Average Error: 29.0 → 0.0
Time: 8.0s
Precision: binary64
\[\]
↓
\[\]
↓
double code(double x, double y) {
	return ((double) (((double) (2.0 / ((double) (1.0 + ((double) exp(((double) (-2.0 * x)))))))) - 1.0));
}

↓
double code(double x, double y) {
	double VAR;
	if ((x <= -0.0007310721182552102)) {
		VAR = ((double) (((double) (((double) (((double) (2.0 * ((double) sqrt(2.0)))) * ((double) pow(((double) (((double) sqrt(2.0)) / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))), 3.0)))) - ((double) pow(1.0, 3.0)))) / ((double) (((double) (1.0 * 1.0)) + ((double) (2.0 * ((double) (((double) (1.0 + ((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))))) / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x))))))))))));
	} else {
		double VAR_1;
		if ((x <= 0.0007244127199939371)) {
			VAR_1 = ((double) (((double) (x * 1.0)) - ((double) (((double) pow(x, 3.0)) * ((double) (((double) (x * 5.551115123125783e-17)) + 0.33333333333333337))))));
		} else {
			VAR_1 = ((double) (((double) (((double) (((double) (((double) pow(((double) pow(((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))), 3.0)), 6.0)) - ((double) pow(((double) pow(1.0, 3.0)), 6.0)))) / ((double) (((double) pow(((double) pow(((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))), 3.0)), 3.0)) + ((double) pow(((double) pow(1.0, 3.0)), 3.0)))))) / ((double) (((double) pow(((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))), 6.0)) + ((double) (((double) pow(1.0, 6.0)) + ((double) (((double) pow(1.0, 3.0)) * ((double) pow(((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))), 3.0)))))))))) / ((double) (((double) (1.0 * 1.0)) + ((double) (2.0 * ((double) (((double) (1.0 + ((double) (2.0 / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x)))))))) / ((double) (1.0 + ((double) pow(((double) exp(-2.0)), x))))))))))));
		}
		VAR = VAR_1;
	}
	return VAR;
}

Error
Bits error versus x
Bits error versus y
Try it out
Your Program's Arguments
Results
Enter valid numbers for all inputs
Derivation
  1. Split input into 3 regimes
  2. if  x  < -7.3107211825521024e-4
    1. Initial program 0.0
      \[\]
    2. Using strategy rm
    3. Applied flip3--0.0
      \[\leadsto \]
    4. Simplified0.0
      \[\leadsto \]
    5. Simplified0.0
      \[\leadsto \]
    6. Using strategy rm
    7. Applied *-un-lft-identity0.0
      \[\leadsto \]
    8. Applied add-sqr-sqrt0.0
      \[\leadsto \]
    9. Applied times-frac0.0
      \[\leadsto \]
    10. Applied unpow-prod-down0.0
      \[\leadsto \]
    11. Simplified0.0
      \[\leadsto \]
    if -7.3107211825521024e-4 <  x  < 7.244127199939371e-4
    1. Initial program 59.4
      \[\]
    2. Taylor expanded around 0 0.0
      \[\leadsto \]
    3. Simplified0.0
      \[\leadsto \]
    if 7.244127199939371e-4 <  x 
    1. Initial program 0.1
      \[\]
    2. Using strategy rm
    3. Applied flip3--0.1
      \[\leadsto \]
    4. Simplified0.1
      \[\leadsto \]
    5. Simplified0.1
      \[\leadsto \]
    6. Using strategy rm
    7. Applied flip3--0.1
      \[\leadsto \]
    8. Simplified0.1
      \[\leadsto \]
    9. Using strategy rm
    10. Applied flip--0.1
      \[\leadsto \]
    11. Simplified0.1
      \[\leadsto \]
  3. Recombined 3 regimes into one program.
  4. Final simplification0.0
    \[\leadsto \]
Reproduce
herbie shell --seed 2020190 
(FPCore (x y)
  :name "Logistic function from Lakshay Garg"
  :precision binary64
  (- (/ 2.0 (+ 1.0 (exp (* -2.0 x)))) 1.0))