\frac{1 + \tanh \left(\frac{x}{2}\right)}{1 - \tanh \left(\frac{x}{2}\right)}\frac{1 + \tanh \left(\frac{x}{2}\right)}{1 - \tanh \left(\frac{x}{2}\right)}double code(double x) {
return ((double) (((double) (1.0 + ((double) tanh(((double) (x / 2.0)))))) / ((double) (1.0 - ((double) tanh(((double) (x / 2.0))))))));
}
double code(double x) {
return ((double) (((double) (1.0 + ((double) tanh(((double) (x / 2.0)))))) / ((double) (1.0 - ((double) tanh(((double) (x / 2.0))))))));
}



Bits error versus x
Results
Initial program 0.2
Final simplification0.2
herbie shell --seed 2020153
(FPCore (x)
:name "(/ (+ 1 (tanh (/ x 2))) (- 1 (tanh (/ x 2))))"
:precision binary64
(/ (+ 1.0 (tanh (/ x 2.0))) (- 1.0 (tanh (/ x 2.0)))))