Beckmann Sample, normalization factor

Percentage Accurate: 97.9% → 98.5%
Time: 18.7s
Alternatives: 14
Speedup: 1.0×

Specification

?
\[\left(0 < cosTheta \land cosTheta < 0.9999\right) \land \left(-1 < c \land c < 1\right)\]
\[\begin{array}{l} \\ \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (+ 1.0 c)
   (*
    (* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
    (exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
	return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta)))))
end
function tmp = code(cosTheta, c)
	tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta))));
end
\begin{array}{l}

\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}

Sampling outcomes in binary32 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 14 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: 97.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (+ 1.0 c)
   (*
    (* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
    (exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
	return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta)))))
end
function tmp = code(cosTheta, c)
	tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta))));
end
\begin{array}{l}

\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}

Alternative 1: 98.5% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta \cdot \sqrt{\pi}}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   1.0
   (fma
    (/ (sqrt (+ 1.0 (* cosTheta -2.0))) (* cosTheta (sqrt PI)))
    (pow (exp (- cosTheta)) cosTheta)
    c))))
float code(float cosTheta, float c) {
	return 1.0f / (1.0f + fmaf((sqrtf((1.0f + (cosTheta * -2.0f))) / (cosTheta * sqrtf(((float) M_PI)))), powf(expf(-cosTheta), cosTheta), c));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(1.0) + fma(Float32(sqrt(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0)))) / Float32(cosTheta * sqrt(Float32(pi)))), (exp(Float32(-cosTheta)) ^ cosTheta), c)))
end
\begin{array}{l}

\\
\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta \cdot \sqrt{\pi}}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Final simplification98.6%

    \[\leadsto \frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta \cdot \sqrt{\pi}}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)} \]
  6. Add Preprocessing

Alternative 2: 98.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + \left(c + e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}{cosTheta}\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   1.0
   (+
    c
    (*
     (exp (- (pow cosTheta 2.0)))
     (/
      (sqrt (* cosTheta (- (/ 1.0 (* cosTheta PI)) (/ 2.0 PI))))
      cosTheta))))))
float code(float cosTheta, float c) {
	return 1.0f / (1.0f + (c + (expf(-powf(cosTheta, 2.0f)) * (sqrtf((cosTheta * ((1.0f / (cosTheta * ((float) M_PI))) - (2.0f / ((float) M_PI))))) / cosTheta))));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(exp(Float32(-(cosTheta ^ Float32(2.0)))) * Float32(sqrt(Float32(cosTheta * Float32(Float32(Float32(1.0) / Float32(cosTheta * Float32(pi))) - Float32(Float32(2.0) / Float32(pi))))) / cosTheta)))))
end
function tmp = code(cosTheta, c)
	tmp = single(1.0) / (single(1.0) + (c + (exp(-(cosTheta ^ single(2.0))) * (sqrt((cosTheta * ((single(1.0) / (cosTheta * single(pi))) - (single(2.0) / single(pi))))) / cosTheta))));
end
\begin{array}{l}

\\
\frac{1}{1 + \left(c + e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}{cosTheta}\right)}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in c around 0 98.0%

    \[\leadsto \frac{1}{1 + \color{blue}{\left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 + -2 \cdot cosTheta}{\pi}}\right)}} \]
  6. Taylor expanded in cosTheta around inf 98.1%

    \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\color{blue}{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - 2 \cdot \frac{1}{\pi}\right)}}\right)} \]
  7. Step-by-step derivation
    1. associate-*r/98.1%

      \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \color{blue}{\frac{2 \cdot 1}{\pi}}\right)}\right)} \]
    2. metadata-eval98.1%

      \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{\color{blue}{2}}{\pi}\right)}\right)} \]
  8. Simplified98.1%

    \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\color{blue}{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}\right)} \]
  9. Step-by-step derivation
    1. associate-*l/98.2%

      \[\leadsto \frac{1}{1 + \left(c + \color{blue}{\frac{e^{-1 \cdot {cosTheta}^{2}} \cdot \sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}{cosTheta}}\right)} \]
    2. mul-1-neg98.2%

      \[\leadsto \frac{1}{1 + \left(c + \frac{e^{\color{blue}{-{cosTheta}^{2}}} \cdot \sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}{cosTheta}\right)} \]
    3. associate-/r*98.1%

      \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-{cosTheta}^{2}} \cdot \sqrt{cosTheta \cdot \left(\color{blue}{\frac{\frac{1}{cosTheta}}{\pi}} - \frac{2}{\pi}\right)}}{cosTheta}\right)} \]
  10. Applied egg-rr98.1%

    \[\leadsto \frac{1}{1 + \left(c + \color{blue}{\frac{e^{-{cosTheta}^{2}} \cdot \sqrt{cosTheta \cdot \left(\frac{\frac{1}{cosTheta}}{\pi} - \frac{2}{\pi}\right)}}{cosTheta}}\right)} \]
  11. Step-by-step derivation
    1. associate-/l*98.0%

      \[\leadsto \frac{1}{1 + \left(c + \color{blue}{e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\frac{\frac{1}{cosTheta}}{\pi} - \frac{2}{\pi}\right)}}{cosTheta}}\right)} \]
    2. associate-/l/98.1%

      \[\leadsto \frac{1}{1 + \left(c + e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\color{blue}{\frac{1}{\pi \cdot cosTheta}} - \frac{2}{\pi}\right)}}{cosTheta}\right)} \]
  12. Simplified98.1%

    \[\leadsto \frac{1}{1 + \left(c + \color{blue}{e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\frac{1}{\pi \cdot cosTheta} - \frac{2}{\pi}\right)}}{cosTheta}}\right)} \]
  13. Final simplification98.1%

    \[\leadsto \frac{1}{1 + \left(c + e^{-{cosTheta}^{2}} \cdot \frac{\sqrt{cosTheta \cdot \left(\frac{1}{cosTheta \cdot \pi} - \frac{2}{\pi}\right)}}{cosTheta}\right)} \]
  14. Add Preprocessing

Alternative 3: 98.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + \left(c + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   1.0
   (+
    c
    (*
     (/ (exp (- (pow cosTheta 2.0))) cosTheta)
     (sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI)))))))
float code(float cosTheta, float c) {
	return 1.0f / (1.0f + (c + ((expf(-powf(cosTheta, 2.0f)) / cosTheta) * sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI))))));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(exp(Float32(-(cosTheta ^ Float32(2.0)))) / cosTheta) * sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi)))))))
end
function tmp = code(cosTheta, c)
	tmp = single(1.0) / (single(1.0) + (c + ((exp(-(cosTheta ^ single(2.0))) / cosTheta) * sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi))))));
end
\begin{array}{l}

\\
\frac{1}{1 + \left(c + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}\right)}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in c around 0 98.0%

    \[\leadsto \frac{1}{1 + \color{blue}{\left(c + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 + -2 \cdot cosTheta}{\pi}}\right)}} \]
  6. Final simplification98.0%

    \[\leadsto \frac{1}{1 + \left(c + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}\right)} \]
  7. Add Preprocessing

Alternative 4: 97.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 - cosTheta \cdot 2}{\pi}}} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   1.0
   (*
    (/ (exp (- (pow cosTheta 2.0))) cosTheta)
    (sqrt (/ (- 1.0 (* cosTheta 2.0)) PI))))))
float code(float cosTheta, float c) {
	return 1.0f / (1.0f + ((expf(-powf(cosTheta, 2.0f)) / cosTheta) * sqrtf(((1.0f - (cosTheta * 2.0f)) / ((float) M_PI)))));
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(Float32(exp(Float32(-(cosTheta ^ Float32(2.0)))) / cosTheta) * sqrt(Float32(Float32(Float32(1.0) - Float32(cosTheta * Float32(2.0))) / Float32(pi))))))
end
function tmp = code(cosTheta, c)
	tmp = single(1.0) / (single(1.0) + ((exp(-(cosTheta ^ single(2.0))) / cosTheta) * sqrt(((single(1.0) - (cosTheta * single(2.0))) / single(pi)))));
end
\begin{array}{l}

\\
\frac{1}{1 + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 - cosTheta \cdot 2}{\pi}}}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Taylor expanded in c around 0 97.5%

    \[\leadsto \color{blue}{\frac{1}{1 + \frac{e^{-1 \cdot {cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 - 2 \cdot cosTheta}{\pi}}}} \]
  4. Final simplification97.5%

    \[\leadsto \frac{1}{1 + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 - cosTheta \cdot 2}{\pi}}} \]
  5. Add Preprocessing

Alternative 5: 95.3% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\frac{1}{\pi}}\\ \frac{1}{c + \left(t\_0 \cdot \frac{1}{cosTheta} + \left(1 + t\_0 \cdot \left(-1 - cosTheta\right)\right)\right)} \end{array} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (let* ((t_0 (sqrt (/ 1.0 PI))))
   (/
    1.0
    (+ c (+ (* t_0 (/ 1.0 cosTheta)) (+ 1.0 (* t_0 (- -1.0 cosTheta))))))))
float code(float cosTheta, float c) {
	float t_0 = sqrtf((1.0f / ((float) M_PI)));
	return 1.0f / (c + ((t_0 * (1.0f / cosTheta)) + (1.0f + (t_0 * (-1.0f - cosTheta)))));
}
function code(cosTheta, c)
	t_0 = sqrt(Float32(Float32(1.0) / Float32(pi)))
	return Float32(Float32(1.0) / Float32(c + Float32(Float32(t_0 * Float32(Float32(1.0) / cosTheta)) + Float32(Float32(1.0) + Float32(t_0 * Float32(Float32(-1.0) - cosTheta))))))
end
function tmp = code(cosTheta, c)
	t_0 = sqrt((single(1.0) / single(pi)));
	tmp = single(1.0) / (c + ((t_0 * (single(1.0) / cosTheta)) + (single(1.0) + (t_0 * (single(-1.0) - cosTheta)))));
end
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\frac{1}{\pi}}\\
\frac{1}{c + \left(t\_0 \cdot \frac{1}{cosTheta} + \left(1 + t\_0 \cdot \left(-1 - cosTheta\right)\right)\right)}
\end{array}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. +-commutative98.0%

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(1 + c\right)}} \]
    2. fma-define98.0%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)}} \]
    3. associate-*l/98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\frac{1 \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\pi}}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    4. *-lft-identity98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    5. associate--l-98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 - \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    6. sub-neg98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 + \left(-\left(cosTheta + cosTheta\right)\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    7. neg-mul-198.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{-1 \cdot \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    8. distribute-lft-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{\left(-1 \cdot cosTheta + -1 \cdot cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    9. distribute-rgt-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{cosTheta \cdot \left(-1 + -1\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    10. metadata-eval98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot \color{blue}{-2}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    11. distribute-lft-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{-cosTheta \cdot cosTheta}}, 1 + c\right)} \]
    12. distribute-rgt-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{cosTheta \cdot \left(-cosTheta\right)}}, 1 + c\right)} \]
    13. exp-prod98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, \color{blue}{{\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}}, 1 + c\right)} \]
  3. Simplified98.5%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 + -1 \cdot cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{1 + \color{blue}{\left(-cosTheta\right)}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
    2. unsub-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  7. Simplified95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  8. Taylor expanded in cosTheta around 0 95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(1 + \left(c + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)}{cosTheta}}} \]
  9. Step-by-step derivation
    1. associate-+r+95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(\left(1 + c\right) + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}}{cosTheta}} \]
    2. distribute-lft-out95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + \color{blue}{-1 \cdot \left(\sqrt{\frac{1}{\pi}} + cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    3. distribute-rgt1-in95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \color{blue}{\left(\left(cosTheta + 1\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    4. +-commutative95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\color{blue}{\left(1 + cosTheta\right)} \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}} \]
  10. Simplified95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\left(1 + cosTheta\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}}} \]
  11. Taylor expanded in c around 0 95.1%

    \[\leadsto \frac{1}{\color{blue}{c + \left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right)\right)}} \]
  12. Final simplification95.1%

    \[\leadsto \frac{1}{c + \left(\sqrt{\frac{1}{\pi}} \cdot \frac{1}{cosTheta} + \left(1 + \sqrt{\frac{1}{\pi}} \cdot \left(-1 - cosTheta\right)\right)\right)} \]
  13. Add Preprocessing

Alternative 6: 95.4% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\frac{1}{\pi}}\\ \frac{1}{\frac{t\_0 + cosTheta \cdot \left(\left(1 + c\right) + t\_0 \cdot \left(-1 - cosTheta\right)\right)}{cosTheta}} \end{array} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (let* ((t_0 (sqrt (/ 1.0 PI))))
   (/
    1.0
    (/
     (+ t_0 (* cosTheta (+ (+ 1.0 c) (* t_0 (- -1.0 cosTheta)))))
     cosTheta))))
float code(float cosTheta, float c) {
	float t_0 = sqrtf((1.0f / ((float) M_PI)));
	return 1.0f / ((t_0 + (cosTheta * ((1.0f + c) + (t_0 * (-1.0f - cosTheta))))) / cosTheta);
}
function code(cosTheta, c)
	t_0 = sqrt(Float32(Float32(1.0) / Float32(pi)))
	return Float32(Float32(1.0) / Float32(Float32(t_0 + Float32(cosTheta * Float32(Float32(Float32(1.0) + c) + Float32(t_0 * Float32(Float32(-1.0) - cosTheta))))) / cosTheta))
end
function tmp = code(cosTheta, c)
	t_0 = sqrt((single(1.0) / single(pi)));
	tmp = single(1.0) / ((t_0 + (cosTheta * ((single(1.0) + c) + (t_0 * (single(-1.0) - cosTheta))))) / cosTheta);
end
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\frac{1}{\pi}}\\
\frac{1}{\frac{t\_0 + cosTheta \cdot \left(\left(1 + c\right) + t\_0 \cdot \left(-1 - cosTheta\right)\right)}{cosTheta}}
\end{array}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. +-commutative98.0%

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(1 + c\right)}} \]
    2. fma-define98.0%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)}} \]
    3. associate-*l/98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\frac{1 \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\pi}}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    4. *-lft-identity98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    5. associate--l-98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 - \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    6. sub-neg98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 + \left(-\left(cosTheta + cosTheta\right)\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    7. neg-mul-198.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{-1 \cdot \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    8. distribute-lft-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{\left(-1 \cdot cosTheta + -1 \cdot cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    9. distribute-rgt-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{cosTheta \cdot \left(-1 + -1\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    10. metadata-eval98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot \color{blue}{-2}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    11. distribute-lft-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{-cosTheta \cdot cosTheta}}, 1 + c\right)} \]
    12. distribute-rgt-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{cosTheta \cdot \left(-cosTheta\right)}}, 1 + c\right)} \]
    13. exp-prod98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, \color{blue}{{\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}}, 1 + c\right)} \]
  3. Simplified98.5%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 + -1 \cdot cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{1 + \color{blue}{\left(-cosTheta\right)}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
    2. unsub-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  7. Simplified95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  8. Taylor expanded in cosTheta around 0 95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(1 + \left(c + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)}{cosTheta}}} \]
  9. Step-by-step derivation
    1. associate-+r+95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(\left(1 + c\right) + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}}{cosTheta}} \]
    2. distribute-lft-out95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + \color{blue}{-1 \cdot \left(\sqrt{\frac{1}{\pi}} + cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    3. distribute-rgt1-in95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \color{blue}{\left(\left(cosTheta + 1\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    4. +-commutative95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\color{blue}{\left(1 + cosTheta\right)} \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}} \]
  10. Simplified95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\left(1 + cosTheta\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}}} \]
  11. Final simplification95.2%

    \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + \sqrt{\frac{1}{\pi}} \cdot \left(-1 - cosTheta\right)\right)}{cosTheta}} \]
  12. Add Preprocessing

Alternative 7: 95.4% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\frac{1}{\pi}}\\ \frac{1}{\left(\left(1 + c\right) + t\_0 \cdot \left(-1 - cosTheta\right)\right) + \frac{t\_0}{cosTheta}} \end{array} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (let* ((t_0 (sqrt (/ 1.0 PI))))
   (/ 1.0 (+ (+ (+ 1.0 c) (* t_0 (- -1.0 cosTheta))) (/ t_0 cosTheta)))))
float code(float cosTheta, float c) {
	float t_0 = sqrtf((1.0f / ((float) M_PI)));
	return 1.0f / (((1.0f + c) + (t_0 * (-1.0f - cosTheta))) + (t_0 / cosTheta));
}
function code(cosTheta, c)
	t_0 = sqrt(Float32(Float32(1.0) / Float32(pi)))
	return Float32(Float32(1.0) / Float32(Float32(Float32(Float32(1.0) + c) + Float32(t_0 * Float32(Float32(-1.0) - cosTheta))) + Float32(t_0 / cosTheta)))
end
function tmp = code(cosTheta, c)
	t_0 = sqrt((single(1.0) / single(pi)));
	tmp = single(1.0) / (((single(1.0) + c) + (t_0 * (single(-1.0) - cosTheta))) + (t_0 / cosTheta));
end
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\frac{1}{\pi}}\\
\frac{1}{\left(\left(1 + c\right) + t\_0 \cdot \left(-1 - cosTheta\right)\right) + \frac{t\_0}{cosTheta}}
\end{array}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. +-commutative98.0%

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(1 + c\right)}} \]
    2. fma-define98.0%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)}} \]
    3. associate-*l/98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\frac{1 \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\pi}}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    4. *-lft-identity98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    5. associate--l-98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 - \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    6. sub-neg98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{\color{blue}{1 + \left(-\left(cosTheta + cosTheta\right)\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    7. neg-mul-198.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{-1 \cdot \left(cosTheta + cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    8. distribute-lft-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{\left(-1 \cdot cosTheta + -1 \cdot cosTheta\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    9. distribute-rgt-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + \color{blue}{cosTheta \cdot \left(-1 + -1\right)}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    10. metadata-eval98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot \color{blue}{-2}}}{cosTheta}}{\sqrt{\pi}}, e^{\left(-cosTheta\right) \cdot cosTheta}, 1 + c\right)} \]
    11. distribute-lft-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{-cosTheta \cdot cosTheta}}, 1 + c\right)} \]
    12. distribute-rgt-neg-out98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, e^{\color{blue}{cosTheta \cdot \left(-cosTheta\right)}}, 1 + c\right)} \]
    13. exp-prod98.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, \color{blue}{{\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}}, 1 + c\right)} \]
  3. Simplified98.5%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 + -1 \cdot cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{1 + \color{blue}{\left(-cosTheta\right)}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
    2. unsub-neg95.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  7. Simplified95.5%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{\frac{\color{blue}{1 - cosTheta}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)} \]
  8. Taylor expanded in cosTheta around 0 95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(1 + \left(c + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)}{cosTheta}}} \]
  9. Step-by-step derivation
    1. associate-+r+95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(\left(1 + c\right) + \left(-1 \cdot \sqrt{\frac{1}{\pi}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}}{cosTheta}} \]
    2. distribute-lft-out95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + \color{blue}{-1 \cdot \left(\sqrt{\frac{1}{\pi}} + cosTheta \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    3. distribute-rgt1-in95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \color{blue}{\left(\left(cosTheta + 1\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right)}{cosTheta}} \]
    4. +-commutative95.2%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\color{blue}{\left(1 + cosTheta\right)} \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}} \]
  10. Simplified95.2%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(1 + c\right) + -1 \cdot \left(\left(1 + cosTheta\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right)}{cosTheta}}} \]
  11. Taylor expanded in c around 0 95.1%

    \[\leadsto \frac{1}{\color{blue}{c + \left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right)\right)}} \]
  12. Step-by-step derivation
    1. +-commutative95.1%

      \[\leadsto \frac{1}{c + \color{blue}{\left(\left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right) + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right)}} \]
    2. associate-+r+95.1%

      \[\leadsto \frac{1}{c + \color{blue}{\left(1 + \left(-1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right) + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right)\right)}} \]
    3. +-commutative95.1%

      \[\leadsto \frac{1}{\color{blue}{\left(1 + \left(-1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right) + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right)\right) + c}} \]
    4. associate-+r+95.1%

      \[\leadsto \frac{1}{\color{blue}{\left(\left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right) + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right)} + c} \]
    5. +-commutative95.1%

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right)\right)} + c} \]
    6. associate-+l+95.1%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \left(\left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right) + c\right)}} \]
    7. associate-*l/95.1%

      \[\leadsto \frac{1}{\color{blue}{\frac{1 \cdot \sqrt{\frac{1}{\pi}}}{cosTheta}} + \left(\left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right) + c\right)} \]
    8. *-lft-identity95.1%

      \[\leadsto \frac{1}{\frac{\color{blue}{\sqrt{\frac{1}{\pi}}}}{cosTheta} + \left(\left(1 + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right) + c\right)} \]
    9. associate-+r+95.1%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}}}{cosTheta} + \color{blue}{\left(1 + \left(-1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right) + c\right)\right)}} \]
    10. +-commutative95.1%

      \[\leadsto \frac{1}{\frac{\sqrt{\frac{1}{\pi}}}{cosTheta} + \left(1 + \color{blue}{\left(c + -1 \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)\right)}\right)} \]
  13. Simplified95.1%

    \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{cosTheta} + \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}} \cdot \left(1 + cosTheta\right)\right)}} \]
  14. Final simplification95.1%

    \[\leadsto \frac{1}{\left(\left(1 + c\right) + \sqrt{\frac{1}{\pi}} \cdot \left(-1 - cosTheta\right)\right) + \frac{\sqrt{\frac{1}{\pi}}}{cosTheta}} \]
  15. Add Preprocessing

Alternative 8: 95.7% accurate, 1.5× speedup?

\[\begin{array}{l} \\ cosTheta \cdot \left(\sqrt{\pi} + \pi \cdot \left(cosTheta \cdot \left(\sqrt{\frac{1}{\pi}} + \left(-1 - c\right)\right)\right)\right) \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (*
  cosTheta
  (+ (sqrt PI) (* PI (* cosTheta (+ (sqrt (/ 1.0 PI)) (- -1.0 c)))))))
float code(float cosTheta, float c) {
	return cosTheta * (sqrtf(((float) M_PI)) + (((float) M_PI) * (cosTheta * (sqrtf((1.0f / ((float) M_PI))) + (-1.0f - c)))));
}
function code(cosTheta, c)
	return Float32(cosTheta * Float32(sqrt(Float32(pi)) + Float32(Float32(pi) * Float32(cosTheta * Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) + Float32(Float32(-1.0) - c))))))
end
function tmp = code(cosTheta, c)
	tmp = cosTheta * (sqrt(single(pi)) + (single(pi) * (cosTheta * (sqrt((single(1.0) / single(pi))) + (single(-1.0) - c)))));
end
\begin{array}{l}

\\
cosTheta \cdot \left(\sqrt{\pi} + \pi \cdot \left(cosTheta \cdot \left(\sqrt{\frac{1}{\pi}} + \left(-1 - c\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} + -1 \cdot \left(cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \color{blue}{\left(-cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)}\right) \]
    2. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \color{blue}{\left(\sqrt{\pi} - cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
    3. associate-*r*95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \]
    4. *-commutative95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\left(\pi \cdot cosTheta\right)} \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right) \]
    5. associate-*l*95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\pi \cdot \left(cosTheta \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right) \]
    6. associate-+r+95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \pi \cdot \left(cosTheta \cdot \color{blue}{\left(\left(1 + c\right) + -1 \cdot \sqrt{\frac{1}{\pi}}\right)}\right)\right) \]
    7. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \pi \cdot \left(cosTheta \cdot \left(\left(1 + c\right) + \color{blue}{\left(-\sqrt{\frac{1}{\pi}}\right)}\right)\right)\right) \]
    8. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \pi \cdot \left(cosTheta \cdot \color{blue}{\left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)}\right)\right) \]
  7. Simplified95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} - \pi \cdot \left(cosTheta \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)\right)} \]
  8. Final simplification95.0%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \pi \cdot \left(cosTheta \cdot \left(\sqrt{\frac{1}{\pi}} + \left(-1 - c\right)\right)\right)\right) \]
  9. Add Preprocessing

Alternative 9: 95.7% accurate, 1.5× speedup?

\[\begin{array}{l} \\ cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \left(\sqrt{\frac{1}{\pi}} - c\right)\right)\right) \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (*
  cosTheta
  (+ (sqrt PI) (* (* cosTheta PI) (+ -1.0 (- (sqrt (/ 1.0 PI)) c))))))
float code(float cosTheta, float c) {
	return cosTheta * (sqrtf(((float) M_PI)) + ((cosTheta * ((float) M_PI)) * (-1.0f + (sqrtf((1.0f / ((float) M_PI))) - c))));
}
function code(cosTheta, c)
	return Float32(cosTheta * Float32(sqrt(Float32(pi)) + Float32(Float32(cosTheta * Float32(pi)) * Float32(Float32(-1.0) + Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) - c)))))
end
function tmp = code(cosTheta, c)
	tmp = cosTheta * (sqrt(single(pi)) + ((cosTheta * single(pi)) * (single(-1.0) + (sqrt((single(1.0) / single(pi))) - c))));
end
\begin{array}{l}

\\
cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \left(\sqrt{\frac{1}{\pi}} - c\right)\right)\right)
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-cube-cbrt98.0%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\color{blue}{\left(\left(\sqrt[3]{\frac{1}{\sqrt{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right)} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. cbrt-unprod98.0%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\color{blue}{\sqrt[3]{\frac{1}{\sqrt{\pi}} \cdot \frac{1}{\sqrt{\pi}}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. frac-times98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\color{blue}{\frac{1 \cdot 1}{\sqrt{\pi} \cdot \sqrt{\pi}}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. metadata-eval98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{\color{blue}{1}}{\sqrt{\pi} \cdot \sqrt{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. add-sqr-sqrt98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\color{blue}{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    6. inv-pow98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{\color{blue}{{\left(\sqrt{\pi}\right)}^{-1}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. sqrt-pow298.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{\color{blue}{{\pi}^{\left(\frac{-1}{2}\right)}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. metadata-eval98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{{\pi}^{\color{blue}{-0.5}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Applied egg-rr98.1%

    \[\leadsto \frac{1}{\left(1 + c\right) + \left(\color{blue}{\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{{\pi}^{-0.5}}\right)} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  5. Taylor expanded in cosTheta around 0 95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} + -1 \cdot \left(cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \color{blue}{\left(-cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)}\right) \]
    2. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \color{blue}{\left(\sqrt{\pi} - cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
    3. associate-*r*95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \]
    4. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c + \color{blue}{\left(-\sqrt{\frac{1}{\pi}}\right)}\right)\right)\right) \]
    5. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \left(cosTheta \cdot \pi\right) \cdot \left(1 + \color{blue}{\left(c - \sqrt{\frac{1}{\pi}}\right)}\right)\right) \]
  7. Simplified95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} - \left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c - \sqrt{\frac{1}{\pi}}\right)\right)\right)} \]
  8. Final simplification95.0%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \left(\sqrt{\frac{1}{\pi}} - c\right)\right)\right) \]
  9. Add Preprocessing

Alternative 10: 95.5% accurate, 1.5× speedup?

\[\begin{array}{l} \\ cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \sqrt{\frac{1}{\pi}}\right)\right) \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (* cosTheta (+ (sqrt PI) (* (* cosTheta PI) (+ -1.0 (sqrt (/ 1.0 PI)))))))
float code(float cosTheta, float c) {
	return cosTheta * (sqrtf(((float) M_PI)) + ((cosTheta * ((float) M_PI)) * (-1.0f + sqrtf((1.0f / ((float) M_PI))))));
}
function code(cosTheta, c)
	return Float32(cosTheta * Float32(sqrt(Float32(pi)) + Float32(Float32(cosTheta * Float32(pi)) * Float32(Float32(-1.0) + sqrt(Float32(Float32(1.0) / Float32(pi)))))))
end
function tmp = code(cosTheta, c)
	tmp = cosTheta * (sqrt(single(pi)) + ((cosTheta * single(pi)) * (single(-1.0) + sqrt((single(1.0) / single(pi))))));
end
\begin{array}{l}

\\
cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \sqrt{\frac{1}{\pi}}\right)\right)
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)}{cosTheta}}} \]
  6. Step-by-step derivation
    1. +-commutative94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(-1 \cdot \sqrt{\frac{1}{\pi}} + c\right)}}{cosTheta}} \]
    2. mul-1-neg94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\color{blue}{\left(-\sqrt{\frac{1}{\pi}}\right)} + c\right)}{cosTheta}} \]
  7. Simplified94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(-\sqrt{\frac{1}{\pi}}\right) + c\right)}{cosTheta}}} \]
  8. Taylor expanded in cosTheta around 0 95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} + -1 \cdot \left(cosTheta \cdot \left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
  9. Step-by-step derivation
    1. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \color{blue}{\left(-cosTheta \cdot \left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right) \]
    2. *-commutative95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\color{blue}{\left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right) \cdot cosTheta}\right)\right) \]
    3. sub-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \color{blue}{\left(\left(1 + c\right) + \left(-\sqrt{\frac{1}{\pi}}\right)\right)}\right) \cdot cosTheta\right)\right) \]
    4. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \left(\left(1 + c\right) + \color{blue}{-1 \cdot \sqrt{\frac{1}{\pi}}}\right)\right) \cdot cosTheta\right)\right) \]
    5. associate-+r+95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \color{blue}{\left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \cdot cosTheta\right)\right) \]
    6. *-commutative95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\color{blue}{cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right)\right) \]
    7. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \color{blue}{\left(\sqrt{\pi} - cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
    8. associate-*r*95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \]
  10. Simplified95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} - \left(\pi \cdot cosTheta\right) \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)} \]
  11. Taylor expanded in c around 0 94.9%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \left(\pi \cdot cosTheta\right) \cdot \color{blue}{\left(1 - \sqrt{\frac{1}{\pi}}\right)}\right) \]
  12. Final simplification94.9%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(-1 + \sqrt{\frac{1}{\pi}}\right)\right) \]
  13. Add Preprocessing

Alternative 11: 94.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \frac{1}{\mathsf{fma}\left(\sqrt{\frac{1}{\pi}}, -1 + \frac{1}{cosTheta}, 1\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/ 1.0 (fma (sqrt (/ 1.0 PI)) (+ -1.0 (/ 1.0 cosTheta)) 1.0)))
float code(float cosTheta, float c) {
	return 1.0f / fmaf(sqrtf((1.0f / ((float) M_PI))), (-1.0f + (1.0f / cosTheta)), 1.0f);
}
function code(cosTheta, c)
	return Float32(Float32(1.0) / fma(sqrt(Float32(Float32(1.0) / Float32(pi))), Float32(Float32(-1.0) + Float32(Float32(1.0) / cosTheta)), Float32(1.0)))
end
\begin{array}{l}

\\
\frac{1}{\mathsf{fma}\left(\sqrt{\frac{1}{\pi}}, -1 + \frac{1}{cosTheta}, 1\right)}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)}{cosTheta}}} \]
  6. Step-by-step derivation
    1. +-commutative94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(-1 \cdot \sqrt{\frac{1}{\pi}} + c\right)}}{cosTheta}} \]
    2. mul-1-neg94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\color{blue}{\left(-\sqrt{\frac{1}{\pi}}\right)} + c\right)}{cosTheta}} \]
  7. Simplified94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(-\sqrt{\frac{1}{\pi}}\right) + c\right)}{cosTheta}}} \]
  8. Taylor expanded in c around 0 94.4%

    \[\leadsto \color{blue}{\frac{1}{\left(1 + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right) - \sqrt{\frac{1}{\pi}}}} \]
  9. Step-by-step derivation
    1. associate--l+94.4%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} - \sqrt{\frac{1}{\pi}}\right)}} \]
    2. sub-neg94.4%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \left(-\sqrt{\frac{1}{\pi}}\right)\right)}} \]
    3. mul-1-neg94.4%

      \[\leadsto \frac{1}{1 + \left(\frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}} + \color{blue}{-1 \cdot \sqrt{\frac{1}{\pi}}}\right)} \]
    4. +-commutative94.4%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(-1 \cdot \sqrt{\frac{1}{\pi}} + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right)}} \]
    5. +-commutative94.4%

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \sqrt{\frac{1}{\pi}} + \frac{1}{cosTheta} \cdot \sqrt{\frac{1}{\pi}}\right) + 1}} \]
    6. distribute-rgt-out94.4%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(-1 + \frac{1}{cosTheta}\right)} + 1} \]
    7. fma-define94.4%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\sqrt{\frac{1}{\pi}}, -1 + \frac{1}{cosTheta}, 1\right)}} \]
  10. Simplified94.4%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{fma}\left(\sqrt{\frac{1}{\pi}}, -1 + \frac{1}{cosTheta}, 1\right)}} \]
  11. Final simplification94.4%

    \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt{\frac{1}{\pi}}, -1 + \frac{1}{cosTheta}, 1\right)} \]
  12. Add Preprocessing

Alternative 12: 92.8% accurate, 3.0× speedup?

\[\begin{array}{l} \\ cosTheta \cdot \left(\sqrt{\pi} - c \cdot \left(cosTheta \cdot \pi\right)\right) \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (* cosTheta (- (sqrt PI) (* c (* cosTheta PI)))))
float code(float cosTheta, float c) {
	return cosTheta * (sqrtf(((float) M_PI)) - (c * (cosTheta * ((float) M_PI))));
}
function code(cosTheta, c)
	return Float32(cosTheta * Float32(sqrt(Float32(pi)) - Float32(c * Float32(cosTheta * Float32(pi)))))
end
function tmp = code(cosTheta, c)
	tmp = cosTheta * (sqrt(single(pi)) - (c * (cosTheta * single(pi))));
end
\begin{array}{l}

\\
cosTheta \cdot \left(\sqrt{\pi} - c \cdot \left(cosTheta \cdot \pi\right)\right)
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in cosTheta around 0 94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)}{cosTheta}}} \]
  6. Step-by-step derivation
    1. +-commutative94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \color{blue}{\left(-1 \cdot \sqrt{\frac{1}{\pi}} + c\right)}}{cosTheta}} \]
    2. mul-1-neg94.6%

      \[\leadsto \frac{1}{1 + \frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\color{blue}{\left(-\sqrt{\frac{1}{\pi}}\right)} + c\right)}{cosTheta}} \]
  7. Simplified94.6%

    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sqrt{\frac{1}{\pi}} + cosTheta \cdot \left(\left(-\sqrt{\frac{1}{\pi}}\right) + c\right)}{cosTheta}}} \]
  8. Taylor expanded in cosTheta around 0 95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} + -1 \cdot \left(cosTheta \cdot \left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
  9. Step-by-step derivation
    1. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \color{blue}{\left(-cosTheta \cdot \left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right) \]
    2. *-commutative95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\color{blue}{\left(\pi \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right) \cdot cosTheta}\right)\right) \]
    3. sub-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \color{blue}{\left(\left(1 + c\right) + \left(-\sqrt{\frac{1}{\pi}}\right)\right)}\right) \cdot cosTheta\right)\right) \]
    4. mul-1-neg95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \left(\left(1 + c\right) + \color{blue}{-1 \cdot \sqrt{\frac{1}{\pi}}}\right)\right) \cdot cosTheta\right)\right) \]
    5. associate-+r+95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\left(\pi \cdot \color{blue}{\left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \cdot cosTheta\right)\right) \]
    6. *-commutative95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} + \left(-\color{blue}{cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right)\right) \]
    7. unsub-neg95.0%

      \[\leadsto cosTheta \cdot \color{blue}{\left(\sqrt{\pi} - cosTheta \cdot \left(\pi \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)} \]
    8. associate-*r*95.0%

      \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \color{blue}{\left(cosTheta \cdot \pi\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\pi}}\right)\right)}\right) \]
  10. Simplified95.0%

    \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\pi} - \left(\pi \cdot cosTheta\right) \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\pi}}\right)\right)} \]
  11. Taylor expanded in c around inf 91.7%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - \left(\pi \cdot cosTheta\right) \cdot \color{blue}{c}\right) \]
  12. Final simplification91.7%

    \[\leadsto cosTheta \cdot \left(\sqrt{\pi} - c \cdot \left(cosTheta \cdot \pi\right)\right) \]
  13. Add Preprocessing

Alternative 13: 92.8% accurate, 3.1× speedup?

\[\begin{array}{l} \\ cosTheta \cdot \sqrt{\pi} \end{array} \]
(FPCore (cosTheta c) :precision binary32 (* cosTheta (sqrt PI)))
float code(float cosTheta, float c) {
	return cosTheta * sqrtf(((float) M_PI));
}
function code(cosTheta, c)
	return Float32(cosTheta * sqrt(Float32(pi)))
end
function tmp = code(cosTheta, c)
	tmp = cosTheta * sqrt(single(pi));
end
\begin{array}{l}

\\
cosTheta \cdot \sqrt{\pi}
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-cube-cbrt98.0%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\color{blue}{\left(\left(\sqrt[3]{\frac{1}{\sqrt{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right)} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. cbrt-unprod98.0%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\color{blue}{\sqrt[3]{\frac{1}{\sqrt{\pi}} \cdot \frac{1}{\sqrt{\pi}}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. frac-times98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\color{blue}{\frac{1 \cdot 1}{\sqrt{\pi} \cdot \sqrt{\pi}}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. metadata-eval98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{\color{blue}{1}}{\sqrt{\pi} \cdot \sqrt{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. add-sqr-sqrt98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\color{blue}{\pi}}} \cdot \sqrt[3]{\frac{1}{\sqrt{\pi}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    6. inv-pow98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{\color{blue}{{\left(\sqrt{\pi}\right)}^{-1}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. sqrt-pow298.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{\color{blue}{{\pi}^{\left(\frac{-1}{2}\right)}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. metadata-eval98.1%

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{{\pi}^{\color{blue}{-0.5}}}\right) \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Applied egg-rr98.1%

    \[\leadsto \frac{1}{\left(1 + c\right) + \left(\color{blue}{\left(\sqrt[3]{\frac{1}{\pi}} \cdot \sqrt[3]{{\pi}^{-0.5}}\right)} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  5. Taylor expanded in cosTheta around 0 91.6%

    \[\leadsto \color{blue}{cosTheta \cdot \sqrt{\pi}} \]
  6. Final simplification91.6%

    \[\leadsto cosTheta \cdot \sqrt{\pi} \]
  7. Add Preprocessing

Alternative 14: 10.8% accurate, 322.0× speedup?

\[\begin{array}{l} \\ 1 \end{array} \]
(FPCore (cosTheta c) :precision binary32 1.0)
float code(float cosTheta, float c) {
	return 1.0f;
}
real(4) function code(costheta, c)
    real(4), intent (in) :: costheta
    real(4), intent (in) :: c
    code = 1.0e0
end function
function code(cosTheta, c)
	return Float32(1.0)
end
function tmp = code(cosTheta, c)
	tmp = single(1.0);
end
\begin{array}{l}

\\
1
\end{array}
Derivation
  1. Initial program 98.0%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Step-by-step derivation
    1. associate-+l+98.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(c + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}\right)}} \]
    2. +-commutative98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\left(\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + c\right)}} \]
    3. fma-define98.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}, e^{\left(-cosTheta\right) \cdot cosTheta}, c\right)}} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{\frac{1}{1 + \mathsf{fma}\left(\frac{\sqrt{1 + cosTheta \cdot -2}}{\sqrt{\pi} \cdot cosTheta}, {\left(e^{-cosTheta}\right)}^{cosTheta}, c\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in c around inf 10.8%

    \[\leadsto \frac{1}{1 + \color{blue}{c}} \]
  6. Taylor expanded in c around 0 10.8%

    \[\leadsto \color{blue}{1} \]
  7. Final simplification10.8%

    \[\leadsto 1 \]
  8. Add Preprocessing

Reproduce

?
herbie shell --seed 2024051 
(FPCore (cosTheta c)
  :name "Beckmann Sample, normalization factor"
  :precision binary32
  :pre (and (and (< 0.0 cosTheta) (< cosTheta 0.9999)) (and (< -1.0 c) (< c 1.0)))
  (/ 1.0 (+ (+ 1.0 c) (* (* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta)) (exp (* (- cosTheta) cosTheta))))))