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clog(3) | Library Functions Manual | clog(3) |
NAME¶
clog, clogf, clogl - natural logarithm of a complex number
LIBRARY¶
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 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.
ATTRIBUTES¶
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
clog (), clogf (), clogl () | Thread safety | MT-Safe |
STANDARDS¶
C11, POSIX.1-2008.
HISTORY¶
glibc 2.1. C99, POSIX.1-2001.
SEE ALSO¶
2023-03-30 | Linux man-pages 6.04 |