CARG
Section: Linux Programmer's Manual (3)
Updated: 20170915
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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  MTSafe

CONFORMING TO
C99, POSIX.12001, POSIX.12008.
SEE ALSO
cabs(3),
complex(7)
COLOPHON
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