Average Error: 5.7 → 0.8
Time: 5.6s
Precision: binary64
\[\]
\[\]
double code(double x, double y, double z) {
	return ((double) (((double) (((double) (((double) (((double) (x - 0.5)) * ((double) log(x)))) - x)) + 0.91893853320467)) + ((double) (((double) (((double) (((double) (((double) (((double) (y + 0.0007936500793651)) * z)) - 0.0027777777777778)) * z)) + 0.083333333333333)) / x))));
}
double code(double x, double y, double z) {
	double VAR;
	if ((x <= 8.137335746669422e+97)) {
		VAR = ((double) (((double) (((double) (((double) (((double) (((double) log(x)) * ((double) (((double) (x * x)) - ((double) (0.5 * 0.5)))))) / ((double) (x + 0.5)))) - x)) + 0.91893853320467)) + ((double) (((double) (((double) (z * ((double) (((double) (((double) (y + 0.0007936500793651)) * z)) - 0.0027777777777778)))) + 0.083333333333333)) / x))));
	} else {
		VAR = ((double) (((double) (0.91893853320467 + ((double) (((double) (((double) (x - 0.5)) * ((double) log(((double) (((double) cbrt(x)) * ((double) cbrt(x)))))))) + ((double) (((double) (((double) (x - 0.5)) * ((double) log(((double) cbrt(x)))))) - x)))))) + ((double) (((double) (((double) (y + 0.0007936500793651)) * ((double) (z * ((double) (z / x)))))) - ((double) (0.0027777777777778 * ((double) (z / x))))))));
	}
	return VAR;
}

Error

Bits error versus x

Bits error versus y

Bits error versus z

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original5.7
Target1.1
Herbie0.8
\[\]

Derivation

  1. Split input into 2 regimes
  2. if x < 8.1373357466694218e97

    1. Initial program 1.1

      \[\]
    2. Using strategy rm
    3. Applied flip--1.1

      \[\leadsto \]
    4. Applied associate-*l/1.1

      \[\leadsto \]
    5. Simplified1.1

      \[\leadsto \]

    if 8.1373357466694218e97 < x

    1. Initial program 12.3

      \[\]
    2. Using strategy rm
    3. Applied add-cube-cbrt12.3

      \[\leadsto \]
    4. Applied log-prod12.4

      \[\leadsto \]
    5. Applied distribute-lft-in12.4

      \[\leadsto \]
    6. Applied associate--l+12.3

      \[\leadsto \]
    7. Taylor expanded around inf 12.4

      \[\leadsto \]
    8. Simplified0.5

      \[\leadsto \]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.8

    \[\leadsto \]

Reproduce

herbie shell --seed 2020192 
(FPCore (x y z)
  :name "Numeric.SpecFunctions:$slogFactorial from math-functions-0.1.5.2, B"
  :precision binary64

  :herbie-target
  (+ (+ (+ (* (- x 0.5) (log x)) (- 0.91893853320467 x)) (/ 0.083333333333333 x)) (* (/ z x) (- (* z (+ y 0.0007936500793651)) 0.0027777777777778)))

  (+ (+ (- (* (- x 0.5) (log x)) x) 0.91893853320467) (/ (+ (* (- (* (+ y 0.0007936500793651) z) 0.0027777777777778) z) 0.083333333333333) x)))