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 +1,96 @@
+/*
+   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"
+
+int main(void) {
+    igraph_t graph;
+    igraph_vector_int_t edge_walk, vertex_walk;
+
+    igraph_vector_int_init(&vertex_walk, 0);
+    igraph_vector_int_init(&edge_walk, 0);
+
+    igraph_ring(&graph, 4, IGRAPH_DIRECTED, false, true);
+    igraph_vector_int_range(&edge_walk, 0, igraph_ecount(&graph));
+
+    printf("Cycle, detect start:\n");
+    igraph_vertex_path_from_edge_path(&graph, -1, &edge_walk, &vertex_walk, IGRAPH_ALL);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    printf("\nCycle plus one vertex, start given:\n");
+    igraph_vector_int_push_back(&edge_walk, 0);
+    igraph_vertex_path_from_edge_path(&graph, 0, &edge_walk, &vertex_walk, IGRAPH_ALL);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    /* Inconsistent start vertex */
+    CHECK_ERROR(
+        igraph_vertex_path_from_edge_path(&graph, 1, &edge_walk, &vertex_walk, IGRAPH_ALL),
+        IGRAPH_EINVAL
+    );
+
+    /* Invalid start vertex */
+    CHECK_ERROR(
+        igraph_vertex_path_from_edge_path(&graph, 10, &edge_walk, &vertex_walk, IGRAPH_ALL),
+        IGRAPH_EINVVID
+    );
+
+    printf("\nSingle edge, detect start:\n");
+    igraph_vector_int_clear(&edge_walk);
+    igraph_vector_int_push_back(&edge_walk, 2);
+    igraph_vertex_path_from_edge_path(&graph, -1, &edge_walk, &vertex_walk, IGRAPH_ALL);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    printf("\nSingle edge, directed OUT, detect start:\n");
+    igraph_vector_int_clear(&edge_walk);
+    igraph_vector_int_push_back(&edge_walk, 2);
+    igraph_vertex_path_from_edge_path(&graph, -1, &edge_walk, &vertex_walk, IGRAPH_OUT);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    printf("\nSingle edge, directed IN, detect start:\n");
+    igraph_vector_int_clear(&edge_walk);
+    igraph_vector_int_push_back(&edge_walk, 2);
+    igraph_vertex_path_from_edge_path(&graph, -1, &edge_walk, &vertex_walk, IGRAPH_IN);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    printf("\nZero edges, start given:\n");
+    igraph_vector_int_clear(&edge_walk);
+    igraph_vertex_path_from_edge_path(&graph, 2, &edge_walk, &vertex_walk, IGRAPH_ALL);
+    print_vector_int(&edge_walk);
+    print_vector_int(&vertex_walk);
+
+    /* Zero edges, start not given: */
+    CHECK_ERROR(
+        igraph_vertex_path_from_edge_path(&graph, -1, &edge_walk, &vertex_walk, IGRAPH_ALL),
+        IGRAPH_EINVAL
+    );
+
+    igraph_destroy(&graph);
+    igraph_vector_int_destroy(&edge_walk);
+    igraph_vector_int_destroy(&vertex_walk);
+
+    VERIFY_FINALLY_STACK();
+
+    return 0;
+}