include/dai/bp.h

   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 #ifndef __defined_libdai_bp_h
  23 #define __defined_libdai_bp_h
  24
  25
  26 #include <string>
  27 #include <dai/daialg.h>
  28 #include <dai/factorgraph.h>
  29 #include <dai/enum.h>
  30
  31
  32 namespace dai {
  33
  34
  35 class BP : public DAIAlgFG {
  36     protected:
  37         typedef std::vector<size_t> ind_t;
  38         struct EdgeProp {
  39             ind_t  index;
  40             Prob   message;
  41             Prob   newMessage;
  42             double residual;
  43         };
  44
  45         std::vector<std::vector<EdgeProp> > edges;
  46         bool logDomain;
  47
  48     public:
  49         ENUM4(UpdateType,SEQFIX,SEQRND,SEQMAX,PARALL)
  50         UpdateType Updates() const { return GetPropertyAs<UpdateType>("updates"); }
  51
  52         // default constructor
  53         BP() : DAIAlgFG(), edges(), logDomain(false) {};
  54         // copy constructor
  55         BP(const BP & x) : DAIAlgFG(x), edges(x.edges), logDomain(x.logDomain) {};
  56         BP* clone() const { return new BP(*this); }
  57         // construct BP object from FactorGraph
  58         BP(const FactorGraph & fg, const Properties &opts) : DAIAlgFG(fg, opts), edges(), logDomain(false) {
  59             assert( checkProperties() );
  60             create();
  61         }
  62         // assignment operator
  63         BP & operator=(const BP & x) {
  64             if(this!=&x) {
  65                 DAIAlgFG::operator=(x);
  66                 edges = x.edges;
  67                 logDomain = x.logDomain;
  68             }
  69             return *this;
  70         }
  71
  72         static const char *Name;
  73
  74         Prob & message(size_t i, size_t _I) { return edges[i][_I].message; }
  75         const Prob & message(size_t i, size_t _I) const { return edges[i][_I].message; }
  76         Prob & newMessage(size_t i, size_t _I) { return edges[i][_I].newMessage; }
  77         const Prob & newMessage(size_t i, size_t _I) const { return edges[i][_I].newMessage; }
  78         ind_t & index(size_t i, size_t _I) { return edges[i][_I].index; }
  79         const ind_t & index(size_t i, size_t _I) const { return edges[i][_I].index; }
  80         double & residual(size_t i, size_t _I) { return edges[i][_I].residual; }
  81         const double & residual(size_t i, size_t _I) const { return edges[i][_I].residual; }
  82         void findMaxResidual( size_t &i, size_t &_I );
  83
  84         std::string identify() const;
  85         void create();
  86         void init();
  87         void calcNewMessage( size_t i, size_t _I );
  88         double run();
  89         Factor beliefV (size_t i) const;
  90         Factor beliefF (size_t I) const;
  91         Factor belief (const Var &n) const;
  92         Factor belief (const VarSet &n) const;
  93         std::vector<Factor> beliefs() const;
  94         Real logZ() const;
  95
  96         void init( const VarSet &ns );
  97         void undoProbs( const VarSet &ns ) { FactorGraph::undoProbs(ns); init(ns); }
  98         bool checkProperties();
  99 };
 100
 101
 102 } // end of namespace dai
 103
 104
 105 #endif