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/* -*- mode: C -*- */
/*
IGraph R library.
Copyright (C) 2011-2012 Gabor Csardi <csardi.gabor@gmail.com>
334 Harvard street, Cambridge MA, 02139 USA
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include <igraph.h>
#include <stdio.h>
#define N 1000
igraph_bool_t has_loops(const igraph_t *graph) {
int i, n=igraph_ecount(graph);
for (i=0; i<n; i++) {
if (IGRAPH_FROM(graph, i) == IGRAPH_TO(graph, i)) { return 1; }
}
return 0;
}
igraph_bool_t has_multiple(const igraph_t *graph) {
igraph_bool_t res;
igraph_has_multiple(graph, &res);
return res;
}
#define ERR() do { \
printf("Seed: %d\n", seed); \
igraph_write_graph_edgelist(&ws, stdout); \
} while (0)
#define SEED() do { \
seed=igraph_rng_get_integer(igraph_rng_default(), 1, 10000); \
igraph_rng_seed(igraph_rng_default(), seed); \
} while (0)
int main() {
igraph_t ws;
igraph_bool_t sim, seen_loops, seen_multiple;
int i, seed=1305473657;
igraph_rng_seed(igraph_rng_default(), seed);
/* No loops, no multiple edges */
for (i=0; i<N; i++) {
SEED();
igraph_watts_strogatz_game(&ws, /*dim=*/ 1, /*size=*/ 5, /*nei=*/ 1,
/*p=*/ 0.5, /*loops=*/ 0, /*multiple=*/ 0);
igraph_is_simple(&ws, &sim); if (!sim) { ERR(); return 1; }
if (has_loops(&ws)) { ERR(); return 1; }
if (has_multiple(&ws)) { ERR(); return 2; }
igraph_destroy(&ws);
}
/* No loops, multiple edges possible */
seen_multiple=0;
for (i=0; i<N; i++) {
SEED();
igraph_watts_strogatz_game(&ws, /*dim=*/ 1, /*size=*/ 5, /*nei=*/ 1,
/*p=*/ 0.5, /*loops=*/ 0, /*multiple=*/ 1);
if (has_loops(&ws)) { ERR(); return 3; }
seen_multiple = seen_multiple || has_multiple(&ws);
igraph_destroy(&ws);
}
/* This might actually happen */
/* if (!seen_multiple) { return 4; } */
/* Loops possible, no multiple edges */
seen_loops=0;
for (i=0; i<N; i++) {
SEED();
igraph_watts_strogatz_game(&ws, /*dim=*/ 1, /*size=*/ 5, /*nei=*/ 1,
/*p=*/ 0.5, /*loops=*/ 1, /*multiple=*/ 0);
if (has_multiple(&ws)) { return 5; }
seen_loops = seen_loops || has_loops(&ws);
igraph_destroy(&ws);
}
/* This might actually happen */
/* if (!seen_loops) { return 6; } */
/* Both loops and multiple edges are possible */
for (i=0; i<N; i++) {
SEED();
igraph_watts_strogatz_game(&ws, /*dim=*/ 1, /*size=*/ 5, /*nei=*/ 1,
/*p=*/ 0.5, /*loops=*/ 1, /*multiple=*/ 1);
seen_loops = seen_loops || has_loops(&ws);
seen_multiple = seen_multiple || has_multiple(&ws);
igraph_destroy(&ws);
}
/* This might actually happen */
/* if (!seen_loops) { return 7; } */
/* if (!seen_multiple) { return 8; } */
return 0;
}
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