.\"	$OpenBSD: ctanh.3,v 1.1 2011/07/20 17:50:43 martynas Exp $
.\"
.\" Copyright (c) 2011 Martynas Venckus <martynas@openbsd.org>
.\"
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.Dd $Mdocdate: July 20 2011 $
.Dt CTANH 3
.Os
.Sh NAME
.Nm ctanh ,
.Nm ctanhf ,
.Nm ctanhl
.Nd complex hyperbolic tangent
.Sh SYNOPSIS
.Fd #include <complex.h>
.Ft double complex
.Fn ctanh "double complex z"
.Ft float complex
.Fn ctanhf "float complex z"
.Ft long double complex
.Fn ctanhl "long double complex z"
.Sh DESCRIPTION
The
.Fn ctanh ,
.Fn ctanhf
and
.Fn ctanhl
functions compute the complex hyperbolic tangent of
.Fa z .
.Pp
If
.Fa z
= x + iy, then
.Bd -literal -offset indent
ctanh(z) = (sinh(2x) + i sin(2y)) / (cosh(2x) + cos(2y)).
.Ed
.Sh RETURN VALUES
The
.Fn ctanh ,
.Fn ctanhf
and
.Fn ctanhl
functions return the complex hyperbolic tangent of
.Fa z .
.Sh SEE ALSO
.Xr ccosh 3 ,
.Xr csinh 3
.Sh STANDARDS
The
.Fn ctanh ,
.Fn ctanhf
and
.Fn ctanhl
functions conform to
.St -isoC-99 .