
(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:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(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}
(FPCore (z)
:precision binary64
(*
(/ (PI) (sin (* (PI) z)))
(*
(*
(*
(* (sqrt (PI)) (sqrt 2.0))
(pow (+ (+ (- (- 1.0 z) 1.0) 7.0) 0.5) (+ (- 1.0 (+ z 1.0)) 0.5)))
(exp (- z 7.5)))
(+ 263.3831869810514 (* z (+ 436.8961725563396 (* 545.0353078428827 z)))))))\begin{array}{l}
\\
\frac{\mathsf{PI}\left(\right)}{\sin \left(\mathsf{PI}\left(\right) \cdot z\right)} \cdot \left(\left(\left(\left(\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2}\right) \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(1 - \left(z + 1\right)\right) + 0.5\right)}\right) \cdot e^{z - 7.5}\right) \cdot \left(263.3831869810514 + z \cdot \left(436.8961725563396 + 545.0353078428827 \cdot z\right)\right)\right)
\end{array}
Initial program 96.6%
Taylor expanded in z around 0
lower-+.f64N/A
lower-*.f64N/A
lower-+.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
lift-sqrt.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
sqrt-prodN/A
lower-*.f64N/A
lift-sqrt.f64N/A
lift-PI.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
lift--.f64N/A
lift--.f64N/A
associate--l-N/A
lower--.f64N/A
lower-+.f6498.5
Applied rewrites98.5%
Taylor expanded in z around 0
lower--.f6498.5
Applied rewrites98.5%
(FPCore (z)
:precision binary64
(let* ((t_0 (- (- 1.0 z) 1.0)) (t_1 (+ (+ t_0 7.0) 0.5)))
(*
(pow z -1.0)
(*
(* (* (* (sqrt (PI)) (sqrt 2.0)) (pow t_1 (+ t_0 0.5))) (exp (- t_1)))
(+
263.3831869810514
(* z (+ 436.8961725563396 (* 545.0353078428827 z))))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - z\right) - 1\\
t_1 := \left(t\_0 + 7\right) + 0.5\\
{z}^{-1} \cdot \left(\left(\left(\left(\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2}\right) \cdot {t\_1}^{\left(t\_0 + 0.5\right)}\right) \cdot e^{-t\_1}\right) \cdot \left(263.3831869810514 + z \cdot \left(436.8961725563396 + 545.0353078428827 \cdot z\right)\right)\right)
\end{array}
\end{array}
Initial program 96.6%
Taylor expanded in z around 0
lower-+.f64N/A
lower-*.f64N/A
lower-+.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
lift-sqrt.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
sqrt-prodN/A
lower-*.f64N/A
lift-sqrt.f64N/A
lift-PI.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
Taylor expanded in z around 0
inv-powN/A
lower-pow.f6498.5
Applied rewrites98.5%
(FPCore (z)
:precision binary64
(let* ((t_0 (+ (+ (- (- 1.0 z) 1.0) 7.0) 0.5)))
(*
(/ (PI) (* (PI) z))
(*
(*
(* (* (sqrt (PI)) (sqrt 2.0)) (pow t_0 (+ (- 1.0 (+ z 1.0)) 0.5)))
(exp (- t_0)))
(+
263.3831869810514
(* z (+ 436.8961725563396 (* 545.0353078428827 z))))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\\
\frac{\mathsf{PI}\left(\right)}{\mathsf{PI}\left(\right) \cdot z} \cdot \left(\left(\left(\left(\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2}\right) \cdot {t\_0}^{\left(\left(1 - \left(z + 1\right)\right) + 0.5\right)}\right) \cdot e^{-t\_0}\right) \cdot \left(263.3831869810514 + z \cdot \left(436.8961725563396 + 545.0353078428827 \cdot z\right)\right)\right)
\end{array}
\end{array}
Initial program 96.6%
Taylor expanded in z around 0
lower-+.f64N/A
lower-*.f64N/A
lower-+.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
lift-sqrt.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
sqrt-prodN/A
lower-*.f64N/A
lift-sqrt.f64N/A
lift-PI.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
lift--.f64N/A
lift--.f64N/A
associate--l-N/A
lower--.f64N/A
lower-+.f6498.5
Applied rewrites98.5%
Taylor expanded in z around 0
*-commutativeN/A
lift-*.f64N/A
lift-PI.f6498.3
Applied rewrites98.3%
(FPCore (z) :precision binary64 (* 263.3831869810514 (/ (* (* (sqrt (PI)) (exp -7.5)) (sqrt 15.0)) z)))
\begin{array}{l}
\\
263.3831869810514 \cdot \frac{\left(\sqrt{\mathsf{PI}\left(\right)} \cdot e^{-7.5}\right) \cdot \sqrt{15}}{z}
\end{array}
Initial program 96.6%
Taylor expanded in z around 0
lower-+.f64N/A
lower-*.f64N/A
lower-+.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
Taylor expanded in z around 0
sqrt-unprodN/A
metadata-evalN/A
Applied rewrites97.3%
lift-*.f64N/A
lift-/.f64N/A
lift-PI.f64N/A
lift-sqrt.f64N/A
associate-*l/N/A
lift-*.f64N/A
lift-exp.f64N/A
lift-sqrt.f64N/A
metadata-evalN/A
sqrt-unprodN/A
*-commutativeN/A
lower-/.f64N/A
Applied rewrites97.2%
lift-*.f64N/A
lift-PI.f64N/A
lift-sqrt.f64N/A
*-commutativeN/A
lift-*.f64N/A
lift-exp.f64N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
lift-sqrt.f64N/A
lift-PI.f64N/A
lift-exp.f6497.9
Applied rewrites97.9%
(FPCore (z) :precision binary64 (* 263.3831869810514 (* (/ (* (exp -7.5) (sqrt 15.0)) z) (sqrt (PI)))))
\begin{array}{l}
\\
263.3831869810514 \cdot \left(\frac{e^{-7.5} \cdot \sqrt{15}}{z} \cdot \sqrt{\mathsf{PI}\left(\right)}\right)
\end{array}
Initial program 96.6%
Taylor expanded in z around 0
lower-+.f64N/A
lower-*.f64N/A
lower-+.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
Taylor expanded in z around 0
sqrt-unprodN/A
metadata-evalN/A
Applied rewrites97.3%
herbie shell --seed 2025028
(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))))))