GBRForestD.h

Go to the documentation of this file.

#ifndef EGAMMAOBJECTS_GBRForestD
#define EGAMMAOBJECTS_GBRForestD

//                                                                      //
// GBRForestD                                                           //
//                                                                      //
// A fast minimal implementation of Gradient-Boosted Regression Trees   //
// which has been especially optimized for size on disk and in memory.  //                                                                  
//                                                                      //
// Designed to be built from the output of GBRLikelihood,               //
// but could also be  generalized to otherwise-trained trees            //
// classification, or other boosting methods in the future              //
//                                                                      //
//  Josh Bendavid - CERN                                                //

#include "CondFormats/Serialization/interface/Serializable.h"

#include <vector>
#include "GBRTreeD.h"
#include <math.h>
#include <stdio.h>
#include "Rtypes.h"

class GBRForestD {
  public:
    typedef GBRTreeD TreeT;
    
    GBRForestD();
    template<typename InputForestT> GBRForestD(const InputForestT &forest);
    virtual ~GBRForestD();

    double GetResponse(const float* vector) const;

    double InitialResponse() const { return fInitialResponse; }
    void SetInitialResponse(double response) { fInitialResponse = response; }

    std::vector<GBRTreeD> &Trees() { return fTrees; }
    const std::vector<GBRTreeD> &Trees() const { return fTrees; }

  protected:
    double fInitialResponse;
    std::vector<GBRTreeD> fTrees;  
  
  COND_SERIALIZABLE;  
};

//_______________________________________________________________________
inline double GBRForestD::GetResponse(const float* vector) const {
  double response = fInitialResponse;
  for (std::vector<GBRTreeD>::const_iterator it=fTrees.begin(); it!=fTrees.end(); ++it) {
    int termidx = it->TerminalIndex(vector);
    response += it->GetResponse(termidx);
  }    
  return response;
}

//_______________________________________________________________________
template<typename InputForestT> GBRForestD::GBRForestD(const InputForestT &forest) : 
 fInitialResponse(forest.InitialResponse()) {
  //templated constructor to allow construction from Forest classes in GBRLikelihood
  //without creating an explicit dependency
  
  for (typename std::vector<typename InputForestT::TreeT>::const_iterator treeit = forest.Trees().begin(); treeit!=forest.Trees().end(); ++treeit) {
    fTrees.push_back(GBRTreeD(*treeit));
  }
  
}



#endif