\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}\frac{\sqrt{\left(0.5 \cdot 0.5\right) \cdot \left(\left(\frac{x \cdot x}{\sqrt{p \cdot \left(p \cdot 4\right) + x \cdot x}} \cdot \frac{x}{p \cdot \left(p \cdot 4\right) + x \cdot x}\right) \cdot 0.5 + 0.5\right)}}{\sqrt{\left(\frac{x}{\sqrt{p \cdot \left(p \cdot 4\right) + x \cdot x}} \cdot 0.5\right) \cdot \left(\frac{x}{\sqrt{p \cdot \left(p \cdot 4\right) + x \cdot x}} \cdot 0.5\right) + \left(0.5 \cdot 0.5 - 0.5 \cdot \left(\frac{x}{\sqrt{p \cdot \left(p \cdot 4\right) + x \cdot x}} \cdot 0.5\right)\right)}}double f(double p, double x) {
double r80197220 = 0.5;
double r80197221 = 1.0;
double r80197222 = x;
double r80197223 = 4.0;
double r80197224 = p;
double r80197225 = r80197223 * r80197224;
double r80197226 = r80197225 * r80197224;
double r80197227 = r80197222 * r80197222;
double r80197228 = r80197226 + r80197227;
double r80197229 = sqrt(r80197228);
double r80197230 = r80197222 / r80197229;
double r80197231 = r80197221 + r80197230;
double r80197232 = r80197220 * r80197231;
double r80197233 = sqrt(r80197232);
return r80197233;
}
double f(double p, double x) {
double r80197234 = 0.5;
double r80197235 = r80197234 * r80197234;
double r80197236 = x;
double r80197237 = r80197236 * r80197236;
double r80197238 = p;
double r80197239 = 4.0;
double r80197240 = r80197238 * r80197239;
double r80197241 = r80197238 * r80197240;
double r80197242 = r80197241 + r80197237;
double r80197243 = sqrt(r80197242);
double r80197244 = r80197237 / r80197243;
double r80197245 = r80197236 / r80197242;
double r80197246 = r80197244 * r80197245;
double r80197247 = r80197246 * r80197234;
double r80197248 = r80197247 + r80197234;
double r80197249 = r80197235 * r80197248;
double r80197250 = sqrt(r80197249);
double r80197251 = r80197236 / r80197243;
double r80197252 = r80197251 * r80197234;
double r80197253 = r80197252 * r80197252;
double r80197254 = r80197234 * r80197252;
double r80197255 = r80197235 - r80197254;
double r80197256 = r80197253 + r80197255;
double r80197257 = sqrt(r80197256);
double r80197258 = r80197250 / r80197257;
return r80197258;
}




Bits error versus p




Bits error versus x
Results
| Original | 13.3 |
|---|---|
| Target | 13.3 |
| Herbie | 13.7 |
Initial program 13.3
Simplified13.3
rmApplied flip3-+13.3
Applied sqrt-div13.3
Simplified13.7
Final simplification13.7
herbie shell --seed 2019120
(FPCore (p x)
:name "Given's Rotation SVD example"
:pre (< 1e-150 (fabs x) 1e+150)
:herbie-target
(sqrt (+ 1/2 (/ (copysign 1/2 x) (hypot 1 (/ (* 2 p) x)))))
(sqrt (* 0.5 (+ 1 (/ x (sqrt (+ (* (* 4 p) p) (* x x))))))))