HierarchicalClustering.h

#ifndef HIERARCHICAL_CLUSTERING_H
#define HIERARCHICAL_CLUSTERING_H

#include "statistics.h"

namespace Statistics {

class HierarchicalClustering
{
 public:
        struct distances
        {
                Real dist;
                int index;
        };

        // comparing operator for struct distances
        struct Cmp{
                bool operator()(const distances d1, const distances d2)
                        const 
                {
                        if(d1.dist == d2.dist)
                        {
                                return d1.index < d2.index;
                        }
                        return d1.dist < d2.dist;
                }
        };

        enum Type { SingleLinkage, CompleteLinkage, AverageLinkage };

        void Build(const std::vector<Vector>& data,int K,Type type = SingleLinkage);

        void Build(const Matrix& dist,int K,Type type = SingleLinkage);

        const std::vector<int>& Cluster(int i) const { return A[i]; }

        // 2d vector for storing lists of items in clusters
        std::vector<std::vector<int> > A;

};



} //namespace Statistics

#endif