0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\begin{array}{l}
\mathbf{if}\;re \le -2.222006465724332039862348815623896484961 \cdot 10^{103}:\\
\;\;\;\;\sqrt{\left(-2 \cdot re\right) \cdot 2} \cdot 0.5\\
\mathbf{elif}\;re \le -1.511080944730437448708717796208898738523 \cdot 10^{-305}:\\
\;\;\;\;0.5 \cdot \sqrt{\left(\sqrt{\sqrt[3]{\sqrt{re \cdot re + im \cdot im}}} \cdot \left(\sqrt{\sqrt[3]{\sqrt{re \cdot re + im \cdot im}}} \cdot \left|\sqrt[3]{re \cdot re + im \cdot im}\right|\right) - re\right) \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{\frac{im \cdot im}{\sqrt{re \cdot re + im \cdot im} + re} \cdot 2}\\
\end{array}double f(double re, double im) {
double r983768 = 0.5;
double r983769 = 2.0;
double r983770 = re;
double r983771 = r983770 * r983770;
double r983772 = im;
double r983773 = r983772 * r983772;
double r983774 = r983771 + r983773;
double r983775 = sqrt(r983774);
double r983776 = r983775 - r983770;
double r983777 = r983769 * r983776;
double r983778 = sqrt(r983777);
double r983779 = r983768 * r983778;
return r983779;
}
double f(double re, double im) {
double r983780 = re;
double r983781 = -2.222006465724332e+103;
bool r983782 = r983780 <= r983781;
double r983783 = -2.0;
double r983784 = r983783 * r983780;
double r983785 = 2.0;
double r983786 = r983784 * r983785;
double r983787 = sqrt(r983786);
double r983788 = 0.5;
double r983789 = r983787 * r983788;
double r983790 = -1.5110809447304374e-305;
bool r983791 = r983780 <= r983790;
double r983792 = r983780 * r983780;
double r983793 = im;
double r983794 = r983793 * r983793;
double r983795 = r983792 + r983794;
double r983796 = sqrt(r983795);
double r983797 = cbrt(r983796);
double r983798 = sqrt(r983797);
double r983799 = cbrt(r983795);
double r983800 = fabs(r983799);
double r983801 = r983798 * r983800;
double r983802 = r983798 * r983801;
double r983803 = r983802 - r983780;
double r983804 = r983803 * r983785;
double r983805 = sqrt(r983804);
double r983806 = r983788 * r983805;
double r983807 = r983796 + r983780;
double r983808 = r983794 / r983807;
double r983809 = r983808 * r983785;
double r983810 = sqrt(r983809);
double r983811 = r983788 * r983810;
double r983812 = r983791 ? r983806 : r983811;
double r983813 = r983782 ? r983789 : r983812;
return r983813;
}



Bits error versus re



Bits error versus im
Results
if re < -2.222006465724332e+103Initial program 52.0
Taylor expanded around -inf 10.1
if -2.222006465724332e+103 < re < -1.5110809447304374e-305Initial program 20.4
rmApplied add-cube-cbrt20.6
Applied sqrt-prod20.7
Simplified20.7
rmApplied add-sqr-sqrt20.7
Applied cbrt-prod20.6
Applied sqrt-prod20.7
Applied associate-*r*20.7
if -1.5110809447304374e-305 < re Initial program 45.4
rmApplied flip--45.3
Simplified35.6
Final simplification26.4
herbie shell --seed 2019172
(FPCore (re im)
:name "math.sqrt on complex, imaginary part, im greater than 0 branch"
(* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))