example.cpp

   1 /*  Copyright (C) 2006-2008  Joris Mooij  [j dot mooij at science dot ru dot nl]
   2     Radboud University Nijmegen, The Netherlands
   3
   4     This file is part of libDAI.
   5
   6     libDAI is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     libDAI is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with libDAI; if not, write to the Free Software
  18     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19 */
  20
  21
  22 #include <iostream>
  23 #include <dai/alldai.h>
  24
  25
  26 using namespace dai;
  27 using namespace std;
  28
  29
  30 int main( int argc, char *argv[] ) {
  31     if ( argc != 2 ) {
  32         cout << "Usage: " << argv[0] << " <filename.fg>" << endl << endl;
  33         cout << "Reads factor graph <filename.fg> and runs" << endl;
  34         cout << "Belief Propagation and JunctionTree on it." << endl << endl;
  35         return 1;
  36     } else {
  37         FactorGraph fg;
  38         fg.ReadFromFile(argv[1]);
  39
  40         size_t  maxiter = 10000;
  41         double  tol = 1e-9;
  42         size_t  verb = 1;
  43
  44         PropertySet opts;
  45         opts.Set("maxiter",maxiter);
  46         opts.Set("tol",tol);
  47         opts.Set("verbose",verb);
  48
  49         JTree jt( fg, opts("updates",string("HUGIN")) );
  50         jt.init();
  51         jt.run();
  52
  53         BP bp(fg, opts("updates",string("SEQFIX"))("logdomain",false));
  54         bp.init();
  55         bp.run();
  56
  57         cout << "Exact single node marginals:" << endl;
  58         for( size_t i = 0; i < fg.nrVars(); i++ )
  59             cout << jt.belief(fg.var(i)) << endl;
  60
  61         cout << "Approximate (loopy belief propagation) single node marginals:" << endl;
  62         for( size_t i = 0; i < fg.nrVars(); i++ )
  63             cout << bp.belief(fg.var(i)) << endl;
  64
  65         cout << "Exact factor marginals:" << endl;
  66         for( size_t I = 0; I < fg.nrFactors(); I++ )
  67             cout << jt.belief(fg.factor(I).vars()) << endl;
  68
  69         cout << "Approximate (loopy belief propagation) factor marginals:" << endl;
  70         for( size_t I = 0; I < fg.nrFactors(); I++ )
  71             cout << bp.belief(fg.factor(I).vars()) << "=" << bp.beliefF(I) << endl;
  72
  73         cout << "Exact log partition sum: " << jt.logZ() << endl;
  74         cout << "Approximate (loopy belief propagation) log partition sum: " << bp.logZ() << endl;
  75     }
  76
  77     return 0;
  78 }