Tanl Linguistic Pipeline

tag/Tanlpos/Viterbi.h

/*
**  Tanl
**  tag/TanlPos/Viterbi.h
**  ----------------------------------------------------------------------
**  Copyright (c) 2005  Giuseppe Attardi (attardi@di.unipi.it).
**  ----------------------------------------------------------------------
**
**  This file is part of Tanl.
**
**  Tanl is free software; you can redistribute it and/or modify it
**  under the terms of the GNU General Public License, version 3,
**  as published by the Free Software Foundation.
**
**  Tanl 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/>.
**  ----------------------------------------------------------------------
*/

#ifndef Tanl_POS_viterbi_H
#define Tanl_POS_viterbi_H

#include "HMM.h"
#include "State.h"

using namespace std;

namespace Tanl { namespace POS {
    
class Viterbi
{
public:
  struct Node {
    Node() {}
    Node(State const& state, Node const* from = 0, double weight = 0) :
      state(state), from(from), weight(weight) { }

    State       state;          
    Node const* from;           
    double      weight;         
  };
    
  Viterbi(HMM& hmm) : hmm(hmm) { }
    
  std::vector<State> decode(double logtheta, State& startState,
                            HMM::Observations& observations);

private:
  void step_forward(double logtheta, std::vector<Node>& currentNodes,
                    HMM::Observation const& obs);

  HMM& hmm;
};

} // namespace POS
} // namespace Tanl

#endif // Tanl_POS_viterbi_H

 

Copyright © 2005-2011 G. Attardi. Generated on 4 Mar 2011 by doxygen 1.6.1.