mirror of
https://github.com/lcn2/calc.git
synced 2025-08-19 01:13:27 +03:00
55 lines
1.6 KiB
Plaintext
55 lines
1.6 KiB
Plaintext
NAME
|
|
atanh - inverse hyperbolic tangent
|
|
|
|
SYNOPSIS
|
|
atanh(x [,eps])
|
|
|
|
TYPES
|
|
x real
|
|
eps nonzero real, defaults to epsilon()
|
|
|
|
return real
|
|
|
|
DESCRIPTION
|
|
Returns the atanh of x to a multiple of eps with error less in
|
|
absolute value than .75 * eps.
|
|
|
|
atanh(x) is the real number v for which tanh(v) = x. It is given by
|
|
|
|
atanh(x) = ln((1 + x)/(1 - x))/2
|
|
|
|
EXAMPLE
|
|
; print atanh(.5,1e-5), atanh(.5,1e-10), atanh(.5,1e-15), atanh(.5,1e-20)
|
|
0.54931 0.5493061443 0.549306144334055 0.5493061443340548457
|
|
|
|
LIMITS
|
|
none
|
|
|
|
LINK LIBRARY
|
|
NUMBER *qatanh(NUMBER *x, NUMBER *eps)
|
|
|
|
SEE ALSO
|
|
asinh, acosh, asech, acsch, acoth, epsilon
|
|
|
|
## Copyright (C) 1999,2021 Landon Curt Noll
|
|
##
|
|
## Calc is open software; you can redistribute it and/or modify it under
|
|
## the terms of the version 2.1 of the GNU Lesser General Public License
|
|
## as published by the Free Software Foundation.
|
|
##
|
|
## Calc is distributed in the hope that it will be useful, but WITHOUT
|
|
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
|
|
## Public License for more details.
|
|
##
|
|
## A copy of version 2.1 of the GNU Lesser General Public License is
|
|
## distributed with calc under the filename COPYING-LGPL. You should have
|
|
## received a copy with calc; if not, write to Free Software Foundation, Inc.
|
|
## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
##
|
|
## Under source code control: 1994/03/19 01:40:27
|
|
## File existed as early as: 1994
|
|
##
|
|
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
|
|
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
|