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Some folks might think: “you still use RCS”?!? And we will say, hey, at least we switched from SCCS to RCS back in … I think it was around 1994 ... at least we are keeping up! :-) :-) :-) Logs say that SCCS version 18 became RCS version 19 on 1994 March 18. RCS served us well. But now it is time to move on. And so we are switching to git. Calc releases produce a lot of file changes. In the 125 releases of calc since 1996, when I started managing calc releases, there have been 15473 file mods!
65 lines
2.0 KiB
Plaintext
65 lines
2.0 KiB
Plaintext
NAME
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randbit - Blum-Blum-Shub pseudo-random number generator
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SYNOPSIS
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randombit([x])
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TYPES
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x integer
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return integer
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DESCRIPTION
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If x > 0, randombit(x) returns a pseudo-random integer in [0, 2^x),
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i.e. the same as rand(2^x). If the integer returned is
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b_1 * 2^(x-1) + b_2 * 2^(x-2) + ... + b_n,
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where each b_i is 0 or 1, then b_1, b_2, ..., b_n may be
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considered as a sequence of x random bits.
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If x <= 0, randombit(x) causes the random-number generator to skip
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abs(x) bits, and returns abs(x).
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If x is omitted, it is assumed to have the value of 1.
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See the random() help page for details on the additive 55 shuffle
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pseudo-random number generator.
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EXAMPLE
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; print srandom(0), randombit(20), randombit(20), randombit(20)
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RANDOM state 523139 567456 693508
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; print srandom(0), randombit(-20), randombit(20), randombit(-20)
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RANDOM state 20 567456 20
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LIMITS
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x != 0
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LINK LIBRARY
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void zrandom(long cnt, ZVALUE *res)
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SEE ALSO
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seed, srand, randbit, isrand, rand, srandom, israndom
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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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## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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##
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## Under source code control: 1997/02/17 01:18:22
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## File existed as early as: 1997
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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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