Average Error: 24.9 → 6.0
Time: 10.6s
Precision: binary64
\[[x, y]=\mathsf{sort}([x, y])\]
\[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
\[\begin{array}{l} \mathbf{if}\;z \leq -8.914868256338495 \cdot 10^{+147}:\\ \;\;\;\;-x \cdot y\\ \mathbf{elif}\;z \leq 3.444061843611629 \cdot 10^{+76}:\\ \;\;\;\;x \cdot \left(y \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array}\]
\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}
\begin{array}{l}
\mathbf{if}\;z \leq -8.914868256338495 \cdot 10^{+147}:\\
\;\;\;\;-x \cdot y\\

\mathbf{elif}\;z \leq 3.444061843611629 \cdot 10^{+76}:\\
\;\;\;\;x \cdot \left(y \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\

\mathbf{else}:\\
\;\;\;\;x \cdot y\\

\end{array}
(FPCore (x y z t a)
 :precision binary64
 (/ (* (* x y) z) (sqrt (- (* z z) (* t a)))))
(FPCore (x y z t a)
 :precision binary64
 (if (<= z -8.914868256338495e+147)
   (- (* x y))
   (if (<= z 3.444061843611629e+76)
     (* x (* y (/ z (sqrt (- (* z z) (* t a))))))
     (* x y))))
double code(double x, double y, double z, double t, double a) {
	return ((x * y) * z) / sqrt((z * z) - (t * a));
}
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (z <= -8.914868256338495e+147) {
		tmp = -(x * y);
	} else if (z <= 3.444061843611629e+76) {
		tmp = x * (y * (z / sqrt((z * z) - (t * a))));
	} else {
		tmp = x * y;
	}
	return tmp;
}

Error

Bits error versus x

Bits error versus y

Bits error versus z

Bits error versus t

Bits error versus a

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original24.9
Target7.5
Herbie6.0
\[\begin{array}{l} \mathbf{if}\;z < -3.1921305903852764 \cdot 10^{+46}:\\ \;\;\;\;-y \cdot x\\ \mathbf{elif}\;z < 5.976268120920894 \cdot 10^{+90}:\\ \;\;\;\;\frac{x \cdot z}{\frac{\sqrt{z \cdot z - a \cdot t}}{y}}\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array}\]

Derivation

  1. Split input into 3 regimes
  2. if z < -8.9148682563384953e147

    1. Initial program 52.9

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Taylor expanded around -inf 1.1

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

    if -8.9148682563384953e147 < z < 3.4440618436116288e76

    1. Initial program 10.8

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Using strategy rm
    3. Applied *-un-lft-identity_binary6410.8

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\sqrt{\color{blue}{1 \cdot \left(z \cdot z - t \cdot a\right)}}}\]
    4. Applied sqrt-prod_binary6410.8

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\color{blue}{\sqrt{1} \cdot \sqrt{z \cdot z - t \cdot a}}}\]
    5. Applied times-frac_binary649.0

      \[\leadsto \color{blue}{\frac{x \cdot y}{\sqrt{1}} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}}\]
    6. Simplified9.0

      \[\leadsto \color{blue}{\left(x \cdot y\right)} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\]
    7. Using strategy rm
    8. Applied associate-*l*_binary648.7

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

    if 3.4440618436116288e76 < z

    1. Initial program 40.3

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Taylor expanded around inf 2.7

      \[\leadsto \color{blue}{x \cdot y}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification6.0

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -8.914868256338495 \cdot 10^{+147}:\\ \;\;\;\;-x \cdot y\\ \mathbf{elif}\;z \leq 3.444061843611629 \cdot 10^{+76}:\\ \;\;\;\;x \cdot \left(y \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array}\]

Alternatives

Reproduce

herbie shell --seed 2021118 
(FPCore (x y z t a)
  :name "Statistics.Math.RootFinding:ridders from math-functions-0.1.5.2"
  :precision binary64

  :herbie-target
  (if (< z -3.1921305903852764e+46) (- (* y x)) (if (< z 5.976268120920894e+90) (/ (* x z) (/ (sqrt (- (* z z) (* a t))) y)) (* y x)))

  (/ (* (* x y) z) (sqrt (- (* z z) (* t a)))))