Average Error: 20.7 → 0.0
Time: 8.9s
Precision: 64
\[\sqrt{x \cdot x + y}\]
\[\begin{array}{l} \mathbf{if}\;x \le -1.321177529973866349487419790268642426336 \cdot 10^{154}:\\ \;\;\;\;\frac{\frac{-1}{2}}{\frac{x}{y}} - x\\ \mathbf{elif}\;x \le 1.785490461401806573968894092684210024398 \cdot 10^{149}:\\ \;\;\;\;\sqrt{x \cdot x + y}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{x} \cdot \frac{1}{2} + x\\ \end{array}\]
\sqrt{x \cdot x + y}
\begin{array}{l}
\mathbf{if}\;x \le -1.321177529973866349487419790268642426336 \cdot 10^{154}:\\
\;\;\;\;\frac{\frac{-1}{2}}{\frac{x}{y}} - x\\

\mathbf{elif}\;x \le 1.785490461401806573968894092684210024398 \cdot 10^{149}:\\
\;\;\;\;\sqrt{x \cdot x + y}\\

\mathbf{else}:\\
\;\;\;\;\frac{y}{x} \cdot \frac{1}{2} + x\\

\end{array}
double f(double x, double y) {
        double r23108822 = x;
        double r23108823 = r23108822 * r23108822;
        double r23108824 = y;
        double r23108825 = r23108823 + r23108824;
        double r23108826 = sqrt(r23108825);
        return r23108826;
}

double f(double x, double y) {
        double r23108827 = x;
        double r23108828 = -1.3211775299738663e+154;
        bool r23108829 = r23108827 <= r23108828;
        double r23108830 = -0.5;
        double r23108831 = y;
        double r23108832 = r23108827 / r23108831;
        double r23108833 = r23108830 / r23108832;
        double r23108834 = r23108833 - r23108827;
        double r23108835 = 1.7854904614018066e+149;
        bool r23108836 = r23108827 <= r23108835;
        double r23108837 = r23108827 * r23108827;
        double r23108838 = r23108837 + r23108831;
        double r23108839 = sqrt(r23108838);
        double r23108840 = r23108831 / r23108827;
        double r23108841 = 0.5;
        double r23108842 = r23108840 * r23108841;
        double r23108843 = r23108842 + r23108827;
        double r23108844 = r23108836 ? r23108839 : r23108843;
        double r23108845 = r23108829 ? r23108834 : r23108844;
        return r23108845;
}

Error

Bits error versus x

Bits error versus y

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original20.7
Target0.6
Herbie0.0
\[\begin{array}{l} \mathbf{if}\;x \lt -1.509769801047259255153812752081023359759 \cdot 10^{153}:\\ \;\;\;\;-\left(0.5 \cdot \frac{y}{x} + x\right)\\ \mathbf{elif}\;x \lt 5.582399551122540716781541767466805967807 \cdot 10^{57}:\\ \;\;\;\;\sqrt{x \cdot x + y}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \frac{y}{x} + x\\ \end{array}\]

Derivation

  1. Split input into 3 regimes
  2. if x < -1.3211775299738663e+154

    1. Initial program 64.0

      \[\sqrt{x \cdot x + y}\]
    2. Taylor expanded around -inf 0

      \[\leadsto \color{blue}{-\left(x + \frac{1}{2} \cdot \frac{y}{x}\right)}\]
    3. Simplified0

      \[\leadsto \color{blue}{\frac{\frac{-1}{2}}{\frac{x}{y}} - x}\]

    if -1.3211775299738663e+154 < x < 1.7854904614018066e+149

    1. Initial program 0.0

      \[\sqrt{x \cdot x + y}\]

    if 1.7854904614018066e+149 < x

    1. Initial program 61.8

      \[\sqrt{x \cdot x + y}\]
    2. Taylor expanded around inf 0.0

      \[\leadsto \color{blue}{x + \frac{1}{2} \cdot \frac{y}{x}}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification0.0

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -1.321177529973866349487419790268642426336 \cdot 10^{154}:\\ \;\;\;\;\frac{\frac{-1}{2}}{\frac{x}{y}} - x\\ \mathbf{elif}\;x \le 1.785490461401806573968894092684210024398 \cdot 10^{149}:\\ \;\;\;\;\sqrt{x \cdot x + y}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{x} \cdot \frac{1}{2} + x\\ \end{array}\]

Reproduce

herbie shell --seed 2019179 
(FPCore (x y)
  :name "Linear.Quaternion:$clog from linear-1.19.1.3"

  :herbie-target
  (if (< x -1.5097698010472593e+153) (- (+ (* 0.5 (/ y x)) x)) (if (< x 5.582399551122541e+57) (sqrt (+ (* x x) y)) (+ (* 0.5 (/ y x)) x)))

  (sqrt (+ (* x x) y)))