math.sqrt on complex, real part

Percentage Accurate: 40.9% → 83.4%

Time: 7.6s

Alternatives: 8

Speedup: 1.7×

Specification

Math

\[\begin{array}{l} \\ 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (* 0.5 (sqrt (* 2.0 (+ (sqrt (+ (* re re) (* im im))) re)))))

C

double code(double re, double im) {
	return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) + re)));
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = 0.5d0 * sqrt((2.0d0 * (sqrt(((re * re) + (im * im))) + re)))
end function

Java

public static double code(double re, double im) {
	return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) + re)));
}

Python

def code(re, im):
	return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) + re)))

Julia

function code(re, im)
	return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) + re))))
end

MATLAB

function tmp = code(re, im)
	tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) + re)));
end

Wolfram

code[re_, im_] := N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

Initial Program: 40.9% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (* 0.5 (sqrt (* 2.0 (+ (sqrt (+ (* re re) (* im im))) re)))))

C

double code(double re, double im) {
	return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) + re)));
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = 0.5d0 * sqrt((2.0d0 * (sqrt(((re * re) + (im * im))) + re)))
end function

Java

public static double code(double re, double im) {
	return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) + re)));
}

Python

def code(re, im):
	return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) + re)))

Julia

function code(re, im)
	return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) + re))))
end

MATLAB

function tmp = code(re, im)
	tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) + re)));
end

Wolfram

code[re_, im_] := N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

Alternative 1: 83.4% accurate, 0.1× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -1.6 \cdot 10^{+92}:\\ \;\;\;\;e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, -0.25, \log \left(im \cdot im\right) + \log \left(\frac{-1}{re}\right)\right) \cdot 0.5} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -1.6e+92)
   (*
    (exp
     (*
      (fma (* (/ im re) (/ im re)) -0.25 (+ (log (* im im)) (log (/ -1.0 re))))
      0.5))
    0.5)
   (* (sqrt (* (+ (hypot im re) re) 2.0)) 0.5)))

C

double code(double re, double im) {
	double tmp;
	if (re <= -1.6e+92) {
		tmp = exp((fma(((im / re) * (im / re)), -0.25, (log((im * im)) + log((-1.0 / re)))) * 0.5)) * 0.5;
	} else {
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -1.6e+92)
		tmp = Float64(exp(Float64(fma(Float64(Float64(im / re) * Float64(im / re)), -0.25, Float64(log(Float64(im * im)) + log(Float64(-1.0 / re)))) * 0.5)) * 0.5);
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end

Wolfram

code[re_, im_] := If[LessEqual[re, -1.6e+92], N[(N[Exp[N[(N[(N[(N[(im / re), $MachinePrecision] * N[(im / re), $MachinePrecision]), $MachinePrecision] * -0.25 + N[(N[Log[N[(im * im), $MachinePrecision]], $MachinePrecision] + N[Log[N[(-1.0 / re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if re < -1.60000000000000013e92

   1. Initial program 5.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 5.5

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 5.5

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 33.8

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 33.8%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
   5. Step-by-step derivation

      1. lift-sqrt.f64 N/A

         \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      2. pow1/2 N/A

         \[\leadsto \color{blue}{{\left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right)}^{\frac{1}{2}}} \cdot \frac{1}{2} \]

      3. lift-*.f64 N/A

         \[\leadsto {\color{blue}{\left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      4. *-commutative N/A

         \[\leadsto {\color{blue}{\left(2 \cdot \left(\mathsf{hypot}\left(im, re\right) + re\right)\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      5. lift-+.f64 N/A

         \[\leadsto {\left(2 \cdot \color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right)}\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      6. lift-+.f64 N/A

         \[\leadsto {\left(2 \cdot \color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right)}\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      7. lift-hypot.f64 N/A

         \[\leadsto {\left(2 \cdot \left(\color{blue}{\sqrt{im \cdot im + re \cdot re}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      8. lift-*.f64 N/A

         \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      10. lift-fma.f64 N/A

          \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      11. lift-sqrt.f64 N/A

          \[\leadsto {\left(2 \cdot \left(\color{blue}{\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      12. lift-*.f64 N/A

          \[\leadsto {\color{blue}{\left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      13. pow-to-exp N/A

          \[\leadsto \color{blue}{e^{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

      14. lower-exp.f64 N/A

          \[\leadsto \color{blue}{e^{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

      15. lower-*.f64 N/A

          \[\leadsto e^{\color{blue}{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

   6. Applied rewrites 32.5%

      \[\leadsto \color{blue}{e^{\log \left(\left(\mathsf{hypot}\left(re, im\right) + re\right) \cdot 2\right) \cdot 0.5}} \cdot 0.5 \]

   7. Taylor expanded in re around -inf

      \[\leadsto e^{\color{blue}{\left(\log \left(\frac{-1}{re}\right) + \left(\log \left({im}^{2}\right) + \frac{-1}{4} \cdot \frac{{im}^{2}}{{re}^{2}}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]
   8. Step-by-step derivation

      1. +-commutative N/A

         \[\leadsto e^{\color{blue}{\left(\left(\log \left({im}^{2}\right) + \frac{-1}{4} \cdot \frac{{im}^{2}}{{re}^{2}}\right) + \log \left(\frac{-1}{re}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      2. +-commutative N/A

         \[\leadsto e^{\left(\color{blue}{\left(\frac{-1}{4} \cdot \frac{{im}^{2}}{{re}^{2}} + \log \left({im}^{2}\right)\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      3. associate-+l+ N/A

         \[\leadsto e^{\color{blue}{\left(\frac{-1}{4} \cdot \frac{{im}^{2}}{{re}^{2}} + \left(\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      4. *-commutative N/A

         \[\leadsto e^{\left(\color{blue}{\frac{{im}^{2}}{{re}^{2}} \cdot \frac{-1}{4}} + \left(\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      5. +-commutative N/A

         \[\leadsto e^{\left(\frac{{im}^{2}}{{re}^{2}} \cdot \frac{-1}{4} + \color{blue}{\left(\log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right)}\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      6. lower-fma.f64 N/A

         \[\leadsto e^{\color{blue}{\mathsf{fma}\left(\frac{{im}^{2}}{{re}^{2}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      7. unpow2 N/A

         \[\leadsto e^{\mathsf{fma}\left(\frac{\color{blue}{im \cdot im}}{{re}^{2}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      8. unpow2 N/A

         \[\leadsto e^{\mathsf{fma}\left(\frac{im \cdot im}{\color{blue}{re \cdot re}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      9. times-frac N/A

         \[\leadsto e^{\mathsf{fma}\left(\color{blue}{\frac{im}{re} \cdot \frac{im}{re}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      10. lower-*.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\color{blue}{\frac{im}{re} \cdot \frac{im}{re}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      11. lower-/.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\color{blue}{\frac{im}{re}} \cdot \frac{im}{re}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      12. lower-/.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \color{blue}{\frac{im}{re}}, \frac{-1}{4}, \log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      13. +-commutative N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \color{blue}{\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)}\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      14. lower-+.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \color{blue}{\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)}\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      15. lower-log.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \color{blue}{\log \left({im}^{2}\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      16. unpow2 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \log \color{blue}{\left(im \cdot im\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      17. lower-*.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \log \color{blue}{\left(im \cdot im\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      18. lower-log.f64 N/A

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, \frac{-1}{4}, \log \left(im \cdot im\right) + \color{blue}{\log \left(\frac{-1}{re}\right)}\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      19. lower-/.f64 66.7

          \[\leadsto e^{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, -0.25, \log \left(im \cdot im\right) + \log \color{blue}{\left(\frac{-1}{re}\right)}\right) \cdot 0.5} \cdot 0.5 \]

   9. Applied rewrites 66.7%

      \[\leadsto e^{\color{blue}{\mathsf{fma}\left(\frac{im}{re} \cdot \frac{im}{re}, -0.25, \log \left(im \cdot im\right) + \log \left(\frac{-1}{re}\right)\right)} \cdot 0.5} \cdot 0.5 \]

   if -1.60000000000000013e92 < re

   1. Initial program 46.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 46.2

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 46.2

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 90.4

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 90.4%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 2: 83.5% accurate, 0.1× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -1.6 \cdot 10^{+92}:\\ \;\;\;\;e^{\left(\log \left(im \cdot im\right) + \log \left(\frac{-1}{re}\right)\right) \cdot 0.5} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -1.6e+92)
   (* (exp (* (+ (log (* im im)) (log (/ -1.0 re))) 0.5)) 0.5)
   (* (sqrt (* (+ (hypot im re) re) 2.0)) 0.5)))

C

double code(double re, double im) {
	double tmp;
	if (re <= -1.6e+92) {
		tmp = exp(((log((im * im)) + log((-1.0 / re))) * 0.5)) * 0.5;
	} else {
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Java

public static double code(double re, double im) {
	double tmp;
	if (re <= -1.6e+92) {
		tmp = Math.exp(((Math.log((im * im)) + Math.log((-1.0 / re))) * 0.5)) * 0.5;
	} else {
		tmp = Math.sqrt(((Math.hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Python

def code(re, im):
	tmp = 0
	if re <= -1.6e+92:
		tmp = math.exp(((math.log((im * im)) + math.log((-1.0 / re))) * 0.5)) * 0.5
	else:
		tmp = math.sqrt(((math.hypot(im, re) + re) * 2.0)) * 0.5
	return tmp

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -1.6e+92)
		tmp = Float64(exp(Float64(Float64(log(Float64(im * im)) + log(Float64(-1.0 / re))) * 0.5)) * 0.5);
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -1.6e+92)
		tmp = exp(((log((im * im)) + log((-1.0 / re))) * 0.5)) * 0.5;
	else
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := If[LessEqual[re, -1.6e+92], N[(N[Exp[N[(N[(N[Log[N[(im * im), $MachinePrecision]], $MachinePrecision] + N[Log[N[(-1.0 / re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if re < -1.60000000000000013e92

   1. Initial program 5.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 5.5

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 5.5

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 33.8

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 33.8%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
   5. Step-by-step derivation

      1. lift-sqrt.f64 N/A

         \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      2. pow1/2 N/A

         \[\leadsto \color{blue}{{\left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right)}^{\frac{1}{2}}} \cdot \frac{1}{2} \]

      3. lift-*.f64 N/A

         \[\leadsto {\color{blue}{\left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      4. *-commutative N/A

         \[\leadsto {\color{blue}{\left(2 \cdot \left(\mathsf{hypot}\left(im, re\right) + re\right)\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      5. lift-+.f64 N/A

         \[\leadsto {\left(2 \cdot \color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right)}\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      6. lift-+.f64 N/A

         \[\leadsto {\left(2 \cdot \color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right)}\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      7. lift-hypot.f64 N/A

         \[\leadsto {\left(2 \cdot \left(\color{blue}{\sqrt{im \cdot im + re \cdot re}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      8. lift-*.f64 N/A

         \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      10. lift-fma.f64 N/A

          \[\leadsto {\left(2 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      11. lift-sqrt.f64 N/A

          \[\leadsto {\left(2 \cdot \left(\color{blue}{\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)\right)}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      12. lift-*.f64 N/A

          \[\leadsto {\color{blue}{\left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right)}}^{\frac{1}{2}} \cdot \frac{1}{2} \]

      13. pow-to-exp N/A

          \[\leadsto \color{blue}{e^{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

      14. lower-exp.f64 N/A

          \[\leadsto \color{blue}{e^{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

      15. lower-*.f64 N/A

          \[\leadsto e^{\color{blue}{\log \left(2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)\right) \cdot \frac{1}{2}}} \cdot \frac{1}{2} \]

   6. Applied rewrites 32.5%

      \[\leadsto \color{blue}{e^{\log \left(\left(\mathsf{hypot}\left(re, im\right) + re\right) \cdot 2\right) \cdot 0.5}} \cdot 0.5 \]

   7. Taylor expanded in re around -inf

      \[\leadsto e^{\color{blue}{\left(\log \left(\frac{-1}{re}\right) + \log \left({im}^{2}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]
   8. Step-by-step derivation

      1. +-commutative N/A

         \[\leadsto e^{\color{blue}{\left(\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      2. lower-+.f64 N/A

         \[\leadsto e^{\color{blue}{\left(\log \left({im}^{2}\right) + \log \left(\frac{-1}{re}\right)\right)} \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      3. lower-log.f64 N/A

         \[\leadsto e^{\left(\color{blue}{\log \left({im}^{2}\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      4. unpow2 N/A

         \[\leadsto e^{\left(\log \color{blue}{\left(im \cdot im\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      5. lower-*.f64 N/A

         \[\leadsto e^{\left(\log \color{blue}{\left(im \cdot im\right)} + \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      6. lower-log.f64 N/A

         \[\leadsto e^{\left(\log \left(im \cdot im\right) + \color{blue}{\log \left(\frac{-1}{re}\right)}\right) \cdot \frac{1}{2}} \cdot \frac{1}{2} \]

      7. lower-/.f64 66.1

         \[\leadsto e^{\left(\log \left(im \cdot im\right) + \log \color{blue}{\left(\frac{-1}{re}\right)}\right) \cdot 0.5} \cdot 0.5 \]

   9. Applied rewrites 66.1%

      \[\leadsto e^{\color{blue}{\left(\log \left(im \cdot im\right) + \log \left(\frac{-1}{re}\right)\right)} \cdot 0.5} \cdot 0.5 \]

   if -1.60000000000000013e92 < re

   1. Initial program 46.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 46.2

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 46.2

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 90.4

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 90.4%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 3: 82.3% accurate, 0.3× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -6.8 \cdot 10^{+31}:\\ \;\;\;\;\sqrt{\frac{-2 \cdot \left(im \cdot im\right)}{re - \mathsf{hypot}\left(re, im\right)}} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -6.8e+31)
   (* (sqrt (/ (* -2.0 (* im im)) (- re (hypot re im)))) 0.5)
   (* (sqrt (* (+ (hypot im re) re) 2.0)) 0.5)))

C

double code(double re, double im) {
	double tmp;
	if (re <= -6.8e+31) {
		tmp = sqrt(((-2.0 * (im * im)) / (re - hypot(re, im)))) * 0.5;
	} else {
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Java

public static double code(double re, double im) {
	double tmp;
	if (re <= -6.8e+31) {
		tmp = Math.sqrt(((-2.0 * (im * im)) / (re - Math.hypot(re, im)))) * 0.5;
	} else {
		tmp = Math.sqrt(((Math.hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Python

def code(re, im):
	tmp = 0
	if re <= -6.8e+31:
		tmp = math.sqrt(((-2.0 * (im * im)) / (re - math.hypot(re, im)))) * 0.5
	else:
		tmp = math.sqrt(((math.hypot(im, re) + re) * 2.0)) * 0.5
	return tmp

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -6.8e+31)
		tmp = Float64(sqrt(Float64(Float64(-2.0 * Float64(im * im)) / Float64(re - hypot(re, im)))) * 0.5);
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -6.8e+31)
		tmp = sqrt(((-2.0 * (im * im)) / (re - hypot(re, im)))) * 0.5;
	else
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := If[LessEqual[re, -6.8e+31], N[(N[Sqrt[N[(N[(-2.0 * N[(im * im), $MachinePrecision]), $MachinePrecision] / N[(re - N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if re < -6.7999999999999996e31

   1. Initial program 10.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 10.2

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 10.2

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 36.6

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 36.6%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
   5. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      2. lift-+.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\left(\mathsf{hypot}\left(im, re\right) + re\right)} \cdot 2} \cdot \frac{1}{2} \]

      3. +-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(re + \mathsf{hypot}\left(im, re\right)\right)} \cdot 2} \cdot \frac{1}{2} \]

      4. flip-+ N/A

         \[\leadsto \sqrt{\color{blue}{\frac{re \cdot re - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)}{re - \mathsf{hypot}\left(im, re\right)}} \cdot 2} \cdot \frac{1}{2} \]

      5. associate-*l/ N/A

         \[\leadsto \sqrt{\color{blue}{\frac{\left(re \cdot re - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}}} \cdot \frac{1}{2} \]

      6. lower-/.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\frac{\left(re \cdot re - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}}} \cdot \frac{1}{2} \]

      7. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(re \cdot re - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)\right) \cdot 2}}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      8. lower--.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(re \cdot re - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)\right)} \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      9. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\left(\color{blue}{re \cdot re} - \mathsf{hypot}\left(im, re\right) \cdot \mathsf{hypot}\left(im, re\right)\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      10. pow2 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - \color{blue}{{\left(\mathsf{hypot}\left(im, re\right)\right)}^{2}}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      11. lower-pow.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - \color{blue}{{\left(\mathsf{hypot}\left(im, re\right)\right)}^{2}}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      12. lift-hypot.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\color{blue}{\left(\sqrt{im \cdot im + re \cdot re}\right)}}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      13. lift-*.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re}\right)}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      14. +-commutative N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}}\right)}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      15. lift-*.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\sqrt{re \cdot re + \color{blue}{im \cdot im}}\right)}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      16. lower-hypot.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\color{blue}{\left(\mathsf{hypot}\left(re, im\right)\right)}}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(im, re\right)}} \cdot \frac{1}{2} \]

      17. lower--.f64 8.6

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{\color{blue}{re - \mathsf{hypot}\left(im, re\right)}}} \cdot 0.5 \]

      18. lift-hypot.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{re - \color{blue}{\sqrt{im \cdot im + re \cdot re}}}} \cdot \frac{1}{2} \]

      19. lift-*.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{re - \sqrt{\color{blue}{im \cdot im} + re \cdot re}}} \cdot \frac{1}{2} \]

      20. +-commutative N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{re - \sqrt{\color{blue}{re \cdot re + im \cdot im}}}} \cdot \frac{1}{2} \]

      21. lift-*.f64 N/A

          \[\leadsto \sqrt{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{re - \sqrt{re \cdot re + \color{blue}{im \cdot im}}}} \cdot \frac{1}{2} \]

   6. Applied rewrites 8.6%

      \[\leadsto \sqrt{\color{blue}{\frac{\left(re \cdot re - {\left(\mathsf{hypot}\left(re, im\right)\right)}^{2}\right) \cdot 2}{re - \mathsf{hypot}\left(re, im\right)}}} \cdot 0.5 \]

   7. Taylor expanded in re around 0

      \[\leadsto \sqrt{\frac{\color{blue}{-2 \cdot {im}^{2}}}{re - \mathsf{hypot}\left(re, im\right)}} \cdot \frac{1}{2} \]
   8. Step-by-step derivation

      1. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{-2 \cdot {im}^{2}}}{re - \mathsf{hypot}\left(re, im\right)}} \cdot \frac{1}{2} \]

      2. unpow2 N/A

         \[\leadsto \sqrt{\frac{-2 \cdot \color{blue}{\left(im \cdot im\right)}}{re - \mathsf{hypot}\left(re, im\right)}} \cdot \frac{1}{2} \]

      3. lower-*.f64 61.8

         \[\leadsto \sqrt{\frac{-2 \cdot \color{blue}{\left(im \cdot im\right)}}{re - \mathsf{hypot}\left(re, im\right)}} \cdot 0.5 \]

   9. Applied rewrites 61.8%

      \[\leadsto \sqrt{\frac{\color{blue}{-2 \cdot \left(im \cdot im\right)}}{re - \mathsf{hypot}\left(re, im\right)}} \cdot 0.5 \]

   if -6.7999999999999996e31 < re

   1. Initial program 47.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 47.0

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 47.0

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 92.7

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 92.7%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 4: 81.3% accurate, 0.4× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -1.6 \cdot 10^{+92}:\\ \;\;\;\;\sqrt{\frac{\left(-im\right) \cdot im}{re}} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -1.6e+92)
   (* (sqrt (/ (* (- im) im) re)) 0.5)
   (* (sqrt (* (+ (hypot im re) re) 2.0)) 0.5)))

C

double code(double re, double im) {
	double tmp;
	if (re <= -1.6e+92) {
		tmp = sqrt(((-im * im) / re)) * 0.5;
	} else {
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Java

public static double code(double re, double im) {
	double tmp;
	if (re <= -1.6e+92) {
		tmp = Math.sqrt(((-im * im) / re)) * 0.5;
	} else {
		tmp = Math.sqrt(((Math.hypot(im, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}

Python

def code(re, im):
	tmp = 0
	if re <= -1.6e+92:
		tmp = math.sqrt(((-im * im) / re)) * 0.5
	else:
		tmp = math.sqrt(((math.hypot(im, re) + re) * 2.0)) * 0.5
	return tmp

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -1.6e+92)
		tmp = Float64(sqrt(Float64(Float64(Float64(-im) * im) / re)) * 0.5);
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -1.6e+92)
		tmp = sqrt(((-im * im) / re)) * 0.5;
	else
		tmp = sqrt(((hypot(im, re) + re) * 2.0)) * 0.5;
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := If[LessEqual[re, -1.6e+92], N[(N[Sqrt[N[(N[((-im) * im), $MachinePrecision] / re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if re < -1.60000000000000013e92

   1. Initial program 5.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 5.5

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 5.5

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 33.8

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 33.8%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]

   5. Taylor expanded in re around -inf

      \[\leadsto \sqrt{\color{blue}{-1 \cdot \frac{{im}^{2}}{re}}} \cdot \frac{1}{2} \]
   6. Step-by-step derivation

      1. associate-*r/ N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      2. lower-/.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      3. unpow2 N/A

         \[\leadsto \sqrt{\frac{-1 \cdot \color{blue}{\left(im \cdot im\right)}}{re}} \cdot \frac{1}{2} \]

      4. associate-*r* N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      5. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      6. mul-1-neg N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(\mathsf{neg}\left(im\right)\right)} \cdot im}{re}} \cdot \frac{1}{2} \]

      7. lower-neg.f64 61.4

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-im\right)} \cdot im}{re}} \cdot 0.5 \]

   7. Applied rewrites 61.4%

      \[\leadsto \sqrt{\color{blue}{\frac{\left(-im\right) \cdot im}{re}}} \cdot 0.5 \]

   if -1.60000000000000013e92 < re

   1. Initial program 46.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 46.2

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 46.2

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 90.4

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 90.4%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 5: 54.9% accurate, 0.7× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -1.08 \cdot 10^{+48}:\\ \;\;\;\;\sqrt{\frac{\left(-im\right) \cdot im}{re}} \cdot 0.5\\ \mathbf{elif}\;re \leq 1.7 \cdot 10^{-145}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, 2 \cdot im\right)} \cdot 0.5\\ \mathbf{elif}\;re \leq 1.75 \cdot 10^{+33}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} + re\right)}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{re}\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -1.08e+48)
   (* (sqrt (/ (* (- im) im) re)) 0.5)
   (if (<= re 1.7e-145)
     (* (sqrt (fma (+ (/ re im) 2.0) re (* 2.0 im))) 0.5)
     (if (<= re 1.75e+33)
       (* 0.5 (sqrt (* 2.0 (+ (sqrt (fma re re (* im im))) re))))
       (sqrt re)))))

C

double code(double re, double im) {
	double tmp;
	if (re <= -1.08e+48) {
		tmp = sqrt(((-im * im) / re)) * 0.5;
	} else if (re <= 1.7e-145) {
		tmp = sqrt(fma(((re / im) + 2.0), re, (2.0 * im))) * 0.5;
	} else if (re <= 1.75e+33) {
		tmp = 0.5 * sqrt((2.0 * (sqrt(fma(re, re, (im * im))) + re)));
	} else {
		tmp = sqrt(re);
	}
	return tmp;
}

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -1.08e+48)
		tmp = Float64(sqrt(Float64(Float64(Float64(-im) * im) / re)) * 0.5);
	elseif (re <= 1.7e-145)
		tmp = Float64(sqrt(fma(Float64(Float64(re / im) + 2.0), re, Float64(2.0 * im))) * 0.5);
	elseif (re <= 1.75e+33)
		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(fma(re, re, Float64(im * im))) + re))));
	else
		tmp = sqrt(re);
	end
	return tmp
end

Wolfram

code[re_, im_] := If[LessEqual[re, -1.08e+48], N[(N[Sqrt[N[(N[((-im) * im), $MachinePrecision] / re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 1.7e-145], N[(N[Sqrt[N[(N[(N[(re / im), $MachinePrecision] + 2.0), $MachinePrecision] * re + N[(2.0 * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 1.75e+33], N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[N[(re * re + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[re], $MachinePrecision]]]]

Derivation

1. Split input into 4 regimes

2. if re < -1.07999999999999998e48

   1. Initial program 8.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 8.9

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 8.9

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 35.0

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 35.0%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]

   5. Taylor expanded in re around -inf

      \[\leadsto \sqrt{\color{blue}{-1 \cdot \frac{{im}^{2}}{re}}} \cdot \frac{1}{2} \]
   6. Step-by-step derivation

      1. associate-*r/ N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      2. lower-/.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      3. unpow2 N/A

         \[\leadsto \sqrt{\frac{-1 \cdot \color{blue}{\left(im \cdot im\right)}}{re}} \cdot \frac{1}{2} \]

      4. associate-*r* N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      5. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      6. mul-1-neg N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(\mathsf{neg}\left(im\right)\right)} \cdot im}{re}} \cdot \frac{1}{2} \]

      7. lower-neg.f64 57.9

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-im\right)} \cdot im}{re}} \cdot 0.5 \]

   7. Applied rewrites 57.9%

      \[\leadsto \sqrt{\color{blue}{\frac{\left(-im\right) \cdot im}{re}}} \cdot 0.5 \]

   if -1.07999999999999998e48 < re < 1.6999999999999999e-145

   1. Initial program 44.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 44.5

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 44.5

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 85.5

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 85.5%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]

   5. Taylor expanded in re around 0

      \[\leadsto \sqrt{\color{blue}{2 \cdot im + re \cdot \left(2 + \frac{re}{im}\right)}} \cdot \frac{1}{2} \]
   6. Step-by-step derivation

      1. +-commutative N/A

         \[\leadsto \sqrt{\color{blue}{re \cdot \left(2 + \frac{re}{im}\right) + 2 \cdot im}} \cdot \frac{1}{2} \]

      2. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(2 + \frac{re}{im}\right) \cdot re} + 2 \cdot im} \cdot \frac{1}{2} \]

      3. lower-fma.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(2 + \frac{re}{im}, re, 2 \cdot im\right)}} \cdot \frac{1}{2} \]

      4. +-commutative N/A

         \[\leadsto \sqrt{\mathsf{fma}\left(\color{blue}{\frac{re}{im} + 2}, re, 2 \cdot im\right)} \cdot \frac{1}{2} \]

      5. lower-+.f64 N/A

         \[\leadsto \sqrt{\mathsf{fma}\left(\color{blue}{\frac{re}{im} + 2}, re, 2 \cdot im\right)} \cdot \frac{1}{2} \]

      6. lower-/.f64 N/A

         \[\leadsto \sqrt{\mathsf{fma}\left(\color{blue}{\frac{re}{im}} + 2, re, 2 \cdot im\right)} \cdot \frac{1}{2} \]

      7. lower-*.f64 43.6

         \[\leadsto \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, \color{blue}{2 \cdot im}\right)} \cdot 0.5 \]

   7. Applied rewrites 43.6%

      \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{re}{im} + 2, re, 2 \cdot im\right)}} \cdot 0.5 \]

   if 1.6999999999999999e-145 < re < 1.75000000000000005e33

   1. Initial program 88.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-+.f64 N/A

         \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right)} \]

      2. lift-*.f64 N/A

         \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{re \cdot re} + im \cdot im} + re\right)} \]

      3. lower-fma.f64 88.0

         \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)} \]

   4. Applied rewrites 88.0%

      \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(re, re, im \cdot im\right)}} + re\right)} \]

   if 1.75000000000000005e33 < re

   1. Initial program 29.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing

   3. Taylor expanded in re around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
   4. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({\left(\sqrt{2}\right)}^{2} \cdot \sqrt{re}\right)} \]

      2. associate-*r* N/A

         \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {\left(\sqrt{2}\right)}^{2}\right) \cdot \sqrt{re}} \]

      3. unpow2 N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \sqrt{2}\right)}\right) \cdot \sqrt{re} \]

      4. rem-square-sqrt N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{2}\right) \cdot \sqrt{re} \]

      5. metadata-eval N/A

         \[\leadsto \color{blue}{1} \cdot \sqrt{re} \]

      6. *-lft-identity N/A

         \[\leadsto \color{blue}{\sqrt{re}} \]

      7. lower-sqrt.f64 77.0

         \[\leadsto \color{blue}{\sqrt{re}} \]

   5. Applied rewrites 77.0%

      \[\leadsto \color{blue}{\sqrt{re}} \]
3. Recombined 4 regimes into one program.
4. Add Preprocessing

Alternative 6: 47.0% accurate, 1.2× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+47}:\\ \;\;\;\;\sqrt{\frac{\left(-im\right) \cdot im}{re}} \cdot 0.5\\ \mathbf{elif}\;re \leq 1.12 \cdot 10^{+130}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im + re\right)}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{re}\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re -4.8e+47)
   (* (sqrt (/ (* (- im) im) re)) 0.5)
   (if (<= re 1.12e+130) (* 0.5 (sqrt (* 2.0 (+ im re)))) (sqrt re))))

C

double code(double re, double im) {
	double tmp;
	if (re <= -4.8e+47) {
		tmp = sqrt(((-im * im) / re)) * 0.5;
	} else if (re <= 1.12e+130) {
		tmp = 0.5 * sqrt((2.0 * (im + re)));
	} else {
		tmp = sqrt(re);
	}
	return tmp;
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if (re <= (-4.8d+47)) then
        tmp = sqrt(((-im * im) / re)) * 0.5d0
    else if (re <= 1.12d+130) then
        tmp = 0.5d0 * sqrt((2.0d0 * (im + re)))
    else
        tmp = sqrt(re)
    end if
    code = tmp
end function

Java

public static double code(double re, double im) {
	double tmp;
	if (re <= -4.8e+47) {
		tmp = Math.sqrt(((-im * im) / re)) * 0.5;
	} else if (re <= 1.12e+130) {
		tmp = 0.5 * Math.sqrt((2.0 * (im + re)));
	} else {
		tmp = Math.sqrt(re);
	}
	return tmp;
}

Python

def code(re, im):
	tmp = 0
	if re <= -4.8e+47:
		tmp = math.sqrt(((-im * im) / re)) * 0.5
	elif re <= 1.12e+130:
		tmp = 0.5 * math.sqrt((2.0 * (im + re)))
	else:
		tmp = math.sqrt(re)
	return tmp

Julia

function code(re, im)
	tmp = 0.0
	if (re <= -4.8e+47)
		tmp = Float64(sqrt(Float64(Float64(Float64(-im) * im) / re)) * 0.5);
	elseif (re <= 1.12e+130)
		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(im + re))));
	else
		tmp = sqrt(re);
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -4.8e+47)
		tmp = sqrt(((-im * im) / re)) * 0.5;
	elseif (re <= 1.12e+130)
		tmp = 0.5 * sqrt((2.0 * (im + re)));
	else
		tmp = sqrt(re);
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := If[LessEqual[re, -4.8e+47], N[(N[Sqrt[N[(N[((-im) * im), $MachinePrecision] / re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 1.12e+130], N[(0.5 * N[Sqrt[N[(2.0 * N[(im + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[re], $MachinePrecision]]]

Derivation

1. Split input into 3 regimes

2. if re < -4.80000000000000037e47

   1. Initial program 8.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 8.9

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 8.9

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 35.0

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 35.0%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]

   5. Taylor expanded in re around -inf

      \[\leadsto \sqrt{\color{blue}{-1 \cdot \frac{{im}^{2}}{re}}} \cdot \frac{1}{2} \]
   6. Step-by-step derivation

      1. associate-*r/ N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      2. lower-/.f64 N/A

         \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot {im}^{2}}{re}}} \cdot \frac{1}{2} \]

      3. unpow2 N/A

         \[\leadsto \sqrt{\frac{-1 \cdot \color{blue}{\left(im \cdot im\right)}}{re}} \cdot \frac{1}{2} \]

      4. associate-*r* N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      5. lower-*.f64 N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-1 \cdot im\right) \cdot im}}{re}} \cdot \frac{1}{2} \]

      6. mul-1-neg N/A

         \[\leadsto \sqrt{\frac{\color{blue}{\left(\mathsf{neg}\left(im\right)\right)} \cdot im}{re}} \cdot \frac{1}{2} \]

      7. lower-neg.f64 57.9

         \[\leadsto \sqrt{\frac{\color{blue}{\left(-im\right)} \cdot im}{re}} \cdot 0.5 \]

   7. Applied rewrites 57.9%

      \[\leadsto \sqrt{\color{blue}{\frac{\left(-im\right) \cdot im}{re}}} \cdot 0.5 \]

   if -4.80000000000000037e47 < re < 1.1199999999999999e130

   1. Initial program 54.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing

   3. Taylor expanded in re around 0

      \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(im + re\right)}} \]
   4. Step-by-step derivation

      1. lower-+.f64 40.7

         \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im + re\right)}} \]

   5. Applied rewrites 40.7%

      \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im + re\right)}} \]

   if 1.1199999999999999e130 < re

   1. Initial program 22.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing

   3. Taylor expanded in re around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
   4. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({\left(\sqrt{2}\right)}^{2} \cdot \sqrt{re}\right)} \]

      2. associate-*r* N/A

         \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {\left(\sqrt{2}\right)}^{2}\right) \cdot \sqrt{re}} \]

      3. unpow2 N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \sqrt{2}\right)}\right) \cdot \sqrt{re} \]

      4. rem-square-sqrt N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{2}\right) \cdot \sqrt{re} \]

      5. metadata-eval N/A

         \[\leadsto \color{blue}{1} \cdot \sqrt{re} \]

      6. *-lft-identity N/A

         \[\leadsto \color{blue}{\sqrt{re}} \]

      7. lower-sqrt.f64 84.1

         \[\leadsto \color{blue}{\sqrt{re}} \]

   5. Applied rewrites 84.1%

      \[\leadsto \color{blue}{\sqrt{re}} \]
3. Recombined 3 regimes into one program.
4. Add Preprocessing

Alternative 7: 42.7% accurate, 1.7× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq 2.15 \cdot 10^{-132}:\\ \;\;\;\;\sqrt{2 \cdot im} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{re}\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (if (<= re 2.15e-132) (* (sqrt (* 2.0 im)) 0.5) (sqrt re)))

C

double code(double re, double im) {
	double tmp;
	if (re <= 2.15e-132) {
		tmp = sqrt((2.0 * im)) * 0.5;
	} else {
		tmp = sqrt(re);
	}
	return tmp;
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if (re <= 2.15d-132) then
        tmp = sqrt((2.0d0 * im)) * 0.5d0
    else
        tmp = sqrt(re)
    end if
    code = tmp
end function

Java

public static double code(double re, double im) {
	double tmp;
	if (re <= 2.15e-132) {
		tmp = Math.sqrt((2.0 * im)) * 0.5;
	} else {
		tmp = Math.sqrt(re);
	}
	return tmp;
}

Python

def code(re, im):
	tmp = 0
	if re <= 2.15e-132:
		tmp = math.sqrt((2.0 * im)) * 0.5
	else:
		tmp = math.sqrt(re)
	return tmp

Julia

function code(re, im)
	tmp = 0.0
	if (re <= 2.15e-132)
		tmp = Float64(sqrt(Float64(2.0 * im)) * 0.5);
	else
		tmp = sqrt(re);
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= 2.15e-132)
		tmp = sqrt((2.0 * im)) * 0.5;
	else
		tmp = sqrt(re);
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := If[LessEqual[re, 2.15e-132], N[(N[Sqrt[N[(2.0 * im), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[Sqrt[re], $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if re < 2.1499999999999998e-132

   1. Initial program 33.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \]

      2. *-commutative N/A

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]

      3. lower-*.f64 33.2

         \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot 0.5} \]

      4. lift-*.f64 N/A

         \[\leadsto \sqrt{\color{blue}{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)}} \cdot \frac{1}{2} \]

      5. *-commutative N/A

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot \frac{1}{2} \]

      6. lower-*.f64 33.2

         \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + re\right) \cdot 2}} \cdot 0.5 \]

      7. lift-sqrt.f64 N/A

         \[\leadsto \sqrt{\left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      8. lift-+.f64 N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      9. +-commutative N/A

         \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im + re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      10. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{\color{blue}{im \cdot im} + re \cdot re} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      11. lift-*.f64 N/A

          \[\leadsto \sqrt{\left(\sqrt{im \cdot im + \color{blue}{re \cdot re}} + re\right) \cdot 2} \cdot \frac{1}{2} \]

      12. lower-hypot.f64 68.0

          \[\leadsto \sqrt{\left(\color{blue}{\mathsf{hypot}\left(im, re\right)} + re\right) \cdot 2} \cdot 0.5 \]

   4. Applied rewrites 68.0%

      \[\leadsto \color{blue}{\sqrt{\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2} \cdot 0.5} \]

   5. Taylor expanded in re around 0

      \[\leadsto \sqrt{\color{blue}{2 \cdot im}} \cdot \frac{1}{2} \]
   6. Step-by-step derivation

      1. lower-*.f64 31.8

         \[\leadsto \sqrt{\color{blue}{2 \cdot im}} \cdot 0.5 \]

   7. Applied rewrites 31.8%

      \[\leadsto \sqrt{\color{blue}{2 \cdot im}} \cdot 0.5 \]

   if 2.1499999999999998e-132 < re

   1. Initial program 47.3%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
   2. Add Preprocessing

   3. Taylor expanded in re around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
   4. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({\left(\sqrt{2}\right)}^{2} \cdot \sqrt{re}\right)} \]

      2. associate-*r* N/A

         \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {\left(\sqrt{2}\right)}^{2}\right) \cdot \sqrt{re}} \]

      3. unpow2 N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \sqrt{2}\right)}\right) \cdot \sqrt{re} \]

      4. rem-square-sqrt N/A

         \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{2}\right) \cdot \sqrt{re} \]

      5. metadata-eval N/A

         \[\leadsto \color{blue}{1} \cdot \sqrt{re} \]

      6. *-lft-identity N/A

         \[\leadsto \color{blue}{\sqrt{re}} \]

      7. lower-sqrt.f64 70.7

         \[\leadsto \color{blue}{\sqrt{re}} \]

   5. Applied rewrites 70.7%

      \[\leadsto \color{blue}{\sqrt{re}} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 8: 25.5% accurate, 4.3× speedup

Math

\[\begin{array}{l} \\ \sqrt{re} \end{array} \]

FPCore

(FPCore (re im) :precision binary64 (sqrt re))

C

double code(double re, double im) {
	return sqrt(re);
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = sqrt(re)
end function

Java

public static double code(double re, double im) {
	return Math.sqrt(re);
}

Python

def code(re, im):
	return math.sqrt(re)

Julia

function code(re, im)
	return sqrt(re)
end

MATLAB

function tmp = code(re, im)
	tmp = sqrt(re);
end

Wolfram

code[re_, im_] := N[Sqrt[re], $MachinePrecision]

Derivation

1. Initial program 38.1%

   \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
2. Add Preprocessing

3. Taylor expanded in re around inf

   \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
4. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({\left(\sqrt{2}\right)}^{2} \cdot \sqrt{re}\right)} \]

   2. associate-*r* N/A

      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {\left(\sqrt{2}\right)}^{2}\right) \cdot \sqrt{re}} \]

   3. unpow2 N/A

      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \sqrt{2}\right)}\right) \cdot \sqrt{re} \]

   4. rem-square-sqrt N/A

      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{2}\right) \cdot \sqrt{re} \]

   5. metadata-eval N/A

      \[\leadsto \color{blue}{1} \cdot \sqrt{re} \]

   6. *-lft-identity N/A

      \[\leadsto \color{blue}{\sqrt{re}} \]

   7. lower-sqrt.f64 26.7

      \[\leadsto \color{blue}{\sqrt{re}} \]

5. Applied rewrites 26.7%

   \[\leadsto \color{blue}{\sqrt{re}} \]
6. Add Preprocessing

Developer Target 1: 48.1% accurate, 0.6× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{re \cdot re + im \cdot im}\\ \mathbf{if}\;re < 0:\\ \;\;\;\;0.5 \cdot \left(\sqrt{2} \cdot \sqrt{\frac{im \cdot im}{t\_0 - re}}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(t\_0 + re\right)}\\ \end{array} \end{array} \]

FPCore

(FPCore (re im)
 :precision binary64
 (let* ((t_0 (sqrt (+ (* re re) (* im im)))))
   (if (< re 0.0)
     (* 0.5 (* (sqrt 2.0) (sqrt (/ (* im im) (- t_0 re)))))
     (* 0.5 (sqrt (* 2.0 (+ t_0 re)))))))

C

double code(double re, double im) {
	double t_0 = sqrt(((re * re) + (im * im)));
	double tmp;
	if (re < 0.0) {
		tmp = 0.5 * (sqrt(2.0) * sqrt(((im * im) / (t_0 - re))));
	} else {
		tmp = 0.5 * sqrt((2.0 * (t_0 + re)));
	}
	return tmp;
}

Fortran

real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sqrt(((re * re) + (im * im)))
    if (re < 0.0d0) then
        tmp = 0.5d0 * (sqrt(2.0d0) * sqrt(((im * im) / (t_0 - re))))
    else
        tmp = 0.5d0 * sqrt((2.0d0 * (t_0 + re)))
    end if
    code = tmp
end function

Java

public static double code(double re, double im) {
	double t_0 = Math.sqrt(((re * re) + (im * im)));
	double tmp;
	if (re < 0.0) {
		tmp = 0.5 * (Math.sqrt(2.0) * Math.sqrt(((im * im) / (t_0 - re))));
	} else {
		tmp = 0.5 * Math.sqrt((2.0 * (t_0 + re)));
	}
	return tmp;
}

Python

def code(re, im):
	t_0 = math.sqrt(((re * re) + (im * im)))
	tmp = 0
	if re < 0.0:
		tmp = 0.5 * (math.sqrt(2.0) * math.sqrt(((im * im) / (t_0 - re))))
	else:
		tmp = 0.5 * math.sqrt((2.0 * (t_0 + re)))
	return tmp

Julia

function code(re, im)
	t_0 = sqrt(Float64(Float64(re * re) + Float64(im * im)))
	tmp = 0.0
	if (re < 0.0)
		tmp = Float64(0.5 * Float64(sqrt(2.0) * sqrt(Float64(Float64(im * im) / Float64(t_0 - re)))));
	else
		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(t_0 + re))));
	end
	return tmp
end

MATLAB

function tmp_2 = code(re, im)
	t_0 = sqrt(((re * re) + (im * im)));
	tmp = 0.0;
	if (re < 0.0)
		tmp = 0.5 * (sqrt(2.0) * sqrt(((im * im) / (t_0 - re))));
	else
		tmp = 0.5 * sqrt((2.0 * (t_0 + re)));
	end
	tmp_2 = tmp;
end

Wolfram

code[re_, im_] := Block[{t$95$0 = N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[Less[re, 0.0], N[(0.5 * N[(N[Sqrt[2.0], $MachinePrecision] * N[Sqrt[N[(N[(im * im), $MachinePrecision] / N[(t$95$0 - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(2.0 * N[(t$95$0 + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]

Reproduce

herbie shell --seed 2024342 
(FPCore (re im)
  :name "math.sqrt on complex, real part"
  :precision binary64

  :alt
  (! :herbie-platform default (if (< re 0) (* 1/2 (* (sqrt 2) (sqrt (/ (* im im) (- (modulus re im) re))))) (* 1/2 (sqrt (* 2 (+ (modulus re im) re))))))

  (* 0.5 (sqrt (* 2.0 (+ (sqrt (+ (* re re) (* im im))) re)))))