Average Error: 0.0 → 0.0
Time: 2.4s
Precision: 64
\[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673003\]
↓
\[\left(y \cdot x + \left(\left(-1\right) \cdot x - y \cdot 0.5\right)\right) + 0.918938533204673003\]
\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673003
↓
\left(y \cdot x + \left(\left(-1\right) \cdot x - y \cdot 0.5\right)\right) + 0.918938533204673003
double f(double x, double y) {
        double r62971 = x;
        double r62972 = y;
        double r62973 = 1.0;
        double r62974 = r62972 - r62973;
        double r62975 = r62971 * r62974;
        double r62976 = 0.5;
        double r62977 = r62972 * r62976;
        double r62978 = r62975 - r62977;
        double r62979 = 0.918938533204673;
        double r62980 = r62978 + r62979;
        return r62980;
}
↓
double f(double x, double y) {
        double r62981 = y;
        double r62982 = x;
        double r62983 = r62981 * r62982;
        double r62984 = 1.0;
        double r62985 = -r62984;
        double r62986 = r62985 * r62982;
        double r62987 = 0.5;
        double r62988 = r62981 * r62987;
        double r62989 = r62986 - r62988;
        double r62990 = r62983 + r62989;
        double r62991 = 0.918938533204673;
        double r62992 = r62990 + r62991;
        return r62992;
}

Error

Bits error versus x

Bits error versus y

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 0.0

    \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673003\]
  2. Using strategy rm

  3. Applied sub-neg0.0

    \[\leadsto \left(x \cdot \color{blue}{\left(y + \left(-1\right)\right)} - y \cdot 0.5\right) + 0.918938533204673003\]

  4. Applied distribute-rgt-in0.0

    \[\leadsto \left(\color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)} - y \cdot 0.5\right) + 0.918938533204673003\]

  5. Applied associate--l+0.0

    \[\leadsto \color{blue}{\left(y \cdot x + \left(\left(-1\right) \cdot x - y \cdot 0.5\right)\right)} + 0.918938533204673003\]

  6. Final simplification0.0

    \[\leadsto \left(y \cdot x + \left(\left(-1\right) \cdot x - y \cdot 0.5\right)\right) + 0.918938533204673003\]

Reproduce

herbie shell --seed 2020064 
(FPCore (x y)
  :name "Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, A"
  :precision binary64
  (+ (- (* x (- y 1)) (* y 0.5)) 0.918938533204673))