\frac{2}{e^{x} + e^{-x}}\sqrt{\frac{2}{e^{x} + e^{-x}}} \cdot \sqrt{\frac{1}{\cosh x}}(FPCore (x) :precision binary64 (/ 2.0 (+ (exp x) (exp (- x)))))
(FPCore (x) :precision binary64 (* (sqrt (/ 2.0 (+ (exp x) (exp (- x))))) (sqrt (/ 1.0 (cosh x)))))
double code(double x) {
return 2.0 / (exp(x) + exp(-x));
}
double code(double x) {
return sqrt(2.0 / (exp(x) + exp(-x))) * sqrt(1.0 / cosh(x));
}



Bits error versus x
Results
Initial program 0.0
rmApplied add-sqr-sqrt_binary64_7820.0
rmApplied clear-num_binary64_7590.0
Simplified0.0
Final simplification0.0
herbie shell --seed 2020355
(FPCore (x)
:name "Hyperbolic secant"
:precision binary64
(/ 2.0 (+ (exp x) (exp (- x)))))