\frac{\left(x - y\right) \cdot \left(x + y\right)}{x \cdot x + y \cdot y}\begin{array}{l}
\mathbf{if}\;y \le -1.3691694056010857 \cdot 10^{+154}:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \le -1.2013518175407308 \cdot 10^{-161}:\\
\;\;\;\;\log \left(e^{\frac{\left(x - y\right) \cdot \left(y + x\right)}{y \cdot y + x \cdot x}}\right)\\
\mathbf{elif}\;y \le 2.9860065638011237 \cdot 10^{-218}:\\
\;\;\;\;1\\
\mathbf{elif}\;y \le 1.2966442305400266 \cdot 10^{-202}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;\frac{y + x}{\sqrt{y \cdot y + x \cdot x}} \cdot \frac{x - y}{\sqrt{y \cdot y + x \cdot x}}\\
\end{array}double f(double x, double y) {
double r4423054 = x;
double r4423055 = y;
double r4423056 = r4423054 - r4423055;
double r4423057 = r4423054 + r4423055;
double r4423058 = r4423056 * r4423057;
double r4423059 = r4423054 * r4423054;
double r4423060 = r4423055 * r4423055;
double r4423061 = r4423059 + r4423060;
double r4423062 = r4423058 / r4423061;
return r4423062;
}
double f(double x, double y) {
double r4423063 = y;
double r4423064 = -1.3691694056010857e+154;
bool r4423065 = r4423063 <= r4423064;
double r4423066 = -1.0;
double r4423067 = -1.2013518175407308e-161;
bool r4423068 = r4423063 <= r4423067;
double r4423069 = x;
double r4423070 = r4423069 - r4423063;
double r4423071 = r4423063 + r4423069;
double r4423072 = r4423070 * r4423071;
double r4423073 = r4423063 * r4423063;
double r4423074 = r4423069 * r4423069;
double r4423075 = r4423073 + r4423074;
double r4423076 = r4423072 / r4423075;
double r4423077 = exp(r4423076);
double r4423078 = log(r4423077);
double r4423079 = 2.9860065638011237e-218;
bool r4423080 = r4423063 <= r4423079;
double r4423081 = 1.0;
double r4423082 = 1.2966442305400266e-202;
bool r4423083 = r4423063 <= r4423082;
double r4423084 = sqrt(r4423075);
double r4423085 = r4423071 / r4423084;
double r4423086 = r4423070 / r4423084;
double r4423087 = r4423085 * r4423086;
double r4423088 = r4423083 ? r4423066 : r4423087;
double r4423089 = r4423080 ? r4423081 : r4423088;
double r4423090 = r4423068 ? r4423078 : r4423089;
double r4423091 = r4423065 ? r4423066 : r4423090;
return r4423091;
}




Bits error versus x




Bits error versus y
Results
| Original | 19.7 |
|---|---|
| Target | 0.0 |
| Herbie | 5.7 |
if y < -1.3691694056010857e+154 or 2.9860065638011237e-218 < y < 1.2966442305400266e-202Initial program 60.1
Taylor expanded around 0 4.4
if -1.3691694056010857e+154 < y < -1.2013518175407308e-161Initial program 0.0
rmApplied add-sqr-sqrt0.0
Applied times-frac0.3
rmApplied add-log-exp0.3
Simplified0.0
if -1.2013518175407308e-161 < y < 2.9860065638011237e-218Initial program 28.8
Taylor expanded around inf 13.0
if 1.2966442305400266e-202 < y Initial program 6.3
rmApplied add-sqr-sqrt6.3
Applied times-frac6.9
Final simplification5.7
herbie shell --seed 2019163
(FPCore (x y)
:name "Kahan p9 Example"
:pre (and (< 0 x 1) (< y 1))
:herbie-target
(if (< 0.5 (fabs (/ x y)) 2) (/ (* (- x y) (+ x y)) (+ (* x x) (* y y))) (- 1 (/ 2 (+ 1 (* (/ x y) (/ x y))))))
(/ (* (- x y) (+ x y)) (+ (* x x) (* y y))))