\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right)}{\log 10}\begin{array}{l}
\mathbf{if}\;re \le -2.7914972225733451 \cdot 10^{118}:\\
\;\;\;\;\frac{\frac{1}{2}}{\sqrt{\log 10}} \cdot \left(\sqrt{\frac{1}{\log 10}} \cdot \left(-2 \cdot \log \left(\frac{-1}{re}\right)\right)\right)\\
\mathbf{elif}\;re \le -2.263966836247413 \cdot 10^{-261}:\\
\;\;\;\;\frac{\frac{1}{2}}{\sqrt{\log 10}} \cdot \log \left({\left(re \cdot re + im \cdot im\right)}^{\left(\frac{1}{\sqrt{\log 10}}\right)}\right)\\
\mathbf{elif}\;re \le 9.11467363518384614 \cdot 10^{-161}:\\
\;\;\;\;\frac{\sqrt[3]{\frac{1}{2}} \cdot \sqrt[3]{\frac{1}{2}}}{\sqrt{\sqrt{\log 10}}} \cdot \left(\frac{\sqrt[3]{\frac{1}{2}}}{\sqrt{\sqrt{\log 10}}} \cdot \frac{2 \cdot \log im}{\sqrt{\log 10}}\right)\\
\mathbf{elif}\;re \le 2.2325004775726448 \cdot 10^{130}:\\
\;\;\;\;\sqrt{\frac{\frac{1}{2}}{\sqrt{\log 10}}} \cdot \left(\sqrt{\frac{\frac{1}{2}}{\sqrt{\log 10}}} \cdot \frac{\log \left(re \cdot re + im \cdot im\right)}{\sqrt{\log 10}}\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{1}{2}}{\sqrt{\log 10}} \cdot \left(\left(\sqrt{\frac{1}{\log 10}} \cdot \log re\right) \cdot 2\right)\\
\end{array}double code(double re, double im) {
return ((double) (((double) log(((double) sqrt(((double) (((double) (re * re)) + ((double) (im * im)))))))) / ((double) log(10.0))));
}
double code(double re, double im) {
double VAR;
if ((re <= -2.791497222573345e+118)) {
VAR = ((double) (((double) (0.5 / ((double) sqrt(((double) log(10.0)))))) * ((double) (((double) sqrt(((double) (1.0 / ((double) log(10.0)))))) * ((double) (-2.0 * ((double) log(((double) (-1.0 / re))))))))));
} else {
double VAR_1;
if ((re <= -2.263966836247413e-261)) {
VAR_1 = ((double) (((double) (0.5 / ((double) sqrt(((double) log(10.0)))))) * ((double) log(((double) pow(((double) (((double) (re * re)) + ((double) (im * im)))), ((double) (1.0 / ((double) sqrt(((double) log(10.0))))))))))));
} else {
double VAR_2;
if ((re <= 9.114673635183846e-161)) {
VAR_2 = ((double) (((double) (((double) (((double) cbrt(0.5)) * ((double) cbrt(0.5)))) / ((double) sqrt(((double) sqrt(((double) log(10.0)))))))) * ((double) (((double) (((double) cbrt(0.5)) / ((double) sqrt(((double) sqrt(((double) log(10.0)))))))) * ((double) (((double) (2.0 * ((double) log(im)))) / ((double) sqrt(((double) log(10.0))))))))));
} else {
double VAR_3;
if ((re <= 2.232500477572645e+130)) {
VAR_3 = ((double) (((double) sqrt(((double) (0.5 / ((double) sqrt(((double) log(10.0)))))))) * ((double) (((double) sqrt(((double) (0.5 / ((double) sqrt(((double) log(10.0)))))))) * ((double) (((double) log(((double) (((double) (re * re)) + ((double) (im * im)))))) / ((double) sqrt(((double) log(10.0))))))))));
} else {
VAR_3 = ((double) (((double) (0.5 / ((double) sqrt(((double) log(10.0)))))) * ((double) (((double) (((double) sqrt(((double) (1.0 / ((double) log(10.0)))))) * ((double) log(re)))) * 2.0))));
}
VAR_2 = VAR_3;
}
VAR_1 = VAR_2;
}
VAR = VAR_1;
}
return VAR;
}



Bits error versus re



Bits error versus im
Results
if re < -2.7914972225733451e118Initial program 55.7
rmApplied add-sqr-sqrt55.7
Applied pow1/255.7
Applied log-pow55.7
Applied times-frac55.7
Taylor expanded around -inf 8.0
Simplified8.0
if -2.7914972225733451e118 < re < -2.263966836247413e-261Initial program 20.0
rmApplied add-sqr-sqrt20.0
Applied pow1/220.0
Applied log-pow20.0
Applied times-frac20.0
rmApplied add-log-exp20.0
Simplified19.8
if -2.263966836247413e-261 < re < 9.11467363518384614e-161Initial program 31.6
rmApplied add-sqr-sqrt31.6
Applied pow1/231.6
Applied log-pow31.6
Applied times-frac31.5
rmApplied add-sqr-sqrt31.5
Applied sqrt-prod31.9
Applied add-cube-cbrt31.5
Applied times-frac31.5
Applied associate-*l*31.5
Taylor expanded around 0 36.1
Simplified36.1
if 9.11467363518384614e-161 < re < 2.2325004775726448e130Initial program 17.0
rmApplied add-sqr-sqrt17.0
Applied pow1/217.0
Applied log-pow17.0
Applied times-frac16.9
rmApplied add-sqr-sqrt16.9
Applied associate-*l*16.8
if 2.2325004775726448e130 < re Initial program 57.5
rmApplied add-sqr-sqrt57.5
Applied pow1/257.5
Applied log-pow57.5
Applied times-frac57.5
Taylor expanded around inf 8.9
Simplified8.9
Final simplification18.3
herbie shell --seed 2020161
(FPCore (re im)
:name "math.log10 on complex, real part"
:precision binary64
(/ (log (sqrt (+ (* re re) (* im im)))) (log 10.0)))