x + \frac{y \cdot \left(\left(z \cdot 0.0692910599291889 + 0.4917317610505968\right) \cdot z + 0.279195317918525\right)}{\left(z + 6.012459259764103\right) \cdot z + 3.350343815022304}\begin{array}{l}
\mathbf{if}\;z \leq -9.990746456204017 \cdot 10^{+35} \lor \neg \left(z \leq 48.17602907496802\right):\\
\;\;\;\;x + y \cdot 0.0692910599291889\\
\mathbf{else}:\\
\;\;\;\;x + \frac{y \cdot \left(z \cdot \left(z \cdot 0.0692910599291889 + 0.4917317610505968\right) + 0.279195317918525\right)}{z \cdot \left(z + 6.012459259764103\right) + 3.350343815022304}\\
\end{array}(FPCore (x y z)
:precision binary64
(+
x
(/
(*
y
(+
(* (+ (* z 0.0692910599291889) 0.4917317610505968) z)
0.279195317918525))
(+ (* (+ z 6.012459259764103) z) 3.350343815022304))))(FPCore (x y z)
:precision binary64
(if (or (<= z -9.990746456204017e+35) (not (<= z 48.17602907496802)))
(+ x (* y 0.0692910599291889))
(+
x
(/
(*
y
(+
(* z (+ (* z 0.0692910599291889) 0.4917317610505968))
0.279195317918525))
(+ (* z (+ z 6.012459259764103)) 3.350343815022304)))))double code(double x, double y, double z) {
return x + ((y * ((((z * 0.0692910599291889) + 0.4917317610505968) * z) + 0.279195317918525)) / (((z + 6.012459259764103) * z) + 3.350343815022304));
}
double code(double x, double y, double z) {
double tmp;
if ((z <= -9.990746456204017e+35) || !(z <= 48.17602907496802)) {
tmp = x + (y * 0.0692910599291889);
} else {
tmp = x + ((y * ((z * ((z * 0.0692910599291889) + 0.4917317610505968)) + 0.279195317918525)) / ((z * (z + 6.012459259764103)) + 3.350343815022304));
}
return tmp;
}












Bits error versus x












Bits error versus y












Bits error versus z
Results
| Original | 19.7 |
|---|---|
| Target | 0.2 |
| Herbie | 0.3 |
| Alternative 1 | |
|---|---|
| Error | 0.5 |
| Cost | 1281 |
| Alternative 2 | |
|---|---|
| Error | 0.6 |
| Cost | 904 |
| Alternative 3 | |
|---|---|
| Error | 0.7 |
| Cost | 648 |
| Alternative 4 | |
|---|---|
| Error | 13.2 |
| Cost | 320 |
| Alternative 5 | |
|---|---|
| Error | 24.8 |
| Cost | 834 |
| Alternative 6 | |
|---|---|
| Error | 31.1 |
| Cost | 64 |
| Alternative 7 | |
|---|---|
| Error | 61.9 |
| Cost | 64 |
| Alternative 8 | |
|---|---|
| Error | 61.9 |
| Cost | 64 |

if z < -9.9907464562040168e35 or 48.1760290749680209 < z Initial program 42.5
Taylor expanded around inf 0.4
Simplified0.4
Simplified0.4
if -9.9907464562040168e35 < z < 48.1760290749680209Initial program 0.3
Simplified0.3
Final simplification0.3
herbie shell --seed 2021044
(FPCore (x y z)
:name "Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, B"
:precision binary64
:herbie-target
(if (< z -8120153.652456675) (- (* (+ (/ 0.07512208616047561 z) 0.0692910599291889) y) (- (/ (* 0.40462203869992125 y) (* z z)) x)) (if (< z 6.576118972787377e+20) (+ x (* (* y (+ (* (+ (* z 0.0692910599291889) 0.4917317610505968) z) 0.279195317918525)) (/ 1.0 (+ (* (+ z 6.012459259764103) z) 3.350343815022304)))) (- (* (+ (/ 0.07512208616047561 z) 0.0692910599291889) y) (- (/ (* 0.40462203869992125 y) (* z z)) x))))
(+ x (/ (* y (+ (* (+ (* z 0.0692910599291889) 0.4917317610505968) z) 0.279195317918525)) (+ (* (+ z 6.012459259764103) z) 3.350343815022304))))