First commit on github -- NetBunch 1.0

1 files changed, 162 insertions, 0 deletions

diff --git a/src/clust/clust.c b/src/clust/clust.c
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+++ b/src/clust/clust.c
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+/**
+ *  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 3 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
+ *  <http://www.gnu.org/licenses/>.
+ *
+ *  (c) Vincenzo Nicosia 2009-2017 -- <v.nicosia@qmul.ac.uk>
+ * 
+ *  This file is part of NetBunch, a package for complex network
+ *  analysis and modelling. For more information please visit:
+ *
+ *             http://www.complex-networks.net/
+ *
+ *  If you use this software, please add a reference to 
+ *
+ *               V. Latora, V. Nicosia, G. Russo             
+ *   "Complex Networks: Principles, Methods and Applications"
+ *              Cambridge University Press (2017) 
+ *                ISBN: 9781107103184
+ *
+ ***********************************************************************
+ *
+ *  This program computes the clustering coefficient of a graph and of
+ *  each node.
+ *
+ *
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "utils.h"
+
+
+void usage(char *argv[]){
+
+    printf("********************************************************************\n"
+         "**                                                                **\n"
+         "**                        -*-    clust   -*-                      **\n"
+         "**                                                                **\n"
+         "**   Compute the graph clustering coefficient and, optionally,    **\n"
+         "**   also the node clustering coefficient of all the nodes in     **\n"
+         "**   the graph 'graph_in'.                                        **\n"
+         "**                                                                **\n"
+         "**   The input file 'graph_in' is an edge-list:                   **\n"
+         "**                                                                **\n"
+         "**                            I_1 J_1                             **\n"
+         "**                            I_2 J_2                             **\n"
+         "**                            I_3 J_3                             **\n"
+         "**                            ... ...                             **\n"
+         "**                            I_K J_K                             **\n"
+         "**                                                                **\n"
+         "**    If 'graph_in' is equal to '-' (dash), read the file from    **\n" 
+         "**    the standard input (STDIN).                                 **\n"
+         "**                                                                **\n"
+         "**    The output is a single line containing the value of the     **\n"
+         "**    graph clustering coefficient of 'graph_in'.                 **\n"
+         "**                                                                **\n"
+         "**    If 'SHOW' is provided as second argument, the program       **\n"
+         "**    on the standard error (STDERR) the label, degree, and       **\n"
+         "**    node clustering coefficient of all the nodes of 'graph_in'  **\n"
+         "**    in the format:                                              **\n"
+         "**                                                                **\n"
+         "**      node_1 k_1 c_1                                            **\n"
+         "**      node_2 k_2 c_2                                            **\n"
+         "**      node_3 k_3 c_3                                            **\n"
+         "**      node_4 k_4 c_4                                            **\n"
+         "**      .....                                                     **\n"
+         "**                                                                **\n"
+         "**    where 'k_1' is the degree of 'node_1' and 'c_1' is its      **\n"
+         "**    node clustering coefficient. If a node has degree smaller   **\n"
+         "**    than 2, its clustering coefficient is equal to zero.        **\n"
+         "**                                                                **\n"
+         "********************************************************************\n"
+         " This is Free Software - You can use and distribute it under \n"
+         " the terms of the GNU General Public License, version 3 or later\n\n"
+         " Please visit http://www.complex-networks.net for more information\n\n"
+         " (c) Vincenzo Nicosia 2009-2017 (v.nicosia@qmul.ac.uk)\n"
+         "********************************************************************\n\n"
+         );
+  
+  printf("Usage: %s <graph_in> [SHOW]\n", argv[0]);
+}
+
+
+
+double avg_clust(unsigned int *J_slap, unsigned int *r_slap, unsigned int N, int show){
+
+  double c = 0, ci=0;
+  unsigned int i, j, l, ki;
+
+  for(i=0; i<N; i ++){/* for each node i..*/
+    ci = 0;
+    ki = r_slap[i+1] - r_slap[i];
+    for(j=r_slap[i]; j<r_slap[i+1]; j++){/*... pick a neighbour...*/
+      for (l=r_slap[J_slap[j]]; l<r_slap[J_slap[j]+1]; l++){
+        if (J_slap[l] != i){
+          /*...and check how many times it has a link to a neighbour of i */
+          if(is_neigh(J_slap, r_slap, N, i, J_slap[l])){
+            ci += 1;
+          }
+        }
+      }
+    }
+    if(ki > 1)
+      ci /= ki * (ki-1);
+    else
+      ci = 0;
+    if (show) 
+      fprintf(stderr, "%d %d %g\n", i, ki, ci);
+    c += ci;
+  }
+  c /= N;
+  return c;
+}
+
+
+
+
+int main(int argc, char *argv[]){
+
+  unsigned int *J_slap=NULL, *r_slap=NULL;
+  unsigned int K, N;
+  FILE *filein;
+  double c;
+  int show = 0;
+
+  if (argc < 2){
+    usage(argv);
+    exit(1);
+  }
+  
+  if (argc >2 && !my_strcasecmp("SHOW", argv[2])){
+    show = 1;
+  }
+
+  if (!strcmp(argv[1], "-")){
+    /* take the input from STDIN */
+    filein = stdin;
+  }
+  else {
+    filein = openfile_or_exit(argv[1], "r", 2);
+  }
+
+  read_slap(filein, &K, &N, &J_slap, &r_slap);
+  fclose(filein);
+  
+  c = avg_clust(J_slap, r_slap, N, show);
+  printf("%2.8lf\n", c);
+  free(J_slap);
+  free(r_slap);
+}