Add graph references

2026-06-28 13:49:01 +01:00
parent 0a9807e448
commit a11edf0c53
2578 changed files with 868045 additions and 0 deletions
@@ -0,0 +1,129 @@
+/*
+   igraph library.
+   Copyright (C) 2024  The igraph development team <igraph@igraph.org>
+
+   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, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <igraph.h>
+
+#include "test_utilities.h"
+
+void compute_and_print(const igraph_t *g, igraph_neimode_t mode) {
+    igraph_vector_int_t membership, csize, reach_counts;
+    igraph_bitset_list_t reach;
+    igraph_int_t no_of_nodes, no_of_components;
+
+    no_of_nodes = igraph_vcount(g);
+
+    igraph_vector_int_init(&membership, 0);
+    igraph_vector_int_init(&csize, 0);
+    igraph_bitset_list_init(&reach, 0);
+
+    igraph_reachability(g, &membership, &csize, &no_of_components, &reach, mode);
+
+    igraph_vector_int_init(&reach_counts, no_of_nodes);
+
+    igraph_count_reachable(g, &reach_counts, mode);
+
+    printf("Mode: ");
+    switch (mode) {
+    case IGRAPH_OUT:
+        printf("OUT\n"); break;
+    case IGRAPH_IN:
+        printf("IN\n"); break;
+    case IGRAPH_ALL:
+        printf("ALL\n"); break;
+    }
+    print_vector_int(&membership);
+    print_vector_int(&csize);
+    printf("No. of components: %" IGRAPH_PRId "\n", no_of_components);
+    print_bitset_list(&reach);
+    print_vector_int(&reach_counts);
+
+    igraph_bitset_list_destroy(&reach);
+    igraph_vector_int_destroy(&csize);
+    igraph_vector_int_destroy(&membership);
+    igraph_vector_int_destroy(&reach_counts);
+}
+
+int main(void) {
+    igraph_t g;
+
+    /* Component calculations are run twice to exercise the cache */
+
+    printf("\nNull graph (not connected)\n");
+    igraph_empty(&g, 0, IGRAPH_DIRECTED);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nSingleton graph (connected)\n");
+    igraph_empty(&g, 1, IGRAPH_DIRECTED);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nKautz graph (connected)\n");
+    igraph_kautz(&g, 2, 2);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nDirected 2-path\n");
+    igraph_small(&g, 2, IGRAPH_DIRECTED, 0, 1, -1);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nTwo disjoint 3-cycles\n");
+    igraph_small(&g, 6, IGRAPH_DIRECTED, 0, 1, 1, 2, 2, 0, 3, 4, 4, 5, 5, 3, -1);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_IN);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nPath graph with 6 vertices ascending\n");
+    igraph_small(&g, 6, IGRAPH_DIRECTED, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, -1);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_IN);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nPath graph with 6 vertices descending\n");
+    igraph_small(&g, 6, IGRAPH_DIRECTED, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, -1);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_IN);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nSmall directed graph\n");
+    igraph_small(&g, 13, IGRAPH_DIRECTED, 0, 1, 1, 2, 2, 0, 1, 3, 3, 4, 4, 5, 5, 4, 7, 4, 7, 8, 9, 8, 10, 9, 8, 10, 11, 6, 12, 6, -1);
+    compute_and_print(&g, IGRAPH_OUT);
+    compute_and_print(&g, IGRAPH_IN);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    printf("\nSmall undirected graph\n");
+    igraph_small(&g, 6, IGRAPH_UNDIRECTED,
+                 0,1, 1,2, 0,2,
+                 3,4,
+                 -1);
+    compute_and_print(&g, IGRAPH_ALL);
+    igraph_destroy(&g);
+
+    VERIFY_FINALLY_STACK();
+
+    return 0;
+}