\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 1.1199581729972231 \cdot 10^{+123}:\\
\;\;\;\;\frac{1}{b} + \frac{1}{a}\\
\mathbf{elif}\;a \le 2.335242954070617 \cdot 10^{+248}:\\
\;\;\;\;\frac{1}{\frac{\frac{\mathsf{expm1}\left(a \cdot \varepsilon\right)}{\varepsilon}}{\frac{\mathsf{expm1}\left(\mathsf{fma}\left(\varepsilon, b, a \cdot \varepsilon\right)\right)}{\mathsf{expm1}\left(b \cdot \varepsilon\right)}}}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{b} + \frac{1}{a}\\
\end{array}double f(double a, double b, double eps) {
double r3631814 = eps;
double r3631815 = a;
double r3631816 = b;
double r3631817 = r3631815 + r3631816;
double r3631818 = r3631817 * r3631814;
double r3631819 = exp(r3631818);
double r3631820 = 1.0;
double r3631821 = r3631819 - r3631820;
double r3631822 = r3631814 * r3631821;
double r3631823 = r3631815 * r3631814;
double r3631824 = exp(r3631823);
double r3631825 = r3631824 - r3631820;
double r3631826 = r3631816 * r3631814;
double r3631827 = exp(r3631826);
double r3631828 = r3631827 - r3631820;
double r3631829 = r3631825 * r3631828;
double r3631830 = r3631822 / r3631829;
return r3631830;
}
double f(double a, double b, double eps) {
double r3631831 = a;
double r3631832 = 1.1199581729972231e+123;
bool r3631833 = r3631831 <= r3631832;
double r3631834 = 1.0;
double r3631835 = b;
double r3631836 = r3631834 / r3631835;
double r3631837 = r3631834 / r3631831;
double r3631838 = r3631836 + r3631837;
double r3631839 = 2.335242954070617e+248;
bool r3631840 = r3631831 <= r3631839;
double r3631841 = eps;
double r3631842 = r3631831 * r3631841;
double r3631843 = expm1(r3631842);
double r3631844 = r3631843 / r3631841;
double r3631845 = fma(r3631841, r3631835, r3631842);
double r3631846 = expm1(r3631845);
double r3631847 = r3631835 * r3631841;
double r3631848 = expm1(r3631847);
double r3631849 = r3631846 / r3631848;
double r3631850 = r3631844 / r3631849;
double r3631851 = r3631834 / r3631850;
double r3631852 = r3631840 ? r3631851 : r3631838;
double r3631853 = r3631833 ? r3631838 : r3631852;
return r3631853;
}




Bits error versus a




Bits error versus b




Bits error versus eps
| Original | 58.8 |
|---|---|
| Target | 14.2 |
| Herbie | 3.9 |
if a < 1.1199581729972231e+123 or 2.335242954070617e+248 < a Initial program 59.2
Simplified27.8
Taylor expanded around 0 2.7
if 1.1199581729972231e+123 < a < 2.335242954070617e+248Initial program 53.6
Simplified16.1
rmApplied clear-num16.1
Simplified16.8
Final simplification3.9
herbie shell --seed 2019152 +o rules:numerics
(FPCore (a b eps)
:name "expq3 (problem 3.4.2)"
: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))))