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

Percentage Accurate: 41.7% → 87.8%
Time: 7.0s
Alternatives: 8
Speedup: 1.7×

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: 41.7% 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: 87.8% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\mathsf{hypot}\left(im, re\right)}\\ \mathbf{if}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(t\_0, t\_0, -re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \end{array} \]
(FPCore (re im)
 :precision binary64
 (let* ((t_0 (sqrt (hypot im re))))
   (if (<= re 4.2e-38)
     (* (sqrt (* (fma t_0 t_0 (- re)) 2.0)) 0.5)
     (* (sqrt (/ 1.0 re)) (* im 0.5)))))
double code(double re, double im) {
	double t_0 = sqrt(hypot(im, re));
	double tmp;
	if (re <= 4.2e-38) {
		tmp = sqrt((fma(t_0, t_0, -re) * 2.0)) * 0.5;
	} else {
		tmp = sqrt((1.0 / re)) * (im * 0.5);
	}
	return tmp;
}
function code(re, im)
	t_0 = sqrt(hypot(im, re))
	tmp = 0.0
	if (re <= 4.2e-38)
		tmp = Float64(sqrt(Float64(fma(t_0, t_0, Float64(-re)) * 2.0)) * 0.5);
	else
		tmp = Float64(sqrt(Float64(1.0 / re)) * Float64(im * 0.5));
	end
	return tmp
end
code[re_, im_] := Block[{t$95$0 = N[Sqrt[N[Sqrt[im ^ 2 + re ^ 2], $MachinePrecision]], $MachinePrecision]}, If[LessEqual[re, 4.2e-38], N[(N[Sqrt[N[(N[(t$95$0 * t$95$0 + (-re)), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(1.0 / re), $MachinePrecision]], $MachinePrecision] * N[(im * 0.5), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\mathsf{hypot}\left(im, re\right)}\\
\mathbf{if}\;re \leq 4.2 \cdot 10^{-38}:\\
\;\;\;\;\sqrt{\mathsf{fma}\left(t\_0, t\_0, -re\right) \cdot 2} \cdot 0.5\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < 4.20000000000000026e-38

    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. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(\sqrt{re \cdot re + im \cdot im} - re\right)}} \]
      2. sub-negN/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(\sqrt{re \cdot re + im \cdot im} + \left(\mathsf{neg}\left(re\right)\right)\right)}} \]
      3. lift-sqrt.f64N/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{\sqrt{re \cdot re + im \cdot im}} + \left(\mathsf{neg}\left(re\right)\right)\right)} \]
      4. pow1/2N/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{{\left(re \cdot re + im \cdot im\right)}^{\frac{1}{2}}} + \left(\mathsf{neg}\left(re\right)\right)\right)} \]
      5. sqr-powN/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{{\left(re \cdot re + im \cdot im\right)}^{\left(\frac{\frac{1}{2}}{2}\right)} \cdot {\left(re \cdot re + im \cdot im\right)}^{\left(\frac{\frac{1}{2}}{2}\right)}} + \left(\mathsf{neg}\left(re\right)\right)\right)} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\mathsf{fma}\left({\left(re \cdot re + im \cdot im\right)}^{\left(\frac{\frac{1}{2}}{2}\right)}, {\left(re \cdot re + im \cdot im\right)}^{\left(\frac{\frac{1}{2}}{2}\right)}, \mathsf{neg}\left(re\right)\right)}} \]
    4. Applied rewrites94.6%

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

    if 4.20000000000000026e-38 < re

    1. Initial program 15.9%

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

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right) \cdot \sqrt{\frac{1}{re}}\right)} \]
    4. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
      2. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
      3. associate-*r*N/A

        \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\left(im \cdot \sqrt{\frac{1}{2}}\right) \cdot \sqrt{2}\right)}\right) \cdot \sqrt{\frac{1}{re}} \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
      5. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
      6. lower-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right)} \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
      7. lower-*.f64N/A

        \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\left(im \cdot \sqrt{\frac{1}{2}}\right)}\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
      8. lower-sqrt.f64N/A

        \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \color{blue}{\sqrt{\frac{1}{2}}}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
      9. lower-sqrt.f64N/A

        \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot \sqrt{\frac{1}{re}} \]
      10. lower-sqrt.f64N/A

        \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right) \cdot \color{blue}{\sqrt{\frac{1}{re}}} \]
      11. lower-/.f6476.8

        \[\leadsto \left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
    5. Applied rewrites76.8%

      \[\leadsto \color{blue}{\left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}}} \]
    6. Step-by-step derivation
      1. Applied rewrites77.2%

        \[\leadsto \left(im \cdot 0.5\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
    7. Recombined 2 regimes into one program.
    8. Final simplification90.2%

      \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\sqrt{\mathsf{hypot}\left(im, re\right)}, \sqrt{\mathsf{hypot}\left(im, re\right)}, -re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \]
    9. Add Preprocessing

    Alternative 2: 79.1% accurate, 0.8× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -1.96 \cdot 10^{+114}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq -1.9 \cdot 10^{-154}:\\ \;\;\;\;\sqrt{\left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} - re\right) \cdot 2} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{re}{im} - 2, re, im \cdot 2\right)} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \end{array} \]
    (FPCore (re im)
     :precision binary64
     (if (<= re -1.96e+114)
       (* (sqrt (* -4.0 re)) 0.5)
       (if (<= re -1.9e-154)
         (* (sqrt (* (- (sqrt (fma re re (* im im))) re) 2.0)) 0.5)
         (if (<= re 4.2e-38)
           (* (sqrt (fma (- (/ re im) 2.0) re (* im 2.0))) 0.5)
           (* (sqrt (/ 1.0 re)) (* im 0.5))))))
    double code(double re, double im) {
    	double tmp;
    	if (re <= -1.96e+114) {
    		tmp = sqrt((-4.0 * re)) * 0.5;
    	} else if (re <= -1.9e-154) {
    		tmp = sqrt(((sqrt(fma(re, re, (im * im))) - re) * 2.0)) * 0.5;
    	} else if (re <= 4.2e-38) {
    		tmp = sqrt(fma(((re / im) - 2.0), re, (im * 2.0))) * 0.5;
    	} else {
    		tmp = sqrt((1.0 / re)) * (im * 0.5);
    	}
    	return tmp;
    }
    
    function code(re, im)
    	tmp = 0.0
    	if (re <= -1.96e+114)
    		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
    	elseif (re <= -1.9e-154)
    		tmp = Float64(sqrt(Float64(Float64(sqrt(fma(re, re, Float64(im * im))) - re) * 2.0)) * 0.5);
    	elseif (re <= 4.2e-38)
    		tmp = Float64(sqrt(fma(Float64(Float64(re / im) - 2.0), re, Float64(im * 2.0))) * 0.5);
    	else
    		tmp = Float64(sqrt(Float64(1.0 / re)) * Float64(im * 0.5));
    	end
    	return tmp
    end
    
    code[re_, im_] := If[LessEqual[re, -1.96e+114], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, -1.9e-154], N[(N[Sqrt[N[(N[(N[Sqrt[N[(re * re + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 4.2e-38], N[(N[Sqrt[N[(N[(N[(re / im), $MachinePrecision] - 2.0), $MachinePrecision] * re + N[(im * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(1.0 / re), $MachinePrecision]], $MachinePrecision] * N[(im * 0.5), $MachinePrecision]), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;re \leq -1.96 \cdot 10^{+114}:\\
    \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
    
    \mathbf{elif}\;re \leq -1.9 \cdot 10^{-154}:\\
    \;\;\;\;\sqrt{\left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} - re\right) \cdot 2} \cdot 0.5\\
    
    \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\
    \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{re}{im} - 2, re, im \cdot 2\right)} \cdot 0.5\\
    
    \mathbf{else}:\\
    \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 4 regimes
    2. if re < -1.96000000000000009e114

      1. Initial program 28.2%

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

        \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
      4. Step-by-step derivation
        1. lower-*.f6488.4

          \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
      5. Applied rewrites88.4%

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

      if -1.96000000000000009e114 < re < -1.90000000000000005e-154

      1. Initial program 85.4%

        \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} - re\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{re \cdot re} + im \cdot im} - re\right)} \]
        3. lower-fma.f6485.4

          \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(re, re, im \cdot im\right)}} - re\right)} \]
      4. Applied rewrites85.4%

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

      if -1.90000000000000005e-154 < re < 4.20000000000000026e-38

      1. Initial program 47.2%

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

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

          \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{re \cdot \left(\frac{re}{im} - 2\right) + 2 \cdot im}} \]
        2. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{\left(\frac{re}{im} - 2\right) \cdot re} + 2 \cdot im} \]
        3. lower-fma.f64N/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{\mathsf{fma}\left(\frac{re}{im} - 2, re, 2 \cdot im\right)}} \]
        4. lower--.f64N/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\color{blue}{\frac{re}{im} - 2}, re, 2 \cdot im\right)} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\color{blue}{\frac{re}{im}} - 2, re, 2 \cdot im\right)} \]
        6. lower-*.f6485.9

          \[\leadsto 0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} - 2, re, \color{blue}{2 \cdot im}\right)} \]
      5. Applied rewrites85.9%

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

      if 4.20000000000000026e-38 < re

      1. Initial program 15.9%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right) \cdot \sqrt{\frac{1}{re}}\right)} \]
      4. Step-by-step derivation
        1. associate-*r*N/A

          \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
        2. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
        3. associate-*r*N/A

          \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\left(im \cdot \sqrt{\frac{1}{2}}\right) \cdot \sqrt{2}\right)}\right) \cdot \sqrt{\frac{1}{re}} \]
        4. associate-*r*N/A

          \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
        5. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
        6. lower-*.f64N/A

          \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right)} \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
        7. lower-*.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\left(im \cdot \sqrt{\frac{1}{2}}\right)}\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
        8. lower-sqrt.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \color{blue}{\sqrt{\frac{1}{2}}}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
        9. lower-sqrt.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot \sqrt{\frac{1}{re}} \]
        10. lower-sqrt.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right) \cdot \color{blue}{\sqrt{\frac{1}{re}}} \]
        11. lower-/.f6476.8

          \[\leadsto \left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
      5. Applied rewrites76.8%

        \[\leadsto \color{blue}{\left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}}} \]
      6. Step-by-step derivation
        1. Applied rewrites77.2%

          \[\leadsto \left(im \cdot 0.5\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
      7. Recombined 4 regimes into one program.
      8. Final simplification84.0%

        \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -1.96 \cdot 10^{+114}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq -1.9 \cdot 10^{-154}:\\ \;\;\;\;\sqrt{\left(\sqrt{\mathsf{fma}\left(re, re, im \cdot im\right)} - re\right) \cdot 2} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{re}{im} - 2, re, im \cdot 2\right)} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \]
      9. Add Preprocessing

      Alternative 3: 76.5% accurate, 1.1× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \end{array} \]
      (FPCore (re im)
       :precision binary64
       (if (<= re -4.8e+56)
         (* (sqrt (* -4.0 re)) 0.5)
         (if (<= re 4.2e-38)
           (* (sqrt (* (- im re) 2.0)) 0.5)
           (* (sqrt (/ 1.0 re)) (* im 0.5)))))
      double code(double re, double im) {
      	double tmp;
      	if (re <= -4.8e+56) {
      		tmp = sqrt((-4.0 * re)) * 0.5;
      	} else if (re <= 4.2e-38) {
      		tmp = sqrt(((im - re) * 2.0)) * 0.5;
      	} else {
      		tmp = sqrt((1.0 / re)) * (im * 0.5);
      	}
      	return tmp;
      }
      
      real(8) function code(re, im)
          real(8), intent (in) :: re
          real(8), intent (in) :: im
          real(8) :: tmp
          if (re <= (-4.8d+56)) then
              tmp = sqrt(((-4.0d0) * re)) * 0.5d0
          else if (re <= 4.2d-38) then
              tmp = sqrt(((im - re) * 2.0d0)) * 0.5d0
          else
              tmp = sqrt((1.0d0 / re)) * (im * 0.5d0)
          end if
          code = tmp
      end function
      
      public static double code(double re, double im) {
      	double tmp;
      	if (re <= -4.8e+56) {
      		tmp = Math.sqrt((-4.0 * re)) * 0.5;
      	} else if (re <= 4.2e-38) {
      		tmp = Math.sqrt(((im - re) * 2.0)) * 0.5;
      	} else {
      		tmp = Math.sqrt((1.0 / re)) * (im * 0.5);
      	}
      	return tmp;
      }
      
      def code(re, im):
      	tmp = 0
      	if re <= -4.8e+56:
      		tmp = math.sqrt((-4.0 * re)) * 0.5
      	elif re <= 4.2e-38:
      		tmp = math.sqrt(((im - re) * 2.0)) * 0.5
      	else:
      		tmp = math.sqrt((1.0 / re)) * (im * 0.5)
      	return tmp
      
      function code(re, im)
      	tmp = 0.0
      	if (re <= -4.8e+56)
      		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
      	elseif (re <= 4.2e-38)
      		tmp = Float64(sqrt(Float64(Float64(im - re) * 2.0)) * 0.5);
      	else
      		tmp = Float64(sqrt(Float64(1.0 / re)) * Float64(im * 0.5));
      	end
      	return tmp
      end
      
      function tmp_2 = code(re, im)
      	tmp = 0.0;
      	if (re <= -4.8e+56)
      		tmp = sqrt((-4.0 * re)) * 0.5;
      	elseif (re <= 4.2e-38)
      		tmp = sqrt(((im - re) * 2.0)) * 0.5;
      	else
      		tmp = sqrt((1.0 / re)) * (im * 0.5);
      	end
      	tmp_2 = tmp;
      end
      
      code[re_, im_] := If[LessEqual[re, -4.8e+56], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 4.2e-38], N[(N[Sqrt[N[(N[(im - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(1.0 / re), $MachinePrecision]], $MachinePrecision] * N[(im * 0.5), $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\
      \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
      
      \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\
      \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\
      
      \mathbf{else}:\\
      \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if re < -4.80000000000000027e56

        1. Initial program 41.4%

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

          \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
        4. Step-by-step derivation
          1. lower-*.f6489.0

            \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
        5. Applied rewrites89.0%

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

        if -4.80000000000000027e56 < re < 4.20000000000000026e-38

        1. Initial program 59.7%

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

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

            \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(im + \color{blue}{\left(\mathsf{neg}\left(re\right)\right)}\right)} \]
          2. unsub-negN/A

            \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
          3. lower--.f6479.1

            \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
        5. Applied rewrites79.1%

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

        if 4.20000000000000026e-38 < re

        1. Initial program 15.9%

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

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right) \cdot \sqrt{\frac{1}{re}}\right)} \]
        4. Step-by-step derivation
          1. associate-*r*N/A

            \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
          2. lower-*.f64N/A

            \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
          3. associate-*r*N/A

            \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\left(im \cdot \sqrt{\frac{1}{2}}\right) \cdot \sqrt{2}\right)}\right) \cdot \sqrt{\frac{1}{re}} \]
          4. associate-*r*N/A

            \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
          5. lower-*.f64N/A

            \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
          6. lower-*.f64N/A

            \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right)} \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
          7. lower-*.f64N/A

            \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\left(im \cdot \sqrt{\frac{1}{2}}\right)}\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
          8. lower-sqrt.f64N/A

            \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \color{blue}{\sqrt{\frac{1}{2}}}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
          9. lower-sqrt.f64N/A

            \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot \sqrt{\frac{1}{re}} \]
          10. lower-sqrt.f64N/A

            \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right) \cdot \color{blue}{\sqrt{\frac{1}{re}}} \]
          11. lower-/.f6476.8

            \[\leadsto \left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
        5. Applied rewrites76.8%

          \[\leadsto \color{blue}{\left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}}} \]
        6. Step-by-step derivation
          1. Applied rewrites77.2%

            \[\leadsto \left(im \cdot 0.5\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
        7. Recombined 3 regimes into one program.
        8. Final simplification80.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 76.5% accurate, 1.2× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \end{array} \]
        (FPCore (re im)
         :precision binary64
         (if (<= re -4.8e+56)
           (* (sqrt (* -4.0 re)) 0.5)
           (if (<= re 4.2e-38)
             (* (sqrt (* (- im re) 2.0)) 0.5)
             (/ (* im 0.5) (sqrt re)))))
        double code(double re, double im) {
        	double tmp;
        	if (re <= -4.8e+56) {
        		tmp = sqrt((-4.0 * re)) * 0.5;
        	} else if (re <= 4.2e-38) {
        		tmp = sqrt(((im - re) * 2.0)) * 0.5;
        	} 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 <= (-4.8d+56)) then
                tmp = sqrt(((-4.0d0) * re)) * 0.5d0
            else if (re <= 4.2d-38) then
                tmp = sqrt(((im - re) * 2.0d0)) * 0.5d0
            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 <= -4.8e+56) {
        		tmp = Math.sqrt((-4.0 * re)) * 0.5;
        	} else if (re <= 4.2e-38) {
        		tmp = Math.sqrt(((im - re) * 2.0)) * 0.5;
        	} else {
        		tmp = (im * 0.5) / Math.sqrt(re);
        	}
        	return tmp;
        }
        
        def code(re, im):
        	tmp = 0
        	if re <= -4.8e+56:
        		tmp = math.sqrt((-4.0 * re)) * 0.5
        	elif re <= 4.2e-38:
        		tmp = math.sqrt(((im - re) * 2.0)) * 0.5
        	else:
        		tmp = (im * 0.5) / math.sqrt(re)
        	return tmp
        
        function code(re, im)
        	tmp = 0.0
        	if (re <= -4.8e+56)
        		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
        	elseif (re <= 4.2e-38)
        		tmp = Float64(sqrt(Float64(Float64(im - re) * 2.0)) * 0.5);
        	else
        		tmp = Float64(Float64(im * 0.5) / sqrt(re));
        	end
        	return tmp
        end
        
        function tmp_2 = code(re, im)
        	tmp = 0.0;
        	if (re <= -4.8e+56)
        		tmp = sqrt((-4.0 * re)) * 0.5;
        	elseif (re <= 4.2e-38)
        		tmp = sqrt(((im - re) * 2.0)) * 0.5;
        	else
        		tmp = (im * 0.5) / sqrt(re);
        	end
        	tmp_2 = tmp;
        end
        
        code[re_, im_] := If[LessEqual[re, -4.8e+56], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 4.2e-38], N[(N[Sqrt[N[(N[(im - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[(im * 0.5), $MachinePrecision] / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\
        \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
        
        \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\
        \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if re < -4.80000000000000027e56

          1. Initial program 41.4%

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

            \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
          4. Step-by-step derivation
            1. lower-*.f6489.0

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
          5. Applied rewrites89.0%

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

          if -4.80000000000000027e56 < re < 4.20000000000000026e-38

          1. Initial program 59.7%

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

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(im + \color{blue}{\left(\mathsf{neg}\left(re\right)\right)}\right)} \]
            2. unsub-negN/A

              \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
            3. lower--.f6479.1

              \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
          5. Applied rewrites79.1%

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

          if 4.20000000000000026e-38 < re

          1. Initial program 15.9%

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

            \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right) \cdot \sqrt{\frac{1}{re}}\right)} \]
          4. Step-by-step derivation
            1. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
            2. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
            3. associate-*r*N/A

              \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\left(im \cdot \sqrt{\frac{1}{2}}\right) \cdot \sqrt{2}\right)}\right) \cdot \sqrt{\frac{1}{re}} \]
            4. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
            5. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
            6. lower-*.f64N/A

              \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right)} \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
            7. lower-*.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\left(im \cdot \sqrt{\frac{1}{2}}\right)}\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
            8. lower-sqrt.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \color{blue}{\sqrt{\frac{1}{2}}}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
            9. lower-sqrt.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot \sqrt{\frac{1}{re}} \]
            10. lower-sqrt.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right) \cdot \color{blue}{\sqrt{\frac{1}{re}}} \]
            11. lower-/.f6476.8

              \[\leadsto \left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
          5. Applied rewrites76.8%

            \[\leadsto \color{blue}{\left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}}} \]
          6. Step-by-step derivation
            1. Applied rewrites77.1%

              \[\leadsto \frac{0.5 \cdot im}{\color{blue}{\sqrt{re}}} \]
          7. Recombined 3 regimes into one program.
          8. Final simplification80.5%

            \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{im \cdot 0.5}{\sqrt{re}}\\ \end{array} \]
          9. Add Preprocessing

          Alternative 5: 76.5% accurate, 1.2× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{\sqrt{re}} \cdot im\\ \end{array} \end{array} \]
          (FPCore (re im)
           :precision binary64
           (if (<= re -4.8e+56)
             (* (sqrt (* -4.0 re)) 0.5)
             (if (<= re 4.2e-38)
               (* (sqrt (* (- im re) 2.0)) 0.5)
               (* (/ 0.5 (sqrt re)) im))))
          double code(double re, double im) {
          	double tmp;
          	if (re <= -4.8e+56) {
          		tmp = sqrt((-4.0 * re)) * 0.5;
          	} else if (re <= 4.2e-38) {
          		tmp = sqrt(((im - re) * 2.0)) * 0.5;
          	} else {
          		tmp = (0.5 / sqrt(re)) * im;
          	}
          	return tmp;
          }
          
          real(8) function code(re, im)
              real(8), intent (in) :: re
              real(8), intent (in) :: im
              real(8) :: tmp
              if (re <= (-4.8d+56)) then
                  tmp = sqrt(((-4.0d0) * re)) * 0.5d0
              else if (re <= 4.2d-38) then
                  tmp = sqrt(((im - re) * 2.0d0)) * 0.5d0
              else
                  tmp = (0.5d0 / sqrt(re)) * im
              end if
              code = tmp
          end function
          
          public static double code(double re, double im) {
          	double tmp;
          	if (re <= -4.8e+56) {
          		tmp = Math.sqrt((-4.0 * re)) * 0.5;
          	} else if (re <= 4.2e-38) {
          		tmp = Math.sqrt(((im - re) * 2.0)) * 0.5;
          	} else {
          		tmp = (0.5 / Math.sqrt(re)) * im;
          	}
          	return tmp;
          }
          
          def code(re, im):
          	tmp = 0
          	if re <= -4.8e+56:
          		tmp = math.sqrt((-4.0 * re)) * 0.5
          	elif re <= 4.2e-38:
          		tmp = math.sqrt(((im - re) * 2.0)) * 0.5
          	else:
          		tmp = (0.5 / math.sqrt(re)) * im
          	return tmp
          
          function code(re, im)
          	tmp = 0.0
          	if (re <= -4.8e+56)
          		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
          	elseif (re <= 4.2e-38)
          		tmp = Float64(sqrt(Float64(Float64(im - re) * 2.0)) * 0.5);
          	else
          		tmp = Float64(Float64(0.5 / sqrt(re)) * im);
          	end
          	return tmp
          end
          
          function tmp_2 = code(re, im)
          	tmp = 0.0;
          	if (re <= -4.8e+56)
          		tmp = sqrt((-4.0 * re)) * 0.5;
          	elseif (re <= 4.2e-38)
          		tmp = sqrt(((im - re) * 2.0)) * 0.5;
          	else
          		tmp = (0.5 / sqrt(re)) * im;
          	end
          	tmp_2 = tmp;
          end
          
          code[re_, im_] := If[LessEqual[re, -4.8e+56], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 4.2e-38], N[(N[Sqrt[N[(N[(im - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[(0.5 / N[Sqrt[re], $MachinePrecision]), $MachinePrecision] * im), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\
          \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
          
          \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\
          \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\
          
          \mathbf{else}:\\
          \;\;\;\;\frac{0.5}{\sqrt{re}} \cdot im\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if re < -4.80000000000000027e56

            1. Initial program 41.4%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
            4. Step-by-step derivation
              1. lower-*.f6489.0

                \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
            5. Applied rewrites89.0%

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

            if -4.80000000000000027e56 < re < 4.20000000000000026e-38

            1. Initial program 59.7%

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

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(im + \color{blue}{\left(\mathsf{neg}\left(re\right)\right)}\right)} \]
              2. unsub-negN/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
              3. lower--.f6479.1

                \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
            5. Applied rewrites79.1%

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

            if 4.20000000000000026e-38 < re

            1. Initial program 15.9%

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

              \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right) \cdot \sqrt{\frac{1}{re}}\right)} \]
            4. Step-by-step derivation
              1. associate-*r*N/A

                \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
              2. lower-*.f64N/A

                \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \left(\sqrt{\frac{1}{2}} \cdot \sqrt{2}\right)\right)\right) \cdot \sqrt{\frac{1}{re}}} \]
              3. associate-*r*N/A

                \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\left(im \cdot \sqrt{\frac{1}{2}}\right) \cdot \sqrt{2}\right)}\right) \cdot \sqrt{\frac{1}{re}} \]
              4. associate-*r*N/A

                \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
              5. lower-*.f64N/A

                \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right)} \cdot \sqrt{\frac{1}{re}} \]
              6. lower-*.f64N/A

                \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right)} \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
              7. lower-*.f64N/A

                \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\left(im \cdot \sqrt{\frac{1}{2}}\right)}\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
              8. lower-sqrt.f64N/A

                \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \color{blue}{\sqrt{\frac{1}{2}}}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}} \]
              9. lower-sqrt.f64N/A

                \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot \sqrt{\frac{1}{re}} \]
              10. lower-sqrt.f64N/A

                \[\leadsto \left(\left(\frac{1}{2} \cdot \left(im \cdot \sqrt{\frac{1}{2}}\right)\right) \cdot \sqrt{2}\right) \cdot \color{blue}{\sqrt{\frac{1}{re}}} \]
              11. lower-/.f6476.8

                \[\leadsto \left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
            5. Applied rewrites76.8%

              \[\leadsto \color{blue}{\left(\left(0.5 \cdot \left(im \cdot \sqrt{0.5}\right)\right) \cdot \sqrt{2}\right) \cdot \sqrt{\frac{1}{re}}} \]
            6. Step-by-step derivation
              1. Applied rewrites77.2%

                \[\leadsto \left(im \cdot 0.5\right) \cdot \sqrt{\color{blue}{\frac{1}{re}}} \]
              2. Step-by-step derivation
                1. Applied rewrites77.1%

                  \[\leadsto \frac{0.5}{\sqrt{re}} \cdot \color{blue}{im} \]
              3. Recombined 3 regimes into one program.
              4. Final simplification80.5%

                \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{elif}\;re \leq 4.2 \cdot 10^{-38}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{\sqrt{re}} \cdot im\\ \end{array} \]
              5. Add Preprocessing

              Alternative 6: 63.5% accurate, 1.6× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]
              (FPCore (re im)
               :precision binary64
               (if (<= re -4.8e+56)
                 (* (sqrt (* -4.0 re)) 0.5)
                 (* (sqrt (* (- im re) 2.0)) 0.5)))
              double code(double re, double im) {
              	double tmp;
              	if (re <= -4.8e+56) {
              		tmp = sqrt((-4.0 * re)) * 0.5;
              	} else {
              		tmp = sqrt(((im - re) * 2.0)) * 0.5;
              	}
              	return tmp;
              }
              
              real(8) function code(re, im)
                  real(8), intent (in) :: re
                  real(8), intent (in) :: im
                  real(8) :: tmp
                  if (re <= (-4.8d+56)) then
                      tmp = sqrt(((-4.0d0) * re)) * 0.5d0
                  else
                      tmp = sqrt(((im - re) * 2.0d0)) * 0.5d0
                  end if
                  code = tmp
              end function
              
              public static double code(double re, double im) {
              	double tmp;
              	if (re <= -4.8e+56) {
              		tmp = Math.sqrt((-4.0 * re)) * 0.5;
              	} else {
              		tmp = Math.sqrt(((im - re) * 2.0)) * 0.5;
              	}
              	return tmp;
              }
              
              def code(re, im):
              	tmp = 0
              	if re <= -4.8e+56:
              		tmp = math.sqrt((-4.0 * re)) * 0.5
              	else:
              		tmp = math.sqrt(((im - re) * 2.0)) * 0.5
              	return tmp
              
              function code(re, im)
              	tmp = 0.0
              	if (re <= -4.8e+56)
              		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
              	else
              		tmp = Float64(sqrt(Float64(Float64(im - re) * 2.0)) * 0.5);
              	end
              	return tmp
              end
              
              function tmp_2 = code(re, im)
              	tmp = 0.0;
              	if (re <= -4.8e+56)
              		tmp = sqrt((-4.0 * re)) * 0.5;
              	else
              		tmp = sqrt(((im - re) * 2.0)) * 0.5;
              	end
              	tmp_2 = tmp;
              end
              
              code[re_, im_] := If[LessEqual[re, -4.8e+56], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(N[(im - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\
              \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
              
              \mathbf{else}:\\
              \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if re < -4.80000000000000027e56

                1. Initial program 41.4%

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

                  \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
                4. Step-by-step derivation
                  1. lower-*.f6489.0

                    \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
                5. Applied rewrites89.0%

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

                if -4.80000000000000027e56 < re

                1. Initial program 46.0%

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

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

                    \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(im + \color{blue}{\left(\mathsf{neg}\left(re\right)\right)}\right)} \]
                  2. unsub-negN/A

                    \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
                  3. lower--.f6461.8

                    \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
                5. Applied rewrites61.8%

                  \[\leadsto 0.5 \cdot \sqrt{2 \cdot \color{blue}{\left(im - re\right)}} \]
              3. Recombined 2 regimes into one program.
              4. Final simplification67.0%

                \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -4.8 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\ \end{array} \]
              5. Add Preprocessing

              Alternative 7: 63.6% accurate, 1.7× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;re \leq -3.1 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{im \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]
              (FPCore (re im)
               :precision binary64
               (if (<= re -3.1e+56) (* (sqrt (* -4.0 re)) 0.5) (* (sqrt (* im 2.0)) 0.5)))
              double code(double re, double im) {
              	double tmp;
              	if (re <= -3.1e+56) {
              		tmp = sqrt((-4.0 * re)) * 0.5;
              	} else {
              		tmp = sqrt((im * 2.0)) * 0.5;
              	}
              	return tmp;
              }
              
              real(8) function code(re, im)
                  real(8), intent (in) :: re
                  real(8), intent (in) :: im
                  real(8) :: tmp
                  if (re <= (-3.1d+56)) then
                      tmp = sqrt(((-4.0d0) * re)) * 0.5d0
                  else
                      tmp = sqrt((im * 2.0d0)) * 0.5d0
                  end if
                  code = tmp
              end function
              
              public static double code(double re, double im) {
              	double tmp;
              	if (re <= -3.1e+56) {
              		tmp = Math.sqrt((-4.0 * re)) * 0.5;
              	} else {
              		tmp = Math.sqrt((im * 2.0)) * 0.5;
              	}
              	return tmp;
              }
              
              def code(re, im):
              	tmp = 0
              	if re <= -3.1e+56:
              		tmp = math.sqrt((-4.0 * re)) * 0.5
              	else:
              		tmp = math.sqrt((im * 2.0)) * 0.5
              	return tmp
              
              function code(re, im)
              	tmp = 0.0
              	if (re <= -3.1e+56)
              		tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5);
              	else
              		tmp = Float64(sqrt(Float64(im * 2.0)) * 0.5);
              	end
              	return tmp
              end
              
              function tmp_2 = code(re, im)
              	tmp = 0.0;
              	if (re <= -3.1e+56)
              		tmp = sqrt((-4.0 * re)) * 0.5;
              	else
              		tmp = sqrt((im * 2.0)) * 0.5;
              	end
              	tmp_2 = tmp;
              end
              
              code[re_, im_] := If[LessEqual[re, -3.1e+56], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(im * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;re \leq -3.1 \cdot 10^{+56}:\\
              \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
              
              \mathbf{else}:\\
              \;\;\;\;\sqrt{im \cdot 2} \cdot 0.5\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if re < -3.10000000000000005e56

                1. Initial program 41.4%

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

                  \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
                4. Step-by-step derivation
                  1. lower-*.f6489.0

                    \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
                5. Applied rewrites89.0%

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

                if -3.10000000000000005e56 < re

                1. Initial program 46.0%

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

                  \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{2 \cdot im}} \]
                4. Step-by-step derivation
                  1. lower-*.f6461.5

                    \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
                5. Applied rewrites61.5%

                  \[\leadsto 0.5 \cdot \sqrt{\color{blue}{2 \cdot im}} \]
              3. Recombined 2 regimes into one program.
              4. Final simplification66.8%

                \[\leadsto \begin{array}{l} \mathbf{if}\;re \leq -3.1 \cdot 10^{+56}:\\ \;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{im \cdot 2} \cdot 0.5\\ \end{array} \]
              5. Add Preprocessing

              Alternative 8: 25.4% accurate, 2.2× speedup?

              \[\begin{array}{l} \\ \sqrt{-4 \cdot re} \cdot 0.5 \end{array} \]
              (FPCore (re im) :precision binary64 (* (sqrt (* -4.0 re)) 0.5))
              double code(double re, double im) {
              	return sqrt((-4.0 * re)) * 0.5;
              }
              
              real(8) function code(re, im)
                  real(8), intent (in) :: re
                  real(8), intent (in) :: im
                  code = sqrt(((-4.0d0) * re)) * 0.5d0
              end function
              
              public static double code(double re, double im) {
              	return Math.sqrt((-4.0 * re)) * 0.5;
              }
              
              def code(re, im):
              	return math.sqrt((-4.0 * re)) * 0.5
              
              function code(re, im)
              	return Float64(sqrt(Float64(-4.0 * re)) * 0.5)
              end
              
              function tmp = code(re, im)
              	tmp = sqrt((-4.0 * re)) * 0.5;
              end
              
              code[re_, im_] := N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \sqrt{-4 \cdot re} \cdot 0.5
              \end{array}
              
              Derivation
              1. Initial program 45.1%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
              4. Step-by-step derivation
                1. lower-*.f6427.6

                  \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
              5. Applied rewrites27.6%

                \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-4 \cdot re}} \]
              6. Final simplification27.6%

                \[\leadsto \sqrt{-4 \cdot re} \cdot 0.5 \]
              7. Add Preprocessing

              Reproduce

              ?
              herbie shell --seed 2024250 
              (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)))))