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 +1,70 @@
+/* igraph library.
+   Copyright (C) 2007-2022  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>
+
+int main(void) {
+
+    igraph_t g;
+    igraph_vector_t y;
+    igraph_warning_handler_t* oldwarnhandler;
+
+    /* Initialize the library. */
+    igraph_setup();
+
+    /* Turn on attribute handling. */
+    igraph_set_attribute_table(&igraph_cattribute_table);
+
+    /* Create a graph, add some attributes and save it as a GraphML file. */
+    igraph_famous(&g, "Petersen");
+    SETGAS(&g, "name", "Petersen's graph");
+    SETGAN(&g, "vertices", igraph_vcount(&g));
+    SETGAN(&g, "edges", igraph_ecount(&g));
+    SETGAB(&g, "famous", true);
+
+    igraph_vector_init_range(&y, 1, igraph_vcount(&g) + 1);
+    SETVANV(&g, "id", &y);
+    igraph_vector_destroy(&y);
+
+    SETVAS(&g, "name", 0, "foo");
+    SETVAS(&g, "name", 1, "foobar");
+
+    SETVAB(&g, "is_first", 0, true);
+
+    igraph_vector_init_range(&y, 1, igraph_ecount(&g) + 1);
+    SETEANV(&g, "id", &y);
+    igraph_vector_destroy(&y);
+
+    SETEAS(&g, "name", 0, "FOO");
+    SETEAS(&g, "name", 1, "FOOBAR");
+
+    SETEAB(&g, "is_first", 0, true);
+
+    /* Turn off the warning handler temporarily because the GML writer will
+     * print warnings about boolean attributes being converted to numbers, and
+     * we don't care about these. */
+    oldwarnhandler = igraph_set_warning_handler(igraph_warning_handler_ignore);
+    igraph_write_graph_gml(&g, stdout, IGRAPH_WRITE_GML_DEFAULT_SW, 0, "");
+    igraph_set_warning_handler(oldwarnhandler);
+
+    /* Back to business. */
+    igraph_write_graph_graphml(&g, stdout, /*prefixattr=*/ true);
+
+    igraph_destroy(&g);
+
+    return 0;
+}