Average Error: 30.6 → 0.3
Time: 1.6s
Precision: binary64
\[\sqrt{x \cdot x + x \cdot x}\]
\[\begin{array}{l} \mathbf{if}\;x \leq 1.2415392020993 \cdot 10^{-310}:\\ \;\;\;\;-x \cdot \sqrt{2}\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot {\left(\sqrt{\sqrt{2}}\right)}^{1.5}\right) \cdot \sqrt{\sqrt{\sqrt{2}}}\\ \end{array}\]
\sqrt{x \cdot x + x \cdot x}
\begin{array}{l}
\mathbf{if}\;x \leq 1.2415392020993 \cdot 10^{-310}:\\
\;\;\;\;-x \cdot \sqrt{2}\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot {\left(\sqrt{\sqrt{2}}\right)}^{1.5}\right) \cdot \sqrt{\sqrt{\sqrt{2}}}\\

\end{array}
(FPCore (x) :precision binary64 (sqrt (+ (* x x) (* x x))))
(FPCore (x)
 :precision binary64
 (if (<= x 1.2415392020993e-310)
   (- (* x (sqrt 2.0)))
   (* (* x (pow (sqrt (sqrt 2.0)) 1.5)) (sqrt (sqrt (sqrt 2.0))))))
double code(double x) {
	return sqrt((x * x) + (x * x));
}
double code(double x) {
	double tmp;
	if (x <= 1.2415392020993e-310) {
		tmp = -(x * sqrt(2.0));
	} else {
		tmp = (x * pow(sqrt(sqrt(2.0)), 1.5)) * sqrt(sqrt(sqrt(2.0)));
	}
	return tmp;
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if x < 1.24153920209931e-310

    1. Initial program 31.0

      \[\sqrt{x \cdot x + x \cdot x}\]
    2. Simplified31.0

      \[\leadsto \color{blue}{\sqrt{x \cdot \left(x + x\right)}}\]
    3. Taylor expanded around -inf 0.4

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \sqrt{2}\right)}\]
    4. Simplified0.4

      \[\leadsto \color{blue}{-x \cdot \sqrt{2}}\]

    if 1.24153920209931e-310 < x

    1. Initial program 30.2

      \[\sqrt{x \cdot x + x \cdot x}\]
    2. Simplified30.1

      \[\leadsto \color{blue}{\sqrt{x \cdot \left(x + x\right)}}\]
    3. Taylor expanded around 0 0.4

      \[\leadsto \color{blue}{x \cdot \sqrt{2}}\]
    4. Using strategy rm
    5. Applied add-sqr-sqrt_binary64_1000.6

      \[\leadsto x \cdot \color{blue}{\left(\sqrt{\sqrt{2}} \cdot \sqrt{\sqrt{2}}\right)}\]
    6. Applied associate-*r*_binary64_180.4

      \[\leadsto \color{blue}{\left(x \cdot \sqrt{\sqrt{2}}\right) \cdot \sqrt{\sqrt{2}}}\]
    7. Using strategy rm
    8. Applied add-sqr-sqrt_binary64_1000.4

      \[\leadsto \left(x \cdot \sqrt{\sqrt{2}}\right) \cdot \color{blue}{\left(\sqrt{\sqrt{\sqrt{2}}} \cdot \sqrt{\sqrt{\sqrt{2}}}\right)}\]
    9. Applied associate-*r*_binary64_180.4

      \[\leadsto \color{blue}{\left(\left(x \cdot \sqrt{\sqrt{2}}\right) \cdot \sqrt{\sqrt{\sqrt{2}}}\right) \cdot \sqrt{\sqrt{\sqrt{2}}}}\]
    10. Simplified0.3

      \[\leadsto \color{blue}{\left(x \cdot {\left(\sqrt{\sqrt{2}}\right)}^{1.5}\right)} \cdot \sqrt{\sqrt{\sqrt{2}}}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.3

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.2415392020993 \cdot 10^{-310}:\\ \;\;\;\;-x \cdot \sqrt{2}\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot {\left(\sqrt{\sqrt{2}}\right)}^{1.5}\right) \cdot \sqrt{\sqrt{\sqrt{2}}}\\ \end{array}\]

Reproduce

herbie shell --seed 2020339 
(FPCore (x)
  :name "sqrt A"
  :precision binary64
  (sqrt (+ (* x x) (* x x))))