double code(double a, double b, double eps) {
return ((double) (((double) (eps * ((double) (((double) exp(((double) (((double) (a + b)) * eps)))) - 1.0)))) / ((double) (((double) (((double) exp(((double) (a * eps)))) - 1.0)) * ((double) (((double) exp(((double) (b * eps)))) - 1.0))))));
}
double code(double a, double b, double eps) {
return ((double) (((double) (1.0 / ((double) (a + ((double) (((double) log(1.0)) + ((double) (eps * ((double) (0.5 * ((double) pow(((double) log(1.0)), 2.0)))))))))))) * ((double) (((double) (((double) pow(((double) exp(((double) (a + b)))), eps)) - 1.0)) / ((double) (((double) pow(((double) exp(b)), eps)) - 1.0))))));
}




Bits error versus a




Bits error versus b




Bits error versus eps
Results
| Original | 60.2 |
|---|---|
| Target | 15.0 |
| Herbie | 49.6 |
Initial program 60.2
Simplified60.4
Taylor expanded around 0 54.5
Simplified54.5
rmApplied *-un-lft-identity54.5
Applied times-frac54.5
Applied associate-*r*54.5
Simplified49.6
Final simplification49.6
herbie shell --seed 2020181
(FPCore (a b eps)
:name "expq3 (problem 3.4.2)"
:precision binary64
:pre (and (< -1.0 eps) (< eps 1.0))
:herbie-target
(/ (+ a b) (* a b))
(/ (* eps (- (exp (* (+ a b) eps)) 1.0)) (* (- (exp (* a eps)) 1.0) (- (exp (* b eps)) 1.0))))