Beckmann Sample, normalization factor

Percentage Accurate: 97.9% → 98.3%
Time: 9.5s
Alternatives: 10
Speedup: 1.1×

Specification

?
\[\left(0 < cosTheta \land cosTheta < 0.9999\right) \land \left(-1 < c \land c < 1\right)\]
\[\begin{array}{l} \\ \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (+ 1.0 c)
   (*
    (* (/ 1.0 (sqrt (PI))) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
    (exp (* (- cosTheta) cosTheta))))))
\begin{array}{l}

\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \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 10 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?

\[\begin{array}{l} \\ \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (+ 1.0 c)
   (*
    (* (/ 1.0 (sqrt (PI))) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
    (exp (* (- cosTheta) cosTheta))))))
\begin{array}{l}

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

Alternative 1: 98.3% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\mathsf{PI}\left(\right)}\\ t_1 := \frac{1}{c + 1}\\ \frac{1}{\frac{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{{\left(e^{cosTheta}\right)}^{cosTheta}} \cdot t\_1 + t\_0}{t\_1 \cdot t\_0}} \end{array} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (let* ((t_0 (sqrt (PI))) (t_1 (/ 1.0 (+ c 1.0))))
   (/
    1.0
    (/
     (+
      (*
       (/
        (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta)
        (pow (exp cosTheta) cosTheta))
       t_1)
      t_0)
     (* t_1 t_0)))))
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\mathsf{PI}\left(\right)}\\
t_1 := \frac{1}{c + 1}\\
\frac{1}{\frac{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{{\left(e^{cosTheta}\right)}^{cosTheta}} \cdot t\_1 + t\_0}{t\_1 \cdot t\_0}}
\end{array}
\end{array}
Derivation
  1. Initial program 98.1%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f32N/A

      \[\leadsto \frac{1}{\color{blue}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}} \]
    2. lift-+.f32N/A

      \[\leadsto \frac{1}{\color{blue}{\left(1 + c\right)} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. flip3-+N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{{1}^{3} + {c}^{3}}{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. clear-numN/A

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}}} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. lift-*.f32N/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}} \]
    6. lift-*.f32N/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. *-commutativeN/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \frac{1}{\sqrt{\mathsf{PI}\left(\right)}}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. lift-/.f32N/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}}}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    9. div-invN/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    10. associate-*l/N/A

      \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}}} \]
  4. Applied rewrites98.6%

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

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

Alternative 2: 98.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{e^{\left(-cosTheta\right) \cdot cosTheta} \cdot \frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}} + \left(c + 1\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (*
    (exp (* (- cosTheta) cosTheta))
    (/ (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta) (sqrt (PI))))
   (+ c 1.0))))
\begin{array}{l}

\\
\frac{1}{e^{\left(-cosTheta\right) \cdot cosTheta} \cdot \frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}} + \left(c + 1\right)}
\end{array}
Derivation
  1. Initial program 98.1%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \frac{1}{\sqrt{\mathsf{PI}\left(\right)}}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. lift-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}}}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. div-invN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. lower-/.f3298.6

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Applied rewrites98.6%

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

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

Alternative 3: 98.5% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (*
    (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) (* cosTheta (sqrt (PI))))
    (exp (* (- cosTheta) cosTheta)))
   (+ c 1.0))))
\begin{array}{l}

\\
\frac{1}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)}
\end{array}
Derivation
  1. Initial program 98.1%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. lift-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. lift-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. frac-timesN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{1 \cdot \sqrt{\left(1 - cosTheta\right) - cosTheta}}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. *-lft-identityN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\left(1 - cosTheta\right) - cosTheta}}}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    6. lower-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. *-commutativeN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{\color{blue}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. lower-*.f3298.5

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{\color{blue}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Applied rewrites98.5%

    \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  5. Final simplification98.5%

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

Alternative 4: 98.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{\sqrt{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (*
    (/ (sqrt (/ (- (- 1.0 cosTheta) cosTheta) (PI))) cosTheta)
    (exp (* (- cosTheta) cosTheta)))
   (+ c 1.0))))
\begin{array}{l}

\\
\frac{1}{\frac{\sqrt{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)}
\end{array}
Derivation
  1. Initial program 98.1%

    \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. lift-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \color{blue}{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. associate-*r/N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. lower-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. lift-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot \sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    6. associate-*l/N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\frac{1 \cdot \sqrt{\left(1 - cosTheta\right) - cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. *-lft-identityN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\frac{\color{blue}{\sqrt{\left(1 - cosTheta\right) - cosTheta}}}{\sqrt{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. lift-sqrt.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\frac{\color{blue}{\sqrt{\left(1 - cosTheta\right) - cosTheta}}}{\sqrt{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    9. lift-sqrt.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{\color{blue}{\sqrt{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    10. sqrt-undivN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    11. lower-sqrt.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    12. lower-/.f3297.9

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\color{blue}{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Applied rewrites97.9%

    \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{\left(1 - cosTheta\right) - cosTheta}{\mathsf{PI}\left(\right)}}}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  5. Final simplification97.9%

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

Alternative 5: 95.9% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \end{array} \]
(FPCore (cosTheta c)
 :precision binary32
 (/
  1.0
  (+
   (*
    (/ (/ (- 1.0 cosTheta) cosTheta) (sqrt (PI)))
    (exp (* (- cosTheta) cosTheta)))
   (+ c 1.0))))
\begin{array}{l}

\\
\frac{1}{\frac{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)}
\end{array}
Derivation
  1. Initial program 98.1%

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

    \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  4. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \color{blue}{\left(-1 \cdot cosTheta\right) \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. lower-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \left(-1 \cdot cosTheta\right) \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    3. mul-1-negN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \color{blue}{\left(\mathsf{neg}\left(cosTheta\right)\right)} \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    4. cancel-sign-sub-invN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} - cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    5. *-lft-identityN/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{1 \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}} - cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    6. distribute-rgt-out--N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    7. lower-*.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    8. lower-sqrt.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    9. lower-/.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\color{blue}{\frac{1}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    10. lower-PI.f32N/A

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\color{blue}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    11. lower--.f3295.9

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \color{blue}{\left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  5. Applied rewrites95.9%

    \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
  6. Step-by-step derivation
    1. Applied rewrites96.7%

      \[\leadsto \frac{1}{\left(1 + c\right) + \frac{1 \cdot \left(1 - cosTheta\right)}{\color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
    2. Step-by-step derivation
      1. Applied rewrites96.7%

        \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
      2. Final simplification96.7%

        \[\leadsto \frac{1}{\frac{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \]
      3. Add Preprocessing

      Alternative 6: 96.0% accurate, 1.2× speedup?

      \[\begin{array}{l} \\ \frac{1}{\frac{1 - cosTheta}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \end{array} \]
      (FPCore (cosTheta c)
       :precision binary32
       (/
        1.0
        (+
         (*
          (/ (- 1.0 cosTheta) (* cosTheta (sqrt (PI))))
          (exp (* (- cosTheta) cosTheta)))
         (+ c 1.0))))
      \begin{array}{l}
      
      \\
      \frac{1}{\frac{1 - cosTheta}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)}
      \end{array}
      
      Derivation
      1. Initial program 98.1%

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

        \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + -1 \cdot \left(cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
      4. Step-by-step derivation
        1. associate-*r*N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \color{blue}{\left(-1 \cdot cosTheta\right) \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        2. lower-/.f32N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \left(-1 \cdot cosTheta\right) \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        3. mul-1-negN/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} + \color{blue}{\left(\mathsf{neg}\left(cosTheta\right)\right)} \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        4. cancel-sign-sub-invN/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} - cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        5. *-lft-identityN/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{1 \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}} - cosTheta \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        6. distribute-rgt-out--N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        7. lower-*.f32N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        8. lower-sqrt.f32N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\color{blue}{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        9. lower-/.f32N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\color{blue}{\frac{1}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        10. lower-PI.f32N/A

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\color{blue}{\mathsf{PI}\left(\right)}}} \cdot \left(1 - cosTheta\right)}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        11. lower--.f3295.9

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \color{blue}{\left(1 - cosTheta\right)}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
      5. Applied rewrites95.9%

        \[\leadsto \frac{1}{\left(1 + c\right) + \color{blue}{\frac{\sqrt{\frac{1}{\mathsf{PI}\left(\right)}} \cdot \left(1 - cosTheta\right)}{cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
      6. Step-by-step derivation
        1. Applied rewrites96.7%

          \[\leadsto \frac{1}{\left(1 + c\right) + \frac{1 \cdot \left(1 - cosTheta\right)}{\color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
        2. Step-by-step derivation
          1. Applied rewrites96.7%

            \[\leadsto \frac{1}{\left(1 + c\right) + \frac{1 - cosTheta}{\color{blue}{\sqrt{\mathsf{PI}\left(\right)}} \cdot cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
          2. Final simplification96.7%

            \[\leadsto \frac{1}{\frac{1 - cosTheta}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta} + \left(c + 1\right)} \]
          3. Add Preprocessing

          Alternative 7: 95.7% accurate, 3.3× speedup?

          \[\begin{array}{l} \\ \left(\sqrt{\mathsf{PI}\left(\right)} - \left(\left(c + 1\right) - \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right) \cdot \left(cosTheta \cdot \mathsf{PI}\left(\right)\right)\right) \cdot cosTheta \end{array} \]
          (FPCore (cosTheta c)
           :precision binary32
           (*
            (- (sqrt (PI)) (* (- (+ c 1.0) (sqrt (/ 1.0 (PI)))) (* cosTheta (PI))))
            cosTheta))
          \begin{array}{l}
          
          \\
          \left(\sqrt{\mathsf{PI}\left(\right)} - \left(\left(c + 1\right) - \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right) \cdot \left(cosTheta \cdot \mathsf{PI}\left(\right)\right)\right) \cdot cosTheta
          \end{array}
          
          Derivation
          1. Initial program 98.1%

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

            \[\leadsto \color{blue}{\frac{1}{c}} \]
          4. Step-by-step derivation
            1. lower-/.f325.0

              \[\leadsto \color{blue}{\frac{1}{c}} \]
          5. Applied rewrites5.0%

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

            \[\leadsto \color{blue}{cosTheta \cdot \left(\sqrt{\mathsf{PI}\left(\right)} + -1 \cdot \left(cosTheta \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)\right)\right)\right)\right)} \]
          7. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \color{blue}{\left(\sqrt{\mathsf{PI}\left(\right)} + -1 \cdot \left(cosTheta \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)\right)\right)\right)\right) \cdot cosTheta} \]
            2. lower-*.f32N/A

              \[\leadsto \color{blue}{\left(\sqrt{\mathsf{PI}\left(\right)} + -1 \cdot \left(cosTheta \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 + \left(c + -1 \cdot \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)\right)\right)\right)\right) \cdot cosTheta} \]
          8. Applied rewrites96.6%

            \[\leadsto \color{blue}{\left(\sqrt{\mathsf{PI}\left(\right)} - \left(\mathsf{PI}\left(\right) \cdot cosTheta\right) \cdot \left(\left(1 + c\right) - \sqrt{\frac{1}{\mathsf{PI}\left(\right)}}\right)\right) \cdot cosTheta} \]
          9. Final simplification96.6%

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

          Alternative 8: 92.8% accurate, 4.8× speedup?

          \[\begin{array}{l} \\ \frac{\left(\left(c + 1\right) \cdot cosTheta\right) \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \end{array} \]
          (FPCore (cosTheta c)
           :precision binary32
           (/ (* (* (+ c 1.0) cosTheta) (sqrt (PI))) (+ c 1.0)))
          \begin{array}{l}
          
          \\
          \frac{\left(\left(c + 1\right) \cdot cosTheta\right) \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1}
          \end{array}
          
          Derivation
          1. Initial program 98.1%

            \[\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-+.f32N/A

              \[\leadsto \frac{1}{\color{blue}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}} \]
            2. lift-+.f32N/A

              \[\leadsto \frac{1}{\color{blue}{\left(1 + c\right)} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            3. flip3-+N/A

              \[\leadsto \frac{1}{\color{blue}{\frac{{1}^{3} + {c}^{3}}{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            4. clear-numN/A

              \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}}} + \left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            5. lift-*.f32N/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}} \]
            6. lift-*.f32N/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{1}{\sqrt{\mathsf{PI}\left(\right)}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            7. *-commutativeN/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \frac{1}{\sqrt{\mathsf{PI}\left(\right)}}\right)} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            8. lift-/.f32N/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \left(\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot \color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)}}}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            9. div-invN/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}} \]
            10. associate-*l/N/A

              \[\leadsto \frac{1}{\frac{1}{\frac{1 \cdot 1 + \left(c \cdot c - 1 \cdot c\right)}{{1}^{3} + {c}^{3}}} + \color{blue}{\frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta} \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}{\sqrt{\mathsf{PI}\left(\right)}}}} \]
          4. Applied rewrites98.6%

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

            \[\leadsto \frac{1}{\frac{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \color{blue}{\frac{1}{cosTheta}}}{\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}}} \]
          6. Step-by-step derivation
            1. lower-/.f3293.8

              \[\leadsto \frac{1}{\frac{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \color{blue}{\frac{1}{cosTheta}}}{\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}}} \]
          7. Applied rewrites93.8%

            \[\leadsto \frac{1}{\frac{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \color{blue}{\frac{1}{cosTheta}}}{\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}}} \]
          8. Step-by-step derivation
            1. lift-/.f32N/A

              \[\leadsto \color{blue}{\frac{1}{\frac{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}}{\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}}}} \]
            2. lift-/.f32N/A

              \[\leadsto \frac{1}{\color{blue}{\frac{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}}{\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}}}} \]
            3. associate-/r/N/A

              \[\leadsto \color{blue}{\frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \left(\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}\right)} \]
            4. lift-*.f32N/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \color{blue}{\left(\frac{1}{c + 1} \cdot \sqrt{\mathsf{PI}\left(\right)}\right)} \]
            5. *-commutativeN/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \color{blue}{\left(\sqrt{\mathsf{PI}\left(\right)} \cdot \frac{1}{c + 1}\right)} \]
            6. lift-/.f32N/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \color{blue}{\frac{1}{c + 1}}\right) \]
            7. lift-+.f32N/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \frac{1}{\color{blue}{c + 1}}\right) \]
            8. +-commutativeN/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \frac{1}{\color{blue}{1 + c}}\right) \]
            9. lift-+.f32N/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \frac{1}{\color{blue}{1 + c}}\right) \]
            10. div-invN/A

              \[\leadsto \frac{1}{\sqrt{\mathsf{PI}\left(\right)} + \frac{1}{c + 1} \cdot \frac{1}{cosTheta}} \cdot \color{blue}{\frac{\sqrt{\mathsf{PI}\left(\right)}}{1 + c}} \]
          9. Applied rewrites93.8%

            \[\leadsto \color{blue}{\frac{\frac{1}{\frac{\frac{1}{cosTheta}}{c + 1} + \sqrt{\mathsf{PI}\left(\right)}} \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1}} \]
          10. Taylor expanded in cosTheta around 0

            \[\leadsto \frac{\color{blue}{\left(cosTheta \cdot \left(1 + c\right)\right)} \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
          11. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \frac{\color{blue}{\left(\left(1 + c\right) \cdot cosTheta\right)} \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
            2. lower-*.f32N/A

              \[\leadsto \frac{\color{blue}{\left(\left(1 + c\right) \cdot cosTheta\right)} \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
            3. lower-+.f3294.2

              \[\leadsto \frac{\left(\color{blue}{\left(1 + c\right)} \cdot cosTheta\right) \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
          12. Applied rewrites94.2%

            \[\leadsto \frac{\color{blue}{\left(\left(1 + c\right) \cdot cosTheta\right)} \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
          13. Final simplification94.2%

            \[\leadsto \frac{\left(\left(c + 1\right) \cdot cosTheta\right) \cdot \sqrt{\mathsf{PI}\left(\right)}}{c + 1} \]
          14. Add Preprocessing

          Alternative 9: 92.9% accurate, 11.4× speedup?

          \[\begin{array}{l} \\ cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)} \end{array} \]
          (FPCore (cosTheta c) :precision binary32 (* cosTheta (sqrt (PI))))
          \begin{array}{l}
          
          \\
          cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}
          \end{array}
          
          Derivation
          1. Initial program 98.1%

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

            \[\leadsto \color{blue}{cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)}} \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta} \]
            2. lower-*.f32N/A

              \[\leadsto \color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta} \]
            3. lower-sqrt.f32N/A

              \[\leadsto \color{blue}{\sqrt{\mathsf{PI}\left(\right)}} \cdot cosTheta \]
            4. lower-PI.f3294.2

              \[\leadsto \sqrt{\color{blue}{\mathsf{PI}\left(\right)}} \cdot cosTheta \]
          5. Applied rewrites94.2%

            \[\leadsto \color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot cosTheta} \]
          6. Final simplification94.2%

            \[\leadsto cosTheta \cdot \sqrt{\mathsf{PI}\left(\right)} \]
          7. Add Preprocessing

          Alternative 10: 5.0% accurate, 15.3× speedup?

          \[\begin{array}{l} \\ \frac{1}{c} \end{array} \]
          (FPCore (cosTheta c) :precision binary32 (/ 1.0 c))
          float code(float cosTheta, float c) {
          	return 1.0f / c;
          }
          
          real(4) function code(costheta, c)
              real(4), intent (in) :: costheta
              real(4), intent (in) :: c
              code = 1.0e0 / c
          end function
          
          function code(cosTheta, c)
          	return Float32(Float32(1.0) / c)
          end
          
          function tmp = code(cosTheta, c)
          	tmp = single(1.0) / c;
          end
          
          \begin{array}{l}
          
          \\
          \frac{1}{c}
          \end{array}
          
          Derivation
          1. Initial program 98.1%

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

            \[\leadsto \color{blue}{\frac{1}{c}} \]
          4. Step-by-step derivation
            1. lower-/.f325.0

              \[\leadsto \color{blue}{\frac{1}{c}} \]
          5. Applied rewrites5.0%

            \[\leadsto \color{blue}{\frac{1}{c}} \]
          6. Add Preprocessing

          Reproduce

          ?
          herbie shell --seed 2024295 
          (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))))))