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62 lines
1.9 KiB
Plaintext
62 lines
1.9 KiB
Plaintext
NAME
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ln - logarithm function
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SYNOPSIS
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ln(x [,eps])
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TYPES
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x nonzero real or complex
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eps nonzero real, defaults to epsilon()
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return real or complex
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DESCRIPTION
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Approximate the natural logarithm function of x by a multiple of
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epsilon, the error having absolute value less than 0.75 * eps.
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If n is a positive integer, ln(x, 10^-n) will usually be correct
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to the n-th decimal place.
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EXAMPLE
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; print ln(10, 1e-5), ln(10, 1e-10), ln(10, 1e-15), ln(10, 1e-20)
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2.30259 2.302585093 2.302585092994046 2.30258509299404568402
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; print ln(2+3i, 1e-5), ln(2+3i, 1e-10)
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1.28247+.98279i 1.2824746787+.9827937232i
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LIMITS
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x != 0
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eps > 0
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LINK LIBRARY
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NUMBER *qln(NUMBER *x, NUMBER *eps)
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COMPLEX *c_ln(COMPLEX *x, NUMBER *eps)
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SEE ALSO
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exp, acosh, asinh, atanh, log
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## Copyright (C) 1999 Landon Curt Noll
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##
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## Calc is open software; you can redistribute it and/or modify it under
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## the terms of the version 2.1 of the GNU Lesser General Public License
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## as published by the Free Software Foundation.
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##
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## Calc is distributed in the hope that it will be useful, but WITHOUT
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## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
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## Public License for more details.
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##
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## A copy of version 2.1 of the GNU Lesser General Public License is
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## distributed with calc under the filename COPYING-LGPL. You should have
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## received a copy with calc; if not, write to Free Software Foundation, Inc.
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## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
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##
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## @(#) $Revision: 29.5 $
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## @(#) $Id: ln,v 29.5 2006/05/07 13:05:18 chongo Exp $
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## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/ln,v $
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##
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## Under source code control: 1995/10/11 04:41:26
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## File existed as early as: 1995
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##
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## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
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## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
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