\frac{2}{e^{x} + e^{-x}}\frac{\sqrt{2}}{\frac{\frac{e^{x} + e^{-x}}{\sqrt{\sqrt{2}}}}{\sqrt{\sqrt{2}}}}double f(double x) {
double r58605 = 2.0;
double r58606 = x;
double r58607 = exp(r58606);
double r58608 = -r58606;
double r58609 = exp(r58608);
double r58610 = r58607 + r58609;
double r58611 = r58605 / r58610;
return r58611;
}
double f(double x) {
double r58612 = 2.0;
double r58613 = sqrt(r58612);
double r58614 = x;
double r58615 = exp(r58614);
double r58616 = -r58614;
double r58617 = exp(r58616);
double r58618 = r58615 + r58617;
double r58619 = sqrt(r58613);
double r58620 = r58618 / r58619;
double r58621 = r58620 / r58619;
double r58622 = r58613 / r58621;
return r58622;
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-sqr-sqrt0.5
Applied associate-/l*0.5
rmApplied add-sqr-sqrt0.5
Applied sqrt-prod0.0
Applied associate-/r*0.0
Final simplification0.0
herbie shell --seed 2019362
(FPCore (x)
:name "Hyperbolic secant"
:precision binary64
(/ 2 (+ (exp x) (exp (- x)))))