Average Error: 25.1 → 5.9
Time: 8.7s
Precision: 64
\[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
\[\begin{array}{l} \mathbf{if}\;z \le -9.34194979807773912 \cdot 10^{151}:\\ \;\;\;\;-x \cdot y\\ \mathbf{elif}\;z \le 2.2349389384476415 \cdot 10^{125}:\\ \;\;\;\;y \cdot \left(x \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array}\]
\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}
\begin{array}{l}
\mathbf{if}\;z \le -9.34194979807773912 \cdot 10^{151}:\\
\;\;\;\;-x \cdot y\\

\mathbf{elif}\;z \le 2.2349389384476415 \cdot 10^{125}:\\
\;\;\;\;y \cdot \left(x \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\

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

\end{array}
double f(double x, double y, double z, double t, double a) {
        double r393407 = x;
        double r393408 = y;
        double r393409 = r393407 * r393408;
        double r393410 = z;
        double r393411 = r393409 * r393410;
        double r393412 = r393410 * r393410;
        double r393413 = t;
        double r393414 = a;
        double r393415 = r393413 * r393414;
        double r393416 = r393412 - r393415;
        double r393417 = sqrt(r393416);
        double r393418 = r393411 / r393417;
        return r393418;
}

double f(double x, double y, double z, double t, double a) {
        double r393419 = z;
        double r393420 = -9.341949798077739e+151;
        bool r393421 = r393419 <= r393420;
        double r393422 = x;
        double r393423 = y;
        double r393424 = r393422 * r393423;
        double r393425 = -r393424;
        double r393426 = 2.2349389384476415e+125;
        bool r393427 = r393419 <= r393426;
        double r393428 = r393419 * r393419;
        double r393429 = t;
        double r393430 = a;
        double r393431 = r393429 * r393430;
        double r393432 = r393428 - r393431;
        double r393433 = sqrt(r393432);
        double r393434 = r393419 / r393433;
        double r393435 = r393422 * r393434;
        double r393436 = r393423 * r393435;
        double r393437 = r393427 ? r393436 : r393424;
        double r393438 = r393421 ? r393425 : r393437;
        return r393438;
}

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

Original25.1
Target7.5
Herbie5.9
\[\begin{array}{l} \mathbf{if}\;z \lt -3.1921305903852764 \cdot 10^{46}:\\ \;\;\;\;-y \cdot x\\ \mathbf{elif}\;z \lt 5.9762681209208942 \cdot 10^{90}:\\ \;\;\;\;\frac{x \cdot z}{\frac{\sqrt{z \cdot z - a \cdot t}}{y}}\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array}\]

Derivation

  1. Split input into 3 regimes
  2. if z < -9.341949798077739e+151

    1. Initial program 53.6

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Using strategy rm
    3. Applied *-un-lft-identity53.6

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\sqrt{\color{blue}{1 \cdot \left(z \cdot z - t \cdot a\right)}}}\]
    4. Applied sqrt-prod53.6

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\color{blue}{\sqrt{1} \cdot \sqrt{z \cdot z - t \cdot a}}}\]
    5. Applied times-frac53.2

      \[\leadsto \color{blue}{\frac{x \cdot y}{\sqrt{1}} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}}\]
    6. Simplified53.2

      \[\leadsto \color{blue}{\left(y \cdot x\right)} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\]
    7. Taylor expanded around -inf 1.5

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

    if -9.341949798077739e+151 < z < 2.2349389384476415e+125

    1. Initial program 11.5

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Using strategy rm
    3. Applied *-un-lft-identity11.5

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\sqrt{\color{blue}{1 \cdot \left(z \cdot z - t \cdot a\right)}}}\]
    4. Applied sqrt-prod11.5

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\color{blue}{\sqrt{1} \cdot \sqrt{z \cdot z - t \cdot a}}}\]
    5. Applied times-frac9.3

      \[\leadsto \color{blue}{\frac{x \cdot y}{\sqrt{1}} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}}\]
    6. Simplified9.3

      \[\leadsto \color{blue}{\left(y \cdot x\right)} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\]
    7. Using strategy rm
    8. Applied associate-*l*8.2

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

    if 2.2349389384476415e+125 < z

    1. Initial program 47.2

      \[\frac{\left(x \cdot y\right) \cdot z}{\sqrt{z \cdot z - t \cdot a}}\]
    2. Using strategy rm
    3. Applied *-un-lft-identity47.2

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\sqrt{\color{blue}{1 \cdot \left(z \cdot z - t \cdot a\right)}}}\]
    4. Applied sqrt-prod47.2

      \[\leadsto \frac{\left(x \cdot y\right) \cdot z}{\color{blue}{\sqrt{1} \cdot \sqrt{z \cdot z - t \cdot a}}}\]
    5. Applied times-frac45.4

      \[\leadsto \color{blue}{\frac{x \cdot y}{\sqrt{1}} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}}\]
    6. Simplified45.4

      \[\leadsto \color{blue}{\left(y \cdot x\right)} \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\]
    7. Taylor expanded around inf 1.6

      \[\leadsto \color{blue}{x \cdot y}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification5.9

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \le -9.34194979807773912 \cdot 10^{151}:\\ \;\;\;\;-x \cdot y\\ \mathbf{elif}\;z \le 2.2349389384476415 \cdot 10^{125}:\\ \;\;\;\;y \cdot \left(x \cdot \frac{z}{\sqrt{z \cdot z - t \cdot a}}\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array}\]

Reproduce

herbie shell --seed 2020042 +o rules:numerics
(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)))))