\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\begin{array}{l}
\mathbf{if}\;re \le -2.552702335522331775782681989067170419459 \cdot 10^{114}:\\
\;\;\;\;\frac{1}{\sqrt{\log 10}} \cdot \left(1 \cdot \log \left({\left(-1 \cdot re\right)}^{\left(\frac{1}{\sqrt{\log 10}}\right)}\right)\right)\\
\mathbf{elif}\;re \le -8.357854099413858949922341791993400005698 \cdot 10^{-296}:\\
\;\;\;\;\frac{1}{\sqrt{\log 10}} \cdot \left(1 \cdot \log \left({\left(\sqrt{re \cdot re + im \cdot im}\right)}^{\left(\frac{1}{\sqrt{\log 10}}\right)}\right)\right)\\
\mathbf{elif}\;re \le 7.758435713562231820695193588189493548713 \cdot 10^{-281}:\\
\;\;\;\;\frac{\log im}{\log 10}\\
\mathbf{elif}\;re \le 1.241086545067041095458499268505642473269 \cdot 10^{67}:\\
\;\;\;\;\frac{1}{\sqrt{\log 10}} \cdot \left(1 \cdot \log \left({\left(\sqrt{re \cdot re + im \cdot im}\right)}^{\left(\frac{1}{\sqrt{\log 10}}\right)}\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{\sqrt{\log 10}} \cdot \left(1 \cdot \log \left({re}^{\left(\frac{1}{\sqrt{\log 10}}\right)}\right)\right)\\
\end{array}double f(double re, double im) {
double r99347 = re;
double r99348 = r99347 * r99347;
double r99349 = im;
double r99350 = r99349 * r99349;
double r99351 = r99348 + r99350;
double r99352 = sqrt(r99351);
double r99353 = log(r99352);
double r99354 = 10.0;
double r99355 = log(r99354);
double r99356 = r99353 / r99355;
return r99356;
}
double f(double re, double im) {
double r99357 = re;
double r99358 = -2.552702335522332e+114;
bool r99359 = r99357 <= r99358;
double r99360 = 1.0;
double r99361 = 10.0;
double r99362 = log(r99361);
double r99363 = sqrt(r99362);
double r99364 = r99360 / r99363;
double r99365 = -1.0;
double r99366 = r99365 * r99357;
double r99367 = pow(r99366, r99364);
double r99368 = log(r99367);
double r99369 = r99360 * r99368;
double r99370 = r99364 * r99369;
double r99371 = -8.357854099413859e-296;
bool r99372 = r99357 <= r99371;
double r99373 = r99357 * r99357;
double r99374 = im;
double r99375 = r99374 * r99374;
double r99376 = r99373 + r99375;
double r99377 = sqrt(r99376);
double r99378 = pow(r99377, r99364);
double r99379 = log(r99378);
double r99380 = r99360 * r99379;
double r99381 = r99364 * r99380;
double r99382 = 7.758435713562232e-281;
bool r99383 = r99357 <= r99382;
double r99384 = log(r99374);
double r99385 = r99384 / r99362;
double r99386 = 1.2410865450670411e+67;
bool r99387 = r99357 <= r99386;
double r99388 = pow(r99357, r99364);
double r99389 = log(r99388);
double r99390 = r99360 * r99389;
double r99391 = r99364 * r99390;
double r99392 = r99387 ? r99381 : r99391;
double r99393 = r99383 ? r99385 : r99392;
double r99394 = r99372 ? r99381 : r99393;
double r99395 = r99359 ? r99370 : r99394;
return r99395;
}



Bits error versus re



Bits error versus im
Results
if re < -2.552702335522332e+114Initial program 53.6
rmApplied add-sqr-sqrt53.6
Applied pow153.6
Applied log-pow53.6
Applied times-frac53.6
rmApplied add-log-exp53.6
Simplified53.5
rmApplied *-un-lft-identity53.5
Taylor expanded around -inf 8.4
if -2.552702335522332e+114 < re < -8.357854099413859e-296 or 7.758435713562232e-281 < re < 1.2410865450670411e+67Initial program 21.6
rmApplied add-sqr-sqrt21.6
Applied pow121.6
Applied log-pow21.6
Applied times-frac21.6
rmApplied add-log-exp21.6
Simplified21.4
rmApplied *-un-lft-identity21.4
if -8.357854099413859e-296 < re < 7.758435713562232e-281Initial program 29.8
Taylor expanded around 0 34.6
if 1.2410865450670411e+67 < re Initial program 45.2
rmApplied add-sqr-sqrt45.2
Applied pow145.2
Applied log-pow45.2
Applied times-frac45.2
rmApplied add-log-exp45.2
Simplified45.1
rmApplied *-un-lft-identity45.1
Taylor expanded around inf 9.9
Final simplification17.5
herbie shell --seed 2019352
(FPCore (re im)
:name "math.log10 on complex, real part"
:precision binary64
(/ (log (sqrt (+ (* re re) (* im im)))) (log 10)))