1 - \sqrt{0.5 \cdot \left(1 + \frac{1}{\mathsf{hypot}\left(1, x\right)}\right)}\frac{\frac{0.125 - \log \left(e^{{\left(\frac{0.5}{\mathsf{hypot}\left(1, x\right)}\right)}^{3}}\right)}{0.25 + \frac{0.25 + \frac{0.25}{\mathsf{hypot}\left(1, x\right)}}{\mathsf{hypot}\left(1, x\right)}}}{1 + \sqrt{0.5 + \frac{0.5}{\mathsf{hypot}\left(1, x\right)}}}(FPCore (x) :precision binary64 (- 1.0 (sqrt (* 0.5 (+ 1.0 (/ 1.0 (hypot 1.0 x)))))))
(FPCore (x) :precision binary64 (/ (/ (- 0.125 (log (exp (pow (/ 0.5 (hypot 1.0 x)) 3.0)))) (+ 0.25 (/ (+ 0.25 (/ 0.25 (hypot 1.0 x))) (hypot 1.0 x)))) (+ 1.0 (sqrt (+ 0.5 (/ 0.5 (hypot 1.0 x)))))))
double code(double x) {
return 1.0 - sqrt(0.5 * (1.0 + (1.0 / hypot(1.0, x))));
}
double code(double x) {
return ((0.125 - log(exp(pow((0.5 / hypot(1.0, x)), 3.0)))) / (0.25 + ((0.25 + (0.25 / hypot(1.0, x))) / hypot(1.0, x)))) / (1.0 + sqrt(0.5 + (0.5 / hypot(1.0, x))));
}



Bits error versus x
Results
Initial program 15.2
Simplified15.2
rmApplied flip--_binary6415.2
Simplified14.7
rmApplied flip3--_binary6414.7
Simplified14.7
Simplified14.7
rmApplied add-log-exp_binary6414.8
Final simplification14.8
herbie shell --seed 2020253
(FPCore (x)
:name "Given's Rotation SVD example, simplified"
:precision binary64
(- 1.0 (sqrt (* 0.5 (+ 1.0 (/ 1.0 (hypot 1.0 x)))))))