2 * libsortnetwork - src/sn-markov.c
3 * Copyright (C) 2008-2010 Florian octo Forster
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; only version 2 of the License is applicable.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Florian octo Forster <ff at octo.it>
22 #ifndef _ISOC99_SOURCE
23 # define _ISOC99_SOURCE
25 #ifndef _POSIX_C_SOURCE
26 # define _POSIX_C_SOURCE 200809L
29 # define _XOPEN_SOURCE 700
44 #include "sn_network.h"
45 #include "sn_random.h"
47 #if !defined(__GNUC__) || !__GNUC__
48 # define __attribute__(x) /**/
51 static int inputs_num = 16;
53 static char *initial_input_file = NULL;
54 static char *best_output_file = NULL;
56 static sn_network_t *best_solution = NULL;
57 static int best_rating = INT_MAX;
59 static _Bool do_loop = 1;
60 static uint64_t max_iterations = 0;
62 static void sigint_handler (int signal __attribute__((unused)))
65 } /* void sigint_handler */
67 static void exit_usage (const char *name, int status)
69 printf ("Usage: %s [options]\n"
71 "Valid options are:\n"
72 " -i <file> Initial input file (REQUIRED)\n"
73 " -o <file> Write the current best solution to <file>\n"
74 " -n <number> Maximum number of steps (iterations) to perform\n"
75 " -h Display usage information (this message)\n"
79 } /* void exit_usage */
81 int read_options (int argc, char **argv)
85 while ((option = getopt (argc, argv, "i:o:n:h")) != -1)
91 if (initial_input_file != NULL)
92 free (initial_input_file);
93 initial_input_file = strdup (optarg);
99 if (best_output_file != NULL)
100 free (best_output_file);
101 best_output_file = strdup (optarg);
108 max_iterations = (uint64_t) strtoull (optarg,
113 fprintf (stderr, "Parsing integer argument failed: %s\n",
115 exit_usage (argv[0], EXIT_FAILURE);
122 exit_usage (argv[0], EXIT_SUCCESS);
127 } /* int read_options */
129 static int rate_network (const sn_network_t *n)
133 rate = SN_NETWORK_STAGE_NUM (n) * SN_NETWORK_INPUT_NUM (n);
134 rate += sn_network_get_comparator_num (n);
137 } /* int rate_network */
139 static sn_network_t *get_next (sn_network_t *n)
142 sn_network_t *nright;
148 nleft = sn_network_clone (n);
149 nright = sn_network_clone (n);
151 assert (nleft != NULL);
152 assert (nright != NULL);
154 /* combine the two parents */
155 nret = sn_network_combine (nleft, nright);
157 sn_network_destroy (nleft);
158 sn_network_destroy (nright);
160 /* randomly chose an input and do a min- or max-cut. */
161 while (SN_NETWORK_INPUT_NUM (nret) > inputs_num)
164 enum sn_network_cut_dir_e dir;
166 pos = sn_bounded_random (0, SN_NETWORK_INPUT_NUM (nret) - 1);
167 dir = (sn_bounded_random (0, 1) == 0) ? DIR_MIN : DIR_MAX;
169 assert ((pos >= 0) && (pos < SN_NETWORK_INPUT_NUM (nret)));
171 sn_network_cut_at (nret, pos, dir);
174 /* compress the network to get a compact representation */
175 sn_network_compress (nret);
177 assert (SN_NETWORK_INPUT_NUM (nret) == inputs_num);
179 } /* sn_network_t *get_next */
181 static void random_walk (sn_network_t *n)
183 uint64_t iteration_counter = 0;
187 sn_network_t *next = get_next (n);
192 fprintf (stderr, "get_next() failed.\n");
196 rating = rate_network (next);
197 if (rating < best_rating)
199 printf ("New best rating (%i) after %"PRIu64" iterations.\n",
200 rating, iteration_counter);
202 best_rating = rating;
203 sn_network_destroy (best_solution);
204 best_solution = sn_network_clone (next);
207 sn_network_destroy (n);
211 if ((max_iterations > 0) && (iteration_counter >= max_iterations))
213 } /* while (do_loop) */
215 sn_network_destroy (n);
217 printf ("Exiting after %"PRIu64" iterations.\n", iteration_counter);
218 } /* void random_walk */
220 int main (int argc, char **argv)
222 sn_network_t *start_network;
224 struct sigaction sigint_action;
225 struct sigaction sigterm_action;
227 read_options (argc, argv);
228 if (initial_input_file == NULL)
229 exit_usage (argv[0], EXIT_FAILURE);
231 memset (&sigint_action, '\0', sizeof (sigint_action));
232 sigint_action.sa_handler = sigint_handler;
233 sigaction (SIGINT, &sigint_action, NULL);
235 memset (&sigterm_action, '\0', sizeof (sigterm_action));
236 sigterm_action.sa_handler = sigint_handler;
237 sigaction (SIGTERM, &sigterm_action, NULL);
239 start_network = sn_network_read_file (initial_input_file);
240 if (start_network == NULL)
242 printf ("start_network == NULL\n");
246 inputs_num = SN_NETWORK_INPUT_NUM(start_network);
248 printf ("Current configuration:\n"
249 " Initial network: %s\n"
250 " Number of inputs: %3i\n"
251 "=======================\n",
252 initial_input_file, inputs_num);
254 random_walk (start_network);
255 start_network = NULL;
257 if (best_solution != NULL)
259 if (best_output_file != NULL)
260 sn_network_write_file (best_solution, best_output_file);
262 printf ("=== Best solution (rating: %i) ===\n", best_rating);
263 sn_network_normalize (best_solution);
264 sn_network_show (best_solution);
265 sn_network_destroy (best_solution);
272 /* vim: set shiftwidth=2 softtabstop=2 : */