Average Error: 0.3 → 0.3
Time: 1.8s
Precision: binary64
\[\log \left(1 - \frac{1}{1 + e^{-x}}\right)\]
\[\log \left(1 - \frac{1}{1 + e^{-x}}\right)\]

Error

Bits error versus x

Derivation

  1. Initial program 0.3

    \[\log \left(1 - \frac{1}{1 + e^{-x}}\right)\]
  2. Final simplification0.3

    \[\leadsto \log \left(1 - \frac{1}{1 + e^{-x}}\right)\]

Reproduce

herbie shell --seed 2020153 
(FPCore (x)
  :name "(log (- 1 (/ 1 (+ 1 (exp (- x))))))"
  :precision binary64
  (log (- 1.0 (/ 1.0 (+ 1.0 (exp (neg x)))))))