freebsd-nq/lib/msun/man/atanh.3
Jordan K. Hubbard 3a8617a83f J.T. Conklin's latest version of the Sun math library.
-- Begin comments from J.T. Conklin:
The most significant improvement is the addition of "float" versions
of the math functions that take float arguments, return floats, and do
all operations in floating point.  This doesn't help (performance)
much on the i386, but they are still nice to have.

The float versions were orginally done by Cygnus' Ian Taylor when
fdlibm was integrated into the libm we support for embedded systems.
I gave Ian a copy of my libm as a starting point since I had already
fixed a lot of bugs & problems in Sun's original code.  After he was
done, I cleaned it up a bit and integrated the changes back into my
libm.
-- End comments

Reviewed by:	jkh
Submitted by:	jtc
1994-08-19 09:40:01 +00:00

85 lines
2.7 KiB
Groff

.\" Copyright (c) 1985, 1991 Regents of the University of California.
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.\" from: @(#)atanh.3 5.2 (Berkeley) 5/6/91
.\" $Id: atanh.3,v 1.4 1993/10/29 22:57:24 jtc Exp $
.\"
.Dd May 6, 1991
.Dt ATANH 3
.Os BSD 4.3
.Sh NAME
.Nm atanh
.Nd inverse hyperbolic tangent function
.Sh SYNOPSIS
.Fd #include <math.h>
.Ft double
.Fn atanh "double x"
.Sh DESCRIPTION
The
.Fn atanh
function computes the inverse hyperbolic tangent
of the real
argument
.Ar x .
For a discussion of error due to roundoff, see
.Xr math 3 .
.Sh RETURN VALUES
The
.Fn atanh
function
returns the inverse hyperbolic tangent of
.Ar x
if successful.
On the
.Tn VAX
and
.Tn Tahoe ,
if the argument has absolute value
bigger than or equal to 1,
.Fn atanh
sets the global variable
.Va errno
to
.Er EDOM
and
a reserved operand fault is generated.
.Sh SEE ALSO
.Xr acosh 3 ,
.Xr asinh 3 ,
.Xr exp 3 ,
.Xr infnan 3 ,
.Xr math 3
.Sh HISTORY
The
.Fn atanh
function appeared in
.Bx 4.3 .