\frac{2}{e^{x} + e^{-x}}\frac{\frac{\sqrt{2}}{\frac{\sqrt{e^{x} + e^{-x}}}{\sqrt{2}}}}{\sqrt{e^{x} + e^{-x}}}double f(double x) {
double r2656823 = 2.0;
double r2656824 = x;
double r2656825 = exp(r2656824);
double r2656826 = -r2656824;
double r2656827 = exp(r2656826);
double r2656828 = r2656825 + r2656827;
double r2656829 = r2656823 / r2656828;
return r2656829;
}
double f(double x) {
double r2656830 = 2.0;
double r2656831 = sqrt(r2656830);
double r2656832 = x;
double r2656833 = exp(r2656832);
double r2656834 = -r2656832;
double r2656835 = exp(r2656834);
double r2656836 = r2656833 + r2656835;
double r2656837 = sqrt(r2656836);
double r2656838 = r2656837 / r2656831;
double r2656839 = r2656831 / r2656838;
double r2656840 = r2656839 / r2656837;
return r2656840;
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-sqr-sqrt0.8
Applied associate-/r*0.5
rmApplied add-sqr-sqrt0.5
Applied associate-/l*0.0
Final simplification0.0
herbie shell --seed 2019200
(FPCore (x)
:name "Hyperbolic secant"
(/ 2.0 (+ (exp x) (exp (- x)))))