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 imag-
       inary part of y is chosen in the interval [-pi,pi].  The real part of y is chosen nonnegative.

       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 3.25 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)