If[LessEqual[theta, 1.52e-18], N[(N[ArcTan[N[(N[Sin[delta], $MachinePrecision] * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision], t$95$1]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              t_1 := \tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\
              \mathbf{if}\;theta \leq -2.4 \cdot 10^{+50}:\\
              \;\;\;\;t\_1\\
              
              \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\
              \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\
              
              \mathbf{else}:\\
              \;\;\;\;t\_1\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if theta < -2.4000000000000002e50 or 1.52e-18 < theta

                1. Initial program 99.6%

                  \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
                2. Add Preprocessing
                3. Taylor expanded in phi1 around 0

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                4. Step-by-step derivation
                  1. lower-cos.f6481.8

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                5. Applied rewrites81.8%

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                6. Taylor expanded in phi1 around 0

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
                7. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                  2. lower-*.f64N/A

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                  3. lower-sin.f64N/A

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
                  4. lower-sin.f6479.7

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                8. Applied rewrites79.7%

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                9. Taylor expanded in delta around 0

                  \[\leadsto \lambda_1 + \tan^{-1}_* \frac{delta \cdot \color{blue}{\sin theta}}{\cos delta} \]
                10. Step-by-step derivation
                  1. Applied rewrites65.8%

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{delta}}{\cos delta} \]

                  if -2.4000000000000002e50 < theta < 1.52e-18

                  1. Initial program 99.7%

                    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
                  2. Add Preprocessing
                  3. Taylor expanded in phi1 around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  4. Step-by-step derivation
                    1. lower-cos.f6492.7

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  5. Applied rewrites92.7%

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  6. Taylor expanded in phi1 around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
                  7. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                    2. lower-*.f64N/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                    3. lower-sin.f64N/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
                    4. lower-sin.f6490.2

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                  8. Applied rewrites90.2%

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                  9. Taylor expanded in theta around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                  10. Step-by-step derivation
                    1. Applied rewrites90.2%

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                  11. Recombined 2 regimes into one program.
                  12. Final simplification78.8%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;theta \leq -2.4 \cdot 10^{+50}:\\ \;\;\;\;\tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\ \mathbf{elif}\;theta \leq 1.52 \cdot 10^{-18}:\\ \;\;\;\;\tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1}_* \frac{delta \cdot \sin theta}{\cos delta} + \lambda_1\\ \end{array} \]
                  13. Add Preprocessing

                  Alternative 15: 73.8% accurate, 4.3× speedup?

                  \[\begin{array}{l} \\ \tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1 \end{array} \]
                  (FPCore (lambda1 phi1 phi2 delta theta)
                   :precision binary64
                   (+ (atan2 (* (sin delta) theta) (cos delta)) lambda1))
                  double code(double lambda1, double phi1, double phi2, double delta, double theta) {
                  	return atan2((sin(delta) * theta), cos(delta)) + lambda1;
                  }
                  
                  real(8) function code(lambda1, phi1, phi2, delta, theta)
                      real(8), intent (in) :: lambda1
                      real(8), intent (in) :: phi1
                      real(8), intent (in) :: phi2
                      real(8), intent (in) :: delta
                      real(8), intent (in) :: theta
                      code = atan2((sin(delta) * theta), cos(delta)) + lambda1
                  end function
                  
                  public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
                  	return Math.atan2((Math.sin(delta) * theta), Math.cos(delta)) + lambda1;
                  }
                  
                  def code(lambda1, phi1, phi2, delta, theta):
                  	return math.atan2((math.sin(delta) * theta), math.cos(delta)) + lambda1
                  
                  function code(lambda1, phi1, phi2, delta, theta)
                  	return Float64(atan(Float64(sin(delta) * theta), cos(delta)) + lambda1)
                  end
                  
                  function tmp = code(lambda1, phi1, phi2, delta, theta)
                  	tmp = atan2((sin(delta) * theta), cos(delta)) + lambda1;
                  end
                  
                  code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(N[Sin[delta], $MachinePrecision] * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.7%

                    \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
                  2. Add Preprocessing
                  3. Taylor expanded in phi1 around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  4. Step-by-step derivation
                    1. lower-cos.f6487.6

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  5. Applied rewrites87.6%

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                  6. Taylor expanded in phi1 around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
                  7. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                    2. lower-*.f64N/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                    3. lower-sin.f64N/A

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
                    4. lower-sin.f6485.3

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                  8. Applied rewrites85.3%

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                  9. Taylor expanded in theta around 0

                    \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                  10. Step-by-step derivation
                    1. Applied rewrites72.0%

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                    2. Final simplification72.0%

                      \[\leadsto \tan^{-1}_* \frac{\sin delta \cdot theta}{\cos delta} + \lambda_1 \]
                    3. Add Preprocessing

                    Alternative 16: 67.9% accurate, 6.4× speedup?

                    \[\begin{array}{l} \\ \tan^{-1}_* \frac{delta \cdot theta}{\cos delta} + \lambda_1 \end{array} \]
                    (FPCore (lambda1 phi1 phi2 delta theta)
                     :precision binary64
                     (+ (atan2 (* delta theta) (cos delta)) lambda1))
                    double code(double lambda1, double phi1, double phi2, double delta, double theta) {
                    	return atan2((delta * theta), cos(delta)) + lambda1;
                    }
                    
                    real(8) function code(lambda1, phi1, phi2, delta, theta)
                        real(8), intent (in) :: lambda1
                        real(8), intent (in) :: phi1
                        real(8), intent (in) :: phi2
                        real(8), intent (in) :: delta
                        real(8), intent (in) :: theta
                        code = atan2((delta * theta), cos(delta)) + lambda1
                    end function
                    
                    public static double code(double lambda1, double phi1, double phi2, double delta, double theta) {
                    	return Math.atan2((delta * theta), Math.cos(delta)) + lambda1;
                    }
                    
                    def code(lambda1, phi1, phi2, delta, theta):
                    	return math.atan2((delta * theta), math.cos(delta)) + lambda1
                    
                    function code(lambda1, phi1, phi2, delta, theta)
                    	return Float64(atan(Float64(delta * theta), cos(delta)) + lambda1)
                    end
                    
                    function tmp = code(lambda1, phi1, phi2, delta, theta)
                    	tmp = atan2((delta * theta), cos(delta)) + lambda1;
                    end
                    
                    code[lambda1_, phi1_, phi2_, delta_, theta_] := N[(N[ArcTan[N[(delta * theta), $MachinePrecision] / N[Cos[delta], $MachinePrecision]], $MachinePrecision] + lambda1), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \tan^{-1}_* \frac{delta \cdot theta}{\cos delta} + \lambda_1
                    \end{array}
                    
                    Derivation
                    1. Initial program 99.7%

                      \[\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)} \]
                    2. Add Preprocessing
                    3. Taylor expanded in phi1 around 0

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                    4. Step-by-step derivation
                      1. lower-cos.f6487.6

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                    5. Applied rewrites87.6%

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\color{blue}{\cos delta}} \]
                    6. Taylor expanded in phi1 around 0

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin delta \cdot \sin theta}}{\cos delta} \]
                    7. Step-by-step derivation
                      1. *-commutativeN/A

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                      2. lower-*.f64N/A

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                      3. lower-sin.f64N/A

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta} \cdot \sin delta}{\cos delta} \]
                      4. lower-sin.f6485.3

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\sin theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                    8. Applied rewrites85.3%

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{\color{blue}{\sin theta \cdot \sin delta}}{\cos delta} \]
                    9. Taylor expanded in theta around 0

                      \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                    10. Step-by-step derivation
                      1. Applied rewrites72.0%

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot \color{blue}{\sin delta}}{\cos delta} \]
                      2. Taylor expanded in delta around 0

                        \[\leadsto \lambda_1 + \tan^{-1}_* \frac{delta \cdot theta}{\cos delta} \]
                      3. Step-by-step derivation
                        1. Applied rewrites67.1%

                          \[\leadsto \lambda_1 + \tan^{-1}_* \frac{theta \cdot delta}{\cos delta} \]
                        2. Final simplification67.1%

                          \[\leadsto \tan^{-1}_* \frac{delta \cdot theta}{\cos delta} + \lambda_1 \]
                        3. Add Preprocessing

                        Reproduce

                        ?
                        herbie shell --seed 2024235 
                        (FPCore (lambda1 phi1 phi2 delta theta)
                          :name "Destination given bearing on a great circle"
                          :precision binary64
                          (+ lambda1 (atan2 (* (* (sin theta) (sin delta)) (cos phi1)) (- (cos delta) (* (sin phi1) (sin (asin (+ (* (sin phi1) (cos delta)) (* (* (cos phi1) (sin delta)) (cos theta))))))))))