neg log

Average Error: 0.0 → 0.0

Time: 5.5s

Precision: 64

Math

\[-\log \left(\frac{1}{x} - 1\right)\]

↓

\[-\log \left(\frac{1}{x} - 1\right)\]

C

double f(double x) {
        double r171674 = 1.0;
        double r171675 = x;
        double r171676 = r171674 / r171675;
        double r171677 = r171676 - r171674;
        double r171678 = log(r171677);
        double r171679 = -r171678;
        return r171679;
}

↓

double f(double x) {
        double r171680 = 1.0;
        double r171681 = x;
        double r171682 = r171680 / r171681;
        double r171683 = r171682 - r171680;
        double r171684 = log(r171683);
        double r171685 = -r171684;
        return r171685;
}

Error

Bits error versus x

Derivation

1. Initial program 0.0

   \[-\log \left(\frac{1}{x} - 1\right)\]

2. Final simplification 0.0

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

Reproduce

herbie shell --seed 2019179 
(FPCore (x)
  :name "neg log"
  (- (log (- (/ 1.0 x) 1.0))))