EN JA
CARG(3)
CARG(3) Linux Programmer's Manual CARG(3)

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

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 the range of [-pi,pi].

VERSIONS

These functions first appeared in glibc in version 2.1.

CONFORMING TO

C99.

SEE ALSO

cabs(3), complex(7)

COLOPHON

This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.
2008-08-11