(- (/ x (tanh x)) 1)

Average Error: 14.7 → 14.7

Time: 941.0ms

Precision: binary64

• could not determine a ground truth for program body

  1. x = 1.148547277859303e+16

Math

\[\frac{x}{\tanh x} - 1\]

↓

\[\frac{x}{\tanh x} - 1\]

C

double code(double x) {
	return ((double) (((double) (x / ((double) tanh(x)))) - 1.0));
}

↓

double code(double x) {
	return ((double) (((double) (x / ((double) tanh(x)))) - 1.0));
}

Error

Bits error versus x

Derivation

1. Initial program 14.7

   \[\frac{x}{\tanh x} - 1\]

2. Final simplification 14.7

   \[\leadsto \frac{x}{\tanh x} - 1\]

Reproduce

herbie shell --seed 2020153 
(FPCore (x)
  :name "(- (/ x (tanh x)) 1)"
  :precision binary64
  (- (/ x (tanh x)) 1.0))