Average Error: 30.6 → 0.0
Time: 10.2s
Precision: 64
\[\frac{1 - \cos x}{\sin x}\]
\[\tan \left(\frac{x}{2}\right)\]
\frac{1 - \cos x}{\sin x}
\tan \left(\frac{x}{2}\right)
double f(double x) {
        double r2115938 = 1.0;
        double r2115939 = x;
        double r2115940 = cos(r2115939);
        double r2115941 = r2115938 - r2115940;
        double r2115942 = sin(r2115939);
        double r2115943 = r2115941 / r2115942;
        return r2115943;
}

double f(double x) {
        double r2115944 = x;
        double r2115945 = 2.0;
        double r2115946 = r2115944 / r2115945;
        double r2115947 = tan(r2115946);
        return r2115947;
}

Error

Bits error versus x

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original30.6
Target0.0
Herbie0.0
\[\tan \left(\frac{x}{2}\right)\]

Derivation

  1. Initial program 30.6

    \[\frac{1 - \cos x}{\sin x}\]
  2. Simplified0.0

    \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right)}\]
  3. Final simplification0.0

    \[\leadsto \tan \left(\frac{x}{2}\right)\]

Reproduce

herbie shell --seed 2019164 
(FPCore (x)
  :name "tanhf (example 3.4)"
  :herbie-expected 2

  :herbie-target
  (tan (/ x 2))

  (/ (- 1 (cos x)) (sin x)))