carg, cargf, cargl - calculate the complex argument
double carg(double complex z);
float cargf(float complex z);
long double cargl(long double complex z);
Link with -lm
These functions calculate the complex argument (also called phase angle) of
, 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
a = carg(z)
is the "phase angle", the argument
tan(carg(z)) = cimag(z) / creal(z)
The return value is the range of [-pi,pi].
These functions first appeared in glibc in version 2.1.
For an explanation of the terms used in this section, see attributes(7)
|carg (), cargf (), cargl ()
C99, POSIX.1-2001, POSIX.1-2008.
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