math.sqrt on complex, real part

Percentage Accurate: 41.8% → 88.9%
Time: 4.3s
Alternatives: 6
Speedup: 1.5×

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 6 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: 41.8% 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: 88.9% accurate, 0.5× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;2 \cdot \left(\sqrt{re \cdot re + im\_m \cdot im\_m} + re\right) \leq 0:\\
\;\;\;\;0.5 \cdot e^{\mathsf{fma}\left(2, \log im\_m, \log \left(\frac{-1}{re}\right)\right) \cdot 0.5}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 #s(literal 2 binary64) (+.f64 (sqrt.f64 (+.f64 (*.f64 re re) (*.f64 im im))) re)) < 0.0

    1. Initial program 7.7%

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

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

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

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

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

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

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

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{{\left(2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)\right)}^{\frac{1}{2}}} \]
      9. pow-to-expN/A

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

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

        \[\leadsto \frac{1}{2} \cdot e^{\color{blue}{\log \left(2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)\right) \cdot \frac{1}{2}}} \]
    3. Applied rewrites17.9%

      \[\leadsto 0.5 \cdot \color{blue}{e^{\log \left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right) \cdot 0.5}} \]
    4. Taylor expanded in re around -inf

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

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

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

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

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

        \[\leadsto \frac{1}{2} \cdot e^{\mathsf{fma}\left(2, \log im, \log \left(\frac{-1}{re}\right)\right) \cdot \frac{1}{2}} \]
      6. lower-/.f6482.1

        \[\leadsto 0.5 \cdot e^{\mathsf{fma}\left(2, \log im, \log \left(\frac{-1}{re}\right)\right) \cdot 0.5} \]
    6. Applied rewrites82.1%

      \[\leadsto 0.5 \cdot e^{\color{blue}{\mathsf{fma}\left(2, \log im, \log \left(\frac{-1}{re}\right)\right)} \cdot 0.5} \]

    if 0.0 < (*.f64 #s(literal 2 binary64) (+.f64 (sqrt.f64 (+.f64 (*.f64 re re) (*.f64 im im))) re))

    1. Initial program 47.8%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]
    3. Applied rewrites90.1%

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

Alternative 2: 83.0% accurate, 0.9× speedup?

\[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -1.7 \cdot 10^{+157}:\\ \;\;\;\;0.5 \cdot e^{\log \left(-im\_m \cdot \frac{im\_m}{re}\right) \cdot 0.5}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im\_m, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]
im_m = (fabs.f64 im)
(FPCore (re im_m)
 :precision binary64
 (if (<= re -1.7e+157)
   (* 0.5 (exp (* (log (- (* im_m (/ im_m re)))) 0.5)))
   (* (sqrt (* (+ (hypot im_m re) re) 2.0)) 0.5)))
im_m = fabs(im);
double code(double re, double im_m) {
	double tmp;
	if (re <= -1.7e+157) {
		tmp = 0.5 * exp((log(-(im_m * (im_m / re))) * 0.5));
	} else {
		tmp = sqrt(((hypot(im_m, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}
im_m = Math.abs(im);
public static double code(double re, double im_m) {
	double tmp;
	if (re <= -1.7e+157) {
		tmp = 0.5 * Math.exp((Math.log(-(im_m * (im_m / re))) * 0.5));
	} else {
		tmp = Math.sqrt(((Math.hypot(im_m, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}
im_m = math.fabs(im)
def code(re, im_m):
	tmp = 0
	if re <= -1.7e+157:
		tmp = 0.5 * math.exp((math.log(-(im_m * (im_m / re))) * 0.5))
	else:
		tmp = math.sqrt(((math.hypot(im_m, re) + re) * 2.0)) * 0.5
	return tmp
im_m = abs(im)
function code(re, im_m)
	tmp = 0.0
	if (re <= -1.7e+157)
		tmp = Float64(0.5 * exp(Float64(log(Float64(-Float64(im_m * Float64(im_m / re)))) * 0.5)));
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im_m, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end
im_m = abs(im);
function tmp_2 = code(re, im_m)
	tmp = 0.0;
	if (re <= -1.7e+157)
		tmp = 0.5 * exp((log(-(im_m * (im_m / re))) * 0.5));
	else
		tmp = sqrt(((hypot(im_m, re) + re) * 2.0)) * 0.5;
	end
	tmp_2 = tmp;
end
im_m = N[Abs[im], $MachinePrecision]
code[re_, im$95$m_] := If[LessEqual[re, -1.7e+157], N[(0.5 * N[Exp[N[(N[Log[(-N[(im$95$m * N[(im$95$m / re), $MachinePrecision]), $MachinePrecision])], $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im$95$m ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}
im_m = \left|im\right|

\\
\begin{array}{l}
\mathbf{if}\;re \leq -1.7 \cdot 10^{+157}:\\
\;\;\;\;0.5 \cdot e^{\log \left(-im\_m \cdot \frac{im\_m}{re}\right) \cdot 0.5}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < -1.6999999999999999e157

    1. Initial program 2.6%

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

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

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

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

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

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

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

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{{\left(2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)\right)}^{\frac{1}{2}}} \]
      9. pow-to-expN/A

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

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

        \[\leadsto \frac{1}{2} \cdot e^{\color{blue}{\log \left(2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)\right) \cdot \frac{1}{2}}} \]
    3. Applied rewrites32.3%

      \[\leadsto 0.5 \cdot \color{blue}{e^{\log \left(\left(\mathsf{hypot}\left(im, re\right) + re\right) \cdot 2\right) \cdot 0.5}} \]
    4. Taylor expanded in re around -inf

      \[\leadsto \frac{1}{2} \cdot e^{\log \color{blue}{\left(-1 \cdot \frac{{im}^{2}}{re}\right)} \cdot \frac{1}{2}} \]
    5. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(\color{blue}{-1} \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      2. pow2N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-1 \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      3. pow2N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-1 \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      4. +-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-1 \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      5. pow2N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-1 \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      6. pow2N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-1 \cdot \frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      7. mul-1-negN/A

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

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

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-\frac{{im}^{2}}{re}\right) \cdot \frac{1}{2}} \]
      10. pow2N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-\frac{im \cdot im}{re}\right) \cdot \frac{1}{2}} \]
      11. lower-*.f6450.7

        \[\leadsto 0.5 \cdot e^{\log \left(-\frac{im \cdot im}{re}\right) \cdot 0.5} \]
    6. Applied rewrites50.7%

      \[\leadsto 0.5 \cdot e^{\log \color{blue}{\left(-\frac{im \cdot im}{re}\right)} \cdot 0.5} \]
    7. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-\frac{im \cdot im}{re}\right) \cdot \frac{1}{2}} \]
      2. lift-/.f64N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-\frac{im \cdot im}{re}\right) \cdot \frac{1}{2}} \]
      3. associate-/l*N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-im \cdot \frac{im}{re}\right) \cdot \frac{1}{2}} \]
      4. lower-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot e^{\log \left(-im \cdot \frac{im}{re}\right) \cdot \frac{1}{2}} \]
      5. lower-/.f6462.3

        \[\leadsto 0.5 \cdot e^{\log \left(-im \cdot \frac{im}{re}\right) \cdot 0.5} \]
    8. Applied rewrites62.3%

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

    if -1.6999999999999999e157 < re

    1. Initial program 47.2%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]
    3. Applied rewrites85.8%

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

Alternative 3: 81.9% accurate, 1.1× speedup?

\[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -2.7 \cdot 10^{+152}:\\ \;\;\;\;0.5 \cdot \sqrt{-\frac{im\_m \cdot im\_m}{re}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\left(\mathsf{hypot}\left(im\_m, re\right) + re\right) \cdot 2} \cdot 0.5\\ \end{array} \end{array} \]
im_m = (fabs.f64 im)
(FPCore (re im_m)
 :precision binary64
 (if (<= re -2.7e+152)
   (* 0.5 (sqrt (- (/ (* im_m im_m) re))))
   (* (sqrt (* (+ (hypot im_m re) re) 2.0)) 0.5)))
im_m = fabs(im);
double code(double re, double im_m) {
	double tmp;
	if (re <= -2.7e+152) {
		tmp = 0.5 * sqrt(-((im_m * im_m) / re));
	} else {
		tmp = sqrt(((hypot(im_m, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}
im_m = Math.abs(im);
public static double code(double re, double im_m) {
	double tmp;
	if (re <= -2.7e+152) {
		tmp = 0.5 * Math.sqrt(-((im_m * im_m) / re));
	} else {
		tmp = Math.sqrt(((Math.hypot(im_m, re) + re) * 2.0)) * 0.5;
	}
	return tmp;
}
im_m = math.fabs(im)
def code(re, im_m):
	tmp = 0
	if re <= -2.7e+152:
		tmp = 0.5 * math.sqrt(-((im_m * im_m) / re))
	else:
		tmp = math.sqrt(((math.hypot(im_m, re) + re) * 2.0)) * 0.5
	return tmp
im_m = abs(im)
function code(re, im_m)
	tmp = 0.0
	if (re <= -2.7e+152)
		tmp = Float64(0.5 * sqrt(Float64(-Float64(Float64(im_m * im_m) / re))));
	else
		tmp = Float64(sqrt(Float64(Float64(hypot(im_m, re) + re) * 2.0)) * 0.5);
	end
	return tmp
end
im_m = abs(im);
function tmp_2 = code(re, im_m)
	tmp = 0.0;
	if (re <= -2.7e+152)
		tmp = 0.5 * sqrt(-((im_m * im_m) / re));
	else
		tmp = sqrt(((hypot(im_m, re) + re) * 2.0)) * 0.5;
	end
	tmp_2 = tmp;
end
im_m = N[Abs[im], $MachinePrecision]
code[re_, im$95$m_] := If[LessEqual[re, -2.7e+152], N[(0.5 * N[Sqrt[(-N[(N[(im$95$m * im$95$m), $MachinePrecision] / re), $MachinePrecision])], $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(N[(N[Sqrt[im$95$m ^ 2 + re ^ 2], $MachinePrecision] + re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}
im_m = \left|im\right|

\\
\begin{array}{l}
\mathbf{if}\;re \leq -2.7 \cdot 10^{+152}:\\
\;\;\;\;0.5 \cdot \sqrt{-\frac{im\_m \cdot im\_m}{re}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if re < -2.70000000000000015e152

    1. Initial program 2.7%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
    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-*.f6453.1

        \[\leadsto 0.5 \cdot \sqrt{-\frac{im \cdot im}{re}} \]
    4. Applied rewrites53.1%

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

    if -2.70000000000000015e152 < re

    1. Initial program 47.3%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \cdot \frac{1}{2}} \]
    3. Applied rewrites86.0%

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

Alternative 4: 70.1% accurate, 1.1× speedup?

\[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq -3.1 \cdot 10^{+63}:\\ \;\;\;\;0.5 \cdot \sqrt{-\frac{im\_m \cdot im\_m}{re}}\\ \mathbf{elif}\;re \leq 1.16 \cdot 10^{+23}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot im\_m}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(\sqrt{re} \cdot 2\right)\\ \end{array} \end{array} \]
im_m = (fabs.f64 im)
(FPCore (re im_m)
 :precision binary64
 (if (<= re -3.1e+63)
   (* 0.5 (sqrt (- (/ (* im_m im_m) re))))
   (if (<= re 1.16e+23)
     (* 0.5 (sqrt (* 2.0 im_m)))
     (* 0.5 (* (sqrt re) 2.0)))))
im_m = fabs(im);
double code(double re, double im_m) {
	double tmp;
	if (re <= -3.1e+63) {
		tmp = 0.5 * sqrt(-((im_m * im_m) / re));
	} else if (re <= 1.16e+23) {
		tmp = 0.5 * sqrt((2.0 * im_m));
	} else {
		tmp = 0.5 * (sqrt(re) * 2.0);
	}
	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+63)) then
        tmp = 0.5d0 * sqrt(-((im_m * im_m) / re))
    else if (re <= 1.16d+23) then
        tmp = 0.5d0 * sqrt((2.0d0 * im_m))
    else
        tmp = 0.5d0 * (sqrt(re) * 2.0d0)
    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+63) {
		tmp = 0.5 * Math.sqrt(-((im_m * im_m) / re));
	} else if (re <= 1.16e+23) {
		tmp = 0.5 * Math.sqrt((2.0 * im_m));
	} else {
		tmp = 0.5 * (Math.sqrt(re) * 2.0);
	}
	return tmp;
}
im_m = math.fabs(im)
def code(re, im_m):
	tmp = 0
	if re <= -3.1e+63:
		tmp = 0.5 * math.sqrt(-((im_m * im_m) / re))
	elif re <= 1.16e+23:
		tmp = 0.5 * math.sqrt((2.0 * im_m))
	else:
		tmp = 0.5 * (math.sqrt(re) * 2.0)
	return tmp
im_m = abs(im)
function code(re, im_m)
	tmp = 0.0
	if (re <= -3.1e+63)
		tmp = Float64(0.5 * sqrt(Float64(-Float64(Float64(im_m * im_m) / re))));
	elseif (re <= 1.16e+23)
		tmp = Float64(0.5 * sqrt(Float64(2.0 * im_m)));
	else
		tmp = Float64(0.5 * Float64(sqrt(re) * 2.0));
	end
	return tmp
end
im_m = abs(im);
function tmp_2 = code(re, im_m)
	tmp = 0.0;
	if (re <= -3.1e+63)
		tmp = 0.5 * sqrt(-((im_m * im_m) / re));
	elseif (re <= 1.16e+23)
		tmp = 0.5 * sqrt((2.0 * im_m));
	else
		tmp = 0.5 * (sqrt(re) * 2.0);
	end
	tmp_2 = tmp;
end
im_m = N[Abs[im], $MachinePrecision]
code[re_, im$95$m_] := If[LessEqual[re, -3.1e+63], N[(0.5 * N[Sqrt[(-N[(N[(im$95$m * im$95$m), $MachinePrecision] / re), $MachinePrecision])], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 1.16e+23], N[(0.5 * N[Sqrt[N[(2.0 * im$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(N[Sqrt[re], $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
im_m = \left|im\right|

\\
\begin{array}{l}
\mathbf{if}\;re \leq -3.1 \cdot 10^{+63}:\\
\;\;\;\;0.5 \cdot \sqrt{-\frac{im\_m \cdot im\_m}{re}}\\

\mathbf{elif}\;re \leq 1.16 \cdot 10^{+23}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot im\_m}\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(\sqrt{re} \cdot 2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if re < -3.1000000000000001e63

    1. Initial program 8.2%

      \[0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} + re\right)} \]
    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-*.f6450.5

        \[\leadsto 0.5 \cdot \sqrt{-\frac{im \cdot im}{re}} \]
    4. Applied rewrites50.5%

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

    if -3.1000000000000001e63 < re < 1.16e23

    1. Initial program 54.5%

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

      \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{im}} \]
    3. Step-by-step derivation
      1. Applied rewrites73.6%

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

      if 1.16e23 < re

      1. Initial program 38.5%

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
      3. Step-by-step derivation
        1. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \left(\sqrt{2} \cdot \color{blue}{\sqrt{2}}\right)\right) \]
        2. rem-square-sqrtN/A

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

          \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \color{blue}{2}\right) \]
        4. lower-sqrt.f6478.0

          \[\leadsto 0.5 \cdot \left(\sqrt{re} \cdot 2\right) \]
      4. Applied rewrites78.0%

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

    Alternative 5: 64.7% accurate, 1.5× speedup?

    \[\begin{array}{l} im_m = \left|im\right| \\ \begin{array}{l} \mathbf{if}\;re \leq 1.16 \cdot 10^{+23}:\\ \;\;\;\;0.5 \cdot \sqrt{2 \cdot im\_m}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(\sqrt{re} \cdot 2\right)\\ \end{array} \end{array} \]
    im_m = (fabs.f64 im)
    (FPCore (re im_m)
     :precision binary64
     (if (<= re 1.16e+23) (* 0.5 (sqrt (* 2.0 im_m))) (* 0.5 (* (sqrt re) 2.0))))
    im_m = fabs(im);
    double code(double re, double im_m) {
    	double tmp;
    	if (re <= 1.16e+23) {
    		tmp = 0.5 * sqrt((2.0 * im_m));
    	} else {
    		tmp = 0.5 * (sqrt(re) * 2.0);
    	}
    	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 <= 1.16d+23) then
            tmp = 0.5d0 * sqrt((2.0d0 * im_m))
        else
            tmp = 0.5d0 * (sqrt(re) * 2.0d0)
        end if
        code = tmp
    end function
    
    im_m = Math.abs(im);
    public static double code(double re, double im_m) {
    	double tmp;
    	if (re <= 1.16e+23) {
    		tmp = 0.5 * Math.sqrt((2.0 * im_m));
    	} else {
    		tmp = 0.5 * (Math.sqrt(re) * 2.0);
    	}
    	return tmp;
    }
    
    im_m = math.fabs(im)
    def code(re, im_m):
    	tmp = 0
    	if re <= 1.16e+23:
    		tmp = 0.5 * math.sqrt((2.0 * im_m))
    	else:
    		tmp = 0.5 * (math.sqrt(re) * 2.0)
    	return tmp
    
    im_m = abs(im)
    function code(re, im_m)
    	tmp = 0.0
    	if (re <= 1.16e+23)
    		tmp = Float64(0.5 * sqrt(Float64(2.0 * im_m)));
    	else
    		tmp = Float64(0.5 * Float64(sqrt(re) * 2.0));
    	end
    	return tmp
    end
    
    im_m = abs(im);
    function tmp_2 = code(re, im_m)
    	tmp = 0.0;
    	if (re <= 1.16e+23)
    		tmp = 0.5 * sqrt((2.0 * im_m));
    	else
    		tmp = 0.5 * (sqrt(re) * 2.0);
    	end
    	tmp_2 = tmp;
    end
    
    im_m = N[Abs[im], $MachinePrecision]
    code[re_, im$95$m_] := If[LessEqual[re, 1.16e+23], N[(0.5 * N[Sqrt[N[(2.0 * im$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(N[Sqrt[re], $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    im_m = \left|im\right|
    
    \\
    \begin{array}{l}
    \mathbf{if}\;re \leq 1.16 \cdot 10^{+23}:\\
    \;\;\;\;0.5 \cdot \sqrt{2 \cdot im\_m}\\
    
    \mathbf{else}:\\
    \;\;\;\;0.5 \cdot \left(\sqrt{re} \cdot 2\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if re < 1.16e23

      1. Initial program 42.8%

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

        \[\leadsto \frac{1}{2} \cdot \sqrt{2 \cdot \color{blue}{im}} \]
      3. Step-by-step derivation
        1. Applied rewrites60.8%

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

        if 1.16e23 < re

        1. Initial program 38.5%

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

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
        3. Step-by-step derivation
          1. unpow2N/A

            \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \left(\sqrt{2} \cdot \color{blue}{\sqrt{2}}\right)\right) \]
          2. rem-square-sqrtN/A

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

            \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \color{blue}{2}\right) \]
          4. lower-sqrt.f6478.0

            \[\leadsto 0.5 \cdot \left(\sqrt{re} \cdot 2\right) \]
        4. Applied rewrites78.0%

          \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{re} \cdot 2\right)} \]
      4. Recombined 2 regimes into one program.
      5. Add Preprocessing

      Alternative 6: 26.0% accurate, 2.5× speedup?

      \[\begin{array}{l} im_m = \left|im\right| \\ 0.5 \cdot \left(\sqrt{re} \cdot 2\right) \end{array} \]
      im_m = (fabs.f64 im)
      (FPCore (re im_m) :precision binary64 (* 0.5 (* (sqrt re) 2.0)))
      im_m = fabs(im);
      double code(double re, double im_m) {
      	return 0.5 * (sqrt(re) * 2.0);
      }
      
      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(re) * 2.0d0)
      end function
      
      im_m = Math.abs(im);
      public static double code(double re, double im_m) {
      	return 0.5 * (Math.sqrt(re) * 2.0);
      }
      
      im_m = math.fabs(im)
      def code(re, im_m):
      	return 0.5 * (math.sqrt(re) * 2.0)
      
      im_m = abs(im)
      function code(re, im_m)
      	return Float64(0.5 * Float64(sqrt(re) * 2.0))
      end
      
      im_m = abs(im);
      function tmp = code(re, im_m)
      	tmp = 0.5 * (sqrt(re) * 2.0);
      end
      
      im_m = N[Abs[im], $MachinePrecision]
      code[re_, im$95$m_] := N[(0.5 * N[(N[Sqrt[re], $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      im_m = \left|im\right|
      
      \\
      0.5 \cdot \left(\sqrt{re} \cdot 2\right)
      \end{array}
      
      Derivation
      1. Initial program 41.8%

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{re} \cdot {\left(\sqrt{2}\right)}^{2}\right)} \]
      3. Step-by-step derivation
        1. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \left(\sqrt{2} \cdot \color{blue}{\sqrt{2}}\right)\right) \]
        2. rem-square-sqrtN/A

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

          \[\leadsto \frac{1}{2} \cdot \left(\sqrt{re} \cdot \color{blue}{2}\right) \]
        4. lower-sqrt.f6426.0

          \[\leadsto 0.5 \cdot \left(\sqrt{re} \cdot 2\right) \]
      4. Applied rewrites26.0%

        \[\leadsto 0.5 \cdot \color{blue}{\left(\sqrt{re} \cdot 2\right)} \]
      5. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2025101 
      (FPCore (re im)
        :name "math.sqrt on complex, real part"
        :precision binary64
        (* 0.5 (sqrt (* 2.0 (+ (sqrt (+ (* re re) (* im im))) re)))))