CACOS(3)

NAME
cacos, cacosf, cacosl - complex arc cosine

SYNOPSIS
#include <complex.h>

double complex cacos(double complex z);
float complex cacosf(float complex z);
long double complex cacosl(long double complex z);

Link with -lm.

DESCRIPTION
The cacos() function calculates the complex arc cosine of z. If y = cacos(z), then z = ccos(y). The real part of y is chosen in the interval [0,pi].

One has:
    cacos(z) = -i clog(z + csqrt(z * z - 1))

VERSIONS
These functions first appeared in glibc in version 2.1.

CONFORMING TO
C99.

SEE ALSO
ccos(3), clog(3), complex(7)

COLOPHON
This page is part of release 3.15 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/.