clog (3) Linux Manual Page
clog, clogf, clogl – natural logarithm of a complex number
Synopsis
#include <complex.h> double complex clog(double complex z);
float complex clogf(float complex z);
long double complex clogl(long double complex z);
Link with -lm.
Description
These functions calculate the complex natural logarithm of z, with a branch cut along the negative real axis.The logarithm clog() is the inverse function of the exponential cexp(3). Thus, if y = clog(z), then z = cexp(y). The imaginary part of y is chosen in the interval [-pi,pi].
One has:
clog(z) = log(cabs(z)) + I * carg(z)Note that z close to zero will cause an overflow.
Versions
These functions first appeared in glibc in version 2.1.Attributes
For an explanation of the terms used in this section, see attributes(7).| Interface | Attribute | Value |
| clog(), clogf(), clogl() | Thread safety | MT-Safe |