\frac{x}{x \cdot x + 1}\begin{array}{l}
\mathbf{if}\;x \le -96697665796.7887421 \lor \neg \left(x \le 466.875941670613145\right):\\
\;\;\;\;\frac{1}{x} + \left(\frac{1}{{x}^{5}} - \frac{1}{{x}^{3}}\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{x}{\mathsf{fma}\left(-1, 1, {x}^{4}\right)} \cdot \left(x \cdot x - 1\right)\\
\end{array}double f(double x) {
double r77767 = x;
double r77768 = r77767 * r77767;
double r77769 = 1.0;
double r77770 = r77768 + r77769;
double r77771 = r77767 / r77770;
return r77771;
}
double f(double x) {
double r77772 = x;
double r77773 = -96697665796.78874;
bool r77774 = r77772 <= r77773;
double r77775 = 466.87594167061314;
bool r77776 = r77772 <= r77775;
double r77777 = !r77776;
bool r77778 = r77774 || r77777;
double r77779 = 1.0;
double r77780 = r77779 / r77772;
double r77781 = 1.0;
double r77782 = 5.0;
double r77783 = pow(r77772, r77782);
double r77784 = r77781 / r77783;
double r77785 = 3.0;
double r77786 = pow(r77772, r77785);
double r77787 = r77781 / r77786;
double r77788 = r77784 - r77787;
double r77789 = r77780 + r77788;
double r77790 = -r77781;
double r77791 = 4.0;
double r77792 = pow(r77772, r77791);
double r77793 = fma(r77790, r77781, r77792);
double r77794 = r77772 / r77793;
double r77795 = r77772 * r77772;
double r77796 = r77795 - r77781;
double r77797 = r77794 * r77796;
double r77798 = r77778 ? r77789 : r77797;
return r77798;
}




Bits error versus x
| Original | 15.1 |
|---|---|
| Target | 0.1 |
| Herbie | 0.0 |
if x < -96697665796.78874 or 466.87594167061314 < x Initial program 30.2
rmApplied flip-+48.6
Applied associate-/r/48.6
Simplified48.6
Taylor expanded around inf 0.0
Simplified0.0
if -96697665796.78874 < x < 466.87594167061314Initial program 0.0
rmApplied flip-+0.0
Applied associate-/r/0.0
Simplified0.0
Final simplification0.0
herbie shell --seed 2020060 +o rules:numerics
(FPCore (x)
:name "x / (x^2 + 1)"
:precision binary64
:herbie-target
(/ 1 (+ x (/ 1 x)))
(/ x (+ (* x x) 1)))