Average Error: 24.2 → 11.0
Time: 6.5s
Precision: binary64
\[\]
\[\]
\[\]
double code(double alpha, double beta, double i) {
	return ((double) (((double) (((double) (((double) (((double) (((double) (alpha + beta)) * ((double) (beta - alpha)))) / ((double) (((double) (alpha + beta)) + ((double) (2.0 * i)))))) / ((double) (((double) (((double) (alpha + beta)) + ((double) (2.0 * i)))) + 2.0)))) + 1.0)) / 2.0));
}
double code(double alpha, double beta, double i) {
	double VAR;
	if ((alpha <= 2.632083162561644e+221)) {
		VAR = ((double) (((double) (((double) (((double) (((double) (alpha + beta)) * ((double) (((double) cbrt(((double) (((double) (beta - alpha)) / ((double) (alpha + ((double) (beta + ((double) (2.0 * i)))))))))) * ((double) cbrt(((double) (((double) (beta - alpha)) / ((double) (alpha + ((double) (beta + ((double) (2.0 * i)))))))))))))) * ((double) (((double) cbrt(((double) (((double) (beta - alpha)) / ((double) (beta + ((double) (alpha + ((double) (2.0 * i)))))))))) / ((double) (alpha + ((double) (beta + ((double) (2.0 + ((double) (2.0 * i)))))))))))) + 1.0)) / 2.0));
	} else {
		VAR = ((double) (((double) (((double) (2.0 / alpha)) + ((double) (((double) (8.0 / ((double) pow(alpha, 3.0)))) - ((double) (4.0 / ((double) (alpha * alpha)))))))) / 2.0));
	}
	return VAR;
}

Error

Bits error versus alpha

Bits error versus beta

Bits error versus i

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if alpha < 2.632083162561644e221

    1. Initial program 20.0

      \[\]
    2. Simplified15.7

      \[\leadsto \]
    3. Using strategy rm
    4. Applied associate-/r*7.9

      \[\leadsto \]
    5. Simplified7.9

      \[\leadsto \]
    6. Using strategy rm
    7. Applied *-un-lft-identity7.9

      \[\leadsto \]
    8. Applied add-cube-cbrt7.9

      \[\leadsto \]
    9. Applied times-frac7.9

      \[\leadsto \]
    10. Applied associate-*r*7.9

      \[\leadsto \]
    11. Simplified7.9

      \[\leadsto \]

    if 2.632083162561644e221 < alpha

    1. Initial program 64.0

      \[\]
    2. Simplified56.4

      \[\leadsto \]
    3. Taylor expanded around inf 41.0

      \[\leadsto \]
    4. Simplified41.0

      \[\leadsto \]
  3. Recombined 2 regimes into one program.
  4. Final simplification11.0

    \[\leadsto \]

Reproduce

herbie shell --seed 2020192 
(FPCore (alpha beta i)
  :name "Octave 3.8, jcobi/2"
  :precision binary64
  :pre (and (> alpha -1.0) (> beta -1.0) (> i 0.0))
  (/ (+ (/ (/ (* (+ alpha beta) (- beta alpha)) (+ (+ alpha beta) (* 2.0 i))) (+ (+ (+ alpha beta) (* 2.0 i)) 2.0)) 1.0) 2.0))