\frac{2}{e^{x} + e^{-x}}\log \left(e^{\frac{2}{e^{x} + e^{-x}}}\right)double f(double x) {
double r1922543 = 2.0;
double r1922544 = x;
double r1922545 = exp(r1922544);
double r1922546 = -r1922544;
double r1922547 = exp(r1922546);
double r1922548 = r1922545 + r1922547;
double r1922549 = r1922543 / r1922548;
return r1922549;
}
double f(double x) {
double r1922550 = 2.0;
double r1922551 = x;
double r1922552 = exp(r1922551);
double r1922553 = -r1922551;
double r1922554 = exp(r1922553);
double r1922555 = r1922552 + r1922554;
double r1922556 = r1922550 / r1922555;
double r1922557 = exp(r1922556);
double r1922558 = log(r1922557);
return r1922558;
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-log-exp0.2
Final simplification0.2
herbie shell --seed 2019192
(FPCore (x)
:name "Hyperbolic secant"
(/ 2.0 (+ (exp x) (exp (- x)))))