loopyBeliefPropagation.h

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#ifndef GUM_LOOPYBELIEFPROPAGATION_H
#define GUM_LOOPYBELIEFPROPAGATION_H
 
#include <agrum/BN/inference/tools/approximateInference.h>
 
namespace gum {
  template < GUM_Numeric GUM_SCALAR >
  class LoopyBeliefPropagation: public ApproximateInference< GUM_SCALAR > {
    public:
    explicit LoopyBeliefPropagation(const IBayesNet< GUM_SCALAR >* bn);

    ~LoopyBeliefPropagation() override;
 
    protected:
    void onStateChanged_() override;
 
    void onEvidenceAdded_(const NodeId id, bool isHardEvidence) override;
 
    void onEvidenceErased_(const NodeId id, bool isHardEvidence) override;
 
    void onAllEvidenceErased_(bool contains_hard_evidence) override;
 
    void onEvidenceChanged_(const NodeId id, bool hasChangedSoftHard) override;
 
    void onModelChanged_(const GraphicalModel* bn) override;
 
    void updateOutdatedStructure_() override;
 
    void updateOutdatedTensors_() override;
 
    void onMarginalTargetAdded_(const NodeId id) override;
 
    void onMarginalTargetErased_(const NodeId id) override;
 
    void onAllMarginalTargetsAdded_() override;
 
    void onAllMarginalTargetsErased_() override;


    const Tensor< GUM_SCALAR >& posterior_(NodeId id) override;
 
    void makeInference_() override;
 
    // will be used in both directions :
    // for x->y, (x,y) and (y,x) will be in  _messages_
    ArcProperty< Tensor< GUM_SCALAR > >  _messages_;
    NodeProperty< Tensor< GUM_SCALAR > > _posteriors_;
 
    void _initStats_();
 
    void                 _init_messages_();
    Tensor< GUM_SCALAR > _computeProdPi_(NodeId X);
    Tensor< GUM_SCALAR > _computeProdPi_(NodeId X, NodeId except);
    Tensor< GUM_SCALAR > _computeProdLambda_(NodeId X);
    Tensor< GUM_SCALAR > _computeProdLambda_(NodeId X, NodeId except);
 
    // return the max differential BNdistance for this node
    GUM_SCALAR _updateNodeMessage_(NodeId X);
  };
 
#ifndef GUM_NO_EXTERN_TEMPLATE_CLASS
#  ifndef GUM_NO_EXTERN_TEMPLATE_CLASS
  // extern template class LoopyBeliefPropagation<float>;
#  endif
#endif
#ifndef GUM_NO_EXTERN_TEMPLATE_CLASS
#  ifndef GUM_NO_EXTERN_TEMPLATE_CLASS
  // extern template class LoopyBeliefPropagation<double>;
#  endif
#endif
} /* namespace gum */
 
#include <agrum/BN/inference/loopyBeliefPropagation_tpl.h>
 
 
#endif   // GUM_LOOPYBELIEFPROPAGATION_H