Average Error: 58.1 → 58.1
Time: 3.4s
Precision: binary64
Cost: 26176
\[\frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}\]
↓
\[\frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}\]
\frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}
↓
\frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}
(FPCore (x)
 :precision binary64
 (/ (- (exp x) (exp (- x))) (+ (exp x) (exp (- x)))))
↓
(FPCore (x)
 :precision binary64
 (/ (- (exp x) (exp (- x))) (+ (exp x) (exp (- x)))))
double code(double x) {
	return (exp(x) - exp(-x)) / (exp(x) + exp(-x));
}
↓
double code(double x) {
	return (exp(x) - exp(-x)) / (exp(x) + exp(-x));
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 58.1

    \[\frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}\]

Reproduce

herbie shell --seed 2021027 
(FPCore (x)
  :name "Hyperbolic tangent"
  :precision binary64
  (/ (- (exp x) (exp (- x))) (+ (exp x) (exp (- x)))))