\frac{\tan^{-1}_* \frac{im}{re}}{\log 10}\mathsf{log1p}\left(\mathsf{expm1}\left(\frac{1}{\sqrt{\log 10}} \cdot \left(\tan^{-1}_* \frac{im}{re} \cdot \sqrt{\frac{1}{\log 10}}\right)\right)\right)double f(double re, double im) {
double r30083 = im;
double r30084 = re;
double r30085 = atan2(r30083, r30084);
double r30086 = 10.0;
double r30087 = log(r30086);
double r30088 = r30085 / r30087;
return r30088;
}
double f(double re, double im) {
double r30089 = 1.0;
double r30090 = 10.0;
double r30091 = log(r30090);
double r30092 = sqrt(r30091);
double r30093 = r30089 / r30092;
double r30094 = im;
double r30095 = re;
double r30096 = atan2(r30094, r30095);
double r30097 = r30089 / r30091;
double r30098 = sqrt(r30097);
double r30099 = r30096 * r30098;
double r30100 = r30093 * r30099;
double r30101 = expm1(r30100);
double r30102 = log1p(r30101);
return r30102;
}



Bits error versus re



Bits error versus im
Results
Initial program 0.8
rmApplied log1p-expm1-u0.7
rmApplied add-sqr-sqrt0.7
Applied *-un-lft-identity0.7
Applied times-frac0.7
Taylor expanded around 0 0.7
Final simplification0.7
herbie shell --seed 2019350 +o rules:numerics
(FPCore (re im)
:name "math.log10 on complex, imaginary part"
:precision binary64
(/ (atan2 im re) (log 10)))