CARG
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Page Index
NAME
carg, cargf, cargl - calculate the complex argument
SYNOPSIS
#include <complex.h>
double carg(double complex z);
float cargf(float complex z);
long double cargl(long double complex z);
Link with -lm.
DESCRIPTION
These functions calculate the complex argument (also called phase angle) of
z,
with a branch cut along the negative real axis.
A complex number can be described by two real coordinates.
One may use rectangular coordinates and gets
z = x + I * y
where
x = creal(z)
and
y = cimag(z).
Or one may use polar coordinates and gets
z = r * cexp(I * a)
where
r = cabs(z)
is the "radius", the "modulus", the absolute value of
z,
and
a = carg(z)
is the "phase angle", the argument of
z.
One has:
tan(carg(z)) = cimag(z) / creal(z)
RETURN VALUE
The return value is in the range of [-pi,pi].
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
|
|
carg(),
cargf(),
cargl()
| Thread safety | MT-Safe
|
CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.
SEE ALSO
cabs(3),
complex(7)
COLOPHON
This page is part of release 5.10 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/.