\frac{\varepsilon \cdot \left(e^{\left(a + b\right) \cdot \varepsilon} - 1\right)}{\left(e^{a \cdot \varepsilon} - 1\right) \cdot \left(e^{b \cdot \varepsilon} - 1\right)}\begin{array}{l}
\mathbf{if}\;a \le -173005857.2304000556468963623046875 \lor \neg \left(a \le 100503816208437458162455618952188928196600\right):\\
\;\;\;\;\frac{\varepsilon \cdot \sqrt[3]{{\left({\left(e^{a + b}\right)}^{\varepsilon} - 1\right)}^{3}}}{\left({\left(e^{a}\right)}^{\varepsilon} - 1\right) \cdot \mathsf{fma}\left(b, \varepsilon, {b}^{2} \cdot \left(\frac{1}{2} \cdot {\varepsilon}^{2} + \left(\frac{1}{6} \cdot {\varepsilon}^{3}\right) \cdot b\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{\varepsilon \cdot \left(e^{\left(a + b\right) \cdot \varepsilon} - 1\right)}{\mathsf{fma}\left(a, \varepsilon, {\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot {a}^{2} + \left(\frac{1}{6} \cdot {a}^{3}\right) \cdot \varepsilon\right)\right) \cdot \left(e^{b \cdot \varepsilon} - 1\right)}\\
\end{array}double f(double a, double b, double eps) {
double r145326 = eps;
double r145327 = a;
double r145328 = b;
double r145329 = r145327 + r145328;
double r145330 = r145329 * r145326;
double r145331 = exp(r145330);
double r145332 = 1.0;
double r145333 = r145331 - r145332;
double r145334 = r145326 * r145333;
double r145335 = r145327 * r145326;
double r145336 = exp(r145335);
double r145337 = r145336 - r145332;
double r145338 = r145328 * r145326;
double r145339 = exp(r145338);
double r145340 = r145339 - r145332;
double r145341 = r145337 * r145340;
double r145342 = r145334 / r145341;
return r145342;
}
double f(double a, double b, double eps) {
double r145343 = a;
double r145344 = -173005857.23040006;
bool r145345 = r145343 <= r145344;
double r145346 = 1.0050381620843746e+41;
bool r145347 = r145343 <= r145346;
double r145348 = !r145347;
bool r145349 = r145345 || r145348;
double r145350 = eps;
double r145351 = b;
double r145352 = r145343 + r145351;
double r145353 = exp(r145352);
double r145354 = pow(r145353, r145350);
double r145355 = 1.0;
double r145356 = r145354 - r145355;
double r145357 = 3.0;
double r145358 = pow(r145356, r145357);
double r145359 = cbrt(r145358);
double r145360 = r145350 * r145359;
double r145361 = exp(r145343);
double r145362 = pow(r145361, r145350);
double r145363 = r145362 - r145355;
double r145364 = 2.0;
double r145365 = pow(r145351, r145364);
double r145366 = 0.5;
double r145367 = pow(r145350, r145364);
double r145368 = r145366 * r145367;
double r145369 = 0.16666666666666666;
double r145370 = pow(r145350, r145357);
double r145371 = r145369 * r145370;
double r145372 = r145371 * r145351;
double r145373 = r145368 + r145372;
double r145374 = r145365 * r145373;
double r145375 = fma(r145351, r145350, r145374);
double r145376 = r145363 * r145375;
double r145377 = r145360 / r145376;
double r145378 = r145352 * r145350;
double r145379 = exp(r145378);
double r145380 = r145379 - r145355;
double r145381 = r145350 * r145380;
double r145382 = pow(r145343, r145364);
double r145383 = r145366 * r145382;
double r145384 = pow(r145343, r145357);
double r145385 = r145369 * r145384;
double r145386 = r145385 * r145350;
double r145387 = r145383 + r145386;
double r145388 = r145367 * r145387;
double r145389 = fma(r145343, r145350, r145388);
double r145390 = r145351 * r145350;
double r145391 = exp(r145390);
double r145392 = r145391 - r145355;
double r145393 = r145389 * r145392;
double r145394 = r145381 / r145393;
double r145395 = r145349 ? r145377 : r145394;
return r145395;
}




Bits error versus a




Bits error versus b




Bits error versus eps
| Original | 60.3 |
|---|---|
| Target | 15.0 |
| Herbie | 50.6 |
if a < -173005857.23040006 or 1.0050381620843746e+41 < a Initial program 55.1
Taylor expanded around 0 50.1
Simplified47.7
Taylor expanded around inf 47.7
Simplified49.1
rmApplied add-cbrt-cube49.1
Simplified42.1
if -173005857.23040006 < a < 1.0050381620843746e+41Initial program 63.9
Taylor expanded around 0 56.4
Simplified56.4
Final simplification50.6
herbie shell --seed 2019303 +o rules:numerics
(FPCore (a b eps)
:name "expq3 (problem 3.4.2)"
:precision binary64
:pre (and (< -1 eps) (< eps 1))
:herbie-target
(/ (+ a b) (* a b))
(/ (* eps (- (exp (* (+ a b) eps)) 1)) (* (- (exp (* a eps)) 1) (- (exp (* b eps)) 1))))