gibbsOperator.h

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#ifndef GUM_GIBBS_OPERATOR_H
#define GUM_GIBBS_OPERATOR_H
 
#include <agrum/BN/IBayesNet.h>
 
namespace gum {

 
  template < typename GUM_SCALAR >
  class GibbsOperator {
    public:
    GibbsOperator(const IBayesNet< GUM_SCALAR >& BN,
                  const NodeProperty< Idx >*     hardEv,
                  Size                           nbr      = 1,
                  bool                           atRandom = false);

    virtual ~GibbsOperator();

    Size nbrDrawnVar() const { return nbr_; }
 
    void setNbrDrawnVar(Size nbr) { nbr_ = nbr; }
 
    bool isDrawnAtRandom() const { return atRandom_; }
 
    void setDrawnAtRandom(bool atRandom) { atRandom_ = atRandom; }

    Instantiation monteCarloSample();

    Instantiation nextSample(Instantiation prev);
 
    protected:
    Size                           counting_;
    const IBayesNet< GUM_SCALAR >& samplingBn_;
    const NodeProperty< Idx >*     hardEv_;
    Sequence< NodeId >             samplingNodes_;
 
    Size nbr_;
    bool atRandom_;
 
    void updateSamplingNodes_();
 
    private:
    // adds a node to current instantiation
    void _drawVarMonteCarlo_(NodeId nod, Instantiation* I);
 
    void _GibbsSample_(NodeId id, Instantiation* I);
  };
 
 
#ifndef GUM_NO_EXTERN_TEMPLATE_CLASS
 
  extern template class GibbsOperator< double >;
 
#endif
 
}   // namespace gum
 
#include <agrum/BN/inference/tools/gibbsOperator_tpl.h>
 
#endif