int main(void) {
igraph_real_t avg_path;
igraph_t graph;
igraph_vector_t dimvector;
igraph_vector_t edges;
int i;
igraph_vector_init(&dimvector, 2);
VECTOR(dimvector)[0]=30;
VECTOR(dimvector)[1]=30;
igraph_lattice(&graph, &dimvector, 0, IGRAPH_UNDIRECTED, 0, 1);
igraph_rng_seed(igraph_rng_default(), 42);
igraph_vector_init(&edges, 20);
for (i=0; i<igraph_vector_size(&edges); i++) {
VECTOR(edges)[i] = rand() % (int)igraph_vcount(&graph);
}
igraph_average_path_length(&graph, &avg_path, IGRAPH_UNDIRECTED, 1);
printf("Average path length (lattice): %f\n", (double) avg_path);
igraph_add_edges(&graph, &edges, 0);
igraph_average_path_length(&graph, &avg_path, IGRAPH_UNDIRECTED, 1);
printf("Average path length (randomized lattice): %f\n", (double) avg_path);
igraph_vector_destroy(&dimvector);
igraph_vector_destroy(&edges);
igraph_destroy(&graph);
return 0;
}
int main() {
igraph_t g;
igraph_real_t result;
igraph_rng_t rng;
igraph_rng_init(&rng, &igraph_rngtype_mt19937);
igraph_barabasi_game(&g, 30, /*power=*/ 1, 30, 0, 0, /*A=*/ 1,
IGRAPH_DIRECTED, IGRAPH_BARABASI_BAG,
/*start_from=*/ 0, &rng);
igraph_average_path_length(&g, &result, IGRAPH_UNDIRECTED, 1);
/* printf("Length of the average shortest paths: %f\n", (float) result); */
igraph_destroy(&g);
igraph_rng_destroy(&rng);
return 0;
}
double Graph::avgPathLength() {
igraph_real_t res;
igraph_average_path_length(graph, &res, 0, 0);
return double(res);
}
double Graph::avgPathLength() const {
igraph_real_t res;
igraph_average_path_length(graph, &res, 0, 0);
return ((double) res);
}
