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calc/help/randbit
Landon Curt Noll a31078bbec Remove all RCS @(#) lines and RCS strings
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!
2017-05-23 01:33:23 -07:00

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NAME
randbit - additive 55 shuffle pseudo-random number generator
SYNOPSIS
randbit([x])
TYPES
x integer
return integer
DESCRIPTION
If x > 0, randbit(x) returns a pseudo-random integer in [0, 2^x),
i.e. the same as rand(2^x). If the integer returned is
b_1 * 2^(x-1) + b_2 * 2^(x-2) + ... + b_n,
where each b_i is 0 or 1, then b_1, b_2, ..., b_n may be
considered as a sequence of x random bits.
If x <= 0, randbit(x) causes the random-number generator to skip
abs(x) bits, and returns abs(x).
If x is omitted, it is assumed to have the value of 1.
See the rand() help page for details on the additive 55 shuffle
pseudo-random number generator.
EXAMPLE
; print srand(0), randbit(20), randbit(20), randbit(20), randbit(20)
RAND state 817647 476130 944201 822573
; print srand(0), randbit(-20), randbit(20), randbit(-20), randbit(20)
RAND state 20 476130 20 822573
LIMITS
x != 0
LINK LIBRARY
void zrand(long cnt, ZVALUE *res)
SEE ALSO
seed, srand, randbit, isrand, random, srandom, israndom
## Copyright (C) 1999 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: 1996/01/01 03:17:22
## File existed as early as: 1996
##
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/