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 +1,103 @@
+/* -*- mode: C++ -*-  */
+/*
+   igraph library.
+   Copyright (C) 2011-2012  Gabor Csardi <csardi.gabor@gmail.com>
+   334 Harvard st, Cambridge MA, 02139 USA
+
+   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, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301 USA
+
+*/
+
+#include <igraph.h>
+#include <stdio.h>
+
+#include "test_utilities.h"
+
+int main(void) {
+    igraph_t graph;
+    igraph_t full, tree;
+    igraph_hrg_t hrg;
+    igraph_t dendrogram;
+    igraph_vector_t prob;
+
+    igraph_rng_seed(igraph_rng_default(), 42);
+
+    igraph_full(&full, 10, IGRAPH_UNDIRECTED, IGRAPH_NO_LOOPS);
+    igraph_kary_tree(&tree, 15, /*children=*/ 2, /*type=*/ IGRAPH_TREE_UNDIRECTED);
+    igraph_disjoint_union(&graph, &full, &tree);
+    igraph_add_edge(&graph, 0, 10);
+
+    igraph_destroy(&full);
+    igraph_destroy(&tree);
+
+    // Fit
+    igraph_hrg_init(&hrg, igraph_vcount(&graph));
+    igraph_hrg_fit(&graph, &hrg, /*start=*/ false, /*steps=*/ 0);
+
+    // Create a graph from it
+    igraph_vector_init(&prob, 0);
+    igraph_from_hrg_dendrogram(&dendrogram, &hrg, &prob);
+
+    // Print the tree, with labels
+    igraph_vector_int_t neis;
+    igraph_vector_int_init(&neis, 0);
+    for (igraph_int_t i=0; i < igraph_vcount(&graph)-1; i++) {
+        printf("Vertex # %2" IGRAPH_PRId ", ", (i+igraph_vcount(&graph)));
+        igraph_neighbors(
+            &dendrogram, &neis, i+igraph_vcount(&graph), IGRAPH_OUT,
+            IGRAPH_LOOPS_ONCE, IGRAPH_MULTIPLE
+        );
+        printf("left: # %2" IGRAPH_PRId ", right: # %2" IGRAPH_PRId ", ", VECTOR(neis)[0], VECTOR(neis)[1]);
+        printf("prob: %6.2g\n", VECTOR(prob)[i+igraph_vcount(&graph)]);
+    }
+    igraph_vector_int_destroy(&neis);
+
+    igraph_vector_destroy(&prob);
+    igraph_destroy(&dendrogram);
+    igraph_hrg_destroy(&hrg);
+    igraph_destroy(&graph);
+
+    // test small graph, omit probabilities
+    igraph_small(&graph, 3, IGRAPH_UNDIRECTED,
+                 0,1,
+                 -1);
+
+    igraph_hrg_init(&hrg, igraph_vcount(&graph));
+    igraph_hrg_fit(&graph, &hrg, /*start=*/ false, /*steps=*/ 0);
+    igraph_from_hrg_dendrogram(&dendrogram, &hrg, NULL);
+    igraph_destroy(&dendrogram);
+    igraph_hrg_destroy(&hrg);
+
+    // test with a specific number of steps
+    igraph_hrg_init(&hrg, igraph_vcount(&graph));
+    igraph_hrg_fit(&graph, &hrg, /*start=*/ false, /*steps=*/ 10);
+    igraph_from_hrg_dendrogram(&dendrogram, &hrg, NULL);
+    igraph_destroy(&dendrogram);
+    igraph_hrg_destroy(&hrg);
+
+    igraph_destroy(&graph);
+
+    // graph must have at least 3 vertices at the moment
+    igraph_full(&graph, 2, IGRAPH_UNDIRECTED, IGRAPH_NO_LOOPS);
+    igraph_hrg_init(&hrg, igraph_vcount(&graph));
+    CHECK_ERROR(igraph_hrg_fit(&graph, &hrg, /*start=*/ false, /*steps=*/ 0), IGRAPH_EINVAL);
+    igraph_hrg_destroy(&hrg);
+    igraph_destroy(&graph);
+
+    VERIFY_FINALLY_STACK();
+
+    return 0;
+}