DiscreteHiddenMarkovModel.h

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#ifndef GRT_DISCRETE_HIDDEN_MARKOV_MODEL_HEADER
#define GRT_DISCRETE_HIDDEN_MARKOV_MODEL_HEADER

#include "HMMEnums.h"
#include "../../Util/GRTCommon.h"
#include "../../CoreModules/MLBase.h"

GRT_BEGIN_NAMESPACE

//This class is used for the HMM batch training
class HMMTrainingObject{
public:
 HMMTrainingObject(){
  pk = 0.0;
 }
 ~HMMTrainingObject(){}
 MatrixFloat alpha;     //The forward estimate matrix
 MatrixFloat beta;      //The backward estimate matrix
 VectorFloat c;         //The scaling coefficient Vector
 Float pk;    //P( O | Model )
};

class DiscreteHiddenMarkovModel : public MLBase {

public:
 DiscreteHiddenMarkovModel();

 DiscreteHiddenMarkovModel(const UINT numStates,const UINT numSymbols,const UINT modelType,const UINT delta);
    
 DiscreteHiddenMarkovModel(const MatrixFloat &a,const MatrixFloat &b,const VectorFloat &pi,const UINT modelType,const UINT delta);
    
    DiscreteHiddenMarkovModel(const DiscreteHiddenMarkovModel &rhs);
    
    virtual ~DiscreteHiddenMarkovModel();
    
    Float predict(const UINT newSample);
    Float predict(const Vector<UINT> &obs);
    
    bool resetModel(const UINT numStates,const UINT numSymbols,const UINT modelType,const UINT delta);
    bool train(const Vector< Vector<UINT> > &trainingData);
    
    virtual bool reset();
    
    virtual bool saveModelToFile( std::fstream &file ) const;
    
    virtual bool loadModelFromFile( std::fstream &file );

    bool randomizeMatrices(const UINT numStates,const UINT numSymbols);
 Float predictLogLikelihood(const Vector<UINT> &obs);
 bool forwardBackward(HMMTrainingObject &trainingObject,const Vector<UINT> &obs);
    bool train_(const Vector< Vector<UINT> > &obs,const UINT maxIter, UINT &currentIter,Float &newLoglikelihood);
    virtual bool print() const;
    
    VectorFloat getTrainingIterationLog() const;
    
 UINT numStates;             //The number of states for this model
 UINT numSymbols;            //The number of symbols for this model
 MatrixFloat a;             //The transitions probability matrix
 MatrixFloat b;             //The emissions probability matrix
 VectorFloat pi;            //The state start probability Vector
    VectorFloat trainingIterationLog;   //Stores the loglikelihood at each iteration the BaumWelch algorithm

 UINT modelType;
 UINT delta;    //The number of states a model can move to in a LeftRight model
 UINT numRandomTrainingIterations;  //The number of training loops to find the best starting values
 Float logLikelihood; //The log likelihood of an observation sequence given the modal, calculated by the forward method
 Float cThreshold;  //The classification threshold for this model
    CircularBuffer<UINT> observationSequence;
    Vector< UINT > estimatedStates;
};

GRT_END_NAMESPACE

#endif //GRT_HIDDEN_MARKOV_MODEL_HEADER