NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | VERSIONS | CONFORMING TO | SEE ALSO | COLOPHON

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

NAME         top

       carg, cargf, cargl - calculate the argument

SYNOPSIS         top

       #include <complex.h>

       double carg(double complex z);
       float cargf(float complex z);
       long double cargl(long double complex z);

       Link with -lm.

DESCRIPTION         top

       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         top

       The return value is the range of [-pi,pi].

VERSIONS         top

       These functions first appeared in glibc in version 2.1.

CONFORMING TO         top

       C99.

SEE ALSO         top

       cabs(3), complex(7)

COLOPHON         top

       This page is part of release 3.23 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                              CARG(3)