CLOG, CLOGF, CLOGL - reference manual online

Natural logarithm of a complex number.

CLOG(3)                             Linux Programmer's Manual                             CLOG(3)

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 │ └─────────────────────────┴───────────────┴─────────┘
CONFORMING TO 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 4.04 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
2015-04-19 CLOG(3)
This manual Reference Other manuals
clog(3) referred by cacos(3) | casin(3) | catan(3) | cexp(3) | clog10(3) | clog2(3) | complex(7) | log(3)
refer to attributes(7) | cabs(3) | cexp(3) | clog10(3) | clog2(3) | complex(7)