Average Error: 1.9 → 2.5
Time: 3.6s
Precision: binary64
\[\frac{x}{y} \cdot \left(z - t\right) + t\]
↓
\[\begin{array}{l} \mathbf{if}\;x \le -4.0517538917623928 \cdot 10^{144}:\\ \;\;\;\;x \cdot \left(\left(z - t\right) \cdot \frac{1}{y}\right) + t\\ \mathbf{elif}\;x \le 9.00134916517873369 \cdot 10^{-279}:\\ \;\;\;\;\frac{x \cdot \left(z - t\right)}{y} + t\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{y} \cdot \left(z - t\right) + t\\ \end{array}\]
\frac{x}{y} \cdot \left(z - t\right) + t
↓
\begin{array}{l}
\mathbf{if}\;x \le -4.0517538917623928 \cdot 10^{144}:\\
\;\;\;\;x \cdot \left(\left(z - t\right) \cdot \frac{1}{y}\right) + t\\

\mathbf{elif}\;x \le 9.00134916517873369 \cdot 10^{-279}:\\
\;\;\;\;\frac{x \cdot \left(z - t\right)}{y} + t\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{y} \cdot \left(z - t\right) + t\\

\end{array}
double code(double x, double y, double z, double t) {
	return ((double) (((double) (((double) (x / y)) * ((double) (z - t)))) + t));
}
↓
double code(double x, double y, double z, double t) {
	double VAR;
	if ((x <= -4.051753891762393e+144)) {
		VAR = ((double) (((double) (x * ((double) (((double) (z - t)) * ((double) (1.0 / y)))))) + t));
	} else {
		double VAR_1;
		if ((x <= 9.001349165178734e-279)) {
			VAR_1 = ((double) (((double) (((double) (x * ((double) (z - t)))) / y)) + t));
		} else {
			VAR_1 = ((double) (((double) (((double) (x / y)) * ((double) (z - t)))) + t));
		}
		VAR = VAR_1;
	}
	return VAR;
}

Error

Bits error versus x

Bits error versus y

Bits error versus z

Bits error versus t

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original1.9
Target2.3
Herbie2.5
\[\begin{array}{l} \mathbf{if}\;z \lt 2.7594565545626922 \cdot 10^{-282}:\\ \;\;\;\;\frac{x}{y} \cdot \left(z - t\right) + t\\ \mathbf{elif}\;z \lt 2.326994450874436 \cdot 10^{-110}:\\ \;\;\;\;x \cdot \frac{z - t}{y} + t\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{y} \cdot \left(z - t\right) + t\\ \end{array}\]

Derivation

  1. Split input into 3 regimes

  2. if x < -4.0517538917623928e144

    1. Initial program 5.7

      \[\frac{x}{y} \cdot \left(z - t\right) + t\]
    2. Using strategy rm

    3. Applied div-inv5.8

      \[\leadsto \color{blue}{\left(x \cdot \frac{1}{y}\right)} \cdot \left(z - t\right) + t\]

    4. Applied associate-*l*3.0

      \[\leadsto \color{blue}{x \cdot \left(\frac{1}{y} \cdot \left(z - t\right)\right)} + t\]

    5. Simplified2.9

      \[\leadsto x \cdot \color{blue}{\frac{z - t}{y}} + t\]
    6. Using strategy rm

    7. Applied div-inv3.0

      \[\leadsto x \cdot \color{blue}{\left(\left(z - t\right) \cdot \frac{1}{y}\right)} + t\]

    if -4.0517538917623928e144 < x < 9.00134916517873369e-279

    1. Initial program 1.2

      \[\frac{x}{y} \cdot \left(z - t\right) + t\]
    2. Using strategy rm

    3. Applied associate-*l/3.0

      \[\leadsto \color{blue}{\frac{x \cdot \left(z - t\right)}{y}} + t\]

    if 9.00134916517873369e-279 < x

    1. Initial program 2.0

      \[\frac{x}{y} \cdot \left(z - t\right) + t\]
  3. Recombined 3 regimes into one program.

  4. Final simplification2.5

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -4.0517538917623928 \cdot 10^{144}:\\ \;\;\;\;x \cdot \left(\left(z - t\right) \cdot \frac{1}{y}\right) + t\\ \mathbf{elif}\;x \le 9.00134916517873369 \cdot 10^{-279}:\\ \;\;\;\;\frac{x \cdot \left(z - t\right)}{y} + t\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{y} \cdot \left(z - t\right) + t\\ \end{array}\]

Reproduce

herbie shell --seed 2020155 
(FPCore (x y z t)
  :name "Numeric.Signal.Multichannel:$cget from hsignal-0.2.7.1"
  :precision binary64

  :herbie-target
  (if (< z 2.759456554562692e-282) (+ (* (/ x y) (- z t)) t) (if (< z 2.326994450874436e-110) (+ (* x (/ (- z t) y)) t) (+ (* (/ x y) (- z t)) t)))

  (+ (* (/ x y) (- z t)) t))