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

Percentage Accurate: 40.9% → 90.3%
Time: 12.5s
Alternatives: 8
Speedup: 1.9×

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 8 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: 40.9% 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: 90.3% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sqrt{re \cdot re + im \cdot im} - re \leq 0:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (if (<= (- (sqrt (+ (* re re) (* im im))) re) 0.0)
   (* 0.5 (/ im (sqrt re)))
   (sqrt (* 0.5 (- (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 / sqrt(re));
	} else {
		tmp = sqrt((0.5 * (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.sqrt(re));
	} else {
		tmp = Math.sqrt((0.5 * (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.sqrt(re))
	else:
		tmp = math.sqrt((0.5 * (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 / sqrt(re)));
	else
		tmp = sqrt(Float64(0.5 * 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 / sqrt(re));
	else
		tmp = sqrt((0.5 * (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[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(0.5 * N[(N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision] - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\sqrt{re \cdot re + im \cdot im} - re \leq 0:\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{0.5 \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 7.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 39.9%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div50.3%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow192.3%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval92.3%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow192.3%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. div-inv91.9%

        \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    5. Applied egg-rr91.9%

      \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/92.3%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{im \cdot 1}{\sqrt{re}}} \]
      2. *-rgt-identity92.3%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    7. Simplified92.3%

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

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

    1. Initial program 45.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow145.0%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr91.4%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow191.4%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative91.4%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*91.4%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval91.4%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified91.4%

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

Alternative 2: 73.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -9 \cdot 10^{-71}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 1.5 \cdot 10^{-148}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 1.46 \cdot 10^{-36}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 10^{+53}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 5 \cdot 10^{+94}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (if (<= re -9e-71)
   (sqrt (- re))
   (if (<= re 7.5e-180)
     (sqrt (* 0.5 (- im re)))
     (if (<= re 1.5e-148)
       (/ 0.5 (/ (sqrt re) im))
       (if (<= re 1.46e-36)
         (sqrt (* im 0.5))
         (if (<= re 1e+53)
           (* 0.5 (/ im (sqrt re)))
           (if (<= re 5e+94)
             (* 0.5 (sqrt (+ (* im 2.0) (* re (- (/ re im) 2.0)))))
             (/ (* im 0.5) (sqrt re)))))))))
double code(double re, double im) {
	double tmp;
	if (re <= -9e-71) {
		tmp = sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = sqrt((0.5 * (im - re)));
	} else if (re <= 1.5e-148) {
		tmp = 0.5 / (sqrt(re) / im);
	} else if (re <= 1.46e-36) {
		tmp = sqrt((im * 0.5));
	} else if (re <= 1e+53) {
		tmp = 0.5 * (im / sqrt(re));
	} else if (re <= 5e+94) {
		tmp = 0.5 * sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	} else {
		tmp = (im * 0.5) / sqrt(re);
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if (re <= (-9d-71)) then
        tmp = sqrt(-re)
    else if (re <= 7.5d-180) then
        tmp = sqrt((0.5d0 * (im - re)))
    else if (re <= 1.5d-148) then
        tmp = 0.5d0 / (sqrt(re) / im)
    else if (re <= 1.46d-36) then
        tmp = sqrt((im * 0.5d0))
    else if (re <= 1d+53) then
        tmp = 0.5d0 * (im / sqrt(re))
    else if (re <= 5d+94) then
        tmp = 0.5d0 * sqrt(((im * 2.0d0) + (re * ((re / im) - 2.0d0))))
    else
        tmp = (im * 0.5d0) / sqrt(re)
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double tmp;
	if (re <= -9e-71) {
		tmp = Math.sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = Math.sqrt((0.5 * (im - re)));
	} else if (re <= 1.5e-148) {
		tmp = 0.5 / (Math.sqrt(re) / im);
	} else if (re <= 1.46e-36) {
		tmp = Math.sqrt((im * 0.5));
	} else if (re <= 1e+53) {
		tmp = 0.5 * (im / Math.sqrt(re));
	} else if (re <= 5e+94) {
		tmp = 0.5 * Math.sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	} else {
		tmp = (im * 0.5) / Math.sqrt(re);
	}
	return tmp;
}
def code(re, im):
	tmp = 0
	if re <= -9e-71:
		tmp = math.sqrt(-re)
	elif re <= 7.5e-180:
		tmp = math.sqrt((0.5 * (im - re)))
	elif re <= 1.5e-148:
		tmp = 0.5 / (math.sqrt(re) / im)
	elif re <= 1.46e-36:
		tmp = math.sqrt((im * 0.5))
	elif re <= 1e+53:
		tmp = 0.5 * (im / math.sqrt(re))
	elif re <= 5e+94:
		tmp = 0.5 * math.sqrt(((im * 2.0) + (re * ((re / im) - 2.0))))
	else:
		tmp = (im * 0.5) / math.sqrt(re)
	return tmp
function code(re, im)
	tmp = 0.0
	if (re <= -9e-71)
		tmp = sqrt(Float64(-re));
	elseif (re <= 7.5e-180)
		tmp = sqrt(Float64(0.5 * Float64(im - re)));
	elseif (re <= 1.5e-148)
		tmp = Float64(0.5 / Float64(sqrt(re) / im));
	elseif (re <= 1.46e-36)
		tmp = sqrt(Float64(im * 0.5));
	elseif (re <= 1e+53)
		tmp = Float64(0.5 * Float64(im / sqrt(re)));
	elseif (re <= 5e+94)
		tmp = Float64(0.5 * sqrt(Float64(Float64(im * 2.0) + Float64(re * Float64(Float64(re / im) - 2.0)))));
	else
		tmp = Float64(Float64(im * 0.5) / sqrt(re));
	end
	return tmp
end
function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -9e-71)
		tmp = sqrt(-re);
	elseif (re <= 7.5e-180)
		tmp = sqrt((0.5 * (im - re)));
	elseif (re <= 1.5e-148)
		tmp = 0.5 / (sqrt(re) / im);
	elseif (re <= 1.46e-36)
		tmp = sqrt((im * 0.5));
	elseif (re <= 1e+53)
		tmp = 0.5 * (im / sqrt(re));
	elseif (re <= 5e+94)
		tmp = 0.5 * sqrt(((im * 2.0) + (re * ((re / im) - 2.0))));
	else
		tmp = (im * 0.5) / sqrt(re);
	end
	tmp_2 = tmp;
end
code[re_, im_] := If[LessEqual[re, -9e-71], N[Sqrt[(-re)], $MachinePrecision], If[LessEqual[re, 7.5e-180], N[Sqrt[N[(0.5 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[LessEqual[re, 1.5e-148], N[(0.5 / N[(N[Sqrt[re], $MachinePrecision] / im), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 1.46e-36], N[Sqrt[N[(im * 0.5), $MachinePrecision]], $MachinePrecision], If[LessEqual[re, 1e+53], N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 5e+94], 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], N[(N[(im * 0.5), $MachinePrecision] / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;re \leq -9 \cdot 10^{-71}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\
\;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\

\mathbf{elif}\;re \leq 1.5 \cdot 10^{-148}:\\
\;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\

\mathbf{elif}\;re \leq 1.46 \cdot 10^{-36}:\\
\;\;\;\;\sqrt{im \cdot 0.5}\\

\mathbf{elif}\;re \leq 10^{+53}:\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\

\mathbf{elif}\;re \leq 5 \cdot 10^{+94}:\\
\;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 7 regimes
  2. if re < -9.0000000000000004e-71

    1. Initial program 44.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative81.8%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt81.4%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod81.8%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative81.8%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt81.8%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval81.8%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr81.8%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*81.8%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval81.8%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg81.8%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified81.8%

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

    if -9.0000000000000004e-71 < re < 7.50000000000000015e-180

    1. Initial program 56.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow156.1%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr97.3%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow197.3%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative97.3%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*97.3%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval97.3%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified97.3%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 82.5%

      \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im + -1 \cdot re\right)}} \]
    8. Step-by-step derivation
      1. neg-mul-182.5%

        \[\leadsto \sqrt{0.5 \cdot \left(im + \color{blue}{\left(-re\right)}\right)} \]
      2. unsub-neg82.5%

        \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im - re\right)}} \]
    9. Simplified82.5%

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

    if 7.50000000000000015e-180 < re < 1.49999999999999999e-148

    1. Initial program 2.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 5.0%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div5.0%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval83.6%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. clear-num84.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    5. Applied egg-rr84.1%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    6. Step-by-step derivation
      1. un-div-inv84.1%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    7. Applied egg-rr84.1%

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

    if 1.49999999999999999e-148 < re < 1.4599999999999999e-36

    1. Initial program 38.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow138.9%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr61.8%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow161.8%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative61.8%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*61.8%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval61.8%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified61.8%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 63.2%

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

    if 1.4599999999999999e-36 < re < 9.9999999999999999e52

    1. Initial program 21.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 35.3%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div43.4%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow171.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval71.5%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow171.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. div-inv71.3%

        \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    5. Applied egg-rr71.3%

      \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/71.5%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{im \cdot 1}{\sqrt{re}}} \]
      2. *-rgt-identity71.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    7. Simplified71.5%

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

    if 9.9999999999999999e52 < re < 5.0000000000000001e94

    1. Initial program 40.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around 0 87.3%

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

    if 5.0000000000000001e94 < re

    1. Initial program 9.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 54.2%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div70.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow193.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval93.1%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow193.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. clear-num90.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    5. Applied egg-rr90.1%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    6. Step-by-step derivation
      1. un-div-inv90.1%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    7. Applied egg-rr90.1%

      \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    8. Step-by-step derivation
      1. associate-/r/93.0%

        \[\leadsto \color{blue}{\frac{0.5}{\sqrt{re}} \cdot im} \]
      2. associate-*l/93.1%

        \[\leadsto \color{blue}{\frac{0.5 \cdot im}{\sqrt{re}}} \]
      3. *-commutative93.1%

        \[\leadsto \frac{\color{blue}{im \cdot 0.5}}{\sqrt{re}} \]
    9. Simplified93.1%

      \[\leadsto \color{blue}{\frac{im \cdot 0.5}{\sqrt{re}}} \]
  3. Recombined 7 regimes into one program.
  4. Final simplification81.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -9 \cdot 10^{-71}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 1.5 \cdot 10^{-148}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 1.46 \cdot 10^{-36}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 10^{+53}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 5 \cdot 10^{+94}:\\ \;\;\;\;0.5 \cdot \sqrt{im \cdot 2 + re \cdot \left(\frac{re}{im} - 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 72.9% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{if}\;re \leq -3.9 \cdot 10^{-73}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 8 \cdot 10^{-149}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 6.6 \cdot 10^{-37}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 1.6 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (sqrt (* 0.5 (- im re)))))
   (if (<= re -3.9e-73)
     (sqrt (- re))
     (if (<= re 7.5e-180)
       t_0
       (if (<= re 8e-149)
         (/ 0.5 (/ (sqrt re) im))
         (if (<= re 6.6e-37)
           (sqrt (* im 0.5))
           (if (or (<= re 1.6e+53) (not (<= re 5.8e+93)))
             (* 0.5 (/ im (sqrt re)))
             t_0)))))))
double code(double re, double im) {
	double t_0 = sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -3.9e-73) {
		tmp = sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = t_0;
	} else if (re <= 8e-149) {
		tmp = 0.5 / (sqrt(re) / im);
	} else if (re <= 6.6e-37) {
		tmp = sqrt((im * 0.5));
	} else if ((re <= 1.6e+53) || !(re <= 5.8e+93)) {
		tmp = 0.5 * (im / sqrt(re));
	} else {
		tmp = t_0;
	}
	return tmp;
}
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((0.5d0 * (im - re)))
    if (re <= (-3.9d-73)) then
        tmp = sqrt(-re)
    else if (re <= 7.5d-180) then
        tmp = t_0
    else if (re <= 8d-149) then
        tmp = 0.5d0 / (sqrt(re) / im)
    else if (re <= 6.6d-37) then
        tmp = sqrt((im * 0.5d0))
    else if ((re <= 1.6d+53) .or. (.not. (re <= 5.8d+93))) then
        tmp = 0.5d0 * (im / sqrt(re))
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = Math.sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -3.9e-73) {
		tmp = Math.sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = t_0;
	} else if (re <= 8e-149) {
		tmp = 0.5 / (Math.sqrt(re) / im);
	} else if (re <= 6.6e-37) {
		tmp = Math.sqrt((im * 0.5));
	} else if ((re <= 1.6e+53) || !(re <= 5.8e+93)) {
		tmp = 0.5 * (im / Math.sqrt(re));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(re, im):
	t_0 = math.sqrt((0.5 * (im - re)))
	tmp = 0
	if re <= -3.9e-73:
		tmp = math.sqrt(-re)
	elif re <= 7.5e-180:
		tmp = t_0
	elif re <= 8e-149:
		tmp = 0.5 / (math.sqrt(re) / im)
	elif re <= 6.6e-37:
		tmp = math.sqrt((im * 0.5))
	elif (re <= 1.6e+53) or not (re <= 5.8e+93):
		tmp = 0.5 * (im / math.sqrt(re))
	else:
		tmp = t_0
	return tmp
function code(re, im)
	t_0 = sqrt(Float64(0.5 * Float64(im - re)))
	tmp = 0.0
	if (re <= -3.9e-73)
		tmp = sqrt(Float64(-re));
	elseif (re <= 7.5e-180)
		tmp = t_0;
	elseif (re <= 8e-149)
		tmp = Float64(0.5 / Float64(sqrt(re) / im));
	elseif (re <= 6.6e-37)
		tmp = sqrt(Float64(im * 0.5));
	elseif ((re <= 1.6e+53) || !(re <= 5.8e+93))
		tmp = Float64(0.5 * Float64(im / sqrt(re)));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = sqrt((0.5 * (im - re)));
	tmp = 0.0;
	if (re <= -3.9e-73)
		tmp = sqrt(-re);
	elseif (re <= 7.5e-180)
		tmp = t_0;
	elseif (re <= 8e-149)
		tmp = 0.5 / (sqrt(re) / im);
	elseif (re <= 6.6e-37)
		tmp = sqrt((im * 0.5));
	elseif ((re <= 1.6e+53) || ~((re <= 5.8e+93)))
		tmp = 0.5 * (im / sqrt(re));
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[Sqrt[N[(0.5 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[re, -3.9e-73], N[Sqrt[(-re)], $MachinePrecision], If[LessEqual[re, 7.5e-180], t$95$0, If[LessEqual[re, 8e-149], N[(0.5 / N[(N[Sqrt[re], $MachinePrecision] / im), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 6.6e-37], N[Sqrt[N[(im * 0.5), $MachinePrecision]], $MachinePrecision], If[Or[LessEqual[re, 1.6e+53], N[Not[LessEqual[re, 5.8e+93]], $MachinePrecision]], N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{0.5 \cdot \left(im - re\right)}\\
\mathbf{if}\;re \leq -3.9 \cdot 10^{-73}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 8 \cdot 10^{-149}:\\
\;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\

\mathbf{elif}\;re \leq 6.6 \cdot 10^{-37}:\\
\;\;\;\;\sqrt{im \cdot 0.5}\\

\mathbf{elif}\;re \leq 1.6 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 5 regimes
  2. if re < -3.89999999999999982e-73

    1. Initial program 44.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative81.8%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt81.4%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod81.8%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative81.8%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt81.8%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval81.8%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr81.8%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*81.8%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval81.8%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg81.8%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified81.8%

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

    if -3.89999999999999982e-73 < re < 7.50000000000000015e-180 or 1.6e53 < re < 5.7999999999999997e93

    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. Step-by-step derivation
      1. pow154.5%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr96.4%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow196.4%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative96.4%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*96.4%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval96.4%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified96.4%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 82.4%

      \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im + -1 \cdot re\right)}} \]
    8. Step-by-step derivation
      1. neg-mul-182.4%

        \[\leadsto \sqrt{0.5 \cdot \left(im + \color{blue}{\left(-re\right)}\right)} \]
      2. unsub-neg82.4%

        \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im - re\right)}} \]
    9. Simplified82.4%

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

    if 7.50000000000000015e-180 < re < 7.99999999999999983e-149

    1. Initial program 2.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 5.0%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div5.0%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval83.6%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. clear-num84.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    5. Applied egg-rr84.1%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    6. Step-by-step derivation
      1. un-div-inv84.1%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    7. Applied egg-rr84.1%

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

    if 7.99999999999999983e-149 < re < 6.59999999999999964e-37

    1. Initial program 38.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow138.9%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr61.8%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow161.8%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative61.8%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*61.8%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval61.8%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified61.8%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 63.2%

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

    if 6.59999999999999964e-37 < re < 1.6e53 or 5.7999999999999997e93 < re

    1. Initial program 13.5%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 47.7%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div61.0%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow185.7%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval85.7%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow185.7%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. div-inv85.5%

        \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    5. Applied egg-rr85.5%

      \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/85.7%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{im \cdot 1}{\sqrt{re}}} \]
      2. *-rgt-identity85.7%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    7. Simplified85.7%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{im}{\sqrt{re}}} \]
  3. Recombined 5 regimes into one program.
  4. Final simplification81.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -3.9 \cdot 10^{-73}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 8 \cdot 10^{-149}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 6.6 \cdot 10^{-37}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 1.6 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 73.1% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \frac{im}{\sqrt{re}}\\ t_1 := \sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{if}\;re \leq -3.75 \cdot 10^{-70}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 1.28 \cdot 10^{-36}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 1.65 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (* 0.5 (/ im (sqrt re)))) (t_1 (sqrt (* 0.5 (- im re)))))
   (if (<= re -3.75e-70)
     (sqrt (- re))
     (if (<= re 7.5e-180)
       t_1
       (if (<= re 7.6e-149)
         t_0
         (if (<= re 1.28e-36)
           (sqrt (* im 0.5))
           (if (or (<= re 1.65e+53) (not (<= re 5.8e+93))) t_0 t_1)))))))
double code(double re, double im) {
	double t_0 = 0.5 * (im / sqrt(re));
	double t_1 = sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -3.75e-70) {
		tmp = sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = t_1;
	} else if (re <= 7.6e-149) {
		tmp = t_0;
	} else if (re <= 1.28e-36) {
		tmp = sqrt((im * 0.5));
	} else if ((re <= 1.65e+53) || !(re <= 5.8e+93)) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	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 * (im / sqrt(re))
    t_1 = sqrt((0.5d0 * (im - re)))
    if (re <= (-3.75d-70)) then
        tmp = sqrt(-re)
    else if (re <= 7.5d-180) then
        tmp = t_1
    else if (re <= 7.6d-149) then
        tmp = t_0
    else if (re <= 1.28d-36) then
        tmp = sqrt((im * 0.5d0))
    else if ((re <= 1.65d+53) .or. (.not. (re <= 5.8d+93))) then
        tmp = t_0
    else
        tmp = t_1
    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 = Math.sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -3.75e-70) {
		tmp = Math.sqrt(-re);
	} else if (re <= 7.5e-180) {
		tmp = t_1;
	} else if (re <= 7.6e-149) {
		tmp = t_0;
	} else if (re <= 1.28e-36) {
		tmp = Math.sqrt((im * 0.5));
	} else if ((re <= 1.65e+53) || !(re <= 5.8e+93)) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(re, im):
	t_0 = 0.5 * (im / math.sqrt(re))
	t_1 = math.sqrt((0.5 * (im - re)))
	tmp = 0
	if re <= -3.75e-70:
		tmp = math.sqrt(-re)
	elif re <= 7.5e-180:
		tmp = t_1
	elif re <= 7.6e-149:
		tmp = t_0
	elif re <= 1.28e-36:
		tmp = math.sqrt((im * 0.5))
	elif (re <= 1.65e+53) or not (re <= 5.8e+93):
		tmp = t_0
	else:
		tmp = t_1
	return tmp
function code(re, im)
	t_0 = Float64(0.5 * Float64(im / sqrt(re)))
	t_1 = sqrt(Float64(0.5 * Float64(im - re)))
	tmp = 0.0
	if (re <= -3.75e-70)
		tmp = sqrt(Float64(-re));
	elseif (re <= 7.5e-180)
		tmp = t_1;
	elseif (re <= 7.6e-149)
		tmp = t_0;
	elseif (re <= 1.28e-36)
		tmp = sqrt(Float64(im * 0.5));
	elseif ((re <= 1.65e+53) || !(re <= 5.8e+93))
		tmp = t_0;
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = 0.5 * (im / sqrt(re));
	t_1 = sqrt((0.5 * (im - re)));
	tmp = 0.0;
	if (re <= -3.75e-70)
		tmp = sqrt(-re);
	elseif (re <= 7.5e-180)
		tmp = t_1;
	elseif (re <= 7.6e-149)
		tmp = t_0;
	elseif (re <= 1.28e-36)
		tmp = sqrt((im * 0.5));
	elseif ((re <= 1.65e+53) || ~((re <= 5.8e+93)))
		tmp = t_0;
	else
		tmp = t_1;
	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[Sqrt[N[(0.5 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[re, -3.75e-70], N[Sqrt[(-re)], $MachinePrecision], If[LessEqual[re, 7.5e-180], t$95$1, If[LessEqual[re, 7.6e-149], t$95$0, If[LessEqual[re, 1.28e-36], N[Sqrt[N[(im * 0.5), $MachinePrecision]], $MachinePrecision], If[Or[LessEqual[re, 1.65e+53], N[Not[LessEqual[re, 5.8e+93]], $MachinePrecision]], t$95$0, t$95$1]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \frac{im}{\sqrt{re}}\\
t_1 := \sqrt{0.5 \cdot \left(im - re\right)}\\
\mathbf{if}\;re \leq -3.75 \cdot 10^{-70}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 1.28 \cdot 10^{-36}:\\
\;\;\;\;\sqrt{im \cdot 0.5}\\

\mathbf{elif}\;re \leq 1.65 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\
\;\;\;\;t\_0\\

\mathbf{else}:\\
\;\;\;\;t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if re < -3.74999999999999986e-70

    1. Initial program 44.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative81.8%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt81.4%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod81.8%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative81.8%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt81.8%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval81.8%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr81.8%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*81.8%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval81.8%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg81.8%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified81.8%

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

    if -3.74999999999999986e-70 < re < 7.50000000000000015e-180 or 1.6500000000000001e53 < re < 5.7999999999999997e93

    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. Step-by-step derivation
      1. pow154.5%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr96.4%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow196.4%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative96.4%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*96.4%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval96.4%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified96.4%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 82.4%

      \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im + -1 \cdot re\right)}} \]
    8. Step-by-step derivation
      1. neg-mul-182.4%

        \[\leadsto \sqrt{0.5 \cdot \left(im + \color{blue}{\left(-re\right)}\right)} \]
      2. unsub-neg82.4%

        \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im - re\right)}} \]
    9. Simplified82.4%

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

    if 7.50000000000000015e-180 < re < 7.6000000000000001e-149 or 1.28e-36 < re < 1.6500000000000001e53 or 5.7999999999999997e93 < re

    1. Initial program 12.6%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 44.2%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div56.4%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow185.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval85.5%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow185.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. div-inv85.4%

        \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    5. Applied egg-rr85.4%

      \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/85.5%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{im \cdot 1}{\sqrt{re}}} \]
      2. *-rgt-identity85.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    7. Simplified85.5%

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

    if 7.6000000000000001e-149 < re < 1.28e-36

    1. Initial program 38.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow138.9%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr61.8%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow161.8%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative61.8%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*61.8%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval61.8%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified61.8%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 63.2%

      \[\leadsto \sqrt{0.5 \cdot \color{blue}{im}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification81.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -3.75 \cdot 10^{-70}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.5 \cdot 10^{-180}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 1.28 \cdot 10^{-36}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 1.65 \cdot 10^{+53} \lor \neg \left(re \leq 5.8 \cdot 10^{+93}\right):\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 73.0% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{if}\;re \leq -4.5 \cdot 10^{-70}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.4 \cdot 10^{-180}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 5.6 \cdot 10^{-37}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 2.8 \cdot 10^{+52}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 5.8 \cdot 10^{+93}:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (sqrt (* 0.5 (- im re)))))
   (if (<= re -4.5e-70)
     (sqrt (- re))
     (if (<= re 7.4e-180)
       t_0
       (if (<= re 7.6e-149)
         (/ 0.5 (/ (sqrt re) im))
         (if (<= re 5.6e-37)
           (sqrt (* im 0.5))
           (if (<= re 2.8e+52)
             (* 0.5 (/ im (sqrt re)))
             (if (<= re 5.8e+93) t_0 (/ (* im 0.5) (sqrt re))))))))))
double code(double re, double im) {
	double t_0 = sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -4.5e-70) {
		tmp = sqrt(-re);
	} else if (re <= 7.4e-180) {
		tmp = t_0;
	} else if (re <= 7.6e-149) {
		tmp = 0.5 / (sqrt(re) / im);
	} else if (re <= 5.6e-37) {
		tmp = sqrt((im * 0.5));
	} else if (re <= 2.8e+52) {
		tmp = 0.5 * (im / sqrt(re));
	} else if (re <= 5.8e+93) {
		tmp = t_0;
	} else {
		tmp = (im * 0.5) / 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) :: tmp
    t_0 = sqrt((0.5d0 * (im - re)))
    if (re <= (-4.5d-70)) then
        tmp = sqrt(-re)
    else if (re <= 7.4d-180) then
        tmp = t_0
    else if (re <= 7.6d-149) then
        tmp = 0.5d0 / (sqrt(re) / im)
    else if (re <= 5.6d-37) then
        tmp = sqrt((im * 0.5d0))
    else if (re <= 2.8d+52) then
        tmp = 0.5d0 * (im / sqrt(re))
    else if (re <= 5.8d+93) then
        tmp = t_0
    else
        tmp = (im * 0.5d0) / sqrt(re)
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double t_0 = Math.sqrt((0.5 * (im - re)));
	double tmp;
	if (re <= -4.5e-70) {
		tmp = Math.sqrt(-re);
	} else if (re <= 7.4e-180) {
		tmp = t_0;
	} else if (re <= 7.6e-149) {
		tmp = 0.5 / (Math.sqrt(re) / im);
	} else if (re <= 5.6e-37) {
		tmp = Math.sqrt((im * 0.5));
	} else if (re <= 2.8e+52) {
		tmp = 0.5 * (im / Math.sqrt(re));
	} else if (re <= 5.8e+93) {
		tmp = t_0;
	} else {
		tmp = (im * 0.5) / Math.sqrt(re);
	}
	return tmp;
}
def code(re, im):
	t_0 = math.sqrt((0.5 * (im - re)))
	tmp = 0
	if re <= -4.5e-70:
		tmp = math.sqrt(-re)
	elif re <= 7.4e-180:
		tmp = t_0
	elif re <= 7.6e-149:
		tmp = 0.5 / (math.sqrt(re) / im)
	elif re <= 5.6e-37:
		tmp = math.sqrt((im * 0.5))
	elif re <= 2.8e+52:
		tmp = 0.5 * (im / math.sqrt(re))
	elif re <= 5.8e+93:
		tmp = t_0
	else:
		tmp = (im * 0.5) / math.sqrt(re)
	return tmp
function code(re, im)
	t_0 = sqrt(Float64(0.5 * Float64(im - re)))
	tmp = 0.0
	if (re <= -4.5e-70)
		tmp = sqrt(Float64(-re));
	elseif (re <= 7.4e-180)
		tmp = t_0;
	elseif (re <= 7.6e-149)
		tmp = Float64(0.5 / Float64(sqrt(re) / im));
	elseif (re <= 5.6e-37)
		tmp = sqrt(Float64(im * 0.5));
	elseif (re <= 2.8e+52)
		tmp = Float64(0.5 * Float64(im / sqrt(re)));
	elseif (re <= 5.8e+93)
		tmp = t_0;
	else
		tmp = Float64(Float64(im * 0.5) / sqrt(re));
	end
	return tmp
end
function tmp_2 = code(re, im)
	t_0 = sqrt((0.5 * (im - re)));
	tmp = 0.0;
	if (re <= -4.5e-70)
		tmp = sqrt(-re);
	elseif (re <= 7.4e-180)
		tmp = t_0;
	elseif (re <= 7.6e-149)
		tmp = 0.5 / (sqrt(re) / im);
	elseif (re <= 5.6e-37)
		tmp = sqrt((im * 0.5));
	elseif (re <= 2.8e+52)
		tmp = 0.5 * (im / sqrt(re));
	elseif (re <= 5.8e+93)
		tmp = t_0;
	else
		tmp = (im * 0.5) / sqrt(re);
	end
	tmp_2 = tmp;
end
code[re_, im_] := Block[{t$95$0 = N[Sqrt[N[(0.5 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[re, -4.5e-70], N[Sqrt[(-re)], $MachinePrecision], If[LessEqual[re, 7.4e-180], t$95$0, If[LessEqual[re, 7.6e-149], N[(0.5 / N[(N[Sqrt[re], $MachinePrecision] / im), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 5.6e-37], N[Sqrt[N[(im * 0.5), $MachinePrecision]], $MachinePrecision], If[LessEqual[re, 2.8e+52], N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 5.8e+93], t$95$0, N[(N[(im * 0.5), $MachinePrecision] / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{0.5 \cdot \left(im - re\right)}\\
\mathbf{if}\;re \leq -4.5 \cdot 10^{-70}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{elif}\;re \leq 7.4 \cdot 10^{-180}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\
\;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\

\mathbf{elif}\;re \leq 5.6 \cdot 10^{-37}:\\
\;\;\;\;\sqrt{im \cdot 0.5}\\

\mathbf{elif}\;re \leq 2.8 \cdot 10^{+52}:\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\

\mathbf{elif}\;re \leq 5.8 \cdot 10^{+93}:\\
\;\;\;\;t\_0\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if re < -4.50000000000000022e-70

    1. Initial program 44.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative81.8%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified81.8%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt81.4%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod81.8%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative81.8%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr81.8%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt81.8%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval81.8%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr81.8%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*81.8%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval81.8%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative81.8%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg81.8%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified81.8%

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

    if -4.50000000000000022e-70 < re < 7.40000000000000032e-180 or 2.8e52 < re < 5.7999999999999997e93

    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. Step-by-step derivation
      1. pow154.5%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr96.4%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow196.4%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative96.4%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*96.4%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval96.4%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified96.4%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 82.4%

      \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im + -1 \cdot re\right)}} \]
    8. Step-by-step derivation
      1. neg-mul-182.4%

        \[\leadsto \sqrt{0.5 \cdot \left(im + \color{blue}{\left(-re\right)}\right)} \]
      2. unsub-neg82.4%

        \[\leadsto \sqrt{0.5 \cdot \color{blue}{\left(im - re\right)}} \]
    9. Simplified82.4%

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

    if 7.40000000000000032e-180 < re < 7.6000000000000001e-149

    1. Initial program 2.4%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 5.0%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div5.0%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval83.6%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow183.6%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. clear-num84.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    5. Applied egg-rr84.1%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    6. Step-by-step derivation
      1. un-div-inv84.1%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    7. Applied egg-rr84.1%

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

    if 7.6000000000000001e-149 < re < 5.6000000000000002e-37

    1. Initial program 38.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow138.9%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr61.8%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow161.8%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative61.8%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*61.8%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval61.8%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified61.8%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 63.2%

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

    if 5.6000000000000002e-37 < re < 2.8e52

    1. Initial program 21.9%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 35.3%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div43.4%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow171.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval71.5%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow171.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. div-inv71.3%

        \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    5. Applied egg-rr71.3%

      \[\leadsto 0.5 \cdot \color{blue}{\left(im \cdot \frac{1}{\sqrt{re}}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/71.5%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{im \cdot 1}{\sqrt{re}}} \]
      2. *-rgt-identity71.5%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
    7. Simplified71.5%

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

    if 5.7999999999999997e93 < re

    1. Initial program 9.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 54.2%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{\frac{{im}^{2}}{re}}} \]
    4. Step-by-step derivation
      1. sqrt-div70.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{\sqrt{{im}^{2}}}{\sqrt{re}}} \]
      2. sqrt-pow193.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{{im}^{\left(\frac{2}{2}\right)}}}{\sqrt{re}} \]
      3. metadata-eval93.1%

        \[\leadsto 0.5 \cdot \frac{{im}^{\color{blue}{1}}}{\sqrt{re}} \]
      4. pow193.1%

        \[\leadsto 0.5 \cdot \frac{\color{blue}{im}}{\sqrt{re}} \]
      5. clear-num90.1%

        \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    5. Applied egg-rr90.1%

      \[\leadsto 0.5 \cdot \color{blue}{\frac{1}{\frac{\sqrt{re}}{im}}} \]
    6. Step-by-step derivation
      1. un-div-inv90.1%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    7. Applied egg-rr90.1%

      \[\leadsto \color{blue}{\frac{0.5}{\frac{\sqrt{re}}{im}}} \]
    8. Step-by-step derivation
      1. associate-/r/93.0%

        \[\leadsto \color{blue}{\frac{0.5}{\sqrt{re}} \cdot im} \]
      2. associate-*l/93.1%

        \[\leadsto \color{blue}{\frac{0.5 \cdot im}{\sqrt{re}}} \]
      3. *-commutative93.1%

        \[\leadsto \frac{\color{blue}{im \cdot 0.5}}{\sqrt{re}} \]
    9. Simplified93.1%

      \[\leadsto \color{blue}{\frac{im \cdot 0.5}{\sqrt{re}}} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification81.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.5 \cdot 10^{-70}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 7.4 \cdot 10^{-180}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{elif}\;re \leq 7.6 \cdot 10^{-149}:\\ \;\;\;\;\frac{0.5}{\frac{\sqrt{re}}{im}}\\ \mathbf{elif}\;re \leq 5.6 \cdot 10^{-37}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{elif}\;re \leq 2.8 \cdot 10^{+52}:\\ \;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\ \mathbf{elif}\;re \leq 5.8 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{0.5 \cdot \left(im - re\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 61.6% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -2.9 \cdot 10^{-133}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 1.05 \cdot 10^{+143}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (if (<= re -2.9e-133)
   (sqrt (- re))
   (if (<= re 1.05e+143) (sqrt (* im 0.5)) 0.0)))
double code(double re, double im) {
	double tmp;
	if (re <= -2.9e-133) {
		tmp = sqrt(-re);
	} else if (re <= 1.05e+143) {
		tmp = sqrt((im * 0.5));
	} else {
		tmp = 0.0;
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if (re <= (-2.9d-133)) then
        tmp = sqrt(-re)
    else if (re <= 1.05d+143) then
        tmp = sqrt((im * 0.5d0))
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double tmp;
	if (re <= -2.9e-133) {
		tmp = Math.sqrt(-re);
	} else if (re <= 1.05e+143) {
		tmp = Math.sqrt((im * 0.5));
	} else {
		tmp = 0.0;
	}
	return tmp;
}
def code(re, im):
	tmp = 0
	if re <= -2.9e-133:
		tmp = math.sqrt(-re)
	elif re <= 1.05e+143:
		tmp = math.sqrt((im * 0.5))
	else:
		tmp = 0.0
	return tmp
function code(re, im)
	tmp = 0.0
	if (re <= -2.9e-133)
		tmp = sqrt(Float64(-re));
	elseif (re <= 1.05e+143)
		tmp = sqrt(Float64(im * 0.5));
	else
		tmp = 0.0;
	end
	return tmp
end
function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -2.9e-133)
		tmp = sqrt(-re);
	elseif (re <= 1.05e+143)
		tmp = sqrt((im * 0.5));
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
code[re_, im_] := If[LessEqual[re, -2.9e-133], N[Sqrt[(-re)], $MachinePrecision], If[LessEqual[re, 1.05e+143], N[Sqrt[N[(im * 0.5), $MachinePrecision]], $MachinePrecision], 0.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;re \leq -2.9 \cdot 10^{-133}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{elif}\;re \leq 1.05 \cdot 10^{+143}:\\
\;\;\;\;\sqrt{im \cdot 0.5}\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if re < -2.8999999999999998e-133

    1. Initial program 50.0%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 78.0%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative78.0%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified78.0%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt77.6%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod78.0%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative78.0%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative78.0%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr78.0%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt78.0%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval78.0%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr78.0%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*78.0%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval78.0%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative78.0%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg78.0%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified78.0%

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

    if -2.8999999999999998e-133 < re < 1.04999999999999994e143

    1. Initial program 38.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. pow138.7%

        \[\leadsto \color{blue}{{\left(0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\right)}^{1}} \]
    4. Applied egg-rr71.1%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}\right)}^{1}} \]
    5. Step-by-step derivation
      1. unpow171.1%

        \[\leadsto \color{blue}{\sqrt{\left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right) \cdot 0.25}} \]
      2. *-commutative71.1%

        \[\leadsto \sqrt{\color{blue}{0.25 \cdot \left(2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)\right)}} \]
      3. associate-*r*71.1%

        \[\leadsto \sqrt{\color{blue}{\left(0.25 \cdot 2\right) \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
      4. metadata-eval71.1%

        \[\leadsto \sqrt{\color{blue}{0.5} \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)} \]
    6. Simplified71.1%

      \[\leadsto \color{blue}{\sqrt{0.5 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}} \]
    7. Taylor expanded in re around 0 64.4%

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

    if 1.04999999999999994e143 < re

    1. Initial program 2.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 35.0%

      \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\color{blue}{re} - re\right)} \]
    4. Taylor expanded in re around 0 35.0%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification65.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -2.9 \cdot 10^{-133}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{elif}\;re \leq 1.05 \cdot 10^{+143}:\\ \;\;\;\;\sqrt{im \cdot 0.5}\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 30.7% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\sqrt{-re}\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
(FPCore (re im) :precision binary64 (if (<= re -5e-310) (sqrt (- re)) 0.0))
double code(double re, double im) {
	double tmp;
	if (re <= -5e-310) {
		tmp = sqrt(-re);
	} else {
		tmp = 0.0;
	}
	return tmp;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    real(8) :: tmp
    if (re <= (-5d-310)) then
        tmp = sqrt(-re)
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
public static double code(double re, double im) {
	double tmp;
	if (re <= -5e-310) {
		tmp = Math.sqrt(-re);
	} else {
		tmp = 0.0;
	}
	return tmp;
}
def code(re, im):
	tmp = 0
	if re <= -5e-310:
		tmp = math.sqrt(-re)
	else:
		tmp = 0.0
	return tmp
function code(re, im)
	tmp = 0.0
	if (re <= -5e-310)
		tmp = sqrt(Float64(-re));
	else
		tmp = 0.0;
	end
	return tmp
end
function tmp_2 = code(re, im)
	tmp = 0.0;
	if (re <= -5e-310)
		tmp = sqrt(-re);
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
code[re_, im_] := If[LessEqual[re, -5e-310], N[Sqrt[(-re)], $MachinePrecision], 0.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;re \leq -5 \cdot 10^{-310}:\\
\;\;\;\;\sqrt{-re}\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < -4.999999999999985e-310

    1. Initial program 49.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around -inf 64.4%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
    4. Step-by-step derivation
      1. *-commutative64.4%

        \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    5. Simplified64.4%

      \[\leadsto 0.5 \cdot \sqrt{\color{blue}{re \cdot -4}} \]
    6. Step-by-step derivation
      1. add-sqr-sqrt64.0%

        \[\leadsto \color{blue}{\sqrt{0.5 \cdot \sqrt{re \cdot -4}} \cdot \sqrt{0.5 \cdot \sqrt{re \cdot -4}}} \]
      2. sqrt-unprod64.4%

        \[\leadsto \color{blue}{\sqrt{\left(0.5 \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)}} \]
      3. *-commutative64.4%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)} \cdot \left(0.5 \cdot \sqrt{re \cdot -4}\right)} \]
      4. *-commutative64.4%

        \[\leadsto \sqrt{\left(\sqrt{re \cdot -4} \cdot 0.5\right) \cdot \color{blue}{\left(\sqrt{re \cdot -4} \cdot 0.5\right)}} \]
      5. swap-sqr64.4%

        \[\leadsto \sqrt{\color{blue}{\left(\sqrt{re \cdot -4} \cdot \sqrt{re \cdot -4}\right) \cdot \left(0.5 \cdot 0.5\right)}} \]
      6. add-sqr-sqrt64.4%

        \[\leadsto \sqrt{\color{blue}{\left(re \cdot -4\right)} \cdot \left(0.5 \cdot 0.5\right)} \]
      7. metadata-eval64.4%

        \[\leadsto \sqrt{\left(re \cdot -4\right) \cdot \color{blue}{0.25}} \]
    7. Applied egg-rr64.4%

      \[\leadsto \color{blue}{\sqrt{\left(re \cdot -4\right) \cdot 0.25}} \]
    8. Step-by-step derivation
      1. associate-*l*64.4%

        \[\leadsto \sqrt{\color{blue}{re \cdot \left(-4 \cdot 0.25\right)}} \]
      2. metadata-eval64.4%

        \[\leadsto \sqrt{re \cdot \color{blue}{-1}} \]
      3. *-commutative64.4%

        \[\leadsto \sqrt{\color{blue}{-1 \cdot re}} \]
      4. mul-1-neg64.4%

        \[\leadsto \sqrt{\color{blue}{-re}} \]
    9. Simplified64.4%

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

    if -4.999999999999985e-310 < re

    1. Initial program 27.1%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in re around inf 13.0%

      \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\color{blue}{re} - re\right)} \]
    4. Taylor expanded in re around 0 13.0%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 8: 6.3% accurate, 213.0× speedup?

\[\begin{array}{l} \\ 0 \end{array} \]
(FPCore (re im) :precision binary64 0.0)
double code(double re, double im) {
	return 0.0;
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = 0.0d0
end function
public static double code(double re, double im) {
	return 0.0;
}
def code(re, im):
	return 0.0
function code(re, im)
	return 0.0
end
function tmp = code(re, im)
	tmp = 0.0;
end
code[re_, im_] := 0.0
\begin{array}{l}

\\
0
\end{array}
Derivation
  1. Initial program 37.9%

    \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in re around inf 8.1%

    \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\color{blue}{re} - re\right)} \]
  4. Taylor expanded in re around 0 8.1%

    \[\leadsto \color{blue}{0} \]
  5. Add Preprocessing

Reproduce

?
herbie shell --seed 2024111 
(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)))))