/* -*- mode: C -*- */ /* IGraph library. Copyright (C) 2006-2012 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> void show_results(igraph_t *g, igraph_vector_t *mod, igraph_matrix_t *merges, FILE* f) { long int i; igraph_vector_t membership; igraph_vector_init(&membership, 0); i=igraph_vector_which_max(mod); fprintf(f, "Modularity: %f\n", VECTOR(*mod)[i]); igraph_community_to_membership(merges, igraph_vcount(g), i, &membership, 0); printf("Membership: "); for (i=0; i<igraph_vector_size(&membership); i++) { printf("%li ", (long int)VECTOR(membership)[i]); } printf("\n"); igraph_vector_destroy(&membership); } int main() { igraph_t g; igraph_vector_t modularity, weights; igraph_matrix_t merges; igraph_vector_init(&modularity,0); igraph_matrix_init(&merges,0,0); igraph_vector_init(&weights,0); /* Simple unweighted graph */ igraph_small(&g, 10, IGRAPH_UNDIRECTED, 0,1,0,2,0,3,0,4, 1,2,1,3,1,4, 2,3,2,4, 3,4, 5,6,5,7,5,8,5,9, 6,7,6,8,6,9, 7,8,7,9, 8,9, 0,5, -1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); /* Same simple graph, with uniform edge weights */ igraph_vector_resize(&weights, igraph_ecount(&g)); igraph_vector_fill(&weights, 2); igraph_community_fastgreedy(&g, &weights, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Simple nonuniform weighted graph, with and without weights */ igraph_small(&g, 6, IGRAPH_UNDIRECTED, 0,1,1,2,2,3,2,4,2,5,3,4,3,5,4,5, -1); igraph_vector_resize(&weights, 8); igraph_vector_fill(&weights, 1); VECTOR(weights)[0] = 10; VECTOR(weights)[1] = 10; igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_community_fastgreedy(&g, &weights, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Zachary Karate club */ igraph_small(&g, 0, IGRAPH_UNDIRECTED, 0, 1, 0, 2, 0, 3, 0, 4, 0, 5, 0, 6, 0, 7, 0, 8, 0, 10, 0, 11, 0, 12, 0, 13, 0, 17, 0, 19, 0, 21, 0, 31, 1, 2, 1, 3, 1, 7, 1, 13, 1, 17, 1, 19, 1, 21, 1, 30, 2, 3, 2, 7, 2, 8, 2, 9, 2, 13, 2, 27, 2, 28, 2, 32, 3, 7, 3, 12, 3, 13, 4, 6, 4, 10, 5, 6, 5, 10, 5, 16, 6, 16, 8, 30, 8, 32, 8, 33, 9, 33, 13, 33, 14, 32, 14, 33, 15, 32, 15, 33, 18, 32, 18, 33, 19, 33, 20, 32, 20, 33, 22, 32, 22, 33, 23, 25, 23, 27, 23, 29, 23, 32, 23, 33, 24, 25, 24, 27, 24, 31, 25, 31, 26, 29, 26, 33, 27, 33, 28, 31, 28, 33, 29, 32, 29, 33, 30, 32, 30, 33, 31, 32, 31, 33, 32, 33, -1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Simple disconnected graph with isolates */ igraph_small(&g, 9, IGRAPH_UNDIRECTED, 0, 1, 0, 2, 0, 3, 1, 2, 1, 3, 2, 3, 4, 5, 4, 6, 4, 7, 5, 6, 5, 7, 6, 7, -1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Disjoint union of two rings */ igraph_small(&g, 20, IGRAPH_UNDIRECTED, 0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,0,9, 10,11,11,12,12,13,13,14,14,15,15,16,16,17,17,18,18,19,10,19,-1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Completely empty graph */ igraph_small(&g, 10, IGRAPH_UNDIRECTED, -1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Ring graph with loop edges */ igraph_small(&g, 6, IGRAPH_UNDIRECTED, 0,1,1,2,2,3,3,4,4,5,5,0,0,0,2,2,-1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); /* Regression test -- graph with two vertices and two edges */ igraph_small(&g, 2, IGRAPH_UNDIRECTED, 0,0,1,1,-1); igraph_community_fastgreedy(&g, 0, &merges, &modularity, /*membership=*/ 0); show_results(&g, &modularity, &merges, stdout); igraph_destroy(&g); igraph_vector_destroy(&modularity); igraph_vector_destroy(&weights); igraph_matrix_destroy(&merges); return 0; }