\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}\left({\left(\frac{1}{k}\right)}^{\frac{1}{4}} \cdot 1\right) \cdot \frac{{\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{\sqrt{k}}}double code(double k, double n) {
return ((double) (((double) (1.0 / ((double) sqrt(k)))) * ((double) pow(((double) (((double) (2.0 * ((double) M_PI))) * n)), ((double) (((double) (1.0 - k)) / 2.0))))));
}
double code(double k, double n) {
return ((double) (((double) (((double) pow(((double) (1.0 / k)), 0.25)) * 1.0)) * ((double) (((double) pow(((double) (((double) (2.0 * ((double) M_PI))) * n)), ((double) (((double) (1.0 - k)) / 2.0)))) / ((double) sqrt(((double) sqrt(k))))))));
}



Bits error versus k



Bits error versus n
Results
Initial program 0.5
rmApplied add-sqr-sqrt0.5
Applied sqrt-prod0.6
Applied associate-/r*0.6
Taylor expanded around 0 2.7
Simplified0.6
rmApplied div-inv0.6
Applied associate-*l*0.6
Simplified0.6
Final simplification0.6
herbie shell --seed 2020162
(FPCore (k n)
:name "Migdal et al, Equation (51)"
:precision binary64
(* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))