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75 lines
2.2 KiB
Plaintext
75 lines
2.2 KiB
Plaintext
NAME
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inverse - inverse of value
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SYNOPSIS
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inverse(x)
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TYPES
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If x is an object of type xx, the function xx_inv has to have
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been defined; any conditions on x and the nature of the returned
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value will depend on the definition of xx_inv.
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For non-object x:
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x nonzero number (real or complex) or nonsingular matrix
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return number or matrix
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DESCRIPTION
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For real or complex x, inverse(x) returns the value of 1/x.
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If x is a nonsingular n x n matrix and its elements are numbers or
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objects for which the required arithmetic operations are defined,
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inverse(x) returns the matrix m for which m * x = x * m = the unit
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n x n matrix. The inverse m will have the same index limits as x.
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EXAMPLE
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> print inverse(5/4), inverse(-2/7), inverse(3 + 4i)
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.8 -3.5 .12-.16i
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> mat A[2,2] = {2,3,5,7}
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> print inverse(A)
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mat [2,2] (4 elements, 4 nonzero):
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[0,0] = -7
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[0,1] = 3
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[1,0] = 5
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[1,1] = -2
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LIMITS
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none
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LINK LIBRARY
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void invertvalue(VALUE *x, VALUE *vres)
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NUMBER *qinv(NUMBER *x)
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COMPLEX *c_inv(COMPLEX *x)
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MATRIX *matinv(MATRIX *x)
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SEE ALSO
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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: 29.3 $
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## @(#) $Id: inverse,v 29.3 2005/10/18 10:48:29 chongo Exp $
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## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/inverse,v $
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##
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## Under source code control: 1996/03/12 23:10:01
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## File existed as early as: 1996
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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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