math.sqrt on complex, imaginary part, im greater than 0 branch

Percentage Accurate: 41.3% → 90.0%
Time: 18.6s
Alternatives: 7
Speedup: 2.0×

Specification

?
\[im > 0\]
\[\begin{array}{l} \\ 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \end{array} \]
(FPCore (re im)
 :precision binary64
 (* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))
double code(double re, double im) {
	return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
}
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
public static double code(double re, double im) {
	return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) - re)));
}
def code(re, im):
	return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) - re)))
function code(re, im)
	return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) - re))))
end
function tmp = code(re, im)
	tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
end
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]
\begin{array}{l}

\\
0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 7 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 41.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \end{array} \]
(FPCore (re im)
 :precision binary64
 (* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))
double code(double re, double im) {
	return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
}
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
public static double code(double re, double im) {
	return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) - re)));
}
def code(re, im):
	return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) - re)))
function code(re, im)
	return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) - re))))
end
function tmp = code(re, im)
	tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
end
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]
\begin{array}{l}

\\
0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}
\end{array}

Alternative 1: 90.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sqrt{re \cdot re + im \cdot im} - re \leq 0:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (if (<= (- (sqrt (+ (* re re) (* im im))) re) 0.0)
   (* 0.5 (* im (pow re -0.5)))
   (* 0.5 (sqrt (* 2.0 (- (hypot re im) re))))))
double code(double re, double im) {
	double tmp;
	if ((sqrt(((re * re) + (im * im))) - re) <= 0.0) {
		tmp = 0.5 * (im * pow(re, -0.5));
	} else {
		tmp = 0.5 * sqrt((2.0 * (hypot(re, im) - re)));
	}
	return tmp;
}
public static double code(double re, double im) {
	double tmp;
	if ((Math.sqrt(((re * re) + (im * im))) - re) <= 0.0) {
		tmp = 0.5 * (im * Math.pow(re, -0.5));
	} else {
		tmp = 0.5 * Math.sqrt((2.0 * (Math.hypot(re, im) - re)));
	}
	return tmp;
}
def code(re, im):
	tmp = 0
	if (math.sqrt(((re * re) + (im * im))) - re) <= 0.0:
		tmp = 0.5 * (im * math.pow(re, -0.5))
	else:
		tmp = 0.5 * math.sqrt((2.0 * (math.hypot(re, im) - re)))
	return tmp
function code(re, im)
	tmp = 0.0
	if (Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) - re) <= 0.0)
		tmp = Float64(0.5 * Float64(im * (re ^ -0.5)));
	else
		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(hypot(re, im) - re))));
	end
	return tmp
end
function tmp_2 = code(re, im)
	tmp = 0.0;
	if ((sqrt(((re * re) + (im * im))) - re) <= 0.0)
		tmp = 0.5 * (im * (re ^ -0.5));
	else
		tmp = 0.5 * sqrt((2.0 * (hypot(re, im) - re)));
	end
	tmp_2 = tmp;
end
code[re_, im_] := If[LessEqual[N[(N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - re), $MachinePrecision], 0.0], N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision] - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\sqrt{re \cdot re + im \cdot im} - re \leq 0:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sqrt.f64 (+.f64 (*.f64 re re) (*.f64 im im))) re) < 0.0

    1. Initial program 6.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 29.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/229.9%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv30.0%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down32.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/232.8%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow32.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow32.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval32.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr32.8%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative32.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow232.8%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square97.2%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified97.2%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Taylor expanded in re around 0 97.2%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{\frac{1}{re}} \cdot \left|im\right|\right)} \]
    9. Step-by-step derivation
      1. rem-square-sqrt96.6%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|\right) \]
      2. fabs-sqr96.6%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{\left(\sqrt{im} \cdot \sqrt{im}\right)}\right) \]
      3. rem-square-sqrt97.2%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{im}\right) \]
      4. unpow1/297.2%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{\left(\frac{1}{re}\right)}^{0.5}} \cdot im\right) \]
      5. rem-exp-log91.2%

        \[\leadsto 0.5 \cdot \left({\left(\frac{1}{\color{blue}{e^{\log re}}}\right)}^{0.5} \cdot im\right) \]
      6. exp-neg91.2%

        \[\leadsto 0.5 \cdot \left({\color{blue}{\left(e^{-\log re}\right)}}^{0.5} \cdot im\right) \]
      7. exp-prod91.2%

        \[\leadsto 0.5 \cdot \left(\color{blue}{e^{\left(-\log re\right) \cdot 0.5}} \cdot im\right) \]
      8. distribute-lft-neg-out91.2%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{-\log re \cdot 0.5}} \cdot im\right) \]
      9. distribute-rgt-neg-in91.2%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{\log re \cdot \left(-0.5\right)}} \cdot im\right) \]
      10. metadata-eval91.2%

        \[\leadsto 0.5 \cdot \left(e^{\log re \cdot \color{blue}{-0.5}} \cdot im\right) \]
      11. exp-to-pow97.2%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{re}^{-0.5}} \cdot im\right) \]
    10. Simplified97.2%

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

    if 0.0 < (-.f64 (sqrt.f64 (+.f64 (*.f64 re re) (*.f64 im im))) re)

    1. Initial program 48.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Step-by-step derivation
      1. sub-neg48.5%

        \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + \left(-re\right)\right)}} \]
      2. sqr-neg48.5%

        \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + \color{blue}{\left(-im\right) \cdot \left(-im\right)}} + \left(-re\right)\right)} \]
      3. sub-neg48.5%

        \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(\sqrt{re \cdot re + \left(-im\right) \cdot \left(-im\right)} - re\right)}} \]
      4. sqr-neg48.5%

        \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + \color{blue}{im \cdot im}} - re\right)} \]
      5. hypot-define90.6%

        \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\color{blue}{\mathsf{hypot}\left(re, im\right)} - re\right)} \]
    3. Simplified90.6%

      \[\leadsto \color{blue}{0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification91.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sqrt{re \cdot re + im \cdot im} - re \leq 0:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 74.4% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \frac{im}{\sqrt{re}}\\ t_1 := 0.5 \cdot \sqrt{re \cdot -4}\\ t_2 := 0.5 \cdot \sqrt{im \cdot 2}\\ t_3 := 0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{if}\;re \leq -2.1 \cdot 10^{+77}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq -6.5:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;re \leq -4.5 \cdot 10^{-61}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq -4.2 \cdot 10^{-93}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq -1.28 \cdot 10^{-135}:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq 9.5 \cdot 10^{-54}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\ \mathbf{elif}\;re \leq 1.6 \cdot 10^{+25}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq 5.5 \cdot 10^{+72}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\ \;\;\;\;t\_2\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (* 0.5 (/ im (sqrt re))))
        (t_1 (* 0.5 (sqrt (* re -4.0))))
        (t_2 (* 0.5 (sqrt (* im 2.0))))
        (t_3 (* 0.5 (sqrt (* 2.0 (- im re))))))
   (if (<= re -2.1e+77)
     t_1
     (if (<= re -6.5)
       t_3
       (if (<= re -4.5e-61)
         t_1
         (if (<= re -4.2e-93)
           t_2
           (if (<= re -5.5e-99)
             t_1
             (if (<= re -1.28e-135)
               t_3
               (if (<= re -1.32e-136)
                 t_1
                 (if (<= re 9.5e-54)
                   (* 0.5 (sqrt (+ (* im 2.0) (* re (- (/ re im) 2.0)))))
                   (if (<= re 1.6e+25)
                     t_0
                     (if (<= re 1.95e+58)
                       t_2
                       (if (<= re 5.5e+72)
                         t_0
                         (if (<= re 2.3e+125)
                           t_2
                           (* 0.5 (* im (pow re -0.5)))))))))))))))))
double code(double re, double im) {
	double t_0 = 0.5 * (im / sqrt(re));
	double t_1 = 0.5 * sqrt((re * -4.0));
	double t_2 = 0.5 * sqrt((im * 2.0));
	double t_3 = 0.5 * sqrt((2.0 * (im - re)));
	double tmp;
	if (re <= -2.1e+77) {
		tmp = t_1;
	} else if (re <= -6.5) {
		tmp = t_3;
	} else if (re <= -4.5e-61) {
		tmp = t_1;
	} else if (re <= -4.2e-93) {
		tmp = t_2;
	} else if (re <= -5.5e-99) {
		tmp = t_1;
	} else if (re <= -1.28e-135) {
		tmp = t_3;
	} else if (re <= -1.32e-136) {
		tmp = t_1;
	} else if (re <= 9.5e-54) {
		tmp = 0.5 * sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	} else if (re <= 1.6e+25) {
		tmp = t_0;
	} else if (re <= 1.95e+58) {
		tmp = t_2;
	} else if (re <= 5.5e+72) {
		tmp = t_0;
	} else if (re <= 2.3e+125) {
		tmp = t_2;
	} else {
		tmp = 0.5 * (im * pow(re, -0.5));
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: t_3
    real(8) :: tmp
    t_0 = 0.5d0 * (im / sqrt(re))
    t_1 = 0.5d0 * sqrt((re * (-4.0d0)))
    t_2 = 0.5d0 * sqrt((im * 2.0d0))
    t_3 = 0.5d0 * sqrt((2.0d0 * (im - re)))
    if (re <= (-2.1d+77)) then
        tmp = t_1
    else if (re <= (-6.5d0)) then
        tmp = t_3
    else if (re <= (-4.5d-61)) then
        tmp = t_1
    else if (re <= (-4.2d-93)) then
        tmp = t_2
    else if (re <= (-5.5d-99)) then
        tmp = t_1
    else if (re <= (-1.28d-135)) then
        tmp = t_3
    else if (re <= (-1.32d-136)) then
        tmp = t_1
    else if (re <= 9.5d-54) then
        tmp = 0.5d0 * sqrt(((im * 2.0d0) + (re * ((re / im) - 2.0d0))))
    else if (re <= 1.6d+25) then
        tmp = t_0
    else if (re <= 1.95d+58) then
        tmp = t_2
    else if (re <= 5.5d+72) then
        tmp = t_0
    else if (re <= 2.3d+125) then
        tmp = t_2
    else
        tmp = 0.5d0 * (im * (re ** (-0.5d0)))
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = 0.5 * (im / Math.sqrt(re));
	double t_1 = 0.5 * Math.sqrt((re * -4.0));
	double t_2 = 0.5 * Math.sqrt((im * 2.0));
	double t_3 = 0.5 * Math.sqrt((2.0 * (im - re)));
	double tmp;
	if (re <= -2.1e+77) {
		tmp = t_1;
	} else if (re <= -6.5) {
		tmp = t_3;
	} else if (re <= -4.5e-61) {
		tmp = t_1;
	} else if (re <= -4.2e-93) {
		tmp = t_2;
	} else if (re <= -5.5e-99) {
		tmp = t_1;
	} else if (re <= -1.28e-135) {
		tmp = t_3;
	} else if (re <= -1.32e-136) {
		tmp = t_1;
	} else if (re <= 9.5e-54) {
		tmp = 0.5 * Math.sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	} else if (re <= 1.6e+25) {
		tmp = t_0;
	} else if (re <= 1.95e+58) {
		tmp = t_2;
	} else if (re <= 5.5e+72) {
		tmp = t_0;
	} else if (re <= 2.3e+125) {
		tmp = t_2;
	} else {
		tmp = 0.5 * (im * Math.pow(re, -0.5));
	}
	return tmp;
}
def code(re, im):
	t_0 = 0.5 * (im / math.sqrt(re))
	t_1 = 0.5 * math.sqrt((re * -4.0))
	t_2 = 0.5 * math.sqrt((im * 2.0))
	t_3 = 0.5 * math.sqrt((2.0 * (im - re)))
	tmp = 0
	if re <= -2.1e+77:
		tmp = t_1
	elif re <= -6.5:
		tmp = t_3
	elif re <= -4.5e-61:
		tmp = t_1
	elif re <= -4.2e-93:
		tmp = t_2
	elif re <= -5.5e-99:
		tmp = t_1
	elif re <= -1.28e-135:
		tmp = t_3
	elif re <= -1.32e-136:
		tmp = t_1
	elif re <= 9.5e-54:
		tmp = 0.5 * math.sqrt(((im * 2.0) + (re * ((re / im) - 2.0))))
	elif re <= 1.6e+25:
		tmp = t_0
	elif re <= 1.95e+58:
		tmp = t_2
	elif re <= 5.5e+72:
		tmp = t_0
	elif re <= 2.3e+125:
		tmp = t_2
	else:
		tmp = 0.5 * (im * math.pow(re, -0.5))
	return tmp
function code(re, im)
	t_0 = Float64(0.5 * Float64(im / sqrt(re)))
	t_1 = Float64(0.5 * sqrt(Float64(re * -4.0)))
	t_2 = Float64(0.5 * sqrt(Float64(im * 2.0)))
	t_3 = Float64(0.5 * sqrt(Float64(2.0 * Float64(im - re))))
	tmp = 0.0
	if (re <= -2.1e+77)
		tmp = t_1;
	elseif (re <= -6.5)
		tmp = t_3;
	elseif (re <= -4.5e-61)
		tmp = t_1;
	elseif (re <= -4.2e-93)
		tmp = t_2;
	elseif (re <= -5.5e-99)
		tmp = t_1;
	elseif (re <= -1.28e-135)
		tmp = t_3;
	elseif (re <= -1.32e-136)
		tmp = t_1;
	elseif (re <= 9.5e-54)
		tmp = Float64(0.5 * sqrt(Float64(Float64(im * 2.0) + Float64(re * Float64(Float64(re / im) - 2.0)))));
	elseif (re <= 1.6e+25)
		tmp = t_0;
	elseif (re <= 1.95e+58)
		tmp = t_2;
	elseif (re <= 5.5e+72)
		tmp = t_0;
	elseif (re <= 2.3e+125)
		tmp = t_2;
	else
		tmp = Float64(0.5 * Float64(im * (re ^ -0.5)));
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = 0.5 * (im / sqrt(re));
	t_1 = 0.5 * sqrt((re * -4.0));
	t_2 = 0.5 * sqrt((im * 2.0));
	t_3 = 0.5 * sqrt((2.0 * (im - re)));
	tmp = 0.0;
	if (re <= -2.1e+77)
		tmp = t_1;
	elseif (re <= -6.5)
		tmp = t_3;
	elseif (re <= -4.5e-61)
		tmp = t_1;
	elseif (re <= -4.2e-93)
		tmp = t_2;
	elseif (re <= -5.5e-99)
		tmp = t_1;
	elseif (re <= -1.28e-135)
		tmp = t_3;
	elseif (re <= -1.32e-136)
		tmp = t_1;
	elseif (re <= 9.5e-54)
		tmp = 0.5 * sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	elseif (re <= 1.6e+25)
		tmp = t_0;
	elseif (re <= 1.95e+58)
		tmp = t_2;
	elseif (re <= 5.5e+72)
		tmp = t_0;
	elseif (re <= 2.3e+125)
		tmp = t_2;
	else
		tmp = 0.5 * (im * (re ^ -0.5));
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(0.5 * N[Sqrt[N[(2.0 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[re, -2.1e+77], t$95$1, If[LessEqual[re, -6.5], t$95$3, If[LessEqual[re, -4.5e-61], t$95$1, If[LessEqual[re, -4.2e-93], t$95$2, If[LessEqual[re, -5.5e-99], t$95$1, If[LessEqual[re, -1.28e-135], t$95$3, If[LessEqual[re, -1.32e-136], t$95$1, If[LessEqual[re, 9.5e-54], N[(0.5 * N[Sqrt[N[(N[(im * 2.0), $MachinePrecision] + N[(re * N[(N[(re / im), $MachinePrecision] - 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 1.6e+25], t$95$0, If[LessEqual[re, 1.95e+58], t$95$2, If[LessEqual[re, 5.5e+72], t$95$0, If[LessEqual[re, 2.3e+125], t$95$2, N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \frac{im}{\sqrt{re}}\\
t_1 := 0.5 \cdot \sqrt{re \cdot -4}\\
t_2 := 0.5 \cdot \sqrt{im \cdot 2}\\
t_3 := 0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\
\mathbf{if}\;re \leq -2.1 \cdot 10^{+77}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq -6.5:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;re \leq -4.5 \cdot 10^{-61}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq -4.2 \cdot 10^{-93}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq -1.28 \cdot 10^{-135}:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq 9.5 \cdot 10^{-54}:\\
\;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\

\mathbf{elif}\;re \leq 1.6 \cdot 10^{+25}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq 5.5 \cdot 10^{+72}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\
\;\;\;\;t\_2\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if re < -2.0999999999999999e77 or -6.5 < re < -4.5e-61 or -4.2000000000000002e-93 < re < -5.49999999999999991e-99 or -1.27999999999999997e-135 < re < -1.3200000000000001e-136

    1. Initial program 42.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative83.1%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]

    if -2.0999999999999999e77 < re < -6.5 or -5.49999999999999991e-99 < re < -1.27999999999999997e-135

    1. Initial program 61.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 74.5%

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

    if -4.5e-61 < re < -4.2000000000000002e-93 or 1.6e25 < re < 1.95000000000000005e58 or 5.5e72 < re < 2.30000000000000013e125

    1. Initial program 53.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 86.3%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
    4. Step-by-step derivation
      1. *-commutative86.3%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
    5. Simplified86.3%

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

    if -1.3200000000000001e-136 < re < 9.4999999999999994e-54

    1. Initial program 55.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 82.4%

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

    if 9.4999999999999994e-54 < re < 1.6e25 or 1.95000000000000005e58 < re < 5.5e72

    1. Initial program 31.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 27.4%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/227.4%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv27.4%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down31.9%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/231.9%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow31.9%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow31.9%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval31.9%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr31.9%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative31.9%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow231.9%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square73.3%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified73.3%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Step-by-step derivation
      1. *-commutative73.3%

        \[\leadsto 0.5 \cdot \color{blue}{\left(\left|im\right| \cdot {re}^{-0.5}\right)} \]
      2. metadata-eval73.3%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot {re}^{\color{blue}{\left(-0.5\right)}}\right) \]
      3. pow-flip73.3%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \color{blue}{\frac{1}{{re}^{0.5}}}\right) \]
      4. pow1/273.3%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \frac{1}{\color{blue}{\sqrt{re}}}\right) \]
      5. div-inv73.4%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\left|im\right|}{\sqrt{re}}} \]
      6. add-sqr-sqrt72.9%

        \[\leadsto 0.5 \cdot \frac{\left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|}{\sqrt{re}} \]
      7. fabs-sqr72.9%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{\sqrt{im} \cdot \sqrt{im}}}{\sqrt{re}} \]
      8. add-sqr-sqrt73.4%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    9. Applied egg-rr73.4%

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

    if 2.30000000000000013e125 < re

    1. Initial program 3.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 54.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/254.9%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv54.9%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down68.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/268.8%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr68.8%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative68.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow268.8%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square87.4%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Taylor expanded in re around 0 87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{\frac{1}{re}} \cdot \left|im\right|\right)} \]
    9. Step-by-step derivation
      1. rem-square-sqrt87.0%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|\right) \]
      2. fabs-sqr87.0%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{\left(\sqrt{im} \cdot \sqrt{im}\right)}\right) \]
      3. rem-square-sqrt87.4%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{im}\right) \]
      4. unpow1/287.4%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{\left(\frac{1}{re}\right)}^{0.5}} \cdot im\right) \]
      5. rem-exp-log82.0%

        \[\leadsto 0.5 \cdot \left({\left(\frac{1}{\color{blue}{e^{\log re}}}\right)}^{0.5} \cdot im\right) \]
      6. exp-neg82.0%

        \[\leadsto 0.5 \cdot \left({\color{blue}{\left(e^{-\log re}\right)}}^{0.5} \cdot im\right) \]
      7. exp-prod82.0%

        \[\leadsto 0.5 \cdot \left(\color{blue}{e^{\left(-\log re\right) \cdot 0.5}} \cdot im\right) \]
      8. distribute-lft-neg-out82.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{-\log re \cdot 0.5}} \cdot im\right) \]
      9. distribute-rgt-neg-in82.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{\log re \cdot \left(-0.5\right)}} \cdot im\right) \]
      10. metadata-eval82.0%

        \[\leadsto 0.5 \cdot \left(e^{\log re \cdot \color{blue}{-0.5}} \cdot im\right) \]
      11. exp-to-pow87.4%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{re}^{-0.5}} \cdot im\right) \]
    10. Simplified87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot im\right)} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification82.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -2.1 \cdot 10^{+77}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -6.5:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq -4.5 \cdot 10^{-61}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -4.2 \cdot 10^{-93}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -1.28 \cdot 10^{-135}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq 9.5 \cdot 10^{-54}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\ \mathbf{elif}\;re \leq 1.6 \cdot 10^{+25}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq 5.5 \cdot 10^{+72}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 74.3% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\ t_1 := 0.5 \cdot \sqrt{im \cdot 2}\\ t_2 := 0.5 \cdot \frac{im}{\sqrt{re}}\\ t_3 := 0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{if}\;re \leq -1.15 \cdot 10^{+77}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq -150000:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;re \leq -5.8 \cdot 10^{-61}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq -1.35 \cdot 10^{-92}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq -8.5 \cdot 10^{-133}:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 1.2 \cdot 10^{-52}:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;re \leq 4 \cdot 10^{+24}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq 1.02 \cdot 10^{+58}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq 2.9 \cdot 10^{+72}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (* 0.5 (sqrt (* re -4.0))))
        (t_1 (* 0.5 (sqrt (* im 2.0))))
        (t_2 (* 0.5 (/ im (sqrt re))))
        (t_3 (* 0.5 (sqrt (* 2.0 (- im re))))))
   (if (<= re -1.15e+77)
     t_0
     (if (<= re -150000.0)
       t_3
       (if (<= re -5.8e-61)
         t_0
         (if (<= re -1.35e-92)
           t_1
           (if (<= re -5.5e-99)
             t_0
             (if (<= re -8.5e-133)
               t_3
               (if (<= re -1.32e-136)
                 t_0
                 (if (<= re 1.2e-52)
                   t_3
                   (if (<= re 4e+24)
                     t_2
                     (if (<= re 1.02e+58)
                       t_1
                       (if (<= re 2.9e+72)
                         t_2
                         (if (<= re 2.3e+125)
                           t_1
                           (* 0.5 (* im (pow re -0.5)))))))))))))))))
double code(double re, double im) {
	double t_0 = 0.5 * sqrt((re * -4.0));
	double t_1 = 0.5 * sqrt((im * 2.0));
	double t_2 = 0.5 * (im / sqrt(re));
	double t_3 = 0.5 * sqrt((2.0 * (im - re)));
	double tmp;
	if (re <= -1.15e+77) {
		tmp = t_0;
	} else if (re <= -150000.0) {
		tmp = t_3;
	} else if (re <= -5.8e-61) {
		tmp = t_0;
	} else if (re <= -1.35e-92) {
		tmp = t_1;
	} else if (re <= -5.5e-99) {
		tmp = t_0;
	} else if (re <= -8.5e-133) {
		tmp = t_3;
	} else if (re <= -1.32e-136) {
		tmp = t_0;
	} else if (re <= 1.2e-52) {
		tmp = t_3;
	} else if (re <= 4e+24) {
		tmp = t_2;
	} else if (re <= 1.02e+58) {
		tmp = t_1;
	} else if (re <= 2.9e+72) {
		tmp = t_2;
	} else if (re <= 2.3e+125) {
		tmp = t_1;
	} else {
		tmp = 0.5 * (im * pow(re, -0.5));
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: t_3
    real(8) :: tmp
    t_0 = 0.5d0 * sqrt((re * (-4.0d0)))
    t_1 = 0.5d0 * sqrt((im * 2.0d0))
    t_2 = 0.5d0 * (im / sqrt(re))
    t_3 = 0.5d0 * sqrt((2.0d0 * (im - re)))
    if (re <= (-1.15d+77)) then
        tmp = t_0
    else if (re <= (-150000.0d0)) then
        tmp = t_3
    else if (re <= (-5.8d-61)) then
        tmp = t_0
    else if (re <= (-1.35d-92)) then
        tmp = t_1
    else if (re <= (-5.5d-99)) then
        tmp = t_0
    else if (re <= (-8.5d-133)) then
        tmp = t_3
    else if (re <= (-1.32d-136)) then
        tmp = t_0
    else if (re <= 1.2d-52) then
        tmp = t_3
    else if (re <= 4d+24) then
        tmp = t_2
    else if (re <= 1.02d+58) then
        tmp = t_1
    else if (re <= 2.9d+72) then
        tmp = t_2
    else if (re <= 2.3d+125) then
        tmp = t_1
    else
        tmp = 0.5d0 * (im * (re ** (-0.5d0)))
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = 0.5 * Math.sqrt((re * -4.0));
	double t_1 = 0.5 * Math.sqrt((im * 2.0));
	double t_2 = 0.5 * (im / Math.sqrt(re));
	double t_3 = 0.5 * Math.sqrt((2.0 * (im - re)));
	double tmp;
	if (re <= -1.15e+77) {
		tmp = t_0;
	} else if (re <= -150000.0) {
		tmp = t_3;
	} else if (re <= -5.8e-61) {
		tmp = t_0;
	} else if (re <= -1.35e-92) {
		tmp = t_1;
	} else if (re <= -5.5e-99) {
		tmp = t_0;
	} else if (re <= -8.5e-133) {
		tmp = t_3;
	} else if (re <= -1.32e-136) {
		tmp = t_0;
	} else if (re <= 1.2e-52) {
		tmp = t_3;
	} else if (re <= 4e+24) {
		tmp = t_2;
	} else if (re <= 1.02e+58) {
		tmp = t_1;
	} else if (re <= 2.9e+72) {
		tmp = t_2;
	} else if (re <= 2.3e+125) {
		tmp = t_1;
	} else {
		tmp = 0.5 * (im * Math.pow(re, -0.5));
	}
	return tmp;
}
def code(re, im):
	t_0 = 0.5 * math.sqrt((re * -4.0))
	t_1 = 0.5 * math.sqrt((im * 2.0))
	t_2 = 0.5 * (im / math.sqrt(re))
	t_3 = 0.5 * math.sqrt((2.0 * (im - re)))
	tmp = 0
	if re <= -1.15e+77:
		tmp = t_0
	elif re <= -150000.0:
		tmp = t_3
	elif re <= -5.8e-61:
		tmp = t_0
	elif re <= -1.35e-92:
		tmp = t_1
	elif re <= -5.5e-99:
		tmp = t_0
	elif re <= -8.5e-133:
		tmp = t_3
	elif re <= -1.32e-136:
		tmp = t_0
	elif re <= 1.2e-52:
		tmp = t_3
	elif re <= 4e+24:
		tmp = t_2
	elif re <= 1.02e+58:
		tmp = t_1
	elif re <= 2.9e+72:
		tmp = t_2
	elif re <= 2.3e+125:
		tmp = t_1
	else:
		tmp = 0.5 * (im * math.pow(re, -0.5))
	return tmp
function code(re, im)
	t_0 = Float64(0.5 * sqrt(Float64(re * -4.0)))
	t_1 = Float64(0.5 * sqrt(Float64(im * 2.0)))
	t_2 = Float64(0.5 * Float64(im / sqrt(re)))
	t_3 = Float64(0.5 * sqrt(Float64(2.0 * Float64(im - re))))
	tmp = 0.0
	if (re <= -1.15e+77)
		tmp = t_0;
	elseif (re <= -150000.0)
		tmp = t_3;
	elseif (re <= -5.8e-61)
		tmp = t_0;
	elseif (re <= -1.35e-92)
		tmp = t_1;
	elseif (re <= -5.5e-99)
		tmp = t_0;
	elseif (re <= -8.5e-133)
		tmp = t_3;
	elseif (re <= -1.32e-136)
		tmp = t_0;
	elseif (re <= 1.2e-52)
		tmp = t_3;
	elseif (re <= 4e+24)
		tmp = t_2;
	elseif (re <= 1.02e+58)
		tmp = t_1;
	elseif (re <= 2.9e+72)
		tmp = t_2;
	elseif (re <= 2.3e+125)
		tmp = t_1;
	else
		tmp = Float64(0.5 * Float64(im * (re ^ -0.5)));
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = 0.5 * sqrt((re * -4.0));
	t_1 = 0.5 * sqrt((im * 2.0));
	t_2 = 0.5 * (im / sqrt(re));
	t_3 = 0.5 * sqrt((2.0 * (im - re)));
	tmp = 0.0;
	if (re <= -1.15e+77)
		tmp = t_0;
	elseif (re <= -150000.0)
		tmp = t_3;
	elseif (re <= -5.8e-61)
		tmp = t_0;
	elseif (re <= -1.35e-92)
		tmp = t_1;
	elseif (re <= -5.5e-99)
		tmp = t_0;
	elseif (re <= -8.5e-133)
		tmp = t_3;
	elseif (re <= -1.32e-136)
		tmp = t_0;
	elseif (re <= 1.2e-52)
		tmp = t_3;
	elseif (re <= 4e+24)
		tmp = t_2;
	elseif (re <= 1.02e+58)
		tmp = t_1;
	elseif (re <= 2.9e+72)
		tmp = t_2;
	elseif (re <= 2.3e+125)
		tmp = t_1;
	else
		tmp = 0.5 * (im * (re ^ -0.5));
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(0.5 * N[Sqrt[N[(2.0 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[re, -1.15e+77], t$95$0, If[LessEqual[re, -150000.0], t$95$3, If[LessEqual[re, -5.8e-61], t$95$0, If[LessEqual[re, -1.35e-92], t$95$1, If[LessEqual[re, -5.5e-99], t$95$0, If[LessEqual[re, -8.5e-133], t$95$3, If[LessEqual[re, -1.32e-136], t$95$0, If[LessEqual[re, 1.2e-52], t$95$3, If[LessEqual[re, 4e+24], t$95$2, If[LessEqual[re, 1.02e+58], t$95$1, If[LessEqual[re, 2.9e+72], t$95$2, If[LessEqual[re, 2.3e+125], t$95$1, N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\
t_1 := 0.5 \cdot \sqrt{im \cdot 2}\\
t_2 := 0.5 \cdot \frac{im}{\sqrt{re}}\\
t_3 := 0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\
\mathbf{if}\;re \leq -1.15 \cdot 10^{+77}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq -150000:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;re \leq -5.8 \cdot 10^{-61}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq -1.35 \cdot 10^{-92}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq -8.5 \cdot 10^{-133}:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 1.2 \cdot 10^{-52}:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;re \leq 4 \cdot 10^{+24}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq 1.02 \cdot 10^{+58}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq 2.9 \cdot 10^{+72}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 5 regimes
  2. if re < -1.14999999999999997e77 or -1.5e5 < re < -5.7999999999999999e-61 or -1.34999999999999998e-92 < re < -5.49999999999999991e-99 or -8.49999999999999957e-133 < re < -1.3200000000000001e-136

    1. Initial program 42.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative83.1%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]

    if -1.14999999999999997e77 < re < -1.5e5 or -5.49999999999999991e-99 < re < -8.49999999999999957e-133 or -1.3200000000000001e-136 < re < 1.2000000000000001e-52

    1. Initial program 57.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 79.8%

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

    if -5.7999999999999999e-61 < re < -1.34999999999999998e-92 or 3.9999999999999999e24 < re < 1.02000000000000005e58 or 2.90000000000000017e72 < re < 2.30000000000000013e125

    1. Initial program 53.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 86.3%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
    4. Step-by-step derivation
      1. *-commutative86.3%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
    5. Simplified86.3%

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

    if 1.2000000000000001e-52 < re < 3.9999999999999999e24 or 1.02000000000000005e58 < re < 2.90000000000000017e72

    1. Initial program 27.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 28.4%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/228.4%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv28.4%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down33.1%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/233.1%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr33.1%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative33.1%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow233.1%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square76.5%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified76.5%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Step-by-step derivation
      1. *-commutative76.5%

        \[\leadsto 0.5 \cdot \color{blue}{\left(\left|im\right| \cdot {re}^{-0.5}\right)} \]
      2. metadata-eval76.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot {re}^{\color{blue}{\left(-0.5\right)}}\right) \]
      3. pow-flip76.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \color{blue}{\frac{1}{{re}^{0.5}}}\right) \]
      4. pow1/276.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \frac{1}{\color{blue}{\sqrt{re}}}\right) \]
      5. div-inv76.6%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\left|im\right|}{\sqrt{re}}} \]
      6. add-sqr-sqrt76.1%

        \[\leadsto 0.5 \cdot \frac{\left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|}{\sqrt{re}} \]
      7. fabs-sqr76.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{\sqrt{im} \cdot \sqrt{im}}}{\sqrt{re}} \]
      8. add-sqr-sqrt76.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    9. Applied egg-rr76.6%

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

    if 2.30000000000000013e125 < re

    1. Initial program 3.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 54.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/254.9%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv54.9%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down68.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/268.8%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval68.8%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr68.8%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative68.8%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow268.8%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square87.4%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Taylor expanded in re around 0 87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{\frac{1}{re}} \cdot \left|im\right|\right)} \]
    9. Step-by-step derivation
      1. rem-square-sqrt87.0%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|\right) \]
      2. fabs-sqr87.0%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{\left(\sqrt{im} \cdot \sqrt{im}\right)}\right) \]
      3. rem-square-sqrt87.4%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{im}\right) \]
      4. unpow1/287.4%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{\left(\frac{1}{re}\right)}^{0.5}} \cdot im\right) \]
      5. rem-exp-log82.0%

        \[\leadsto 0.5 \cdot \left({\left(\frac{1}{\color{blue}{e^{\log re}}}\right)}^{0.5} \cdot im\right) \]
      6. exp-neg82.0%

        \[\leadsto 0.5 \cdot \left({\color{blue}{\left(e^{-\log re}\right)}}^{0.5} \cdot im\right) \]
      7. exp-prod82.0%

        \[\leadsto 0.5 \cdot \left(\color{blue}{e^{\left(-\log re\right) \cdot 0.5}} \cdot im\right) \]
      8. distribute-lft-neg-out82.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{-\log re \cdot 0.5}} \cdot im\right) \]
      9. distribute-rgt-neg-in82.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{\log re \cdot \left(-0.5\right)}} \cdot im\right) \]
      10. metadata-eval82.0%

        \[\leadsto 0.5 \cdot \left(e^{\log re \cdot \color{blue}{-0.5}} \cdot im\right) \]
      11. exp-to-pow87.4%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{re}^{-0.5}} \cdot im\right) \]
    10. Simplified87.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot im\right)} \]
  3. Recombined 5 regimes into one program.
  4. Final simplification82.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -1.15 \cdot 10^{+77}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -150000:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq -5.8 \cdot 10^{-61}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -1.35 \cdot 10^{-92}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq -5.5 \cdot 10^{-99}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -8.5 \cdot 10^{-133}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq -1.32 \cdot 10^{-136}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq 1.2 \cdot 10^{-52}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 4 \cdot 10^{+24}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 1.02 \cdot 10^{+58}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq 2.9 \cdot 10^{+72}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 2.3 \cdot 10^{+125}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 74.7% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\ t_1 := 0.5 \cdot \frac{im}{\sqrt{re}}\\ t_2 := 0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{if}\;re \leq -2.4 \cdot 10^{+77}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq -0.00022:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq -1.75 \cdot 10^{-43}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 2.9 \cdot 10^{-52}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq 1.45 \cdot 10^{+21}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;re \leq 5.6 \cdot 10^{+72}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq 2.15 \cdot 10^{+99}:\\ \;\;\;\;t\_2\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (* 0.5 (sqrt (* re -4.0))))
        (t_1 (* 0.5 (/ im (sqrt re))))
        (t_2 (* 0.5 (sqrt (* im 2.0)))))
   (if (<= re -2.4e+77)
     t_0
     (if (<= re -0.00022)
       t_2
       (if (<= re -1.75e-43)
         t_0
         (if (<= re 2.9e-52)
           t_2
           (if (<= re 1.45e+21)
             t_1
             (if (<= re 1.95e+58)
               t_2
               (if (<= re 5.6e+72)
                 t_1
                 (if (<= re 2.15e+99)
                   t_2
                   (* 0.5 (* im (pow re -0.5)))))))))))))
double code(double re, double im) {
	double t_0 = 0.5 * sqrt((re * -4.0));
	double t_1 = 0.5 * (im / sqrt(re));
	double t_2 = 0.5 * sqrt((im * 2.0));
	double tmp;
	if (re <= -2.4e+77) {
		tmp = t_0;
	} else if (re <= -0.00022) {
		tmp = t_2;
	} else if (re <= -1.75e-43) {
		tmp = t_0;
	} else if (re <= 2.9e-52) {
		tmp = t_2;
	} else if (re <= 1.45e+21) {
		tmp = t_1;
	} else if (re <= 1.95e+58) {
		tmp = t_2;
	} else if (re <= 5.6e+72) {
		tmp = t_1;
	} else if (re <= 2.15e+99) {
		tmp = t_2;
	} else {
		tmp = 0.5 * (im * pow(re, -0.5));
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: tmp
    t_0 = 0.5d0 * sqrt((re * (-4.0d0)))
    t_1 = 0.5d0 * (im / sqrt(re))
    t_2 = 0.5d0 * sqrt((im * 2.0d0))
    if (re <= (-2.4d+77)) then
        tmp = t_0
    else if (re <= (-0.00022d0)) then
        tmp = t_2
    else if (re <= (-1.75d-43)) then
        tmp = t_0
    else if (re <= 2.9d-52) then
        tmp = t_2
    else if (re <= 1.45d+21) then
        tmp = t_1
    else if (re <= 1.95d+58) then
        tmp = t_2
    else if (re <= 5.6d+72) then
        tmp = t_1
    else if (re <= 2.15d+99) then
        tmp = t_2
    else
        tmp = 0.5d0 * (im * (re ** (-0.5d0)))
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = 0.5 * Math.sqrt((re * -4.0));
	double t_1 = 0.5 * (im / Math.sqrt(re));
	double t_2 = 0.5 * Math.sqrt((im * 2.0));
	double tmp;
	if (re <= -2.4e+77) {
		tmp = t_0;
	} else if (re <= -0.00022) {
		tmp = t_2;
	} else if (re <= -1.75e-43) {
		tmp = t_0;
	} else if (re <= 2.9e-52) {
		tmp = t_2;
	} else if (re <= 1.45e+21) {
		tmp = t_1;
	} else if (re <= 1.95e+58) {
		tmp = t_2;
	} else if (re <= 5.6e+72) {
		tmp = t_1;
	} else if (re <= 2.15e+99) {
		tmp = t_2;
	} else {
		tmp = 0.5 * (im * Math.pow(re, -0.5));
	}
	return tmp;
}
def code(re, im):
	t_0 = 0.5 * math.sqrt((re * -4.0))
	t_1 = 0.5 * (im / math.sqrt(re))
	t_2 = 0.5 * math.sqrt((im * 2.0))
	tmp = 0
	if re <= -2.4e+77:
		tmp = t_0
	elif re <= -0.00022:
		tmp = t_2
	elif re <= -1.75e-43:
		tmp = t_0
	elif re <= 2.9e-52:
		tmp = t_2
	elif re <= 1.45e+21:
		tmp = t_1
	elif re <= 1.95e+58:
		tmp = t_2
	elif re <= 5.6e+72:
		tmp = t_1
	elif re <= 2.15e+99:
		tmp = t_2
	else:
		tmp = 0.5 * (im * math.pow(re, -0.5))
	return tmp
function code(re, im)
	t_0 = Float64(0.5 * sqrt(Float64(re * -4.0)))
	t_1 = Float64(0.5 * Float64(im / sqrt(re)))
	t_2 = Float64(0.5 * sqrt(Float64(im * 2.0)))
	tmp = 0.0
	if (re <= -2.4e+77)
		tmp = t_0;
	elseif (re <= -0.00022)
		tmp = t_2;
	elseif (re <= -1.75e-43)
		tmp = t_0;
	elseif (re <= 2.9e-52)
		tmp = t_2;
	elseif (re <= 1.45e+21)
		tmp = t_1;
	elseif (re <= 1.95e+58)
		tmp = t_2;
	elseif (re <= 5.6e+72)
		tmp = t_1;
	elseif (re <= 2.15e+99)
		tmp = t_2;
	else
		tmp = Float64(0.5 * Float64(im * (re ^ -0.5)));
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = 0.5 * sqrt((re * -4.0));
	t_1 = 0.5 * (im / sqrt(re));
	t_2 = 0.5 * sqrt((im * 2.0));
	tmp = 0.0;
	if (re <= -2.4e+77)
		tmp = t_0;
	elseif (re <= -0.00022)
		tmp = t_2;
	elseif (re <= -1.75e-43)
		tmp = t_0;
	elseif (re <= 2.9e-52)
		tmp = t_2;
	elseif (re <= 1.45e+21)
		tmp = t_1;
	elseif (re <= 1.95e+58)
		tmp = t_2;
	elseif (re <= 5.6e+72)
		tmp = t_1;
	elseif (re <= 2.15e+99)
		tmp = t_2;
	else
		tmp = 0.5 * (im * (re ^ -0.5));
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[re, -2.4e+77], t$95$0, If[LessEqual[re, -0.00022], t$95$2, If[LessEqual[re, -1.75e-43], t$95$0, If[LessEqual[re, 2.9e-52], t$95$2, If[LessEqual[re, 1.45e+21], t$95$1, If[LessEqual[re, 1.95e+58], t$95$2, If[LessEqual[re, 5.6e+72], t$95$1, If[LessEqual[re, 2.15e+99], t$95$2, N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\
t_1 := 0.5 \cdot \frac{im}{\sqrt{re}}\\
t_2 := 0.5 \cdot \sqrt{im \cdot 2}\\
\mathbf{if}\;re \leq -2.4 \cdot 10^{+77}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq -0.00022:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq -1.75 \cdot 10^{-43}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 2.9 \cdot 10^{-52}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq 1.45 \cdot 10^{+21}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;re \leq 5.6 \cdot 10^{+72}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq 2.15 \cdot 10^{+99}:\\
\;\;\;\;t\_2\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if re < -2.3999999999999999e77 or -2.20000000000000008e-4 < re < -1.74999999999999999e-43

    1. Initial program 32.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative83.1%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]

    if -2.3999999999999999e77 < re < -2.20000000000000008e-4 or -1.74999999999999999e-43 < re < 2.9000000000000002e-52 or 1.45e21 < re < 1.95000000000000005e58 or 5.5999999999999998e72 < re < 2.1500000000000001e99

    1. Initial program 59.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 75.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
    4. Step-by-step derivation
      1. *-commutative75.9%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
    5. Simplified75.9%

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

    if 2.9000000000000002e-52 < re < 1.45e21 or 1.95000000000000005e58 < re < 5.5999999999999998e72

    1. Initial program 27.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 28.4%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/228.4%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv28.4%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down33.1%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/233.1%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval33.1%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr33.1%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative33.1%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow233.1%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square76.5%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified76.5%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Step-by-step derivation
      1. *-commutative76.5%

        \[\leadsto 0.5 \cdot \color{blue}{\left(\left|im\right| \cdot {re}^{-0.5}\right)} \]
      2. metadata-eval76.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot {re}^{\color{blue}{\left(-0.5\right)}}\right) \]
      3. pow-flip76.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \color{blue}{\frac{1}{{re}^{0.5}}}\right) \]
      4. pow1/276.5%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \frac{1}{\color{blue}{\sqrt{re}}}\right) \]
      5. div-inv76.6%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\left|im\right|}{\sqrt{re}}} \]
      6. add-sqr-sqrt76.1%

        \[\leadsto 0.5 \cdot \frac{\left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|}{\sqrt{re}} \]
      7. fabs-sqr76.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{\sqrt{im} \cdot \sqrt{im}}}{\sqrt{re}} \]
      8. add-sqr-sqrt76.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    9. Applied egg-rr76.6%

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

    if 2.1500000000000001e99 < re

    1. Initial program 7.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 52.6%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/252.6%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv52.7%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down65.2%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/265.2%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow65.2%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow65.2%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval65.2%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr65.2%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative65.2%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow265.2%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square82.0%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified82.0%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Taylor expanded in re around 0 82.0%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{\frac{1}{re}} \cdot \left|im\right|\right)} \]
    9. Step-by-step derivation
      1. rem-square-sqrt81.6%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|\right) \]
      2. fabs-sqr81.6%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{\left(\sqrt{im} \cdot \sqrt{im}\right)}\right) \]
      3. rem-square-sqrt82.0%

        \[\leadsto 0.5 \cdot \left(\sqrt{\frac{1}{re}} \cdot \color{blue}{im}\right) \]
      4. unpow1/282.0%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{\left(\frac{1}{re}\right)}^{0.5}} \cdot im\right) \]
      5. rem-exp-log77.0%

        \[\leadsto 0.5 \cdot \left({\left(\frac{1}{\color{blue}{e^{\log re}}}\right)}^{0.5} \cdot im\right) \]
      6. exp-neg77.0%

        \[\leadsto 0.5 \cdot \left({\color{blue}{\left(e^{-\log re}\right)}}^{0.5} \cdot im\right) \]
      7. exp-prod77.0%

        \[\leadsto 0.5 \cdot \left(\color{blue}{e^{\left(-\log re\right) \cdot 0.5}} \cdot im\right) \]
      8. distribute-lft-neg-out77.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{-\log re \cdot 0.5}} \cdot im\right) \]
      9. distribute-rgt-neg-in77.0%

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{\log re \cdot \left(-0.5\right)}} \cdot im\right) \]
      10. metadata-eval77.0%

        \[\leadsto 0.5 \cdot \left(e^{\log re \cdot \color{blue}{-0.5}} \cdot im\right) \]
      11. exp-to-pow82.0%

        \[\leadsto 0.5 \cdot \left(\color{blue}{{re}^{-0.5}} \cdot im\right) \]
    10. Simplified82.0%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot im\right)} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification78.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -2.4 \cdot 10^{+77}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -0.00022:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq -1.75 \cdot 10^{-43}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq 2.9 \cdot 10^{-52}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq 1.45 \cdot 10^{+21}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 1.95 \cdot 10^{+58}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq 5.6 \cdot 10^{+72}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 2.15 \cdot 10^{+99}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 74.7% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\ t_1 := 0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{if}\;re \leq -4.1 \cdot 10^{+77}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq -1.15 \cdot 10^{-5}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq -1.6 \cdot 10^{-43}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 3.15 \cdot 10^{-52} \lor \neg \left(re \leq 1.75 \cdot 10^{+22}\right) \land \left(re \leq 1.3 \cdot 10^{+58} \lor \neg \left(re \leq 3.4 \cdot 10^{+70}\right) \land re \leq 1.46 \cdot 10^{+99}\right):\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (* 0.5 (sqrt (* re -4.0)))) (t_1 (* 0.5 (sqrt (* im 2.0)))))
   (if (<= re -4.1e+77)
     t_0
     (if (<= re -1.15e-5)
       t_1
       (if (<= re -1.6e-43)
         t_0
         (if (or (<= re 3.15e-52)
                 (and (not (<= re 1.75e+22))
                      (or (<= re 1.3e+58)
                          (and (not (<= re 3.4e+70)) (<= re 1.46e+99)))))
           t_1
           (* 0.5 (/ im (sqrt re)))))))))
double code(double re, double im) {
	double t_0 = 0.5 * sqrt((re * -4.0));
	double t_1 = 0.5 * sqrt((im * 2.0));
	double tmp;
	if (re <= -4.1e+77) {
		tmp = t_0;
	} else if (re <= -1.15e-5) {
		tmp = t_1;
	} else if (re <= -1.6e-43) {
		tmp = t_0;
	} else if ((re <= 3.15e-52) || (!(re <= 1.75e+22) && ((re <= 1.3e+58) || (!(re <= 3.4e+70) && (re <= 1.46e+99))))) {
		tmp = t_1;
	} else {
		tmp = 0.5 * (im / sqrt(re));
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = 0.5d0 * sqrt((re * (-4.0d0)))
    t_1 = 0.5d0 * sqrt((im * 2.0d0))
    if (re <= (-4.1d+77)) then
        tmp = t_0
    else if (re <= (-1.15d-5)) then
        tmp = t_1
    else if (re <= (-1.6d-43)) then
        tmp = t_0
    else if ((re <= 3.15d-52) .or. (.not. (re <= 1.75d+22)) .and. (re <= 1.3d+58) .or. (.not. (re <= 3.4d+70)) .and. (re <= 1.46d+99)) then
        tmp = t_1
    else
        tmp = 0.5d0 * (im / sqrt(re))
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = 0.5 * Math.sqrt((re * -4.0));
	double t_1 = 0.5 * Math.sqrt((im * 2.0));
	double tmp;
	if (re <= -4.1e+77) {
		tmp = t_0;
	} else if (re <= -1.15e-5) {
		tmp = t_1;
	} else if (re <= -1.6e-43) {
		tmp = t_0;
	} else if ((re <= 3.15e-52) || (!(re <= 1.75e+22) && ((re <= 1.3e+58) || (!(re <= 3.4e+70) && (re <= 1.46e+99))))) {
		tmp = t_1;
	} else {
		tmp = 0.5 * (im / Math.sqrt(re));
	}
	return tmp;
}
def code(re, im):
	t_0 = 0.5 * math.sqrt((re * -4.0))
	t_1 = 0.5 * math.sqrt((im * 2.0))
	tmp = 0
	if re <= -4.1e+77:
		tmp = t_0
	elif re <= -1.15e-5:
		tmp = t_1
	elif re <= -1.6e-43:
		tmp = t_0
	elif (re <= 3.15e-52) or (not (re <= 1.75e+22) and ((re <= 1.3e+58) or (not (re <= 3.4e+70) and (re <= 1.46e+99)))):
		tmp = t_1
	else:
		tmp = 0.5 * (im / math.sqrt(re))
	return tmp
function code(re, im)
	t_0 = Float64(0.5 * sqrt(Float64(re * -4.0)))
	t_1 = Float64(0.5 * sqrt(Float64(im * 2.0)))
	tmp = 0.0
	if (re <= -4.1e+77)
		tmp = t_0;
	elseif (re <= -1.15e-5)
		tmp = t_1;
	elseif (re <= -1.6e-43)
		tmp = t_0;
	elseif ((re <= 3.15e-52) || (!(re <= 1.75e+22) && ((re <= 1.3e+58) || (!(re <= 3.4e+70) && (re <= 1.46e+99)))))
		tmp = t_1;
	else
		tmp = Float64(0.5 * Float64(im / sqrt(re)));
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = 0.5 * sqrt((re * -4.0));
	t_1 = 0.5 * sqrt((im * 2.0));
	tmp = 0.0;
	if (re <= -4.1e+77)
		tmp = t_0;
	elseif (re <= -1.15e-5)
		tmp = t_1;
	elseif (re <= -1.6e-43)
		tmp = t_0;
	elseif ((re <= 3.15e-52) || (~((re <= 1.75e+22)) && ((re <= 1.3e+58) || (~((re <= 3.4e+70)) && (re <= 1.46e+99)))))
		tmp = t_1;
	else
		tmp = 0.5 * (im / sqrt(re));
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[re, -4.1e+77], t$95$0, If[LessEqual[re, -1.15e-5], t$95$1, If[LessEqual[re, -1.6e-43], t$95$0, If[Or[LessEqual[re, 3.15e-52], And[N[Not[LessEqual[re, 1.75e+22]], $MachinePrecision], Or[LessEqual[re, 1.3e+58], And[N[Not[LessEqual[re, 3.4e+70]], $MachinePrecision], LessEqual[re, 1.46e+99]]]]], t$95$1, N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \sqrt{re \cdot -4}\\
t_1 := 0.5 \cdot \sqrt{im \cdot 2}\\
\mathbf{if}\;re \leq -4.1 \cdot 10^{+77}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq -1.15 \cdot 10^{-5}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq -1.6 \cdot 10^{-43}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 3.15 \cdot 10^{-52} \lor \neg \left(re \leq 1.75 \cdot 10^{+22}\right) \land \left(re \leq 1.3 \cdot 10^{+58} \lor \neg \left(re \leq 3.4 \cdot 10^{+70}\right) \land re \leq 1.46 \cdot 10^{+99}\right):\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if re < -4.1000000000000001e77 or -1.15e-5 < re < -1.59999999999999992e-43

    1. Initial program 32.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative83.1%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]

    if -4.1000000000000001e77 < re < -1.15e-5 or -1.59999999999999992e-43 < re < 3.1500000000000002e-52 or 1.75e22 < re < 1.29999999999999994e58 or 3.4000000000000001e70 < re < 1.4600000000000001e99

    1. Initial program 59.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 75.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
    4. Step-by-step derivation
      1. *-commutative75.9%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
    5. Simplified75.9%

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

    if 3.1500000000000002e-52 < re < 1.75e22 or 1.29999999999999994e58 < re < 3.4000000000000001e70 or 1.4600000000000001e99 < re

    1. Initial program 14.3%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 44.7%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. pow1/244.7%

        \[\leadsto 0.5 \cdot \color{blue}{{\left(\frac{{im}^{2}}{re}\right)}^{0.5}} \]
      2. div-inv44.7%

        \[\leadsto 0.5 \cdot {\color{blue}{\left({im}^{2} \cdot \frac{1}{re}\right)}}^{0.5} \]
      3. unpow-prod-down54.7%

        \[\leadsto 0.5 \cdot \color{blue}{\left({\left({im}^{2}\right)}^{0.5} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right)} \]
      4. pow1/254.7%

        \[\leadsto 0.5 \cdot \left(\color{blue}{\sqrt{{im}^{2}}} \cdot {\left(\frac{1}{re}\right)}^{0.5}\right) \]
      5. inv-pow54.7%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {\color{blue}{\left({re}^{-1}\right)}}^{0.5}\right) \]
      6. pow-pow54.7%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot \color{blue}{{re}^{\left(-1 \cdot 0.5\right)}}\right) \]
      7. metadata-eval54.7%

        \[\leadsto 0.5 \cdot \left(\sqrt{{im}^{2}} \cdot {re}^{\color{blue}{-0.5}}\right) \]
    5. Applied egg-rr54.7%

      \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{{im}^{2}} \cdot {re}^{-0.5}\right)} \]
    6. Step-by-step derivation
      1. *-commutative54.7%

        \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \sqrt{{im}^{2}}\right)} \]
      2. unpow254.7%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \sqrt{\color{blue}{im \cdot im}}\right) \]
      3. rem-sqrt-square80.2%

        \[\leadsto 0.5 \cdot \left({re}^{-0.5} \cdot \color{blue}{\left|im\right|}\right) \]
    7. Simplified80.2%

      \[\leadsto 0.5 \cdot \color{blue}{\left({re}^{-0.5} \cdot \left|im\right|\right)} \]
    8. Step-by-step derivation
      1. *-commutative80.2%

        \[\leadsto 0.5 \cdot \color{blue}{\left(\left|im\right| \cdot {re}^{-0.5}\right)} \]
      2. metadata-eval80.2%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot {re}^{\color{blue}{\left(-0.5\right)}}\right) \]
      3. pow-flip80.2%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \color{blue}{\frac{1}{{re}^{0.5}}}\right) \]
      4. pow1/280.2%

        \[\leadsto 0.5 \cdot \left(\left|im\right| \cdot \frac{1}{\color{blue}{\sqrt{re}}}\right) \]
      5. div-inv80.2%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\left|im\right|}{\sqrt{re}}} \]
      6. add-sqr-sqrt79.8%

        \[\leadsto 0.5 \cdot \frac{\left|\color{blue}{\sqrt{im} \cdot \sqrt{im}}\right|}{\sqrt{re}} \]
      7. fabs-sqr79.8%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{\sqrt{im} \cdot \sqrt{im}}}{\sqrt{re}} \]
      8. add-sqr-sqrt80.2%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    9. Applied egg-rr80.2%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{im}{\sqrt{re}}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification78.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.1 \cdot 10^{+77}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq -1.15 \cdot 10^{-5}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{elif}\;re \leq -1.6 \cdot 10^{-43}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{elif}\;re \leq 3.15 \cdot 10^{-52} \lor \neg \left(re \leq 1.75 \cdot 10^{+22}\right) \land \left(re \leq 1.3 \cdot 10^{+58} \lor \neg \left(re \leq 3.4 \cdot 10^{+70}\right) \land re \leq 1.46 \cdot 10^{+99}\right):\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 62.9% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -5.8 \cdot 10^{+77} \lor \neg \left(re \leq -0.85\right) \land re \leq -1.7 \cdot 10^{-43}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (if (or (<= re -5.8e+77) (and (not (<= re -0.85)) (<= re -1.7e-43)))
   (* 0.5 (sqrt (* re -4.0)))
   (* 0.5 (sqrt (* im 2.0)))))
double code(double re, double im) {
	double tmp;
	if ((re <= -5.8e+77) || (!(re <= -0.85) && (re <= -1.7e-43))) {
		tmp = 0.5 * sqrt((re * -4.0));
	} else {
		tmp = 0.5 * sqrt((im * 2.0));
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if ((re <= (-5.8d+77)) .or. (.not. (re <= (-0.85d0))) .and. (re <= (-1.7d-43))) then
        tmp = 0.5d0 * sqrt((re * (-4.0d0)))
    else
        tmp = 0.5d0 * sqrt((im * 2.0d0))
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double tmp;
	if ((re <= -5.8e+77) || (!(re <= -0.85) && (re <= -1.7e-43))) {
		tmp = 0.5 * Math.sqrt((re * -4.0));
	} else {
		tmp = 0.5 * Math.sqrt((im * 2.0));
	}
	return tmp;
}
def code(re, im):
	tmp = 0
	if (re <= -5.8e+77) or (not (re <= -0.85) and (re <= -1.7e-43)):
		tmp = 0.5 * math.sqrt((re * -4.0))
	else:
		tmp = 0.5 * math.sqrt((im * 2.0))
	return tmp
function code(re, im)
	tmp = 0.0
	if ((re <= -5.8e+77) || (!(re <= -0.85) && (re <= -1.7e-43)))
		tmp = Float64(0.5 * sqrt(Float64(re * -4.0)));
	else
		tmp = Float64(0.5 * sqrt(Float64(im * 2.0)));
	end
	return tmp
end
function tmp_2 = code(re, im)
	tmp = 0.0;
	if ((re <= -5.8e+77) || (~((re <= -0.85)) && (re <= -1.7e-43)))
		tmp = 0.5 * sqrt((re * -4.0));
	else
		tmp = 0.5 * sqrt((im * 2.0));
	end
	tmp_2 = tmp;
end
code[re_, im_] := If[Or[LessEqual[re, -5.8e+77], And[N[Not[LessEqual[re, -0.85]], $MachinePrecision], LessEqual[re, -1.7e-43]]], N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;re \leq -5.8 \cdot 10^{+77} \lor \neg \left(re \leq -0.85\right) \land re \leq -1.7 \cdot 10^{-43}:\\
\;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < -5.8000000000000003e77 or -0.849999999999999978 < re < -1.7e-43

    1. Initial program 32.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative83.1%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified83.1%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]

    if -5.8000000000000003e77 < re < -0.849999999999999978 or -1.7e-43 < re

    1. Initial program 45.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 60.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
    4. Step-by-step derivation
      1. *-commutative60.8%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
    5. Simplified60.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification65.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -5.8 \cdot 10^{+77} \lor \neg \left(re \leq -0.85\right) \land re \leq -1.7 \cdot 10^{-43}:\\ \;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 51.4% accurate, 2.0× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \sqrt{im \cdot 2} \end{array} \]
(FPCore (re im) :precision binary64 (* 0.5 (sqrt (* im 2.0))))
double code(double re, double im) {
	return 0.5 * sqrt((im * 2.0));
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = 0.5d0 * sqrt((im * 2.0d0))
end function
public static double code(double re, double im) {
	return 0.5 * Math.sqrt((im * 2.0));
}
def code(re, im):
	return 0.5 * math.sqrt((im * 2.0))
function code(re, im)
	return Float64(0.5 * sqrt(Float64(im * 2.0)))
end
function tmp = code(re, im)
	tmp = 0.5 * sqrt((im * 2.0));
end
code[re_, im_] := N[(0.5 * N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \sqrt{im \cdot 2}
\end{array}
Derivation
  1. Initial program 42.8%

    \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in re around 0 52.7%

    \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
  4. Step-by-step derivation
    1. *-commutative52.7%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
  5. Simplified52.7%

    \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im \cdot 2}} \]
  6. Add Preprocessing

Reproduce

?
herbie shell --seed 2024107 
(FPCore (re im)
  :name "math.sqrt on complex, imaginary part, im greater than 0 branch"
  :precision binary64
  :pre (> im 0.0)
  (* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))