Average Error: 36.8 → 0.4
Time: 5.1s
Precision: binary64
\[\]
\[\]
double code(double x, double eps) {
	return ((double) (((double) sin(((double) (x + eps)))) - ((double) sin(x))));
}
double code(double x, double eps) {
	double VAR;
	if ((eps <= -9.845370976900334e-09)) {
		VAR = ((double) (((double) (((double) (((double) sin(x)) * ((double) cos(eps)))) + ((double) (((double) cos(x)) * ((double) sin(eps)))))) - ((double) sin(x))));
	} else {
		double VAR_1;
		if ((eps <= 6.897912047083434e-09)) {
			VAR_1 = ((double) (((double) (2.0 * ((double) sin(((double) (eps / 2.0)))))) * ((double) cos(((double) (((double) (x + ((double) (eps + x)))) / 2.0))))));
		} else {
			VAR_1 = ((double) (((double) (((double) sin(x)) * ((double) cos(eps)))) + ((double) (((double) (((double) cos(x)) * ((double) sin(eps)))) - ((double) sin(x))))));
		}
		VAR = VAR_1;
	}
	return VAR;
}

Error

Bits error versus x

Bits error versus eps

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original36.8
Target14.6
Herbie0.4
\[\]

Derivation

  1. Split input into 3 regimes
  2. if eps < -9.8453709769003335e-9

    1. Initial program 28.1

      \[\]
    2. Using strategy rm
    3. Applied sin-sum0.5

      \[\leadsto \]

    if -9.8453709769003335e-9 < eps < 6.897912047083434e-9

    1. Initial program 45.4

      \[\]
    2. Using strategy rm
    3. Applied diff-sin45.4

      \[\leadsto \]
    4. Simplified0.3

      \[\leadsto \]
    5. Using strategy rm
    6. Applied associate-*r*0.3

      \[\leadsto \]

    if 6.897912047083434e-9 < eps

    1. Initial program 29.4

      \[\]
    2. Using strategy rm
    3. Applied sin-sum0.5

      \[\leadsto \]
    4. Applied associate--l+0.5

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

    \[\leadsto \]

Reproduce

herbie shell --seed 2020179 
(FPCore (x eps)
  :name "2sin (example 3.3)"
  :precision binary64

  :herbie-target
  (* 2.0 (* (cos (+ x (/ eps 2.0))) (sin (/ eps 2.0))))

  (- (sin (+ x eps)) (sin x)))