carg(3) - Linux man page
Name
carg, cargf, cargl - calculate the argumentSynopsis
#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).
