NAME¶
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 |
C99, POSIX.1-2001, POSIX.1-2008.
SEE ALSO¶
cabs(3),
cexp(3),
clog10(3),
clog2(3),
complex(7)
COLOPHON¶
This page is part of release 4.10 of the Linux
man-pages project. A
description of the project, information about reporting bugs, and the latest
version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
