CACOSH(3) Linux Programmer s Manual CACOSH(3)

NAME cacosh, cacoshf, cacoshl - complex arc hyperbolic cosine

SYNOPSIS #include <complex.h>

double complex cacosh(double complex z); float complex cacoshf(float complex z); long double complex cacoshl(long double complex z);

Link with -lm.

DESCRIPTION The cacosh() function calculates the complex arc hyperpolic cosine of z. If y = cacosh(z), then z = ccosh(y). The imaginary part of y is chosen in the interval [-pi,pi]. The real part of y is chosen non-neg- ative.

One has:

cacosh(z) = (0.5) * clog((1 + z) / (1 - z))

VERSIONS These functions first appeared in glibc in version 2.1.

CONFORMING TO C99.

SEE ALSO acosh(3), cabs(3), cimag(3), complex(7)

COLOPHON This page is part of release 3.22 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/.

2008-08-11 CACOSH(3)