math.sqrt on complex, real part

Percentage Accurate: 40.8% → 87.1%
Time: 4.2s
Alternatives: 7
Speedup: 2.6×

Specification

?
\[\begin{array}{l} \\ 0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \end{array} \]
(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)));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(re, im)
use fmin_fmax_functions
    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}

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 7 alternatives:

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

Initial Program: 40.8% 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)));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(re, im)
use fmin_fmax_functions
    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: 87.1% accurate, 0.8× speedup?

\[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -8 \cdot 10^{+112}:\\ \;\;\;\;0.5 \cdot \left(\left(im\_m \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\_m\right) + re\right)}\\ \end{array} \end{array} \]
im_m = (fabs.f64 im)
(FPCore (re im_m)
 :precision binary64
 (if (<= re -8e+112)
   (* 0.5 (* (* im_m (sqrt (* -0.5 (/ 1.0 re)))) (sqrt 2.0)))
   (* 0.5 (sqrt (* 2.0 (+ (hypot re im_m) re))))))
im_m = fabs(im);
double code(double re, double im_m) {
	double tmp;
	if (re <= -8e+112) {
		tmp = 0.5 * ((im_m * sqrt((-0.5 * (1.0 / re)))) * sqrt(2.0));
	} else {
		tmp = 0.5 * sqrt((2.0 * (hypot(re, im_m) + re)));
	}
	return tmp;
}
im_m = Math.abs(im);
public static double code(double re, double im_m) {
	double tmp;
	if (re <= -8e+112) {
		tmp = 0.5 * ((im_m * Math.sqrt((-0.5 * (1.0 / re)))) * Math.sqrt(2.0));
	} else {
		tmp = 0.5 * Math.sqrt((2.0 * (Math.hypot(re, im_m) + re)));
	}
	return tmp;
}
im_m = math.fabs(im)
def code(re, im_m):
	tmp = 0
	if re <= -8e+112:
		tmp = 0.5 * ((im_m * math.sqrt((-0.5 * (1.0 / re)))) * math.sqrt(2.0))
	else:
		tmp = 0.5 * math.sqrt((2.0 * (math.hypot(re, im_m) + re)))
	return tmp
im_m = abs(im)
function code(re, im_m)
	tmp = 0.0
	if (re <= -8e+112)
		tmp = Float64(0.5 * Float64(Float64(im_m * sqrt(Float64(-0.5 * Float64(1.0 / re)))) * sqrt(2.0)));
	else
		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(hypot(re, im_m) + re))));
	end
	return tmp
end
im_m = abs(im);
function tmp_2 = code(re, im_m)
	tmp = 0.0;
	if (re <= -8e+112)
		tmp = 0.5 * ((im_m * sqrt((-0.5 * (1.0 / re)))) * sqrt(2.0));
	else
		tmp = 0.5 * sqrt((2.0 * (hypot(re, im_m) + re)));
	end
	tmp_2 = tmp;
end
im_m = N[Abs[im], $MachinePrecision]
code[re_, im$95$m_] := If[LessEqual[re, -8e+112], N[(0.5 * N[(N[(im$95$m * N[Sqrt[N[(-0.5 * N[(1.0 / re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[re ^ 2 + im$95$m ^ 2], $MachinePrecision] + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
im_m = \left|im\right|

\\
\begin{array}{l}
\mathbf{if}\;re \leq -8 \cdot 10^{+112}:\\
\;\;\;\;0.5 \cdot \left(\left(im\_m \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < -7.9999999999999994e112

    1. Initial program 5.7%

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

      \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{im} + re\right)} \]
    3. Step-by-step derivation
      1. Applied rewrites16.4%

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

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

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

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

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

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

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

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

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\sqrt{im + re}} \cdot \sqrt{2}\right) \]
        9. lower-sqrt.f6416.6

          \[\leadsto 0.5 \cdot \left(\sqrt{im + re} \cdot \color{blue}{\sqrt{2}}\right) \]
      3. Applied rewrites16.6%

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

        \[\leadsto \frac{1}{2} \cdot \left(\sqrt{\color{blue}{im}} \cdot \sqrt{2}\right) \]
      5. Step-by-step derivation
        1. Applied rewrites20.8%

          \[\leadsto 0.5 \cdot \left(\sqrt{\color{blue}{im}} \cdot \sqrt{2}\right) \]
        2. Taylor expanded in re around -inf

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

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

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

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

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

            \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\frac{-1}{2} \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
          6. metadata-evalN/A

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

            \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
          8. metadata-evalN/A

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

            \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\frac{-1}{2} \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
          10. lower-/.f6483.5

            \[\leadsto 0.5 \cdot \left(\left(im \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
        4. Applied rewrites83.5%

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

        if -7.9999999999999994e112 < re

        1. Initial program 47.5%

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

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

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

            \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\sqrt{\color{blue}{re \cdot re + im \cdot im}} + re\right)} \]
          5. lower-hypot.f6487.8

            \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\color{blue}{\mathsf{hypot}\left(re, im\right)} + re\right)} \]
        3. Applied rewrites87.8%

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

      Alternative 2: 76.9% accurate, 0.8× speedup?

      \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -3.3 \cdot 10^{+56}:\\ \;\;\;\;0.5 \cdot \left(\left(im\_m \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right)\\ \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\ \;\;\;\;0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im\_m} + 2, re, im\_m + im\_m\right)}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\ \end{array} \end{array} \]
      im_m = (fabs.f64 im)
      (FPCore (re im_m)
       :precision binary64
       (if (<= re -3.3e+56)
         (* 0.5 (* (* im_m (sqrt (* -0.5 (/ 1.0 re)))) (sqrt 2.0)))
         (if (<= re 8.5e-20)
           (* 0.5 (sqrt (fma (+ (/ re im_m) 2.0) re (+ im_m im_m))))
           (* 0.5 (sqrt (* 4.0 re))))))
      im_m = fabs(im);
      double code(double re, double im_m) {
      	double tmp;
      	if (re <= -3.3e+56) {
      		tmp = 0.5 * ((im_m * sqrt((-0.5 * (1.0 / re)))) * sqrt(2.0));
      	} else if (re <= 8.5e-20) {
      		tmp = 0.5 * sqrt(fma(((re / im_m) + 2.0), re, (im_m + im_m)));
      	} else {
      		tmp = 0.5 * sqrt((4.0 * re));
      	}
      	return tmp;
      }
      
      im_m = abs(im)
      function code(re, im_m)
      	tmp = 0.0
      	if (re <= -3.3e+56)
      		tmp = Float64(0.5 * Float64(Float64(im_m * sqrt(Float64(-0.5 * Float64(1.0 / re)))) * sqrt(2.0)));
      	elseif (re <= 8.5e-20)
      		tmp = Float64(0.5 * sqrt(fma(Float64(Float64(re / im_m) + 2.0), re, Float64(im_m + im_m))));
      	else
      		tmp = Float64(0.5 * sqrt(Float64(4.0 * re)));
      	end
      	return tmp
      end
      
      im_m = N[Abs[im], $MachinePrecision]
      code[re_, im$95$m_] := If[LessEqual[re, -3.3e+56], N[(0.5 * N[(N[(im$95$m * N[Sqrt[N[(-0.5 * N[(1.0 / re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 8.5e-20], N[(0.5 * N[Sqrt[N[(N[(N[(re / im$95$m), $MachinePrecision] + 2.0), $MachinePrecision] * re + N[(im$95$m + im$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(4.0 * re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      im_m = \left|im\right|
      
      \\
      \begin{array}{l}
      \mathbf{if}\;re \leq -3.3 \cdot 10^{+56}:\\
      \;\;\;\;0.5 \cdot \left(\left(im\_m \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right)\\
      
      \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\
      \;\;\;\;0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im\_m} + 2, re, im\_m + im\_m\right)}\\
      
      \mathbf{else}:\\
      \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if re < -3.30000000000000002e56

        1. Initial program 9.1%

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

          \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{im} + re\right)} \]
        3. Step-by-step derivation
          1. Applied rewrites22.0%

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

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

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

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

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

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

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

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

              \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\sqrt{im + re}} \cdot \sqrt{2}\right) \]
            9. lower-sqrt.f6422.0

              \[\leadsto 0.5 \cdot \left(\sqrt{im + re} \cdot \color{blue}{\sqrt{2}}\right) \]
          3. Applied rewrites22.0%

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

            \[\leadsto \frac{1}{2} \cdot \left(\sqrt{\color{blue}{im}} \cdot \sqrt{2}\right) \]
          5. Step-by-step derivation
            1. Applied rewrites26.0%

              \[\leadsto 0.5 \cdot \left(\sqrt{\color{blue}{im}} \cdot \sqrt{2}\right) \]
            2. Taylor expanded in re around -inf

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

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

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

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

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

                \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\frac{-1}{2} \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
              6. metadata-evalN/A

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

                \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
              8. metadata-evalN/A

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

                \[\leadsto \frac{1}{2} \cdot \left(\left(im \cdot \sqrt{\frac{-1}{2} \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
              10. lower-/.f6478.4

                \[\leadsto 0.5 \cdot \left(\left(im \cdot \sqrt{-0.5 \cdot \frac{1}{re}}\right) \cdot \sqrt{2}\right) \]
            4. Applied rewrites78.4%

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

            if -3.30000000000000002e56 < re < 8.5000000000000005e-20

            1. Initial program 52.7%

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

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

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

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

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

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

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, 2 \cdot im\right)} \]
              7. count-2-revN/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, im + im\right)} \]
              8. lower-+.f6476.3

                \[\leadsto 0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, im + im\right)} \]
            4. Applied rewrites76.3%

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

            if 8.5000000000000005e-20 < re

            1. Initial program 42.0%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{4 \cdot re}} \]
            3. Step-by-step derivation
              1. lower-*.f6476.8

                \[\leadsto 0.5 \cdot \sqrt{4 \cdot \color{blue}{re}} \]
            4. Applied rewrites76.8%

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{4 \cdot re}} \]
          6. Recombined 3 regimes into one program.
          7. Add Preprocessing

          Alternative 3: 72.4% accurate, 0.8× speedup?

          \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -3.6 \cdot 10^{+113}:\\ \;\;\;\;0.5 \cdot \sqrt{-im\_m \cdot \frac{im\_m}{re}}\\ \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\ \;\;\;\;0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im\_m} + 2, re, im\_m + im\_m\right)}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\ \end{array} \end{array} \]
          im_m = (fabs.f64 im)
          (FPCore (re im_m)
           :precision binary64
           (if (<= re -3.6e+113)
             (* 0.5 (sqrt (- (* im_m (/ im_m re)))))
             (if (<= re 8.5e-20)
               (* 0.5 (sqrt (fma (+ (/ re im_m) 2.0) re (+ im_m im_m))))
               (* 0.5 (sqrt (* 4.0 re))))))
          im_m = fabs(im);
          double code(double re, double im_m) {
          	double tmp;
          	if (re <= -3.6e+113) {
          		tmp = 0.5 * sqrt(-(im_m * (im_m / re)));
          	} else if (re <= 8.5e-20) {
          		tmp = 0.5 * sqrt(fma(((re / im_m) + 2.0), re, (im_m + im_m)));
          	} else {
          		tmp = 0.5 * sqrt((4.0 * re));
          	}
          	return tmp;
          }
          
          im_m = abs(im)
          function code(re, im_m)
          	tmp = 0.0
          	if (re <= -3.6e+113)
          		tmp = Float64(0.5 * sqrt(Float64(-Float64(im_m * Float64(im_m / re)))));
          	elseif (re <= 8.5e-20)
          		tmp = Float64(0.5 * sqrt(fma(Float64(Float64(re / im_m) + 2.0), re, Float64(im_m + im_m))));
          	else
          		tmp = Float64(0.5 * sqrt(Float64(4.0 * re)));
          	end
          	return tmp
          end
          
          im_m = N[Abs[im], $MachinePrecision]
          code[re_, im$95$m_] := If[LessEqual[re, -3.6e+113], N[(0.5 * N[Sqrt[(-N[(im$95$m * N[(im$95$m / re), $MachinePrecision]), $MachinePrecision])], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 8.5e-20], N[(0.5 * N[Sqrt[N[(N[(N[(re / im$95$m), $MachinePrecision] + 2.0), $MachinePrecision] * re + N[(im$95$m + im$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(4.0 * re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
          
          \begin{array}{l}
          im_m = \left|im\right|
          
          \\
          \begin{array}{l}
          \mathbf{if}\;re \leq -3.6 \cdot 10^{+113}:\\
          \;\;\;\;0.5 \cdot \sqrt{-im\_m \cdot \frac{im\_m}{re}}\\
          
          \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\
          \;\;\;\;0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im\_m} + 2, re, im\_m + im\_m\right)}\\
          
          \mathbf{else}:\\
          \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if re < -3.59999999999999992e113

            1. Initial program 5.6%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-1 \cdot \frac{{im}^{2}}{re}}} \]
            3. Step-by-step derivation
              1. mul-1-negN/A

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{{im}^{2}}{re}} \]
              3. lower-/.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{{im}^{2}}{re}} \]
              4. pow2N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              5. lift-*.f6451.4

                \[\leadsto 0.5 \cdot \sqrt{-\frac{im \cdot im}{re}} \]
            4. Applied rewrites51.4%

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-\frac{im \cdot im}{re}}} \]
            5. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              2. lift-/.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              3. associate-/l*N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-im \cdot \frac{im}{re}} \]
              4. lower-*.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-im \cdot \frac{im}{re}} \]
              5. lower-/.f6461.5

                \[\leadsto 0.5 \cdot \sqrt{-im \cdot \frac{im}{re}} \]
            6. Applied rewrites61.5%

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

            if -3.59999999999999992e113 < re < 8.5000000000000005e-20

            1. Initial program 50.0%

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

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

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

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

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

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

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, 2 \cdot im\right)} \]
              7. count-2-revN/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, im + im\right)} \]
              8. lower-+.f6473.5

                \[\leadsto 0.5 \cdot \sqrt{\mathsf{fma}\left(\frac{re}{im} + 2, re, im + im\right)} \]
            4. Applied rewrites73.5%

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

            if 8.5000000000000005e-20 < re

            1. Initial program 42.0%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{4 \cdot re}} \]
            3. Step-by-step derivation
              1. lower-*.f6476.8

                \[\leadsto 0.5 \cdot \sqrt{4 \cdot \color{blue}{re}} \]
            4. Applied rewrites76.8%

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{4 \cdot re}} \]
          3. Recombined 3 regimes into one program.
          4. Add Preprocessing

          Alternative 4: 72.3% accurate, 1.1× speedup?

          \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -3.1 \cdot 10^{+113}:\\ \;\;\;\;0.5 \cdot \sqrt{-im\_m \cdot \frac{im\_m}{re}}\\ \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im\_m + re\right)}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\ \end{array} \end{array} \]
          im_m = (fabs.f64 im)
          (FPCore (re im_m)
           :precision binary64
           (if (<= re -3.1e+113)
             (* 0.5 (sqrt (- (* im_m (/ im_m re)))))
             (if (<= re 8.5e-20)
               (* 0.5 (sqrt (* 2.0 (+ im_m re))))
               (* 0.5 (sqrt (* 4.0 re))))))
          im_m = fabs(im);
          double code(double re, double im_m) {
          	double tmp;
          	if (re <= -3.1e+113) {
          		tmp = 0.5 * sqrt(-(im_m * (im_m / re)));
          	} else if (re <= 8.5e-20) {
          		tmp = 0.5 * sqrt((2.0 * (im_m + re)));
          	} else {
          		tmp = 0.5 * sqrt((4.0 * re));
          	}
          	return tmp;
          }
          
          im_m =     private
          module fmin_fmax_functions
              implicit none
              private
              public fmax
              public fmin
          
              interface fmax
                  module procedure fmax88
                  module procedure fmax44
                  module procedure fmax84
                  module procedure fmax48
              end interface
              interface fmin
                  module procedure fmin88
                  module procedure fmin44
                  module procedure fmin84
                  module procedure fmin48
              end interface
          contains
              real(8) function fmax88(x, y) result (res)
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  res = merge(y, merge(x, max(x, y), y /= y), x /= x)
              end function
              real(4) function fmax44(x, y) result (res)
                  real(4), intent (in) :: x
                  real(4), intent (in) :: y
                  res = merge(y, merge(x, max(x, y), y /= y), x /= x)
              end function
              real(8) function fmax84(x, y) result(res)
                  real(8), intent (in) :: x
                  real(4), intent (in) :: y
                  res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
              end function
              real(8) function fmax48(x, y) result(res)
                  real(4), intent (in) :: x
                  real(8), intent (in) :: y
                  res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
              end function
              real(8) function fmin88(x, y) result (res)
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  res = merge(y, merge(x, min(x, y), y /= y), x /= x)
              end function
              real(4) function fmin44(x, y) result (res)
                  real(4), intent (in) :: x
                  real(4), intent (in) :: y
                  res = merge(y, merge(x, min(x, y), y /= y), x /= x)
              end function
              real(8) function fmin84(x, y) result(res)
                  real(8), intent (in) :: x
                  real(4), intent (in) :: y
                  res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
              end function
              real(8) function fmin48(x, y) result(res)
                  real(4), intent (in) :: x
                  real(8), intent (in) :: y
                  res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
              end function
          end module
          
          real(8) function code(re, im_m)
          use fmin_fmax_functions
              real(8), intent (in) :: re
              real(8), intent (in) :: im_m
              real(8) :: tmp
              if (re <= (-3.1d+113)) then
                  tmp = 0.5d0 * sqrt(-(im_m * (im_m / re)))
              else if (re <= 8.5d-20) then
                  tmp = 0.5d0 * sqrt((2.0d0 * (im_m + re)))
              else
                  tmp = 0.5d0 * sqrt((4.0d0 * re))
              end if
              code = tmp
          end function
          
          im_m = Math.abs(im);
          public static double code(double re, double im_m) {
          	double tmp;
          	if (re <= -3.1e+113) {
          		tmp = 0.5 * Math.sqrt(-(im_m * (im_m / re)));
          	} else if (re <= 8.5e-20) {
          		tmp = 0.5 * Math.sqrt((2.0 * (im_m + re)));
          	} else {
          		tmp = 0.5 * Math.sqrt((4.0 * re));
          	}
          	return tmp;
          }
          
          im_m = math.fabs(im)
          def code(re, im_m):
          	tmp = 0
          	if re <= -3.1e+113:
          		tmp = 0.5 * math.sqrt(-(im_m * (im_m / re)))
          	elif re <= 8.5e-20:
          		tmp = 0.5 * math.sqrt((2.0 * (im_m + re)))
          	else:
          		tmp = 0.5 * math.sqrt((4.0 * re))
          	return tmp
          
          im_m = abs(im)
          function code(re, im_m)
          	tmp = 0.0
          	if (re <= -3.1e+113)
          		tmp = Float64(0.5 * sqrt(Float64(-Float64(im_m * Float64(im_m / re)))));
          	elseif (re <= 8.5e-20)
          		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(im_m + re))));
          	else
          		tmp = Float64(0.5 * sqrt(Float64(4.0 * re)));
          	end
          	return tmp
          end
          
          im_m = abs(im);
          function tmp_2 = code(re, im_m)
          	tmp = 0.0;
          	if (re <= -3.1e+113)
          		tmp = 0.5 * sqrt(-(im_m * (im_m / re)));
          	elseif (re <= 8.5e-20)
          		tmp = 0.5 * sqrt((2.0 * (im_m + re)));
          	else
          		tmp = 0.5 * sqrt((4.0 * re));
          	end
          	tmp_2 = tmp;
          end
          
          im_m = N[Abs[im], $MachinePrecision]
          code[re_, im$95$m_] := If[LessEqual[re, -3.1e+113], N[(0.5 * N[Sqrt[(-N[(im$95$m * N[(im$95$m / re), $MachinePrecision]), $MachinePrecision])], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 8.5e-20], N[(0.5 * N[Sqrt[N[(2.0 * N[(im$95$m + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(4.0 * re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
          
          \begin{array}{l}
          im_m = \left|im\right|
          
          \\
          \begin{array}{l}
          \mathbf{if}\;re \leq -3.1 \cdot 10^{+113}:\\
          \;\;\;\;0.5 \cdot \sqrt{-im\_m \cdot \frac{im\_m}{re}}\\
          
          \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\
          \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im\_m + re\right)}\\
          
          \mathbf{else}:\\
          \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if re < -3.09999999999999991e113

            1. Initial program 5.6%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{-1 \cdot \frac{{im}^{2}}{re}}} \]
            3. Step-by-step derivation
              1. mul-1-negN/A

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{{im}^{2}}{re}} \]
              3. lower-/.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{{im}^{2}}{re}} \]
              4. pow2N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              5. lift-*.f6451.4

                \[\leadsto 0.5 \cdot \sqrt{-\frac{im \cdot im}{re}} \]
            4. Applied rewrites51.4%

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{-\frac{im \cdot im}{re}}} \]
            5. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              2. lift-/.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-\frac{im \cdot im}{re}} \]
              3. associate-/l*N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-im \cdot \frac{im}{re}} \]
              4. lower-*.f64N/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{-im \cdot \frac{im}{re}} \]
              5. lower-/.f6461.5

                \[\leadsto 0.5 \cdot \sqrt{-im \cdot \frac{im}{re}} \]
            6. Applied rewrites61.5%

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

            if -3.09999999999999991e113 < re < 8.5000000000000005e-20

            1. Initial program 50.0%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\color{blue}{im} + re\right)} \]
            3. Step-by-step derivation
              1. Applied rewrites73.3%

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

              if 8.5000000000000005e-20 < re

              1. Initial program 42.0%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{4 \cdot re}} \]
              3. Step-by-step derivation
                1. lower-*.f6476.8

                  \[\leadsto 0.5 \cdot \sqrt{4 \cdot \color{blue}{re}} \]
              4. Applied rewrites76.8%

                \[\leadsto 0.5 \cdot \sqrt{\color{blue}{4 \cdot re}} \]
            4. Recombined 3 regimes into one program.
            5. Add Preprocessing

            Alternative 5: 66.5% accurate, 1.3× speedup?

            \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -1.45 \cdot 10^{+210}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\left(-re\right) + re\right)}\\ \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\ \;\;\;\;0.5 \cdot \sqrt{im\_m + im\_m}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\ \end{array} \end{array} \]
            im_m = (fabs.f64 im)
            (FPCore (re im_m)
             :precision binary64
             (if (<= re -1.45e+210)
               (* 0.5 (sqrt (* 2.0 (+ (- re) re))))
               (if (<= re 8.5e-20)
                 (* 0.5 (sqrt (+ im_m im_m)))
                 (* 0.5 (sqrt (* 4.0 re))))))
            im_m = fabs(im);
            double code(double re, double im_m) {
            	double tmp;
            	if (re <= -1.45e+210) {
            		tmp = 0.5 * sqrt((2.0 * (-re + re)));
            	} else if (re <= 8.5e-20) {
            		tmp = 0.5 * sqrt((im_m + im_m));
            	} else {
            		tmp = 0.5 * sqrt((4.0 * re));
            	}
            	return tmp;
            }
            
            im_m =     private
            module fmin_fmax_functions
                implicit none
                private
                public fmax
                public fmin
            
                interface fmax
                    module procedure fmax88
                    module procedure fmax44
                    module procedure fmax84
                    module procedure fmax48
                end interface
                interface fmin
                    module procedure fmin88
                    module procedure fmin44
                    module procedure fmin84
                    module procedure fmin48
                end interface
            contains
                real(8) function fmax88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(4) function fmax44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(8) function fmax84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmax48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                end function
                real(8) function fmin88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(4) function fmin44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(8) function fmin84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmin48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                end function
            end module
            
            real(8) function code(re, im_m)
            use fmin_fmax_functions
                real(8), intent (in) :: re
                real(8), intent (in) :: im_m
                real(8) :: tmp
                if (re <= (-1.45d+210)) then
                    tmp = 0.5d0 * sqrt((2.0d0 * (-re + re)))
                else if (re <= 8.5d-20) then
                    tmp = 0.5d0 * sqrt((im_m + im_m))
                else
                    tmp = 0.5d0 * sqrt((4.0d0 * re))
                end if
                code = tmp
            end function
            
            im_m = Math.abs(im);
            public static double code(double re, double im_m) {
            	double tmp;
            	if (re <= -1.45e+210) {
            		tmp = 0.5 * Math.sqrt((2.0 * (-re + re)));
            	} else if (re <= 8.5e-20) {
            		tmp = 0.5 * Math.sqrt((im_m + im_m));
            	} else {
            		tmp = 0.5 * Math.sqrt((4.0 * re));
            	}
            	return tmp;
            }
            
            im_m = math.fabs(im)
            def code(re, im_m):
            	tmp = 0
            	if re <= -1.45e+210:
            		tmp = 0.5 * math.sqrt((2.0 * (-re + re)))
            	elif re <= 8.5e-20:
            		tmp = 0.5 * math.sqrt((im_m + im_m))
            	else:
            		tmp = 0.5 * math.sqrt((4.0 * re))
            	return tmp
            
            im_m = abs(im)
            function code(re, im_m)
            	tmp = 0.0
            	if (re <= -1.45e+210)
            		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(Float64(-re) + re))));
            	elseif (re <= 8.5e-20)
            		tmp = Float64(0.5 * sqrt(Float64(im_m + im_m)));
            	else
            		tmp = Float64(0.5 * sqrt(Float64(4.0 * re)));
            	end
            	return tmp
            end
            
            im_m = abs(im);
            function tmp_2 = code(re, im_m)
            	tmp = 0.0;
            	if (re <= -1.45e+210)
            		tmp = 0.5 * sqrt((2.0 * (-re + re)));
            	elseif (re <= 8.5e-20)
            		tmp = 0.5 * sqrt((im_m + im_m));
            	else
            		tmp = 0.5 * sqrt((4.0 * re));
            	end
            	tmp_2 = tmp;
            end
            
            im_m = N[Abs[im], $MachinePrecision]
            code[re_, im$95$m_] := If[LessEqual[re, -1.45e+210], N[(0.5 * N[Sqrt[N[(2.0 * N[((-re) + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 8.5e-20], N[(0.5 * N[Sqrt[N[(im$95$m + im$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(4.0 * re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
            
            \begin{array}{l}
            im_m = \left|im\right|
            
            \\
            \begin{array}{l}
            \mathbf{if}\;re \leq -1.45 \cdot 10^{+210}:\\
            \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\left(-re\right) + re\right)}\\
            
            \mathbf{elif}\;re \leq 8.5 \cdot 10^{-20}:\\
            \;\;\;\;0.5 \cdot \sqrt{im\_m + im\_m}\\
            
            \mathbf{else}:\\
            \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if re < -1.44999999999999996e210

              1. Initial program 2.6%

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

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

                  \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \left(\left(\mathsf{neg}\left(re\right)\right) + re\right)} \]
                2. lower-neg.f6421.8

                  \[\leadsto 0.5 \cdot \sqrt{2 \cdot \left(\left(-re\right) + re\right)} \]
              4. Applied rewrites21.8%

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

              if -1.44999999999999996e210 < re < 8.5000000000000005e-20

              1. Initial program 45.2%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{2 \cdot im}} \]
              3. Step-by-step derivation
                1. count-2-revN/A

                  \[\leadsto \frac{1}{2} \cdot \sqrt{im + \color{blue}{im}} \]
                2. lower-+.f6468.1

                  \[\leadsto 0.5 \cdot \sqrt{im + \color{blue}{im}} \]
              4. Applied rewrites68.1%

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

              if 8.5000000000000005e-20 < re

              1. Initial program 42.0%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{4 \cdot re}} \]
              3. Step-by-step derivation
                1. lower-*.f6476.8

                  \[\leadsto 0.5 \cdot \sqrt{4 \cdot \color{blue}{re}} \]
              4. Applied rewrites76.8%

                \[\leadsto 0.5 \cdot \sqrt{\color{blue}{4 \cdot re}} \]
            3. Recombined 3 regimes into one program.
            4. Add Preprocessing

            Alternative 6: 65.8% accurate, 1.7× speedup?

            \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq 8.5 \cdot 10^{-20}:\\ \;\;\;\;0.5 \cdot \sqrt{im\_m + im\_m}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\ \end{array} \end{array} \]
            im_m = (fabs.f64 im)
            (FPCore (re im_m)
             :precision binary64
             (if (<= re 8.5e-20) (* 0.5 (sqrt (+ im_m im_m))) (* 0.5 (sqrt (* 4.0 re)))))
            im_m = fabs(im);
            double code(double re, double im_m) {
            	double tmp;
            	if (re <= 8.5e-20) {
            		tmp = 0.5 * sqrt((im_m + im_m));
            	} else {
            		tmp = 0.5 * sqrt((4.0 * re));
            	}
            	return tmp;
            }
            
            im_m =     private
            module fmin_fmax_functions
                implicit none
                private
                public fmax
                public fmin
            
                interface fmax
                    module procedure fmax88
                    module procedure fmax44
                    module procedure fmax84
                    module procedure fmax48
                end interface
                interface fmin
                    module procedure fmin88
                    module procedure fmin44
                    module procedure fmin84
                    module procedure fmin48
                end interface
            contains
                real(8) function fmax88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(4) function fmax44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(8) function fmax84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmax48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                end function
                real(8) function fmin88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(4) function fmin44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(8) function fmin84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmin48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                end function
            end module
            
            real(8) function code(re, im_m)
            use fmin_fmax_functions
                real(8), intent (in) :: re
                real(8), intent (in) :: im_m
                real(8) :: tmp
                if (re <= 8.5d-20) then
                    tmp = 0.5d0 * sqrt((im_m + im_m))
                else
                    tmp = 0.5d0 * sqrt((4.0d0 * re))
                end if
                code = tmp
            end function
            
            im_m = Math.abs(im);
            public static double code(double re, double im_m) {
            	double tmp;
            	if (re <= 8.5e-20) {
            		tmp = 0.5 * Math.sqrt((im_m + im_m));
            	} else {
            		tmp = 0.5 * Math.sqrt((4.0 * re));
            	}
            	return tmp;
            }
            
            im_m = math.fabs(im)
            def code(re, im_m):
            	tmp = 0
            	if re <= 8.5e-20:
            		tmp = 0.5 * math.sqrt((im_m + im_m))
            	else:
            		tmp = 0.5 * math.sqrt((4.0 * re))
            	return tmp
            
            im_m = abs(im)
            function code(re, im_m)
            	tmp = 0.0
            	if (re <= 8.5e-20)
            		tmp = Float64(0.5 * sqrt(Float64(im_m + im_m)));
            	else
            		tmp = Float64(0.5 * sqrt(Float64(4.0 * re)));
            	end
            	return tmp
            end
            
            im_m = abs(im);
            function tmp_2 = code(re, im_m)
            	tmp = 0.0;
            	if (re <= 8.5e-20)
            		tmp = 0.5 * sqrt((im_m + im_m));
            	else
            		tmp = 0.5 * sqrt((4.0 * re));
            	end
            	tmp_2 = tmp;
            end
            
            im_m = N[Abs[im], $MachinePrecision]
            code[re_, im$95$m_] := If[LessEqual[re, 8.5e-20], N[(0.5 * N[Sqrt[N[(im$95$m + im$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(4.0 * re), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            im_m = \left|im\right|
            
            \\
            \begin{array}{l}
            \mathbf{if}\;re \leq 8.5 \cdot 10^{-20}:\\
            \;\;\;\;0.5 \cdot \sqrt{im\_m + im\_m}\\
            
            \mathbf{else}:\\
            \;\;\;\;0.5 \cdot \sqrt{4 \cdot re}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if re < 8.5000000000000005e-20

              1. Initial program 40.4%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{2 \cdot im}} \]
              3. Step-by-step derivation
                1. count-2-revN/A

                  \[\leadsto \frac{1}{2} \cdot \sqrt{im + \color{blue}{im}} \]
                2. lower-+.f6461.8

                  \[\leadsto 0.5 \cdot \sqrt{im + \color{blue}{im}} \]
              4. Applied rewrites61.8%

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

              if 8.5000000000000005e-20 < re

              1. Initial program 42.0%

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

                \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{4 \cdot re}} \]
              3. Step-by-step derivation
                1. lower-*.f6476.8

                  \[\leadsto 0.5 \cdot \sqrt{4 \cdot \color{blue}{re}} \]
              4. Applied rewrites76.8%

                \[\leadsto 0.5 \cdot \sqrt{\color{blue}{4 \cdot re}} \]
            3. Recombined 2 regimes into one program.
            4. Add Preprocessing

            Alternative 7: 52.9% accurate, 2.6× speedup?

            \[\begin{array}{l} im_m = \left|im\right| \\ 0.5 \cdot \sqrt{im\_m + im\_m} \end{array} \]
            im_m = (fabs.f64 im)
            (FPCore (re im_m) :precision binary64 (* 0.5 (sqrt (+ im_m im_m))))
            im_m = fabs(im);
            double code(double re, double im_m) {
            	return 0.5 * sqrt((im_m + im_m));
            }
            
            im_m =     private
            module fmin_fmax_functions
                implicit none
                private
                public fmax
                public fmin
            
                interface fmax
                    module procedure fmax88
                    module procedure fmax44
                    module procedure fmax84
                    module procedure fmax48
                end interface
                interface fmin
                    module procedure fmin88
                    module procedure fmin44
                    module procedure fmin84
                    module procedure fmin48
                end interface
            contains
                real(8) function fmax88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(4) function fmax44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(8) function fmax84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmax48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                end function
                real(8) function fmin88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(4) function fmin44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(8) function fmin84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmin48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                end function
            end module
            
            real(8) function code(re, im_m)
            use fmin_fmax_functions
                real(8), intent (in) :: re
                real(8), intent (in) :: im_m
                code = 0.5d0 * sqrt((im_m + im_m))
            end function
            
            im_m = Math.abs(im);
            public static double code(double re, double im_m) {
            	return 0.5 * Math.sqrt((im_m + im_m));
            }
            
            im_m = math.fabs(im)
            def code(re, im_m):
            	return 0.5 * math.sqrt((im_m + im_m))
            
            im_m = abs(im)
            function code(re, im_m)
            	return Float64(0.5 * sqrt(Float64(im_m + im_m)))
            end
            
            im_m = abs(im);
            function tmp = code(re, im_m)
            	tmp = 0.5 * sqrt((im_m + im_m));
            end
            
            im_m = N[Abs[im], $MachinePrecision]
            code[re_, im$95$m_] := N[(0.5 * N[Sqrt[N[(im$95$m + im$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            im_m = \left|im\right|
            
            \\
            0.5 \cdot \sqrt{im\_m + im\_m}
            \end{array}
            
            Derivation
            1. Initial program 40.8%

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

              \[\leadsto \frac{1}{2} \cdot \sqrt{\color{blue}{2 \cdot im}} \]
            3. Step-by-step derivation
              1. count-2-revN/A

                \[\leadsto \frac{1}{2} \cdot \sqrt{im + \color{blue}{im}} \]
              2. lower-+.f6452.9

                \[\leadsto 0.5 \cdot \sqrt{im + \color{blue}{im}} \]
            4. Applied rewrites52.9%

              \[\leadsto 0.5 \cdot \sqrt{\color{blue}{im + im}} \]
            5. Add Preprocessing

            Developer Target 1: 47.6% accurate, 0.6× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{re \cdot re + im \cdot im}\\ \mathbf{if}\;re < 0:\\ \;\;\;\;0.5 \cdot \left(\sqrt{2} \cdot \sqrt{\frac{im \cdot im}{t\_0 - re}}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(t\_0 + re\right)}\\ \end{array} \end{array} \]
            (FPCore (re im)
             :precision binary64
             (let* ((t_0 (sqrt (+ (* re re) (* im im)))))
               (if (< re 0.0)
                 (* 0.5 (* (sqrt 2.0) (sqrt (/ (* im im) (- t_0 re)))))
                 (* 0.5 (sqrt (* 2.0 (+ t_0 re)))))))
            double code(double re, double im) {
            	double t_0 = sqrt(((re * re) + (im * im)));
            	double tmp;
            	if (re < 0.0) {
            		tmp = 0.5 * (sqrt(2.0) * sqrt(((im * im) / (t_0 - re))));
            	} else {
            		tmp = 0.5 * sqrt((2.0 * (t_0 + re)));
            	}
            	return tmp;
            }
            
            module fmin_fmax_functions
                implicit none
                private
                public fmax
                public fmin
            
                interface fmax
                    module procedure fmax88
                    module procedure fmax44
                    module procedure fmax84
                    module procedure fmax48
                end interface
                interface fmin
                    module procedure fmin88
                    module procedure fmin44
                    module procedure fmin84
                    module procedure fmin48
                end interface
            contains
                real(8) function fmax88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(4) function fmax44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(8) function fmax84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmax48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                end function
                real(8) function fmin88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(4) function fmin44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(8) function fmin84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmin48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                end function
            end module
            
            real(8) function code(re, im)
            use fmin_fmax_functions
                real(8), intent (in) :: re
                real(8), intent (in) :: im
                real(8) :: t_0
                real(8) :: tmp
                t_0 = sqrt(((re * re) + (im * im)))
                if (re < 0.0d0) then
                    tmp = 0.5d0 * (sqrt(2.0d0) * sqrt(((im * im) / (t_0 - re))))
                else
                    tmp = 0.5d0 * sqrt((2.0d0 * (t_0 + re)))
                end if
                code = tmp
            end function
            
            public static double code(double re, double im) {
            	double t_0 = Math.sqrt(((re * re) + (im * im)));
            	double tmp;
            	if (re < 0.0) {
            		tmp = 0.5 * (Math.sqrt(2.0) * Math.sqrt(((im * im) / (t_0 - re))));
            	} else {
            		tmp = 0.5 * Math.sqrt((2.0 * (t_0 + re)));
            	}
            	return tmp;
            }
            
            def code(re, im):
            	t_0 = math.sqrt(((re * re) + (im * im)))
            	tmp = 0
            	if re < 0.0:
            		tmp = 0.5 * (math.sqrt(2.0) * math.sqrt(((im * im) / (t_0 - re))))
            	else:
            		tmp = 0.5 * math.sqrt((2.0 * (t_0 + re)))
            	return tmp
            
            function code(re, im)
            	t_0 = sqrt(Float64(Float64(re * re) + Float64(im * im)))
            	tmp = 0.0
            	if (re < 0.0)
            		tmp = Float64(0.5 * Float64(sqrt(2.0) * sqrt(Float64(Float64(im * im) / Float64(t_0 - re)))));
            	else
            		tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(t_0 + re))));
            	end
            	return tmp
            end
            
            function tmp_2 = code(re, im)
            	t_0 = sqrt(((re * re) + (im * im)));
            	tmp = 0.0;
            	if (re < 0.0)
            		tmp = 0.5 * (sqrt(2.0) * sqrt(((im * im) / (t_0 - re))));
            	else
            		tmp = 0.5 * sqrt((2.0 * (t_0 + re)));
            	end
            	tmp_2 = tmp;
            end
            
            code[re_, im_] := Block[{t$95$0 = N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[Less[re, 0.0], N[(0.5 * N[(N[Sqrt[2.0], $MachinePrecision] * N[Sqrt[N[(N[(im * im), $MachinePrecision] / N[(t$95$0 - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(2.0 * N[(t$95$0 + re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            t_0 := \sqrt{re \cdot re + im \cdot im}\\
            \mathbf{if}\;re < 0:\\
            \;\;\;\;0.5 \cdot \left(\sqrt{2} \cdot \sqrt{\frac{im \cdot im}{t\_0 - re}}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(t\_0 + re\right)}\\
            
            
            \end{array}
            \end{array}
            

            Reproduce

            ?
            herbie shell --seed 2025112 
            (FPCore (re im)
              :name "math.sqrt on complex, real part"
              :precision binary64
            
              :alt
              (! :herbie-platform c (if (< re 0) (* 1/2 (* (sqrt 2) (sqrt (/ (* im im) (- (modulus re im) re))))) (* 1/2 (sqrt (* 2 (+ (modulus re im) re))))))
            
              (* 0.5 (sqrt (* 2.0 (+ (sqrt (+ (* re re) (* im im))) re)))))