randperm

来自「Calc Software Package for Number Calc」· 代码 · 共 74 行

NAME
    randperm - randomly permute a list or matrix

SYNOPSIS
    randperm(x)

TYPES
    x		list or matrix

    return	same as x

DESCRIPTION
    For a list or matrix x, randperm(x) returns a copy of x in which
    the elements have been randomly permuted.  The value of x is not
    changed.

    This function uses the rand() subtractive 100 shuffle pseudo-random
    number generator.

EXAMPLE
    ; A = list(1,2,2,3,4)
    ; randperm(A)

    list (5 elements, 5 nonzero):
	  [[0]] = 4
	  [[1]] = 1
	  [[2]] = 2
	  [[3]] = 3
	  [[4]] = 2

    ; randperm(A)

    list (5 elements, 5 nonzero):
	  [[0]] = 2
	  [[1]] = 1
	  [[2]] = 4
	  [[3]] = 2
	  [[4]] = 3

LIMITS
    none

LINK LIBRARY
    none

SEE ALSO
    comp, fact, rand, perm

## Copyright (C) 1999-2006  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.
## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
##
## @(#) $Revision: 29.4 $
## @(#) $Id: randperm,v 29.4 2006/06/25 22:16:55 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/randperm,v $
##
## Under source code control:	1995/07/10 02:09:31
## 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/