Jmat.Real.gamma, branch z less than 0.5

Percentage Accurate: 96.4% → 96.4%
Time: 11.2s
Alternatives: 5
Speedup: 1.0×

Specification

?
\[z \leq 0.5\]
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(1 - z\right) - 1\\ t_1 := t\_0 + 7\\ t_2 := t\_1 + 0.5\\ \frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right) \end{array} \end{array} \]
(FPCore (z)
 :precision binary64
 (let* ((t_0 (- (- 1.0 z) 1.0)) (t_1 (+ t_0 7.0)) (t_2 (+ t_1 0.5)))
   (*
    (/ (PI) (sin (* (PI) z)))
    (*
     (* (* (sqrt (* (PI) 2.0)) (pow t_2 (+ t_0 0.5))) (exp (- t_2)))
     (+
      (+
       (+
        (+
         (+
          (+
           (+
            (+ 0.9999999999998099 (/ 676.5203681218851 (+ t_0 1.0)))
            (/ -1259.1392167224028 (+ t_0 2.0)))
           (/ 771.3234287776531 (+ t_0 3.0)))
          (/ -176.6150291621406 (+ t_0 4.0)))
         (/ 12.507343278686905 (+ t_0 5.0)))
        (/ -0.13857109526572012 (+ t_0 6.0)))
       (/ 9.984369578019572e-6 t_1))
      (/ 1.5056327351493116e-7 (+ t_0 8.0)))))))
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(1 - z\right) - 1\\
t_1 := t\_0 + 7\\
t_2 := t\_1 + 0.5\\
\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right)
\end{array}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 5 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: 96.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(1 - z\right) - 1\\ t_1 := t\_0 + 7\\ t_2 := t\_1 + 0.5\\ \frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right) \end{array} \end{array} \]
(FPCore (z)
 :precision binary64
 (let* ((t_0 (- (- 1.0 z) 1.0)) (t_1 (+ t_0 7.0)) (t_2 (+ t_1 0.5)))
   (*
    (/ (PI) (sin (* (PI) z)))
    (*
     (* (* (sqrt (* (PI) 2.0)) (pow t_2 (+ t_0 0.5))) (exp (- t_2)))
     (+
      (+
       (+
        (+
         (+
          (+
           (+
            (+ 0.9999999999998099 (/ 676.5203681218851 (+ t_0 1.0)))
            (/ -1259.1392167224028 (+ t_0 2.0)))
           (/ 771.3234287776531 (+ t_0 3.0)))
          (/ -176.6150291621406 (+ t_0 4.0)))
         (/ 12.507343278686905 (+ t_0 5.0)))
        (/ -0.13857109526572012 (+ t_0 6.0)))
       (/ 9.984369578019572e-6 t_1))
      (/ 1.5056327351493116e-7 (+ t_0 8.0)))))))
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(1 - z\right) - 1\\
t_1 := t\_0 + 7\\
t_2 := t\_1 + 0.5\\
\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right)
\end{array}
\end{array}

Alternative 1: 96.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(1 - z\right) - 1\\ t_1 := t\_0 + 7\\ t_2 := t\_1 + 0.5\\ \frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right) \end{array} \end{array} \]
(FPCore (z)
 :precision binary64
 (let* ((t_0 (- (- 1.0 z) 1.0)) (t_1 (+ t_0 7.0)) (t_2 (+ t_1 0.5)))
   (*
    (/ (PI) (sin (* (PI) z)))
    (*
     (* (* (sqrt (* (PI) 2.0)) (pow t_2 (+ t_0 0.5))) (exp (- t_2)))
     (+
      (+
       (+
        (+
         (+
          (+
           (+
            (+ 0.9999999999998099 (/ 676.5203681218851 (+ t_0 1.0)))
            (/ -1259.1392167224028 (+ t_0 2.0)))
           (/ 771.3234287776531 (+ t_0 3.0)))
          (/ -176.6150291621406 (+ t_0 4.0)))
         (/ 12.507343278686905 (+ t_0 5.0)))
        (/ -0.13857109526572012 (+ t_0 6.0)))
       (/ 9.984369578019572e-6 t_1))
      (/ 1.5056327351493116e-7 (+ t_0 8.0)))))))
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(1 - z\right) - 1\\
t_1 := t\_0 + 7\\
t_2 := t\_1 + 0.5\\
\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {t\_2}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_2}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{t\_0 + 1}\right) + \frac{-1259.1392167224028}{t\_0 + 2}\right) + \frac{771.3234287776531}{t\_0 + 3}\right) + \frac{-176.6150291621406}{t\_0 + 4}\right) + \frac{12.507343278686905}{t\_0 + 5}\right) + \frac{-0.13857109526572012}{t\_0 + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{t\_1}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{t\_0 + 8}\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 96.2%

    \[\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.1392167224028}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621406}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.507343278686905}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.13857109526572012}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right) \]
  2. Add Preprocessing
  3. Add Preprocessing

Alternative 2: 95.4% accurate, 4.9× speedup?

\[\begin{array}{l} \\ \frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \end{array} \]
(FPCore (z) :precision binary64 (/ (PI) (sin (* (PI) z))))
\begin{array}{l}

\\
\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)}
\end{array}
Derivation
  1. Initial program 96.2%

    \[\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.1392167224028}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621406}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.507343278686905}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.13857109526572012}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right) \]
  2. Add Preprocessing
  3. Taylor expanded in z around 0

    \[\leadsto \color{blue}{\frac{\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right) + \left(z \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right) \cdot \sqrt{{\mathsf{PI}\left(\right)}^{3}}}{z}} \]
  4. Applied rewrites95.4%

    \[\leadsto \color{blue}{\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)}} \]
  5. Add Preprocessing

Alternative 3: 95.4% accurate, 33.6× speedup?

\[\begin{array}{l} \\ \frac{\mathsf{PI}\left(\right)}{\mathsf{PI}\left(\right) \cdot z} \end{array} \]
(FPCore (z) :precision binary64 (/ (PI) (* (PI) z)))
\begin{array}{l}

\\
\frac{\mathsf{PI}\left(\right)}{\mathsf{PI}\left(\right) \cdot z}
\end{array}
Derivation
  1. Initial program 96.2%

    \[\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.1392167224028}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621406}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.507343278686905}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.13857109526572012}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right) \]
  2. Add Preprocessing
  3. Taylor expanded in z around 0

    \[\leadsto \color{blue}{\frac{\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right) + \left(z \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right) \cdot \sqrt{{\mathsf{PI}\left(\right)}^{3}}}{z}} \]
  4. Applied rewrites95.4%

    \[\leadsto \color{blue}{\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)}} \]
  5. Taylor expanded in z around 0

    \[\leadsto \frac{\mathsf{PI}\left(\right)}{z \cdot \color{blue}{\mathsf{PI}\left(\right)}} \]
  6. Applied rewrites95.3%

    \[\leadsto \frac{\mathsf{PI}\left(\right)}{\mathsf{PI}\left(\right) \cdot \color{blue}{z}} \]
  7. Add Preprocessing

Alternative 4: 3.8% accurate, 95.3× speedup?

\[\begin{array}{l} \\ \mathsf{PI}\left(\right) \cdot z \end{array} \]
(FPCore (z) :precision binary64 (* (PI) z))
\begin{array}{l}

\\
\mathsf{PI}\left(\right) \cdot z
\end{array}
Derivation
  1. Initial program 96.2%

    \[\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.1392167224028}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621406}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.507343278686905}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.13857109526572012}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right) \]
  2. Add Preprocessing
  3. Taylor expanded in z around 0

    \[\leadsto \color{blue}{\frac{\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right) + z \cdot \left(z \cdot \left(\sqrt{{\mathsf{PI}\left(\right)}^{3}} \cdot \left(\left(\frac{1106209385320415913103082059}{8400000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \left(\frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(\frac{29}{225} + \frac{1}{2} \cdot {\left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)}^{2}\right)\right) + \left(\frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{64608921419941589693928044520019}{118540800000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right) - \frac{-1106209385320415913103082059}{25200000000000000000000000} \cdot \left(\mathsf{PI}\left(\right) \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)\right) + \left(z \cdot \left(\left(\frac{1}{2} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)} + \left(\frac{1106209385320415913103082059}{25200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \left(\frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(\frac{86}{10125} + \left(\frac{29}{225} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right) + \frac{1}{6} \cdot {\left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)}^{3}\right)\right)\right) + \left(\frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(\frac{29}{225} + \frac{1}{2} \cdot {\left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)}^{2}\right)\right) + \left(\frac{64608921419941589693928044520019}{118540800000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{4027292589444183035165374538123333}{6638284800000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(\frac{29}{225} + \frac{1}{2} \cdot {\left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)}^{2}\right)\right) + \left(\frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{64608921419941589693928044520019}{118540800000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)}{\mathsf{PI}\left(\right)}\right)\right)\right) - \frac{-1}{6} \cdot \left({\mathsf{PI}\left(\right)}^{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right)\right)\right) \cdot \sqrt{{\mathsf{PI}\left(\right)}^{3}}\right) + \sqrt{{\mathsf{PI}\left(\right)}^{3}} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right)}{z}} \]
  4. Applied rewrites3.8%

    \[\leadsto \color{blue}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \]
  5. Taylor expanded in z around 0

    \[\leadsto z \cdot \color{blue}{\mathsf{PI}\left(\right)} \]
  6. Applied rewrites3.7%

    \[\leadsto \mathsf{PI}\left(\right) \cdot \color{blue}{z} \]
  7. Add Preprocessing

Alternative 5: 3.2% accurate, 572.0× speedup?

\[\begin{array}{l} \\ \mathsf{PI}\left(\right) \end{array} \]
(FPCore (z) :precision binary64 (PI))
\begin{array}{l}

\\
\mathsf{PI}\left(\right)
\end{array}
Derivation
  1. Initial program 96.2%

    \[\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\sqrt{\mathsf{PI}\left(\right) \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099 + \frac{676.5203681218851}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.1392167224028}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621406}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.507343278686905}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.13857109526572012}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019572 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right) \]
  2. Add Preprocessing
  3. Taylor expanded in z around 0

    \[\leadsto \color{blue}{\frac{\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\mathsf{PI}\left(\right)} \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right) + z \cdot \left(\sqrt{{\mathsf{PI}\left(\right)}^{3}} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right) + \left(z \cdot \left(\left(\frac{1106209385320415913103082059}{8400000000000000000000000} \cdot \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)}{\mathsf{PI}\left(\right)} + \left(\frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(\frac{29}{225} + \frac{1}{2} \cdot {\left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)}^{2}\right)\right) + \left(\frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{64608921419941589693928044520019}{118540800000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)}{\mathsf{PI}\left(\right)} + \frac{e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \left(\frac{1106209385320415913103082059}{4200000000000000000000000} \cdot \left(\sqrt{\frac{15}{2}} \cdot \left(-1 \cdot \log \frac{15}{2} - \frac{1}{15}\right)\right) + \frac{102757979785251069442117317613}{235200000000000000000000000} \cdot \sqrt{\frac{15}{2}}\right)\right)}{\mathsf{PI}\left(\right)}\right)\right) - \frac{-1106209385320415913103082059}{25200000000000000000000000} \cdot \left(\mathsf{PI}\left(\right) \cdot \left(e^{\frac{-15}{2}} \cdot \left(\sqrt{2} \cdot \sqrt{\frac{15}{2}}\right)\right)\right)\right)\right) \cdot \sqrt{{\mathsf{PI}\left(\right)}^{3}}\right)}{z}} \]
  4. Applied rewrites3.0%

    \[\leadsto \color{blue}{\mathsf{PI}\left(\right)} \]
  5. Add Preprocessing

Reproduce

?
herbie shell --seed 2024313 
(FPCore (z)
  :name "Jmat.Real.gamma, branch z less than 0.5"
  :precision binary64
  :pre (<= z 0.5)
  (* (/ (PI) (sin (* (PI) z))) (* (* (* (sqrt (* (PI) 2.0)) (pow (+ (+ (- (- 1.0 z) 1.0) 7.0) 0.5) (+ (- (- 1.0 z) 1.0) 0.5))) (exp (- (+ (+ (- (- 1.0 z) 1.0) 7.0) 0.5)))) (+ (+ (+ (+ (+ (+ (+ (+ 0.9999999999998099 (/ 676.5203681218851 (+ (- (- 1.0 z) 1.0) 1.0))) (/ -1259.1392167224028 (+ (- (- 1.0 z) 1.0) 2.0))) (/ 771.3234287776531 (+ (- (- 1.0 z) 1.0) 3.0))) (/ -176.6150291621406 (+ (- (- 1.0 z) 1.0) 4.0))) (/ 12.507343278686905 (+ (- (- 1.0 z) 1.0) 5.0))) (/ -0.13857109526572012 (+ (- (- 1.0 z) 1.0) 6.0))) (/ 9.984369578019572e-6 (+ (- (- 1.0 z) 1.0) 7.0))) (/ 1.5056327351493116e-7 (+ (- (- 1.0 z) 1.0) 8.0))))))