0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\begin{array}{l}
\mathbf{if}\;re \le -2.393156389015936 \cdot 10^{-104}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(-2 \cdot re\right)}\\
\mathbf{elif}\;re \le 4.88349855638349569 \cdot 10^{-298}:\\
\;\;\;\;0.5 \cdot \frac{\sqrt{2 \cdot {im}^{2}}}{\sqrt{\sqrt{re \cdot re + im \cdot im} + re}}\\
\mathbf{elif}\;re \le 4.0892765348340891 \cdot 10^{-181}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im \cdot \frac{im}{im + re}\right)}\\
\mathbf{elif}\;re \le 6.2056800547434506 \cdot 10^{137}:\\
\;\;\;\;0.5 \cdot \frac{\sqrt{2 \cdot {im}^{2}}}{\sqrt{\sqrt{re \cdot re + im \cdot im} + re}}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im \cdot \frac{im}{re + re}\right)}\\
\end{array}double code(double re, double im) {
return (0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re))));
}
double code(double re, double im) {
double VAR;
if ((re <= -2.393156389015936e-104)) {
VAR = (0.5 * sqrt((2.0 * (-2.0 * re))));
} else {
double VAR_1;
if ((re <= 4.883498556383496e-298)) {
VAR_1 = (0.5 * (sqrt((2.0 * pow(im, 2.0))) / sqrt((sqrt(((re * re) + (im * im))) + re))));
} else {
double VAR_2;
if ((re <= 4.089276534834089e-181)) {
VAR_2 = (0.5 * sqrt((2.0 * (im * (im / (im + re))))));
} else {
double VAR_3;
if ((re <= 6.205680054743451e+137)) {
VAR_3 = (0.5 * (sqrt((2.0 * pow(im, 2.0))) / sqrt((sqrt(((re * re) + (im * im))) + re))));
} else {
VAR_3 = (0.5 * sqrt((2.0 * (im * (im / (re + re))))));
}
VAR_2 = VAR_3;
}
VAR_1 = VAR_2;
}
VAR = VAR_1;
}
return VAR;
}



Bits error versus re



Bits error versus im
Results
if re < -2.393156389015936e-104Initial program 33.4
Taylor expanded around -inf 20.6
if -2.393156389015936e-104 < re < 4.883498556383496e-298 or 4.089276534834089e-181 < re < 6.205680054743451e+137Initial program 34.6
rmApplied flip--36.6
Simplified29.1
rmApplied associate-*r/29.1
Applied sqrt-div28.5
if 4.883498556383496e-298 < re < 4.089276534834089e-181Initial program 30.9
rmApplied flip--30.4
Simplified30.4
rmApplied *-un-lft-identity30.4
Applied add-sqr-sqrt48.7
Applied unpow-prod-down48.7
Applied times-frac47.8
Simplified47.8
Simplified28.6
Taylor expanded around 0 35.3
if 6.205680054743451e+137 < re Initial program 63.4
rmApplied flip--63.4
Simplified50.1
rmApplied *-un-lft-identity50.1
Applied add-sqr-sqrt56.5
Applied unpow-prod-down56.5
Applied times-frac56.4
Simplified56.3
Simplified49.7
Taylor expanded around inf 23.4
Final simplification25.8
herbie shell --seed 2020092
(FPCore (re im)
:name "math.sqrt on complex, imaginary part, im greater than 0 branch"
:precision binary64
(* 0.5 (sqrt (* 2 (- (sqrt (+ (* re re) (* im im))) re)))))