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 +1,67 @@
+/*
+   igraph library.
+   Copyright (C) 2006-2012  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 <math.h>
+
+int main(void) {
+
+    igraph_t g;
+    igraph_real_t res;
+
+    /* Initialize the library. */
+    igraph_setup();
+
+    /* Trivial cases */
+
+    igraph_ring(&g, 100, IGRAPH_UNDIRECTED, 0, 0);
+    igraph_reciprocity(&g, &res, 0, IGRAPH_RECIPROCITY_DEFAULT);
+    igraph_destroy(&g);
+
+    if (res != 1) {
+        return 1;
+    }
+
+    /* Small test graph */
+
+    igraph_small(&g, 0, IGRAPH_DIRECTED,
+                 0,  1,  0,  2,  0,  3,  1,  0,  2,  3,  3,  2, -1);
+
+    igraph_reciprocity(&g, &res, 0, IGRAPH_RECIPROCITY_RATIO);
+    igraph_destroy(&g);
+
+    if (res != 0.5) {
+        fprintf(stderr, "%f != %f\n", res, 0.5);
+        return 2;
+    }
+
+    igraph_small(&g, 0, IGRAPH_DIRECTED, 0, 1, 1, 2, 2, 1, -1);
+    igraph_reciprocity(&g, &res, 0, IGRAPH_RECIPROCITY_DEFAULT);
+    igraph_destroy(&g);
+
+    if (fabs(res - 2.0 / 3.0) > 1e-15) {
+        fprintf(stderr, "%f != %f\n", res, 2.0 / 3.0);
+        return 3;
+    }
+
+    return 0;
+}