\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\left(\left(\sqrt{\pi \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^{-06}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.5056327351493116 \cdot 10^{-07}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\sqrt{\pi \cdot 2} \cdot \left({\left(\left(7 - z\right) + 0.5\right)}^{\left(0.5 - z\right)} \cdot \left(700.2793595373912 \cdot \frac{z}{e^{7.5}} + \left(\frac{263.38318698105144}{e^{7.5}} + 1113.6230738897482 \cdot \frac{z \cdot z}{e^{7.5}}\right)\right)\right)\right)(FPCore (z)
:precision binary64
(*
(/ 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-06 (+ (- (- 1.0 z) 1.0) 7.0)))
(/ 1.5056327351493116e-07 (+ (- (- 1.0 z) 1.0) 8.0))))))(FPCore (z)
:precision binary64
(*
(/ PI (sin (* PI z)))
(*
(sqrt (* PI 2.0))
(*
(pow (+ (- 7.0 z) 0.5) (- 0.5 z))
(+
(* 700.2793595373912 (/ z (exp 7.5)))
(+
(/ 263.38318698105144 (exp 7.5))
(* 1113.6230738897482 (/ (* z z) (exp 7.5)))))))))double code(double z) {
return ((double) ((((double) M_PI) / ((double) sin(((double) (((double) M_PI) * z))))) * ((double) (((double) (((double) (((double) sqrt(((double) (((double) M_PI) * 2.0)))) * ((double) pow(((double) (((double) (((double) (((double) (1.0 - z)) - 1.0)) + 7.0)) + 0.5)), ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 0.5)))))) * ((double) exp(((double) -(((double) (((double) (((double) (((double) (1.0 - z)) - 1.0)) + 7.0)) + 0.5)))))))) * ((double) (((double) (((double) (((double) (((double) (((double) (((double) (((double) (0.9999999999998099 + (676.5203681218851 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 1.0))))) + (-1259.1392167224028 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 2.0))))) + (771.3234287776531 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 3.0))))) + (-176.6150291621406 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 4.0))))) + (12.507343278686905 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 5.0))))) + (-0.13857109526572012 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 6.0))))) + (9.984369578019572e-06 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 7.0))))) + (1.5056327351493116e-07 / ((double) (((double) (((double) (1.0 - z)) - 1.0)) + 8.0)))))))));
}
double code(double z) {
return ((double) ((((double) M_PI) / ((double) sin(((double) (((double) M_PI) * z))))) * ((double) (((double) sqrt(((double) (((double) M_PI) * 2.0)))) * ((double) (((double) pow(((double) (((double) (7.0 - z)) + 0.5)), ((double) (0.5 - z)))) * ((double) (((double) (700.2793595373912 * (z / ((double) exp(7.5))))) + ((double) ((263.38318698105144 / ((double) exp(7.5))) + ((double) (1113.6230738897482 * (((double) (z * z)) / ((double) exp(7.5)))))))))))))));
}



Bits error versus z
Results
Initial program 1.8
Simplified1.8
rmApplied flip3-+_binary641.8
Applied frac-add_binary641.2
Applied frac-add_binary641.2
Simplified1.2
Simplified1.2
Taylor expanded around 0 1.0
Simplified1.0
Final simplification1.0
herbie shell --seed 2020205
(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-06 (+ (- (- 1.0 z) 1.0) 7.0))) (/ 1.5056327351493116e-07 (+ (- (- 1.0 z) 1.0) 8.0))))))