0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}\begin{array}{l}
\mathbf{if}\;re \le -2.463228932581569 \cdot 10^{122}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(-1 \cdot re - re\right)}\\
\mathbf{elif}\;re \le -7.36720432236371972 \cdot 10^{-267}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\left(\sqrt[3]{\sqrt{re \cdot re + im \cdot im}} \cdot \sqrt[3]{\sqrt{re \cdot re + im \cdot im}}\right) \cdot \sqrt[3]{\sqrt{re \cdot re + im \cdot im}} - re\right)}\\
\mathbf{elif}\;re \le -8.0555860969017378 \cdot 10^{-305}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(-\left(re + im\right)\right)}\\
\mathbf{elif}\;re \le 5.3944762495838531 \cdot 10^{143}:\\
\;\;\;\;0.5 \cdot \left(\sqrt{2} \cdot \left|\frac{\left|im\right|}{\sqrt{\sqrt{re \cdot re + im \cdot im} + re}}\right|\right)\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im \cdot \frac{im}{2 \cdot re}\right)}\\
\end{array}double f(double re, double im) {
double r20165 = 0.5;
double r20166 = 2.0;
double r20167 = re;
double r20168 = r20167 * r20167;
double r20169 = im;
double r20170 = r20169 * r20169;
double r20171 = r20168 + r20170;
double r20172 = sqrt(r20171);
double r20173 = r20172 - r20167;
double r20174 = r20166 * r20173;
double r20175 = sqrt(r20174);
double r20176 = r20165 * r20175;
return r20176;
}
double f(double re, double im) {
double r20177 = re;
double r20178 = -2.463228932581569e+122;
bool r20179 = r20177 <= r20178;
double r20180 = 0.5;
double r20181 = 2.0;
double r20182 = -1.0;
double r20183 = r20182 * r20177;
double r20184 = r20183 - r20177;
double r20185 = r20181 * r20184;
double r20186 = sqrt(r20185);
double r20187 = r20180 * r20186;
double r20188 = -7.36720432236372e-267;
bool r20189 = r20177 <= r20188;
double r20190 = r20177 * r20177;
double r20191 = im;
double r20192 = r20191 * r20191;
double r20193 = r20190 + r20192;
double r20194 = sqrt(r20193);
double r20195 = cbrt(r20194);
double r20196 = r20195 * r20195;
double r20197 = r20196 * r20195;
double r20198 = r20197 - r20177;
double r20199 = r20181 * r20198;
double r20200 = sqrt(r20199);
double r20201 = r20180 * r20200;
double r20202 = -8.055586096901738e-305;
bool r20203 = r20177 <= r20202;
double r20204 = r20177 + r20191;
double r20205 = -r20204;
double r20206 = r20181 * r20205;
double r20207 = sqrt(r20206);
double r20208 = r20180 * r20207;
double r20209 = 5.394476249583853e+143;
bool r20210 = r20177 <= r20209;
double r20211 = sqrt(r20181);
double r20212 = fabs(r20191);
double r20213 = r20194 + r20177;
double r20214 = sqrt(r20213);
double r20215 = r20212 / r20214;
double r20216 = fabs(r20215);
double r20217 = r20211 * r20216;
double r20218 = r20180 * r20217;
double r20219 = 2.0;
double r20220 = r20219 * r20177;
double r20221 = r20191 / r20220;
double r20222 = r20191 * r20221;
double r20223 = r20181 * r20222;
double r20224 = sqrt(r20223);
double r20225 = r20180 * r20224;
double r20226 = r20210 ? r20218 : r20225;
double r20227 = r20203 ? r20208 : r20226;
double r20228 = r20189 ? r20201 : r20227;
double r20229 = r20179 ? r20187 : r20228;
return r20229;
}



Bits error versus re



Bits error versus im
Results
if re < -2.463228932581569e+122Initial program 55.7
Taylor expanded around -inf 9.5
if -2.463228932581569e+122 < re < -7.36720432236372e-267Initial program 19.7
rmApplied add-cube-cbrt20.2
if -7.36720432236372e-267 < re < -8.055586096901738e-305Initial program 29.8
rmApplied flip--30.6
Simplified30.6
Taylor expanded around -inf 30.6
if -8.055586096901738e-305 < re < 5.394476249583853e+143Initial program 40.2
rmApplied flip--40.0
Simplified31.4
rmApplied add-sqr-sqrt31.5
Applied add-sqr-sqrt31.5
Applied times-frac31.5
Simplified31.3
Simplified29.2
rmApplied sqrt-prod29.3
Simplified20.6
if 5.394476249583853e+143 < re Initial program 63.1
rmApplied flip--63.1
Simplified48.1
rmApplied *-un-lft-identity48.1
Applied add-sqr-sqrt56.3
Applied unpow-prod-down56.3
Applied times-frac56.1
Simplified56.0
Simplified47.7
Taylor expanded around inf 24.1
Final simplification19.5
herbie shell --seed 2020025
(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)))))