include/dai/evidence.h

   1 /*  Copyright (C) 2009  Charles Vaske  [cvaske at soe dot ucsc dot edu]
   2     University of California Santa Cruz
   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 /// \file
  23 /// \brief Defines classes Evidence and Observation
  24 /// \todo Improve documentation
  25
  26
  27 #ifndef __defined_libdai_evidence_h
  28 #define __defined_libdai_evidence_h
  29
  30
  31 #include <istream>
  32 #include <dai/daialg.h>
  33
  34
  35 namespace dai {
  36
  37
  38 /// Stores observed values of a subset of variables
  39 class Observation {
  40     private:
  41         std::map<Var, size_t> _obs;
  42
  43     public:
  44         /// Default constructor
  45         Observation() : _obs() {}
  46         /// Get all observations
  47         const std::map<Var, size_t>& observations() const { return _obs; }
  48         /// Add an observation
  49         void addObservation( Var node, size_t setting );
  50         /// Clamp variables to observed values
  51         void applyEvidence( InfAlg& alg ) const;
  52 };
  53
  54
  55 /// Stores multiple observations of variables
  56 class Evidence {
  57     private:
  58         std::vector<Observation> _samples;
  59
  60     public:
  61         /// Default constructor
  62         Evidence() : _samples() {}
  63
  64         /** Read in tab-data from a stream. Each line contains one sample, and
  65          *  the first line is a header line with names. The first column contains
  66          *  names for each of the samples.
  67          */
  68         void addEvidenceTabFile(std::istream& is, std::map<std::string, Var>& varMap);
  69
  70         /** Read in tab-data from a stream. Each line contains one sample,
  71          *  and the first line is a header line with variable IDs. The first
  72          *  column contains names for each of the samples.
  73          */
  74         void addEvidenceTabFile(std::istream& is, FactorGraph& fg);
  75
  76         /// Total number of samples in this evidence file
  77         size_t nrSamples() const { return _samples.size(); }
  78
  79         /// @name iterator interface
  80         //@{
  81         typedef std::vector<Observation>::iterator iterator;
  82         typedef std::vector<Observation>::const_iterator const_iterator;
  83
  84         iterator begin() { return _samples.begin(); }
  85         const_iterator begin() const { return _samples.begin(); }
  86         iterator end() { return _samples.end(); }
  87         const_iterator end() const { return _samples.end(); }
  88         //@}
  89 };
  90
  91
  92 } // end of namespace dai
  93
  94
  95 #endif