table of contents
carg(3) | Library Functions Manual | carg(3) |
NAME¶
carg, cargf, cargl - calculate the complex argument
LIBRARY¶
Math library (libm, -lm)
SYNOPSIS¶
#include <complex.h>
double carg(double complex z); float cargf(float complex z); long double cargl(long double complex z);
DESCRIPTION¶
These functions calculate the complex argument (also called phase angle) of z, 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, 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 in the range of [-pi,pi].
VERSIONS¶
These functions were added in glibc 2.1.
ATTRIBUTES¶
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
carg (), cargf (), cargl () | Thread safety | MT-Safe |
STANDARDS¶
C99, POSIX.1-2001, POSIX.1-2008.
SEE ALSO¶
2022-12-15 | Linux man-pages 6.03 |