mirror of
https://github.com/lcn2/calc.git
synced 2025-08-16 01:03:29 +03:00
db77e29a23
Converted all ASCII tabs to ASCII spaces using a 8 character tab stop, for all files, except for all Makefiles (plus rpm.mk). The `git diff -w` reports no changes.
57 lines
1.7 KiB
Plaintext
57 lines
1.7 KiB
Plaintext
NAME
|
|
asech - inverse hyperbolic secant
|
|
|
|
SYNOPSIS
|
|
asech(x [,eps])
|
|
|
|
TYPES
|
|
x real, 0 < x <= 1
|
|
eps 0 < real < 1, defaults to epsilon()
|
|
|
|
return real
|
|
|
|
DESCRIPTION
|
|
Returns the asech of x to a multiple of eps with error less in
|
|
absolute value than .75 * eps.
|
|
|
|
asech(x) is the real number v for which sech(v) = x. It is given by
|
|
|
|
asech(x) = ln((1 + sqrt(1 - x^2))/x)
|
|
|
|
EXAMPLE
|
|
; print asech(.5,1e-5), asech(.5,1e-10), asech(.5,1e-15), asech(.5,1e-20)
|
|
1.31696 1.3169578969 1.316957896924817 1.31695789692481670862
|
|
|
|
LIMITS
|
|
0 < eps < 1
|
|
|
|
LINK LIBRARY
|
|
NUMBER *qasech(NUMBER *x, NUMBER *eps)
|
|
|
|
SEE ALSO
|
|
sinh, cosh, tanh, coth, sech, csch
|
|
asinh, acosh, atanh, acoth, acsch
|
|
epsilon
|
|
|
|
## Copyright (C) 1999,2023 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: 1995/11/13 03:49:00
|
|
## File existed as early as: 1995
|
|
##
|
|
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
|
|
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
|