Ejemplos de igraph_vector_which_max en C++ (Cpp)

Ejemplo n.º 1

Archivo: bgldet.c Proyecto: drishti95/Randomisation

void show_results(igraph_t *g, igraph_vector_t *membership, igraph_matrix_t *memberships, igraph_vector_t *modularity, FILE* f) {
  long int i, j, no_of_nodes = igraph_vcount(g);

  j=igraph_vector_which_max(modularity);
  for (i=0; i<igraph_vector_size(membership); i++) {
    if (VECTOR(*membership)[i] != MATRIX(*memberships, j, i)) {
      fprintf(f, "WARNING: best membership vector element %li does not match the best one in the membership matrix\n", i);
    }
  }

  fprintf(f, "Modularities:\n");
  igraph_vector_print(modularity);

  for (i=0; i < igraph_matrix_nrow(memberships); i++) {
    for (j=0; j < no_of_nodes; j++) {
      fprintf(f, "%ld ", (long int)MATRIX(*memberships, i, j));
    }
    fprintf(f, "\n");
  }

  fprintf(f, "\n");
}

Ejemplo n.º 2

Archivo: coloring.c Proyecto: cran/igraph

int igraph_i_vertex_coloring_greedy_cn(const igraph_t *graph, igraph_vector_int_t *colors) {
    long i, vertex, maxdeg;
    long vc = igraph_vcount(graph);
    igraph_2wheap_t cn; /* indexed heap storing number of already coloured neighbours */
    igraph_vector_int_t neigh_colors;
    igraph_adjlist_t adjlist;

    IGRAPH_CHECK(igraph_vector_int_resize(colors, vc));
    igraph_vector_int_fill(colors, 0);

    /* Nothing to do for 0 or 1 vertices.
     * Remember that colours are integers starting from 0,
     * and the 'colors' vector is already 0-initialized above.
     */
    if (vc <= 1)
        return IGRAPH_SUCCESS;

    IGRAPH_CHECK(igraph_adjlist_init(graph, &adjlist, IGRAPH_ALL));
    IGRAPH_FINALLY(igraph_adjlist_destroy, &adjlist);

    /* find maximum degree and a corresponding vertex */
    {
        igraph_vector_t degree;

        IGRAPH_CHECK(igraph_vector_init(&degree, 0));
        IGRAPH_FINALLY(igraph_vector_destroy, &degree);
        IGRAPH_CHECK(igraph_degree(graph, &degree, igraph_vss_all(), IGRAPH_ALL, 0));

        vertex = igraph_vector_which_max(&degree);
        maxdeg = VECTOR(degree)[vertex];

        igraph_vector_destroy(&degree);
        IGRAPH_FINALLY_CLEAN(1);
    }

    IGRAPH_CHECK(igraph_vector_int_init(&neigh_colors, 0));
    IGRAPH_CHECK(igraph_vector_int_reserve(&neigh_colors, maxdeg));
    IGRAPH_FINALLY(igraph_vector_int_destroy, &neigh_colors);

    IGRAPH_CHECK(igraph_2wheap_init(&cn, vc));
    IGRAPH_FINALLY(igraph_2wheap_destroy, &cn);
    for (i=0; i < vc; ++i)
        if (i != vertex)
            igraph_2wheap_push_with_index(&cn, i, 0); /* should not fail since memory was already reserved */

    while (1) {
        igraph_vector_int_t *neighbors = igraph_adjlist_get(&adjlist, vertex);
        long neigh_count = igraph_vector_int_size(neighbors);

        /* colour current vertex */
        {
            igraph_integer_t col;

            IGRAPH_CHECK(igraph_vector_int_resize(&neigh_colors, neigh_count));
            for (i=0; i < neigh_count; ++i)
                VECTOR(neigh_colors)[i] = VECTOR(*colors)[ VECTOR(*neighbors)[i] ];
            igraph_vector_int_sort(&neigh_colors);

            i=0;
            col = 0;
            do {
                while (i < neigh_count && VECTOR(neigh_colors)[i] == col)
                    i++;
                col++;
            } while (i < neigh_count && VECTOR(neigh_colors)[i] == col);

            VECTOR(*colors)[vertex] = col;
        }

        /* increment number of coloured neighbours for each neighbour of vertex */
        for (i=0; i < neigh_count; ++i) {
            long idx = VECTOR(*neighbors)[i];
            if (igraph_2wheap_has_elem(&cn, idx))
                igraph_2wheap_modify(&cn, idx, igraph_2wheap_get(&cn, idx) + 1);
        }

        /* stop if no more vertices left to colour */
        if (igraph_2wheap_empty(&cn))
            break;

        igraph_2wheap_delete_max_index(&cn, &vertex);

        IGRAPH_ALLOW_INTERRUPTION();
    }

    /* subtract 1 from each colour value, so that colours start at 0 */
    igraph_vector_int_add_constant(colors, -1);

    /* free data structures */
    igraph_vector_int_destroy(&neigh_colors);
    igraph_adjlist_destroy(&adjlist);
    igraph_2wheap_destroy(&cn);
    IGRAPH_FINALLY_CLEAN(3);

    return IGRAPH_SUCCESS;
}