46 lines
946 B
C
46 lines
946 B
C
#if !defined( lint ) && !defined( SABER )
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static const char sccsid[] = "@(#)random.c 4.10 98/04/23 xlockmore";
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#endif
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/*-
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* random.c - various utilities for random numbers
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*
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* Copyright (c) 1998 by David Bagley
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*
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* Revision History:
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*
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* Changes maintained by David Bagley <bagleyd@tux.org>
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* 23-Apr-96: Separated out of util.c
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*
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*/
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/*-
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* Dr. Park's algorithm published in the Oct. '88 ACM "Random Number
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* Generators: Good Ones Are Hard To Find" His version available at
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* ftp://cs.wm.edu/pub/rngs.tar Present form by many authors.
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*/
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static int Seed = 1; /* This is required to be 32 bits long */
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/*-
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* Given an integer, this routine initializes the RNG seed.
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*/
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void
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SetRNG(long int s)
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{
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Seed = (int) s;
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}
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/*-
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* Returns an integer between 0 and 2147483647, inclusive.
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*/
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long
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LongRNG(void)
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{
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if ((Seed = Seed % 44488 * 48271 - Seed / 44488 * 3399) < 0)
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Seed += 2147483647;
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return (long) (Seed - 1);
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}
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