0.5 \cdot \sqrt{2.0 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\begin{array}{l}
\mathbf{if}\;re \le -1.1639866401777603 \cdot 10^{+111}:\\
\;\;\;\;\sqrt{\left(-2 \cdot re\right) \cdot 2.0} \cdot 0.5\\
\mathbf{elif}\;re \le -6.3441075981154 \cdot 10^{-203}:\\
\;\;\;\;0.5 \cdot \sqrt{2.0 \cdot \left(\sqrt{im \cdot im + re \cdot re} - re\right)}\\
\mathbf{elif}\;re \le 1.9683258718073588 \cdot 10^{-248}:\\
\;\;\;\;0.5 \cdot \sqrt{\left(im - re\right) \cdot 2.0}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \frac{\sqrt{\left(im \cdot im\right) \cdot 2.0}}{\sqrt{\sqrt{im \cdot im + re \cdot re} + re}}\\
\end{array}double f(double re, double im) {
double r478106 = 0.5;
double r478107 = 2.0;
double r478108 = re;
double r478109 = r478108 * r478108;
double r478110 = im;
double r478111 = r478110 * r478110;
double r478112 = r478109 + r478111;
double r478113 = sqrt(r478112);
double r478114 = r478113 - r478108;
double r478115 = r478107 * r478114;
double r478116 = sqrt(r478115);
double r478117 = r478106 * r478116;
return r478117;
}
double f(double re, double im) {
double r478118 = re;
double r478119 = -1.1639866401777603e+111;
bool r478120 = r478118 <= r478119;
double r478121 = -2.0;
double r478122 = r478121 * r478118;
double r478123 = 2.0;
double r478124 = r478122 * r478123;
double r478125 = sqrt(r478124);
double r478126 = 0.5;
double r478127 = r478125 * r478126;
double r478128 = -6.3441075981154e-203;
bool r478129 = r478118 <= r478128;
double r478130 = im;
double r478131 = r478130 * r478130;
double r478132 = r478118 * r478118;
double r478133 = r478131 + r478132;
double r478134 = sqrt(r478133);
double r478135 = r478134 - r478118;
double r478136 = r478123 * r478135;
double r478137 = sqrt(r478136);
double r478138 = r478126 * r478137;
double r478139 = 1.9683258718073588e-248;
bool r478140 = r478118 <= r478139;
double r478141 = r478130 - r478118;
double r478142 = r478141 * r478123;
double r478143 = sqrt(r478142);
double r478144 = r478126 * r478143;
double r478145 = r478131 * r478123;
double r478146 = sqrt(r478145);
double r478147 = r478134 + r478118;
double r478148 = sqrt(r478147);
double r478149 = r478146 / r478148;
double r478150 = r478126 * r478149;
double r478151 = r478140 ? r478144 : r478150;
double r478152 = r478129 ? r478138 : r478151;
double r478153 = r478120 ? r478127 : r478152;
return r478153;
}



Bits error versus re



Bits error versus im
Results
if re < -1.1639866401777603e+111Initial program 51.2
Taylor expanded around -inf 9.7
if -1.1639866401777603e+111 < re < -6.3441075981154e-203Initial program 17.7
if -6.3441075981154e-203 < re < 1.9683258718073588e-248Initial program 27.2
Taylor expanded around 0 31.4
if 1.9683258718073588e-248 < re Initial program 46.9
rmApplied flip--46.9
Applied associate-*r/46.9
Applied sqrt-div47.0
Simplified34.9
Final simplification26.1
herbie shell --seed 2019132
(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)))))