/population.c

  1/*
  2 * population.c -- Implementation of population management code.
  3 * $Id: population.c,v 1.5 2002/06/04 16:33:57 rwx Exp $
  4 */
  5/*
  6 * Copyright (C) 2002 Juan M. Bello Rivas <rwx@synnergy.net>
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License as published by
 10 * the Free Software Foundation; either version 2 of the License, or
 11 * (at your option) any later version.
 12 *
 13 * This program is distributed in the hope that it will be useful,
 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 * GNU General Public License for more details.
 17 *
 18 * You should have received a copy of the GNU General Public License
 19 * along with this program; if not, write to the Free Software
 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 21 */
 22
 23
 24#include "config.h"
 25
 26#ifdef STDC_HEADERS
 27# include <stdio.h>
 28# include <stdlib.h>
 29# include <string.h>
 30#endif /* STDC_HEADERS */
 31
 32#include <assert.h>
 33#include <sys/types.h>
 34
 35#include "chromosome.h"
 36#include "individual.h"
 37#include "individual-priv.h"
 38#include "population.h"
 39#include "population-priv.h"
 40
 41
 42struct population *
 43new_population(size_t len)
 44{
 45	struct population *p;
 46
 47	assert(len > 0);
 48
 49	p = calloc(1, sizeof(struct population));
 50	if (!p)
 51		return NULL;
 52
 53	p->len = len;
 54	p->pop = calloc(p->len, sizeof(struct individual *));
 55	if (!p->pop) {
 56		free(p);
 57		return NULL;
 58	}
 59
 60	return p;
 61}
 62
 63void
 64delete_population(struct population *self)
 65{
 66	size_t i;
 67
 68	assert(self);
 69
 70	if (self->pop)
 71		for (i = 0; i < self->len; i++)
 72			if (self->pop[i]) delete_individual(self->pop[i]);
 73	free(self->pop);
 74	free(self->select_data);
 75	free(self);
 76}
 77
 78
 79struct fitness_stats *
 80population_get_fitness_stats(struct population *self)
 81{
 82	assert(self);
 83
 84	return &self->stats;
 85}
 86
 87
 88struct individual *
 89population_get_fittest(struct population *self)
 90{
 91	assert(self);
 92
 93	qsort(self->pop, self->len, sizeof(struct individual *),
 94		(int (*)(const void *, const void *)) individual_compare);
 95
 96	return self->pop[0];
 97}
 98
 99
100void
101population_compute_fitness_stats(struct population *self)
102{
103	int i;
104	struct individual **pop;
105	struct fitness_stats *stats;
106
107	assert(self);
108
109	stats = &self->stats;
110	memset(stats, 0, sizeof(struct fitness_stats));
111
112	pop = self->pop;
113
114	/*
115	 * This function assumes the population array has been sorted in
116	 * advance (either by population_get_fittest or other means).
117	 */
118	stats->minimum = individual_get_fitness(pop[0]);
119	stats->maximum = individual_get_fitness(pop[self->len - 1]);
120
121	for (i = 0; i < self->len; i++)
122		stats->total += individual_get_fitness(pop[i]);
123
124	stats->average = stats->total / (double) self->len;
125}
126
127
128void
129population_print(struct population *self, FILE *fp)
130{
131	int i;
132
133        individual_print(population_get_fittest(self), stdout);
134	/* for (i = 0; i < self->len; i++) */
135	/* 	individual_print(self->pop[i], fp); */
136}