int main() {
igraph_t g;
igraph_vector_ptr_t vecs;
long int i;
igraph_vs_t vs;
igraph_ring(&g, 10, IGRAPH_DIRECTED, 0, 1);
igraph_vector_ptr_init(&vecs, 5);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
VECTOR(vecs)[i] = calloc(1, sizeof(igraph_vector_t));
igraph_vector_init(VECTOR(vecs)[i], 0);
}
igraph_vs_vector_small(&vs, 1, 3, 5, 2, 1, -1);
igraph_get_shortest_paths(&g, &vecs, 0, vs, IGRAPH_OUT);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
print_vector(VECTOR(vecs)[i]);
igraph_vector_destroy(VECTOR(vecs)[i]);
free(VECTOR(vecs)[i]);
}
igraph_vector_ptr_destroy(&vecs);
igraph_vs_destroy(&vs);
igraph_destroy(&g);
return 0;
}
int main(int argc, char*argv[]) {
// the graph is just a list og from to identifier pairs, one per line
if (argc != 4) {
fprintf (stderr, "Usage: %s <path to graph> <from id> <to id>\n", argv[0]);
exit(1);
}
// 57572 DOCK6
// 7049 TGFBR3
// 2263 FGFBP3
igraph_vs_t vertex_to;
igraph_integer_t vertex_from;
vertex_from = atol(argv[2]);
// in principle, unumber of "to" vertices is arbitrary,
// but that is a piece of code I will write some other time
//igraph_vs_vector_small(&vertex_to, 2263, 7049, -1);
igraph_vs_vector_small(&vertex_to, atol(argv[3]), -1);
igraph_t graph;
/*The number of vertices in the graph. If smaller than the largest integer in
the file it will be ignored. It is thus safe to supply zero here. */
igraph_integer_t zero = 0;
FILE * infile = efopen(argv[1], "r") ;
igraph_bool_t directed = IGRAPH_UNDIRECTED;
igraph_read_graph_edgelist (&graph, infile, zero, directed);
/* shortest path calculation: */
/* http://igraph.org/c/doc/igraph-Structural.html#igraph_get_all_shortest_paths
int igraph_get_all_shortest_paths(const igraph_t *graph,
igraph_vector_ptr_t *res,
igraph_vector_t *nrgeo,
igraph_integer_t from, const igraph_vs_t to,
igraph_neimode_t mode);
*/
igraph_vector_ptr_t result;
igraph_vector_t nrgeo;
igraph_integer_t i;
// the second argument here is the number of "to" vertices
igraph_vector_ptr_init (&result, 1);
igraph_vector_init(&nrgeo, 0);
igraph_get_all_shortest_paths (&graph, &result, &nrgeo,
vertex_from, vertex_to,
IGRAPH_ALL);
for (i=0; i<igraph_vector_ptr_size(&result); i++) {
print_vector(VECTOR(result)[i]);
}
igraph_vector_ptr_destroy(&result);
igraph_vs_destroy(&vertex_to);
igraph_destroy(&graph);
if (!IGRAPH_FINALLY_STACK_EMPTY) return 1;
return 0;
}
int main() {
igraph_t g;
igraph_vector_t v=IGRAPH_VECTOR_NULL;
igraph_real_t edges[] = { 0,1, 1,2, 2,2, 2,3, 2,4, 3,4 };
igraph_vector_t v2;
long int i;
igraph_vit_t vit;
igraph_vs_t vs;
igraph_integer_t size;
igraph_vector_view(&v, edges, sizeof(edges)/sizeof(igraph_real_t));
igraph_create(&g, &v, 0, IGRAPH_DIRECTED);
/* Create iterator based on a vector (view) */
igraph_vector_init(&v2, 6);
VECTOR(v2)[0]=0; VECTOR(v2)[1]=2;
VECTOR(v2)[2]=4; VECTOR(v2)[3]=0;
VECTOR(v2)[4]=2; VECTOR(v2)[5]=4;
igraph_vit_create(&g, igraph_vss_vector(&v2), &vit);
i=0;
while (!IGRAPH_VIT_END(vit)) {
if (IGRAPH_VIT_GET(vit) != VECTOR(v2)[i]) {
return 1;
}
IGRAPH_VIT_NEXT(vit);
i++;
}
if (i != igraph_vector_size(&v2)) {
return 2;
}
igraph_vit_destroy(&vit);
igraph_vector_destroy(&v2);
/* Create small vector iterator */
igraph_vs_vector_small(&vs, 0, 2, 4, 0, 2, 4, 2, -1);
igraph_vit_create(&g, vs, &vit);
igraph_vs_size(&g, &vs, &size);
printf("%li ", (long int) size);
for (; !IGRAPH_VIT_END(vit); IGRAPH_VIT_NEXT(vit)) {
printf("%li ", (long int) IGRAPH_VIT_GET(vit));
}
printf("\n");
igraph_vit_destroy(&vit);
igraph_vs_destroy(&vs);
/* Clean up */
igraph_destroy(&g);
return 0;
}
int main() {
igraph_t g;
igraph_vector_ptr_t vecs;
long int i;
igraph_real_t weights[] = { 1, 2, 3, 4, 5, 1, 1, 1, 1, 1 };
igraph_real_t weights2[] = { 0,2,1, 0,5,2, 1,1,0, 2,2,8, 1,1,3, 1,1,4, 2,1 };
igraph_vector_t weights_vec;
igraph_vs_t vs;
/* Simple ring graph without weights */
igraph_ring(&g, 10, IGRAPH_UNDIRECTED, 0, 1);
igraph_vector_ptr_init(&vecs, 5);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
VECTOR(vecs)[i] = calloc(1, sizeof(igraph_vector_t));
igraph_vector_init(VECTOR(vecs)[i], 0);
}
igraph_vs_vector_small(&vs, 1, 3, 5, 2, 1, -1);
igraph_get_shortest_paths_dijkstra(&g, &vecs, 0, vs, 0, IGRAPH_OUT);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++)
print_vector(VECTOR(vecs)[i]);
/* Same ring, but with weights */
igraph_vector_view(&weights_vec, weights, sizeof(weights)/sizeof(igraph_real_t));
igraph_get_shortest_paths_dijkstra(&g, &vecs, 0, vs, &weights_vec, IGRAPH_OUT);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++)
print_vector(VECTOR(vecs)[i]);
igraph_destroy(&g);
/* More complicated example */
igraph_small(&g, 10, IGRAPH_DIRECTED,
0,1, 0,2, 0,3, 1,2, 1,4, 1,5,
2,3, 2,6, 3,2, 3,6,
4,5, 4,7, 5,6, 5,8, 5,9,
7,5, 7,8, 8,9,
5,2,
2,1,
-1);
igraph_vector_view(&weights_vec, weights2, sizeof(weights2)/sizeof(igraph_real_t));
igraph_get_shortest_paths_dijkstra(&g, &vecs, 0, vs, &weights_vec, IGRAPH_OUT);
for (i=0; i<igraph_vector_ptr_size(&vecs); i++) {
print_vector(VECTOR(vecs)[i]);
igraph_vector_destroy(VECTOR(vecs)[i]);
free(VECTOR(vecs)[i]);
}
igraph_vector_ptr_destroy(&vecs);
igraph_vs_destroy(&vs);
igraph_destroy(&g);
if (!IGRAPH_FINALLY_STACK_EMPTY) return 1;
return 0;
}
int main() {
igraph_t g, g2;
igraph_vector_ptr_t sep;
igraph_vs_t vs;
igraph_small(&g, 7, IGRAPH_UNDIRECTED,
1,0, 2,0, 3,0, 4,0, 5,0, 6,0,
-1);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
print_and_destroy(&sep);
igraph_destroy(&g);
/* ----------------------------------------------------------- */
igraph_small(&g, 5, IGRAPH_UNDIRECTED,
0,3, 1,3, 2,3,
0,4, 1,4, 2,4,
-1);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
print_and_destroy(&sep);
igraph_destroy(&g);
/* ----------------------------------------------------------- */
igraph_small(&g, 5, IGRAPH_UNDIRECTED,
2,0, 3,0, 4,0,
2,1, 3,1, 4,1,
-1);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
print_and_destroy(&sep);
igraph_destroy(&g);
/* ----------------------------------------------------------- */
igraph_small(&g, 10, IGRAPH_UNDIRECTED,
0,2, 0,3, 1,2, 1,3, 5,2, 5,3, 6,2, 6,3,
7,2, 7,3, 8,2, 8,3, 9,2, 9,3,
2,4, 4,3,
-1);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
print_and_destroy(&sep);
igraph_destroy(&g);
/* ----------------------------------------------------------- */
igraph_full(&g, 4, IGRAPH_UNDIRECTED, /*loops=*/ 0);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
print_and_destroy(&sep);
igraph_destroy(&g);
/* ----------------------------------------------------------- */
igraph_small(&g, 23, IGRAPH_UNDIRECTED,
0,1, 0,2, 0,3, 0,4, 0,5,
1,2, 1,3, 1,4, 1,6,
2,3, 2,5, 2,6,
3,4, 3,5, 3,6,
4,5, 4,6, 4,20,
5,6,
6,7, 6,10, 6,13, 6,18,
7,8, 7,10, 7,13,
8,9,
9,11, 9,12,
10,11, 10,13,
11,15,
12,15,
13,14,
14,15,
16,17, 16,18, 16,19,
17,19, 17,20,
18,19, 18,21, 18,22,
19,20,
20,21, 20,22,
21,22,
-1);
igraph_vector_ptr_init(&sep, 0);
igraph_minimum_size_separators(&g, &sep);
printf("Orig:\n"); print_and_destroy(&sep);
igraph_vector_ptr_init(&sep, 0);
igraph_vs_vector_small(&vs, 0,1,2,3,4,5,6, 16,17,18,19,20,21,22, -1);
igraph_induced_subgraph(&g, &g2, vs, IGRAPH_SUBGRAPH_AUTO);
igraph_minimum_size_separators(&g2, &sep);
printf("1-7,17-23:\n"); print_and_destroy(&sep);
igraph_vs_destroy(&vs);
igraph_destroy(&g2);
igraph_vector_ptr_init(&sep, 0);
igraph_vs_vector_small(&vs, 6,7,8,9,10,11,12,13,14,15, -1);
igraph_induced_subgraph(&g, &g2, vs, IGRAPH_SUBGRAPH_AUTO);
igraph_minimum_size_separators(&g2, &sep);
printf("7-16:\n"); print_and_destroy(&sep);
igraph_vs_destroy(&vs);
igraph_destroy(&g2);
igraph_vector_ptr_init(&sep, 0);
igraph_vs_vector_small(&vs, 16,17,18,19,20,21,22, -1);
igraph_induced_subgraph(&g, &g2, vs, IGRAPH_SUBGRAPH_AUTO);
igraph_minimum_size_separators(&g2, &sep);
printf("17-23:\n"); print_and_destroy(&sep);
igraph_vs_destroy(&vs);
igraph_destroy(&g2);
igraph_vector_ptr_init(&sep, 0);
igraph_vs_vector_small(&vs, 6,7,10,13, -1);
igraph_induced_subgraph(&g, &g2, vs, IGRAPH_SUBGRAPH_AUTO);
igraph_minimum_size_separators(&g2, &sep);
printf("7,8,11,14:\n"); print_and_destroy(&sep);
igraph_vs_destroy(&vs);
igraph_destroy(&g2);
igraph_vector_ptr_init(&sep, 0);
igraph_vs_vector_small(&vs, 0,1,2,3,4,5,6, -1);
igraph_induced_subgraph(&g, &g2, vs, IGRAPH_SUBGRAPH_AUTO);
igraph_minimum_size_separators(&g2, &sep);
printf("1-7:\n"); print_and_destroy(&sep);
igraph_vs_destroy(&vs);
igraph_destroy(&g2);
igraph_destroy(&g);
return 0;
}
