3a559a3b3c
------------------------------------------------------------------------ r1601 | sears.russell@gmail.com | 2012-03-20 18:43:00 -0400 (Tue, 20 Mar 2012) | 1 line commit bLSM bloom filter to stasis/util, which is where it really belongs ------------------------------------------------------------------------ r1600 | sears.russell@gmail.com | 2012-03-04 01:58:38 -0500 (Sun, 04 Mar 2012) | 1 line fix memory leak in skiplist unit test (now it is valgrind clean) ------------------------------------------------------------------------ r1599 | sears.russell@gmail.com | 2012-03-04 01:58:05 -0500 (Sun, 04 Mar 2012) | 1 line fix typo in finalize type ------------------------------------------------------------------------ r1598 | sears.russell@gmail.com | 2012-03-04 00:59:59 -0500 (Sun, 04 Mar 2012) | 1 line add comparator and finalizer parameters to skiplist constructor ------------------------------------------------------------------------ r1597 | sears.russell@gmail.com | 2012-03-03 18:23:16 -0500 (Sat, 03 Mar 2012) | 1 line bugfixes for skiplist ------------------------------------------------------------------------ r1596 | sears.russell@gmail.com | 2012-03-02 15:05:07 -0500 (Fri, 02 Mar 2012) | 1 line updated concurrentSkipList. Seeing strange crashes ------------------------------------------------------------------------ r1595 | sears.russell@gmail.com | 2012-03-01 16:51:59 -0500 (Thu, 01 Mar 2012) | 1 line add progress reports ------------------------------------------------------------------------ r1594 | sears.russell@gmail.com | 2012-02-28 13:17:05 -0500 (Tue, 28 Feb 2012) | 1 line experimental support for automatic logfile preallocation ------------------------------------------------------------------------ r1593 | sears.russell@gmail.com | 2012-02-28 12:10:01 -0500 (Tue, 28 Feb 2012) | 1 line add histogram reporting to rawIOPS benchmark ------------------------------------------------------------------------ r1592 | sears.russell@gmail.com | 2012-02-24 16:31:36 -0500 (Fri, 24 Feb 2012) | 1 line userspace raid 0 implementation ------------------------------------------------------------------------ r1591 | sears.russell@gmail.com | 2012-02-12 01:47:25 -0500 (Sun, 12 Feb 2012) | 1 line add skiplist unit test, fix compile warnings ------------------------------------------------------------------------ r1590 | sears.russell@gmail.com | 2012-02-12 00:52:52 -0500 (Sun, 12 Feb 2012) | 1 line fix compile error ------------------------------------------------------------------------ r1589 | sears.russell@gmail.com | 2012-02-12 00:50:21 -0500 (Sun, 12 Feb 2012) | 1 line fix some bugs in hazard.h surrounding thread list management and overruns of R under high contention ------------------------------------------------------------------------ r1588 | sears.russell@gmail.com | 2012-02-11 14:23:10 -0500 (Sat, 11 Feb 2012) | 1 line add hazard pointer for get_lock. It was implicitly blowing away the hazard pointer protecting y in the caller ------------------------------------------------------------------------ r1587 | sears.russell@gmail.com | 2012-02-10 18:51:25 -0500 (Fri, 10 Feb 2012) | 1 line fix null pointer bug ------------------------------------------------------------------------ r1586 | sears.russell@gmail.com | 2012-02-10 18:03:39 -0500 (Fri, 10 Feb 2012) | 1 line add simple refcounting scheme to concurrentSkipList. This solves the problem where a deleted node points to another deleted node, and we only have a hazard pointer for the first node. ------------------------------------------------------------------------ r1585 | sears.russell@gmail.com | 2012-02-10 14:19:14 -0500 (Fri, 10 Feb 2012) | 1 line add hazard pointers for update using the smallest free slot first. The old method left a race condition, since hazard_scan stops at the first null pointer. ------------------------------------------------------------------------ r1584 | sears.russell@gmail.com | 2012-02-10 02:45:30 -0500 (Fri, 10 Feb 2012) | 1 line add hazard pointers for update array ------------------------------------------------------------------------ r1583 | sears.russell@gmail.com | 2012-02-10 00:04:50 -0500 (Fri, 10 Feb 2012) | 1 line skiplist update: concurrent, but broken ------------------------------------------------------------------------ r1582 | sears.russell@gmail.com | 2012-02-09 17:44:27 -0500 (Thu, 09 Feb 2012) | 1 line skip list implementation. Not concurrent yet. ------------------------------------------------------------------------ r1581 | sears.russell@gmail.com | 2012-02-08 13:33:29 -0500 (Wed, 08 Feb 2012) | 1 line Commit of a bunch of new, unused code: KISS random number generator, Hazard Pointers, SUX latches (untested) and bit twiddling for concurrent b-tree ------------------------------------------------------------------------ r1580 | sears.russell@gmail.com | 2012-01-17 19:17:37 -0500 (Tue, 17 Jan 2012) | 1 line fix typo ------------------------------------------------------------------------ r1579 | sears.russell@gmail.com | 2012-01-11 18:33:31 -0500 (Wed, 11 Jan 2012) | 1 line static build fixes for linux. hopefully these do not break macos... ------------------------------------------------------------------------ r1578 | sears.russell@gmail.com | 2012-01-09 19:13:34 -0500 (Mon, 09 Jan 2012) | 1 line fix cmake under linux ------------------------------------------------------------------------ r1577 | sears.russell@gmail.com | 2012-01-09 18:37:15 -0500 (Mon, 09 Jan 2012) | 1 line fix linux static binary compilation bugs ------------------------------------------------------------------------ r1576 | sears.russell | 2012-01-09 18:00:08 -0500 (Mon, 09 Jan 2012) | 1 line port to macos x ------------------------------------------------------------------------ r1575 | sears.russell | 2012-01-09 17:39:43 -0500 (Mon, 09 Jan 2012) | 1 line add missing _ from sync call name ------------------------------------------------------------------------ r1574 | sears.russell@gmail.com | 2012-01-09 14:26:31 -0500 (Mon, 09 Jan 2012) | 1 line add -rt flag to static builds ------------------------------------------------------------------------ r1573 | sears.russell@gmail.com | 2011-12-20 23:38:29 -0500 (Tue, 20 Dec 2011) | 1 line Simple makefile geared toward building libstasis.so and libstasis.a (and nothing else) ------------------------------------------------------------------------ r1572 | sears.russell@gmail.com | 2011-12-20 22:37:54 -0500 (Tue, 20 Dec 2011) | 1 line add some missing #include<config.h> lines
409 lines
17 KiB
C
409 lines
17 KiB
C
/*
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* check_kiss.c
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*
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* Created on: Feb 8, 2012
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* Author: sears
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*/
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/*---
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This software is copyrighted by the Regents of the University of
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California, and other parties. The following terms apply to all files
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associated with the software unless explicitly disclaimed in
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individual files.
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The authors hereby grant permission to use, copy, modify, distribute,
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and license this software and its documentation for any purpose,
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provided that existing copyright notices are retained in all copies
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and that this notice is included verbatim in any distributions. No
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written agreement, license, or royalty fee is required for any of the
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authorized uses. Modifications to this software may be copyrighted by
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their authors and need not follow the licensing terms described here,
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provided that the new terms are clearly indicated on the first page of
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each file where they apply.
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IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
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FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
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DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
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INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
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NON-INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND
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THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
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MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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GOVERNMENT USE: If you are acquiring this software on behalf of the
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U.S. government, the Government shall have only "Restricted Rights" in
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the software and related documentation as defined in the Federal
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Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you are
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acquiring the software on behalf of the Department of Defense, the
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software shall be classified as "Commercial Computer Software" and the
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Government shall have only "Restricted Rights" as defined in Clause
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252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
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authors grant the U.S. Government and others acting in its behalf
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permission to use and distribute the software in accordance with the
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terms specified in this license.
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---*/
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#include "../check_includes.h"
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#include <stasis/constants.h>
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#include <stasis/util/random.h>
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#include <sys/time.h>
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#include <time.h>
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#include <assert.h>
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#define LOG_NAME "check_lhtable.log"
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/**
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@test
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*/
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START_TEST(kiss_smokeTest) {
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int i; uint32_t k;
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kiss_table_t kiss;
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stasis_util_random_kiss_settable(&kiss, 12345,65435,34221,12345,9983651,95746118);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_LFIB4(&kiss);} printf("%u\n", k-1064612766U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_SWB (&kiss);} printf("%u\n", k- 627749721U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_KISS (&kiss);} printf("%u\n", k-1372460312U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_CONG (&kiss);} printf("%u\n", k-1529210297U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_SHR3 (&kiss);} printf("%u\n", k-2642725982U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_MWC (&kiss);} printf("%u\n", k- 904977562U);
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for(i=1;i<1000001;i++){k=stasis_util_random_kiss_FIB (&kiss);} printf("%u\n", k-3519793928U);
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} END_TEST
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Suite * check_suite(void) {
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Suite *s = suite_create("hazard");
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/* Begin a new test */
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TCase *tc = tcase_create("hazard");
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tcase_set_timeout(tc, 0); // disable timeouts
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/* Sub tests are added, one per line, here */
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// XXX this test might be flawed.
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tcase_add_test(tc, kiss_smokeTest);
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/* --------------------------------------------- */
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tcase_add_checked_fixture(tc, setup, teardown);
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suite_add_tcase(s, tc);
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return s;
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}
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#include "../check_setup.h"
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#if 0
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/* RCS: Note, the unmodified code no longer works. It assumes longs are 32-bit
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* Change the UL macro to "unsigned int" to get it to pass tests.
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*/
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/*
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Subject: Random numbers for C: The END?
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Date: Wed, 20 Jan 1999 10:55:14 -0500
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From: George Marsaglia <geo@stat.fsu.edu>
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Message-ID: <36A5FC62.17C9CC33@stat.fsu.edu>
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Newsgroups: sci.stat.math,sci.math
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Lines: 301
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My offer of RNG's for C was an invitation to dance;
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I did not expect the Tarantella. I hope this post will
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stop the music, or at least slow it to a stately dance
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for language chauvinists and software police---under
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a different heading.
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In response to a number of requests for good RNG's in
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C, and mindful of the desirability of having a variety
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of methods readily available, I offered several. They
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were implemented as in-line functions using the #define
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feature of C.
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Numerous responses have led to improvements; the result
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is the listing below, with comments describing the
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generators.
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I thank all the experts who contributed suggestions, either
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directly to me or as part of the numerous threads.
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It seems necessary to use a (circular) table in order
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to get extremely long periods for some RNG's. Each new
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number is some combination of the previous r numbers, kept
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in the circular table. The circular table has to keep
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at least the last r, but possible more than r, numbers.
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For speed, an 8-bit index seems best for accessing
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members of the table---at least for Fortran, where an
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8-bit integer is readily available via integer*1, and
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arithmetic on the index is automatically mod 256
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(least-absolute-residue).
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Having little experience with C, I got out my little
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(but BIG) Kernighan and Ritchie book to see if there
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were an 8-bit integer type. I found none, but I did
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find char and unsigned char: one byte. Furthemore, K&R
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said arithmetic on characters was ok. That, and a study
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of the #define examples, led me to propose #define's
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for in-line generators LFIB4 and SWB, with monster
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periods. But it turned out that char arithmetic jumps
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"out of character", other than for simple cases such as
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c++ or c+=1. So, for safety, the index arithmetic
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below is kept in character by the UC definition.
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Another improvement on the original version takes
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advantage of the comma operator, which, to my chagrin,
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I had not seen in K&R. It is there, but only with an
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example of (expression,expression). From the advice of
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contributors, I found that the comma operator allows
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(expression,...,expression,expression) with the
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last expression determining the value. That makes it
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much easier to create in-line functions via #define
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(see SHR3, LFIB4, SWB and FIB below).
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The improved #define's are listed below, with a
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function to initialize the table and a main program
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that calls each of the in-line functions one million
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times and then compares the result to what I got with
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a DOS version of gcc. That main program can serve
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as a test to see if your system produces the same
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results as mine.
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_________________________________________
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|If you run the program below, your output|
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| should be seven lines, each a 0 (zero).|
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-----------------------------------------
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Some readers of the threads are not much interested
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in the philosophical aspects of computer languages,
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but want to know: what is the use of this stuff?
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Here are simple examples of the use of the in-line
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functions: Include the #define's in your program, with
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the accompanying static variable declarations, and a
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procedure, such as the example, for initializing
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the static variable (seeds) and the table.
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Then any one of those in-line functions, inserted
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in a C expression, will provide a random 32-bit
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integer, or a random float if UNI or VNI is used.
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For example, KISS&255; would provide a random byte,
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while 5.+2.*UNI; would provide a random real (float)
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from 5 to 7. Or 1+MWC%10; would provide the
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proverbial "take a number from 1 to 10",
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(but with not quite, but virtually, equal
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probabilities).
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More generally, something such as 1+KISS%n; would
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provide a practical uniform random choice from 1 to n,
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if n is not too big.
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A key point is: a wide variety of very fast, high-
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quality, easy-to-use RNG's are available by means of
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the nine in-line functions below, used individually or
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in combination.
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The comments after the main test program describe the
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generators. These descriptions are much as in the first
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post, for those who missed them. Some of the
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generators (KISS, MWC, LFIB4) seem to pass all tests of
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randomness, particularly the DIEHARD battery of tests,
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and combining virtually any two or more of them should
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provide fast, reliable, long period generators. (CONG
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or FIB alone and CONG+FIB are suspect, but quite useful
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in combinations.)
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Serious users of random numbers may want to
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run their simulations with several different
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generators, to see if they get consistent results.
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These #define's may make it easy to do.
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Bonne chance,
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George Marsaglia
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The C code follows---------------------------------:
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*/
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#include <stdio.h>
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#define znew (z=36969*(z&65535)+(z>>16))
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#define wnew (w=18000*(w&65535)+(w>>16))
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#define MWC ((znew<<16)+wnew )
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#define SHR3 (jsr^=(jsr<<17), jsr^=(jsr>>13), jsr^=(jsr<<5))
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#define CONG (jcong=69069*jcong+1234567)
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#define FIB ((b=a+b),(a=b-a))
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#define KISS ((MWC^CONG)+SHR3)
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#define LFIB4 (c++,t[c]=t[c]+t[UC(c+58)]+t[UC(c+119)]+t[UC(c+178)])
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#define SWB (c++,bro=(x<y),t[c]=(x=t[UC(c+34)])-(y=t[UC(c+19)]+bro))
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#define UNI (KISS*2.328306e-10)
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#define VNI ((long) KISS)*4.656613e-10
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#define UC (unsigned char) /*a cast operation*/
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typedef unsigned long UL;
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/* Global static variables: */
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static UL z=362436069, w=521288629, jsr=123456789, jcong=380116160;
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static UL a=224466889, b=7584631, t[256];
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/* Use random seeds to reset z,w,jsr,jcong,a,b, and the table t[256]*/
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static UL x=0,y=0,bro; static unsigned char c=0;
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/* Example procedure to set the table, using KISS: */
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void settable(UL i1,UL i2,UL i3,UL i4,UL i5, UL i6)
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{ int i; z=i1;w=i2,jsr=i3; jcong=i4; a=i5; b=i6;
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for(i=0;i<256;i=i+1) t[i]=KISS;
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}
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/* This is a test main program. It should compile and print 7 0's. */
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int main(void){
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int i; UL k;
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settable(12345,65435,34221,12345,9983651,95746118);
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for(i=1;i<1000001;i++){k=LFIB4;} printf("%u\n", k-1064612766U);
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for(i=1;i<1000001;i++){k=SWB ;} printf("%u\n", k- 627749721U);
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for(i=1;i<1000001;i++){k=KISS ;} printf("%u\n", k-1372460312U);
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for(i=1;i<1000001;i++){k=CONG ;} printf("%u\n", k-1529210297U);
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for(i=1;i<1000001;i++){k=SHR3 ;} printf("%u\n", k-2642725982U);
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for(i=1;i<1000001;i++){k=MWC ;} printf("%u\n", k- 904977562U);
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for(i=1;i<1000001;i++){k=FIB ;} printf("%u\n", k-3519793928U);
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}
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/*-----------------------------------------------------
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Write your own calling program and try one or more of
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the above, singly or in combination, when you run a
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simulation. You may want to change the simple 1-letter
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names, to avoid conflict with your own choices. */
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/* All that follows is comment, mostly from the initial
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post. You may want to remove it */
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/* Any one of KISS, MWC, FIB, LFIB4, SWB, SHR3, or CONG
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can be used in an expression to provide a random 32-bit
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integer.
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The KISS generator, (Keep It Simple Stupid), is
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designed to combine the two multiply-with-carry
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generators in MWC with the 3-shift register SHR3 and
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the congruential generator CONG, using addition and
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exclusive-or. Period about 2^123.
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It is one of my favorite generators.
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The MWC generator concatenates two 16-bit multiply-
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with-carry generators, x(n)=36969x(n-1)+carry,
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y(n)=18000y(n-1)+carry mod 2^16, has period about
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2^60 and seems to pass all tests of randomness. A
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favorite stand-alone generator---faster than KISS,
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which contains it.
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FIB is the classical Fibonacci sequence
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x(n)=x(n-1)+x(n-2),but taken modulo 2^32.
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Its period is 3*2^31 if one of its two seeds is odd
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and not 1 mod 8. It has little worth as a RNG by
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itself, but provides a simple and fast component for
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use in combination generators.
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SHR3 is a 3-shift-register generator with period
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2^32-1. It uses y(n)=y(n-1)(I+L^17)(I+R^13)(I+L^5),
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with the y's viewed as binary vectors, L the 32x32
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binary matrix that shifts a vector left 1, and R its
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transpose. SHR3 seems to pass all except those
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related to the binary rank test, since 32 successive
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values, as binary vectors, must be linearly
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independent, while 32 successive truly random 32-bit
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integers, viewed as binary vectors, will be linearly
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independent only about 29% of the time.
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CONG is a congruential generator with the widely used 69069
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multiplier: x(n)=69069x(n-1)+1234567. It has period
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2^32. The leading half of its 32 bits seem to pass
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tests, but bits in the last half are too regular.
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LFIB4 is an extension of what I have previously
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defined as a lagged Fibonacci generator:
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x(n)=x(n-r) op x(n-s), with the x's in a finite
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set over which there is a binary operation op, such
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as +,- on integers mod 2^32, * on odd such integers,
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exclusive-or(xor) on binary vectors. Except for
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those using multiplication, lagged Fibonacci
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generators fail various tests of randomness, unless
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the lags are very long. (See SWB below).
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To see if more than two lags would serve to overcome
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the problems of 2-lag generators using +,- or xor, I
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have developed the 4-lag generator LFIB4 using
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addition: x(n)=x(n-256)+x(n-179)+x(n-119)+x(n-55)
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mod 2^32. Its period is 2^31*(2^256-1), about 2^287,
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and it seems to pass all tests---in particular,
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those of the kind for which 2-lag generators using
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+,-,xor seem to fail. For even more confidence in
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its suitability, LFIB4 can be combined with KISS,
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with a resulting period of about 2^410: just use
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(KISS+LFIB4) in any C expression.
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SWB is a subtract-with-borrow generator that I
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developed to give a simple method for producing
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extremely long periods:
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x(n)=x(n-222)-x(n-237)- borrow mod 2^32.
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The 'borrow' is 0, or set to 1 if computing x(n-1)
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caused overflow in 32-bit integer arithmetic. This
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generator has a very long period, 2^7098(2^480-1),
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about 2^7578. It seems to pass all tests of
|
|
randomness, except for the Birthday Spacings test,
|
|
which it fails badly, as do all lagged Fibonacci
|
|
generators using +,- or xor. I would suggest
|
|
combining SWB with KISS, MWC, SHR3, or CONG.
|
|
KISS+SWB has period >2^7700 and is highly
|
|
recommended.
|
|
Subtract-with-borrow has the same local behaviour
|
|
as lagged Fibonacci using +,-,xor---the borrow
|
|
merely provides a much longer period.
|
|
SWB fails the birthday spacings test, as do all
|
|
lagged Fibonacci and other generators that merely
|
|
combine two previous values by means of =,- or xor.
|
|
Those failures are for a particular case: m=512
|
|
birthdays in a year of n=2^24 days. There are
|
|
choices of m and n for which lags >1000 will also
|
|
fail the test. A reasonable precaution is to always
|
|
combine a 2-lag Fibonacci or SWB generator with
|
|
another kind of generator, unless the generator uses
|
|
*, for which a very satisfactory sequence of odd
|
|
32-bit integers results.
|
|
|
|
The classical Fibonacci sequence mod 2^32 from FIB
|
|
fails several tests. It is not suitable for use by
|
|
itself, but is quite suitable for combining with
|
|
other generators.
|
|
|
|
The last half of the bits of CONG are too regular,
|
|
and it fails tests for which those bits play a
|
|
significant role. CONG+FIB will also have too much
|
|
regularity in trailing bits, as each does. But keep
|
|
in mind that it is a rare application for which
|
|
the trailing bits play a significant role. CONG
|
|
is one of the most widely used generators of the
|
|
last 30 years, as it was the system generator for
|
|
VAX and was incorporated in several popular
|
|
software packages, all seemingly without complaint.
|
|
|
|
Finally, because many simulations call for uniform
|
|
random variables in 0<x<1 or -1<x<1, I use #define
|
|
statements that permit inclusion of such variates
|
|
directly in expressions: using UNI will provide a
|
|
uniform random real (float) in (0,1), while VNI will
|
|
provide one in (-1,1).
|
|
|
|
All of these: MWC, SHR3, CONG, KISS, LFIB4, SWB, FIB
|
|
UNI and VNI, permit direct insertion of the desired
|
|
random quantity into an expression, avoiding the
|
|
time and space costs of a function call. I call
|
|
these in-line-define functions. To use them, static
|
|
variables z,w,jsr,jcong,a and b should be assigned
|
|
seed values other than their initial values. If
|
|
LFIB4 or SWB are used, the static table t[256] must
|
|
be initialized.
|
|
|
|
A note on timing: It is difficult to provide exact
|
|
time costs for inclusion of one of these in-line-
|
|
define functions in an expression. Times may differ
|
|
widely for different compilers, as the C operations
|
|
may be deeply nested and tricky. I suggest these
|
|
rough comparisons, based on averaging ten runs of a
|
|
routine that is essentially a long loop:
|
|
for(i=1;i<10000000;i++) L=KISS; then with KISS
|
|
replaced with SHR3, CONG,... or KISS+SWB, etc. The
|
|
times on my home PC, a Pentium 300MHz, in nanoseconds:
|
|
FIB 49;LFIB4 77;SWB 80;CONG 80;SHR3 84;MWC 93;KISS 157;
|
|
VNI 417;UNI 450;
|
|
*/
|
|
#endif
|