CACOS

Section: Linux Programmer's Manual (3)
Updated: 2008-08-11
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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.

COLOPHON

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