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Merge in GEQO Optimizer

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From: "Martin S. Utesch" <utesch@aut.tu-freiberg.de>
This commit is contained in:
Marc G. Fournier
1997-02-19 12:59:07 +00:00
parent 34f35a4c19
commit 29138eeb3c
29 changed files with 3823 additions and 3 deletions
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76
src/backend/optimizer/geqo/geqo_mutation.c Normal file
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/*------------------------------------------------------------------------
*
* geqo_mutation.c--
*
* TSP mutation routines
*
* $Id: geqo_mutation.c,v 1.1 1997/02/19 12:57:13 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
/* contributed by:
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
* Martin Utesch * Institute of Automatic Control *
= = University of Mining and Technology =
* utesch@aut.tu-freiberg.de * Freiberg, Germany *
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
*/
/* this is adopted from Genitor : */
/*************************************************************/
/* */
/* Copyright (c) 1990 */
/* Darrell L. Whitley */
/* Computer Science Department */
/* Colorado State University */
/* */
/* Permission is hereby granted to copy all or any part of */
/* this program for free distribution. The author's name */
/* and this copyright notice must be included in any copy. */
/* */
/*************************************************************/
#include "postgres.h"
#include "nodes/pg_list.h"
#include "nodes/relation.h"
#include "nodes/primnodes.h"
#include "utils/palloc.h"
#include "utils/elog.h"
#include "optimizer/internal.h"
#include "optimizer/paths.h"
#include "optimizer/pathnode.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/geqo_gene.h"
#include "optimizer/geqo_random.h"
#include "optimizer/geqo_mutation.h"
void
geqo_mutation (Gene *tour, int num_gene)
{
int swap1;
int swap2;
int num_swaps = geqo_randint (num_gene/3, 0);
Gene temp;
while (num_swaps > 0) {
swap1 = geqo_randint (num_gene-1, 0);
swap2 = geqo_randint (num_gene-1, 0);
while (swap1 == swap2)
swap2 = geqo_randint (num_gene-1, 0);
temp = tour[swap1];
tour[swap1] = tour[swap2];
tour[swap2] = temp;
num_swaps -= 1;
}
}