.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
.\" Distributed under GPL
.\"
.TH CARG 3 2002-07-28 "" "Linux Programmer's Manual"
.SH NAME
carg, cargf, cargl \- calculate the argument
.SH SYNOPSIS
.B #include <complex.h>
.sp
.BI "double carg(double complex " z ");"
.br
.BI "float cargf(float complex " z ");"
.br
.BI "long double cargl(long double complex " z ");"
.sp
Link with \fI\-lm\fP.
.SH 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).
.LP
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.
.LP
One has tan(carg(z)) = cimag(z) / creal(z).
.SH "RETURN VALUE"
The return value is the range of [\-pi,pi].
.SH "CONFORMING TO"
C99
.SH "SEE ALSO"
.BR cabs (3),
.BR complex (7)