/** 
* @file SpectralCluster.h
* @brief spectral clustering by kmeans-clustering of eigenvectors
* @author Erik Rodner
* @date 11/13/2007

*/
#ifndef SPECTRALCLUSTERINCLUDE
#define SPECTRALCLUSTERINCLUDE

#include "core/vector/VectorT.h"
#include "core/vector/MatrixT.h"

#include "ClusterAlgorithm.h"
#include "KMeans.h"


namespace OBJREC {

/** spectral clustering by kmeans-clustering of eigenvectors */
class SpectralCluster : public ClusterAlgorithm
{

    protected:
	int noClasses;
	double alpha;

	KMeans kmeans;

	enum {
	    L_UNNORMALIZED  = 0,
	    L_RW_NORMALIZED 
	};

	virtual void computeLaplacian ( const NICE::VVector & features,
					 // refactor-nice.pl: check this substitution
					 // old: Matrix & laplacian,
					 NICE::Matrix & laplacian,
					 int method, double alpha );


	virtual void getSimilarityMatrix ( const NICE::VVector & features, 
					    // refactor-nice.pl: check this substitution
					    // old: Matrix & laplacian, double alpha );
					    NICE::Matrix & laplacian, double alpha );
    public:
  
	/** simple constructor */
	SpectralCluster (int _noClasses, double alpha);
      
	/** simple destructor */
	virtual ~SpectralCluster();
     
	void cluster ( const NICE::VVector & features,
		       NICE::VVector & prototypes,
		       std::vector<double> & weights,
		       std::vector<int>    & assignment );

};


} // namespace

#endif