0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\begin{array}{l}
\mathbf{if}\;re \le -1.178594449777199163791033377764152427439 \cdot 10^{109}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\left(-re\right) - re\right)}\\
\mathbf{elif}\;re \le -2.831188104063089421579428004178246992819 \cdot 10^{-307}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\sqrt{\sqrt{re \cdot re + im \cdot im}} \cdot \sqrt{\sqrt{re \cdot re + im \cdot im}} - re\right)}\\
\mathbf{elif}\;re \le 1.819440950287977262527658386462127746153 \cdot 10^{151}:\\
\;\;\;\;0.5 \cdot \frac{\sqrt{2}}{\frac{\sqrt{\sqrt{re \cdot re + im \cdot im} + re}}{\left|im\right|}}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \frac{\sqrt{\left(im \cdot im\right) \cdot 2}}{\sqrt{2 \cdot re}}\\
\end{array}double f(double re, double im) {
double r27519 = 0.5;
double r27520 = 2.0;
double r27521 = re;
double r27522 = r27521 * r27521;
double r27523 = im;
double r27524 = r27523 * r27523;
double r27525 = r27522 + r27524;
double r27526 = sqrt(r27525);
double r27527 = r27526 - r27521;
double r27528 = r27520 * r27527;
double r27529 = sqrt(r27528);
double r27530 = r27519 * r27529;
return r27530;
}
double f(double re, double im) {
double r27531 = re;
double r27532 = -1.1785944497771992e+109;
bool r27533 = r27531 <= r27532;
double r27534 = 0.5;
double r27535 = 2.0;
double r27536 = -r27531;
double r27537 = r27536 - r27531;
double r27538 = r27535 * r27537;
double r27539 = sqrt(r27538);
double r27540 = r27534 * r27539;
double r27541 = -2.8311881040630894e-307;
bool r27542 = r27531 <= r27541;
double r27543 = r27531 * r27531;
double r27544 = im;
double r27545 = r27544 * r27544;
double r27546 = r27543 + r27545;
double r27547 = sqrt(r27546);
double r27548 = sqrt(r27547);
double r27549 = r27548 * r27548;
double r27550 = r27549 - r27531;
double r27551 = r27535 * r27550;
double r27552 = sqrt(r27551);
double r27553 = r27534 * r27552;
double r27554 = 1.8194409502879773e+151;
bool r27555 = r27531 <= r27554;
double r27556 = sqrt(r27535);
double r27557 = r27547 + r27531;
double r27558 = sqrt(r27557);
double r27559 = fabs(r27544);
double r27560 = r27558 / r27559;
double r27561 = r27556 / r27560;
double r27562 = r27534 * r27561;
double r27563 = r27545 * r27535;
double r27564 = sqrt(r27563);
double r27565 = 2.0;
double r27566 = r27565 * r27531;
double r27567 = sqrt(r27566);
double r27568 = r27564 / r27567;
double r27569 = r27534 * r27568;
double r27570 = r27555 ? r27562 : r27569;
double r27571 = r27542 ? r27553 : r27570;
double r27572 = r27533 ? r27540 : r27571;
return r27572;
}



Bits error versus re



Bits error versus im
Results
if re < -1.1785944497771992e+109Initial program 54.3
Taylor expanded around -inf 11.4
Simplified11.4
if -1.1785944497771992e+109 < re < -2.8311881040630894e-307Initial program 21.6
rmApplied add-sqr-sqrt21.6
Applied sqrt-prod21.7
if -2.8311881040630894e-307 < re < 1.8194409502879773e+151Initial program 40.8
rmApplied flip--40.6
Applied associate-*r/40.6
Applied sqrt-div40.7
Simplified30.3
rmApplied sqrt-prod30.3
Applied associate-/l*30.4
Simplified20.2
if 1.8194409502879773e+151 < re Initial program 63.8
rmApplied flip--63.8
Applied associate-*r/63.8
Applied sqrt-div63.8
Simplified50.0
Taylor expanded around inf 18.9
Final simplification19.2
herbie shell --seed 2019235
(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)))))