Name
clog, clogf, clogl - natural logarithm of a complex numberLibrary
Math library ( libm ", " -lm )Synopsis
#include <complex.h> double complex clog(double complex z );
float complex clogf(float complex z );
long double complex clogl(long double complex z );
Description
These functions calculate the complex natural logarithm ofz, 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.
Attributes
For an explanation of the terms used in this section, see attributes(7).| Interface | Attribute | Value |
| T} | Thread safety | MT-Safe |