\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(y + x\right) \cdot \left(x - y\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 r3881520 = x;
double r3881521 = y;
double r3881522 = r3881520 - r3881521;
double r3881523 = r3881520 + r3881521;
double r3881524 = r3881522 * r3881523;
double r3881525 = r3881520 * r3881520;
double r3881526 = r3881521 * r3881521;
double r3881527 = r3881525 + r3881526;
double r3881528 = r3881524 / r3881527;
return r3881528;
}
double f(double x, double y) {
double r3881529 = y;
double r3881530 = -1.3691694056010857e+154;
bool r3881531 = r3881529 <= r3881530;
double r3881532 = -1.0;
double r3881533 = -1.2013518175407308e-161;
bool r3881534 = r3881529 <= r3881533;
double r3881535 = x;
double r3881536 = r3881529 + r3881535;
double r3881537 = r3881535 - r3881529;
double r3881538 = r3881536 * r3881537;
double r3881539 = r3881529 * r3881529;
double r3881540 = r3881535 * r3881535;
double r3881541 = r3881539 + r3881540;
double r3881542 = r3881538 / r3881541;
double r3881543 = exp(r3881542);
double r3881544 = log(r3881543);
double r3881545 = 2.9860065638011237e-218;
bool r3881546 = r3881529 <= r3881545;
double r3881547 = 1.0;
double r3881548 = 1.2966442305400266e-202;
bool r3881549 = r3881529 <= r3881548;
double r3881550 = sqrt(r3881541);
double r3881551 = r3881536 / r3881550;
double r3881552 = r3881537 / r3881550;
double r3881553 = r3881551 * r3881552;
double r3881554 = r3881549 ? r3881532 : r3881553;
double r3881555 = r3881546 ? r3881547 : r3881554;
double r3881556 = r3881534 ? r3881544 : r3881555;
double r3881557 = r3881531 ? r3881532 : r3881556;
return r3881557;
}




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))))