.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
.\"
.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
.\" Distributed under GPL
.\" %%%LICENSE_END
.\"
.TH CASINH 3 2015-04-19 "" "Linux Programmer's Manual"
.SH NAME
casinh, casinhf, casinhl \- complex arc sine hyperbolic
.SH SYNOPSIS
.B #include <complex.h>
.PP
.BI "double complex casinh(double complex " z );
.br
.BI "float complex casinhf(float complex " z );
.br
.BI "long double complex casinhl(long double complex " z );
.PP
Link with \fI\-lm\fP.
.SH DESCRIPTION
These functions calculate the complex arc hyperbolic sine of
.IR z .
If \fIy\ =\ casinh(z)\fP, then \fIz\ =\ csinh(y)\fP.
The imaginary part of
.I y
is chosen in the interval [\-pi/2,pi/2].
.PP
One has:
.PP
.nf
    casinh(z) = clog(z + csqrt(z * z + 1))
.fi
.SH VERSIONS
These functions first appeared in glibc in version 2.1.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbw30 lb lb
l l l.
Interface	Attribute	Value
T{
.BR casinh (),
.BR casinhf (),
.BR casinhl ()
T}	Thread safety	MT-Safe
.TE
.SH CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.
.SH SEE ALSO
.BR asinh (3),
.BR cabs (3),
.BR cimag (3),
.BR csinh (3),
.BR complex (7)
.SH COLOPHON
This page is part of release 4.15 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%https://www.kernel.org/doc/man\-pages/.