/data/refman/pasoursint/CMSSW_5_3_3/src/RecoEcal/EgammaClusterAlgos/src/HybridClusterAlgo.cc

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#include "RecoEcal/EgammaClusterAlgos/interface/HybridClusterAlgo.h"
#include "RecoCaloTools/Navigation/interface/EcalBarrelNavigator.h"
#include "DataFormats/GeometryVector/interface/GlobalPoint.h"
#include "Geometry/CaloGeometry/interface/CaloCellGeometry.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include <iostream>
#include <map>
#include <vector>
#include <set>
#include "RecoEcal/EgammaCoreTools/interface/ClusterEtLess.h"
#include "RecoLocalCalo/EcalRecAlgos/interface/EcalSeverityLevelAlgo.h"


//The real constructor
HybridClusterAlgo::HybridClusterAlgo(double eb_str, 
                                     int step, 
                                     double ethres,
                                     double eseed,
                                     double xi,
                                     bool useEtForXi,
                                     double ewing,
                                     std::vector<int> v_chstatus,
                                     const PositionCalc& posCalculator,
                                     bool dynamicEThres,
                                     double eThresA,
                                     double eThresB,
                                     std::vector<int> severityToExclude,
                                     bool excludeFromCluster
                                     ) :
  
  eb_st(eb_str), phiSteps_(step), 
  eThres_(ethres), eThresA_(eThresA), eThresB_(eThresB),
  Eseed(eseed), Xi(xi), UseEtForXi(useEtForXi), Ewing(ewing), 
  dynamicEThres_(dynamicEThres),
  v_chstatus_(v_chstatus), v_severitylevel_(severityToExclude),
  //severityRecHitThreshold_(severityRecHitThreshold),
  //severitySpikeThreshold_(severitySpikeThreshold),
  excludeFromCluster_(excludeFromCluster)
  
  
{

  dynamicPhiRoad_ = false;
  LogTrace("EcalClusters") << "dynamicEThres: " << dynamicEThres_ << " : A,B " << eThresA_ << ", " << eThresB_;
  LogTrace("EcalClusters") << "Eseed: " << Eseed << " , Xi: " << Xi << ", UseEtForXi: " << UseEtForXi;
  
  //if (dynamicPhiRoad_) phiRoadAlgo_ = new BremRecoveryPhiRoadAlgo(bremRecoveryPset);
  posCalculator_ = posCalculator;
  topo_ = new EcalBarrelHardcodedTopology();
  
  std::sort( v_chstatus_.begin(), v_chstatus_.end() );
  
  
}

// Return a vector of clusters from a collection of EcalRecHits:
void HybridClusterAlgo::makeClusters(const EcalRecHitCollection*recColl, 
                                     const CaloSubdetectorGeometry*geometry,
                                     reco::BasicClusterCollection &basicClusters,
                                     const EcalSeverityLevelAlgo * sevLv,
                                     bool regional,
                                     const std::vector<EcalEtaPhiRegion>& regions
                                     )
{
  //clear vector of seeds
  seeds.clear();
  //clear flagged crystals
  excludedCrys_.clear();
  //clear map of supercluster/basiccluster association
  clustered_.clear();
  //clear set of used detids
  useddetids.clear();
  //clear vector of seed clusters
  seedClus_.clear();
  //Pass in a pointer to the collection.
  recHits_ = recColl;
  
  LogTrace("EcalClusters") << "Cleared vectors, starting clusterization..." ;
  LogTrace("EcalClusters") << " Purple monkey aardvark." ;
  //
  
  int nregions=0;
  if(regional) nregions=regions.size();
  
  if(!regional || nregions) {
    
    EcalRecHitCollection::const_iterator it;
    
    for (it = recHits_->begin(); it != recHits_->end(); it++){
      
      //Make the vector of seeds that we're going to use.
      //One of the few places position is used, needed for ET calculation.    
      const CaloCellGeometry *this_cell = (*geometry).getGeometry(it->id());
      GlobalPoint position = this_cell->getPosition();
      
      
      // Require that RecHit is within clustering region in case
      // of regional reconstruction
      bool withinRegion = false;
      if (regional) {
        std::vector<EcalEtaPhiRegion>::const_iterator region;
        for (region=regions.begin(); region!=regions.end(); region++) {
          if (region->inRegion(position)) {
            withinRegion =  true;
            break;
          }
        }
      }
      
      if (!regional || withinRegion) {

        //Must pass seed threshold
        float ET = it->energy() * sin(position.theta());

        LogTrace("EcalClusters") << "Seed crystal: " ;

        if (ET > eb_st) {
          // avoid seeding for anomalous channels (recoFlag based)
          uint32_t rhFlag = (*it).recoFlag();
          LogTrace("EcalClusters") << "rhFlag: " << rhFlag ;
         ;
          std::vector<int>::const_iterator vit = std::find( v_chstatus_.begin(), v_chstatus_.end(), rhFlag );
          if ( vit != v_chstatus_.end() ){
            if (excludeFromCluster_)
              excludedCrys_.insert(it->id());
            continue; // the recHit has to be excluded from seeding
          }

          int severityFlag =  sevLv->severityLevel( it->id(), *recHits_);
          std::vector<int>::const_iterator sit = std::find( v_severitylevel_.begin(), v_severitylevel_.end(), severityFlag);
          LogTrace("EcalClusters") << "found flag: " << severityFlag ;
           
          
          if (sit!=v_severitylevel_.end()){ 
            if (excludeFromCluster_)
              excludedCrys_.insert(it->id());
            continue;
          }
          seeds.push_back(*it);
         
          LogTrace("EcalClusters") << "Seed ET: " << ET ;
          LogTrace("EcalClsuters") << "Seed E: " << it->energy() ;
        }
      }
    }
    
  }
  
  
  //Yay sorting.
  LogTrace("EcalClusters") << "Built vector of seeds, about to sort them..." ;
  
  //Needs three argument sort with seed comparison operator
  sort(seeds.begin(), seeds.end(), less_mag());
  
  LogTrace("EcalClusters") << "done" ;
  
  //Now to do the work.
  LogTrace("EcalClusters") << "About to call mainSearch...";
  mainSearch(recColl,geometry);
  LogTrace("EcalClusters") << "done" ;
  
  //Hand the basicclusters back to the producer.  It has to 
  //put them in the event.  Then we can make superclusters.
  std::map<int, reco::BasicClusterCollection>::iterator bic; 
  for (bic= clustered_.begin();bic!=clustered_.end();bic++){
    reco::BasicClusterCollection bl = bic->second;
    for (int j=0;j<int(bl.size());++j){
      basicClusters.push_back(bl[j]);
    }
  }
  
  //Yay more sorting.
  sort(basicClusters.rbegin(), basicClusters.rend(), ClusterEtLess() );
  //Done!
  LogTrace("EcalClusters") << "returning to producer. ";
  
}


void HybridClusterAlgo::mainSearch(const EcalRecHitCollection* hits, const CaloSubdetectorGeometry*geometry)
{
  LogTrace("EcalClusters") << "HybridClusterAlgo Algorithm - looking for clusters" ;
  LogTrace("EcalClusters") << "Found the following clusters:" ;
        
        // Loop over seeds:
        std::vector<EcalRecHit>::iterator it;
        int clustercounter=0;

        for (it = seeds.begin(); it != seeds.end(); it++){
                std::vector <reco::BasicCluster> thisseedClusters;
                DetId itID = it->id();

                // make sure the current seed has not been used/will not be used in the future:
                std::set<DetId>::iterator seed_in_rechits_it = useddetids.find(itID);

                if (seed_in_rechits_it != useddetids.end()) continue;
                //If this seed is already used, then don't use it again.

                // output some info on the hit:
                LogTrace("EcalClusters") << "*****************************************************" << "Seed of energy E = " << it->energy() << " @ " << EBDetId(itID) << "*****************************************************" ;
                

                //Make a navigator, and set it to the seed cell.
                EcalBarrelNavigator navigator(itID, topo_);

                //Now use the navigator to start building dominoes.

                //Walking positive in phi:
                std::vector <double> dominoEnergyPhiPlus;  //Here I will store the results of the domino sums
                std::vector <std::vector <EcalRecHit> > dominoCellsPhiPlus; //These are the actual EcalRecHit for dominos.

                //Walking negative in phi
                std::vector <double> dominoEnergyPhiMinus;  //Here I will store the results of the domino sums
                std::vector <std::vector <EcalRecHit> > dominoCellsPhiMinus; //These are the actual EcalRecHit for dominos.

                //The two sets together.
                std::vector <double> dominoEnergy;  //Here I will store the results of the domino sums
                std::vector <std::vector <EcalRecHit> > dominoCells; //These are the actual EcalRecHit for dominos.

                //First, the domino about the seed:
                std::vector <EcalRecHit> initialdomino;
                double e_init = makeDomino(navigator, initialdomino);
        if (e_init < Eseed) continue;

        LogTrace("EcalClusters") << "Made initial domino" ;
        
                //
                // compute the phi road length
                double phiSteps;
                double et5x5 = et25(navigator, hits, geometry);
                if (dynamicPhiRoad_ && e_init > 0)
                {
                        phiSteps = phiRoadAlgo_->barrelPhiRoad(et5x5);
                        navigator.home();
                } else phiSteps = phiSteps_;

                //Positive phi steps.
                for (int i=0;i<phiSteps;++i){
                        //remember, this always increments the current position of the navigator.
                        DetId centerD = navigator.north();
                        if (centerD.null())
                                continue;
                        LogTrace("EcalClusters") << "Step ++" << i << " @ " << EBDetId(centerD) ;
                        EcalBarrelNavigator dominoNav(centerD, topo_);

                        //Go get the new domino.
                        std::vector <EcalRecHit> dcells;
                        double etemp = makeDomino(dominoNav, dcells);

                        //save this information
                        dominoEnergyPhiPlus.push_back(etemp);
                        dominoCellsPhiPlus.push_back(dcells);
                }
                LogTrace("EcalClusters") << "Got positive dominos" ;
                //return to initial position
                navigator.home();

                //Negative phi steps.
                for (int i=0;i<phiSteps;++i){
                        //remember, this always decrements the current position of the navigator.
                        DetId centerD = navigator.south();
                        if (centerD.null())
                                continue;

                        LogTrace("EcalClusters") << "Step --" << i << " @ " << EBDetId(centerD) ;
                        EcalBarrelNavigator dominoNav(centerD, topo_);

                        //Go get the new domino.
                        std::vector <EcalRecHit> dcells;
                        double etemp = makeDomino(dominoNav, dcells);

                        //save this information
                        dominoEnergyPhiMinus.push_back(etemp);
                        dominoCellsPhiMinus.push_back(dcells);
                }
                
                LogTrace("EcalClusters") << "Got negative dominos: " ;
        
                //Assemble this information:
                for (int i=int(dominoEnergyPhiMinus.size())-1;i >= 0;--i){
                        dominoEnergy.push_back(dominoEnergyPhiMinus[i]);
                        dominoCells.push_back(dominoCellsPhiMinus[i]);
                }
                dominoEnergy.push_back(e_init);
                dominoCells.push_back(initialdomino);
                for (int i=0;i<int(dominoEnergyPhiPlus.size());++i){
                        dominoEnergy.push_back(dominoEnergyPhiPlus[i]);
                        dominoCells.push_back(dominoCellsPhiPlus[i]);
                }

                //Ok, now I have all I need in order to go ahead and make clusters.
                LogTrace("EcalClusters") << "Dumping domino energies: " ;
                

                //for (int i=0;i<int(dominoEnergy.size());++i){
                //       LogTrace("EcalClusters") << "Domino: " << i << " E: " << dominoEnergy[i] ;
                //      }
                //Identify the peaks in this set of dominos:
                //Peak==a domino whose energy is greater than the two adjacent dominos.
                //thus a peak in the local sense.
                double etToE(1.);
                if(!UseEtForXi){
                  etToE = 1./e2Et(navigator, hits, geometry);
                }
                std::vector <int> PeakIndex;
                for (int i=1;i<int(dominoEnergy.size())-1;++i){
                        if (dominoEnergy[i] > dominoEnergy[i-1]
                                        && dominoEnergy[i] >= dominoEnergy[i+1]
                            && dominoEnergy[i] > sqrt( Eseed*Eseed + Xi*Xi*et5x5*et5x5*etToE*etToE) )
                          { // Eseed increases ~proportiaonally to et5x5
                            PeakIndex.push_back(i);
                          }
                }

                LogTrace("EcalClusters") << "Found: " << PeakIndex.size() << " peaks." ;
        
                //Order these peaks by energy:
                for (int i=0;i<int(PeakIndex.size());++i){
                        for (int j=0;j<int(PeakIndex.size())-1;++j){
                                if (dominoEnergy[PeakIndex[j]] < dominoEnergy[PeakIndex[j+1]]){
                                        int ihold = PeakIndex[j+1];
                                        PeakIndex[j+1] = PeakIndex[j];
                                        PeakIndex[j] = ihold;
                                }
                        }
                }

                std::vector<int> OwnerShip;
                std::vector<double> LumpEnergy;
                for (int i=0;i<int(dominoEnergy.size());++i) OwnerShip.push_back(-1);

                //Loop over peaks.  
                double eThres = eThres_;
                double e5x5 = 0.0;
                for (int i = 0; i < int(PeakIndex.size()); ++i)
                {

                        int idxPeak = PeakIndex[i];
                        OwnerShip[idxPeak] = i;
                        double lump = dominoEnergy[idxPeak];

                        // compute eThres for this peak
                        // if set to dynamic (otherwise uncanged from
                        // fixed setting
                        if (dynamicEThres_) {

                                //std::cout << "i : " << i << " idxPeak " << idxPeak << std::endl;
                                //std::cout << "    the dominoEnergy.size() = " << dominoEnergy.size() << std::endl;
                                // compute e5x5 for this seed crystal
                                //std::cout << "idxPeak, phiSteps " << idxPeak << ", " << phiSteps << std::endl;
                                e5x5 = lump;
                                //std::cout << "lump " << e5x5 << std::endl;
                                if ((idxPeak + 1) < (int)dominoEnergy.size()) e5x5 += dominoEnergy[idxPeak + 1];
                                //std::cout << "+1 " << e5x5 << std::endl;
                                if ((idxPeak + 2) < (int)dominoEnergy.size()) e5x5 += dominoEnergy[idxPeak + 2];
                                //std::cout << "+2 " << e5x5 << std::endl;
                                if ((idxPeak - 1) > 0) e5x5 += dominoEnergy[idxPeak - 1];
                                //std::cout << "-1 " << e5x5 << std::endl;
                                if ((idxPeak - 2) > 0) e5x5 += dominoEnergy[idxPeak - 2];
                                //std::cout << "-2 " << e5x5 << std::endl;
                                // compute eThres
                                eThres = (eThresA_ * e5x5) + eThresB_;   
                                //std::cout << eThres << std::endl;
                                //std::cout << std::endl;
                        }

                        //Loop over adjacent dominos at higher phi
                        for (int j=idxPeak+1;j<int(dominoEnergy.size());++j){
                                if (OwnerShip[j]==-1 && 
                                                dominoEnergy[j] > eThres
                                                && dominoEnergy[j] <= dominoEnergy[j-1]){
                                        OwnerShip[j]= i;
                                        lump+=dominoEnergy[j];
                                }
                                else{
                                        break;
                                }
                        }
                        //loop over adjacent dominos at lower phi.  Sum up energy of lumps.
                        for (int j=idxPeak-1;j>=0;--j){
                                if (OwnerShip[j]==-1 && 
                                                dominoEnergy[j] > eThres
                                                && dominoEnergy[j] <= dominoEnergy[j+1]){
                                        OwnerShip[j]= i;
                                        lump+=dominoEnergy[j];
                                }
                                else{
                                        break;
                                }
                        }
                        LumpEnergy.push_back(lump);
                }

                //Make the basic clusters:
                for (int i=0;i<int(PeakIndex.size());++i){
                        bool HasSeedCrystal = false;
                        //One cluster for each peak.
                        std::vector<EcalRecHit> recHits;
                        std::vector< std::pair<DetId, float> > dets;
                        int nhits=0;
                        for (int j=0;j<int(dominoEnergy.size());++j){   
                                if (OwnerShip[j] == i){
                                        std::vector <EcalRecHit> temp = dominoCells[j];
                                        for (int k=0;k<int(temp.size());++k){
                                                dets.push_back( std::pair<DetId, float>(temp[k].id(), 1.) ); // by default energy fractions are 1
                                                if (temp[k].id()==itID)
                                                        HasSeedCrystal = true;
                                                recHits.push_back(temp[k]);
                                                nhits++;
                                        }
                                }  
                        }
                        LogTrace("EcalClusters") << "Adding a cluster with: " << nhits;
                        LogTrace("EcalClusters") << "total E: " << LumpEnergy[i];
                        LogTrace("EcalClusters") << "total dets: " << dets.size() ;
        
                        //Get Calorimeter position
                        Point pos = posCalculator_.Calculate_Location(dets,hits,geometry);

                        //double totChi2=0;
                        //double totE=0;
                        std::vector<std::pair<DetId, float> > usedHits;
                        for (int blarg=0;blarg<int(recHits.size());++blarg){
                                //totChi2 +=0;
                                //totE+=recHits[blarg].energy();
                                usedHits.push_back(std::make_pair<DetId, float>(recHits[blarg].id(), 1.0));
                                useddetids.insert(recHits[blarg].id());
                        }

                        //if (totE>0)
                        //totChi2/=totE;

                        if (HasSeedCrystal) {
                                // note that this "basiccluster" has the seed crystal of the hyrbid, so record it
                                seedClus_.push_back(reco::BasicCluster(LumpEnergy[i], pos, 
                                        reco::CaloID(reco::CaloID::DET_ECAL_BARREL), usedHits, 
                                        reco::CaloCluster::hybrid, itID));
                                // and also add to the vector of clusters that will be used in constructing
                                // the supercluster
                                thisseedClusters.push_back(reco::BasicCluster(LumpEnergy[i], pos,                                                               reco::CaloID(reco::CaloID::DET_ECAL_BARREL), 
                                     usedHits, reco::CaloCluster::hybrid, itID));
                        }
                        else {
                                // note that if this "basiccluster" is not the one that seeded the hybrid, 
                                // the seed crystal is unset in this entry in the vector of clusters that will
                                // be used in constructing the super cluster
                                thisseedClusters.push_back(reco::BasicCluster(LumpEnergy[i], pos,                                                               reco::CaloID(reco::CaloID::DET_ECAL_BARREL), 
                                     usedHits, reco::CaloCluster::hybrid));
                        }
                }


                // Make association so that superclusters can be made later.
                // but only if some BasicClusters have been found...
                if (thisseedClusters.size() > 0) 
                {
                        clustered_.insert(std::make_pair(clustercounter, thisseedClusters));
                        clustercounter++;
                }
        }//Seed loop

}// end of mainSearch

reco::SuperClusterCollection HybridClusterAlgo::makeSuperClusters(const reco::CaloClusterPtrVector& clustersCollection)
{
        //Here's what we'll return.
        reco::SuperClusterCollection SCcoll;

        //Here's our map iterator that gives us the appropriate association.
        std::map<int, reco::BasicClusterCollection>::iterator mapit;
        for (mapit = clustered_.begin();mapit!=clustered_.end();mapit++){

                reco::CaloClusterPtrVector thissc;
                reco::CaloClusterPtr seed;//This is not really a seed, but I need to tell SuperCluster something.
                //So I choose the highest energy basiccluster in the SuperCluster.

                std::vector <reco::BasicCluster> thiscoll = mapit->second; //This is the set of BasicClusters in this
                //SuperCluster

                double ClusterE = 0; //Sum of cluster energies for supercluster.
                //Holders for position of this supercluster.
                double posX=0;
                double posY=0;
                double posZ=0;

                //Loop over this set of basic clusters, find their references, and add them to the
                //supercluster.  This could be somehow more efficient.

                for (int i=0;i<int(thiscoll.size());++i){
                        reco::BasicCluster thisclus = thiscoll[i]; //The Cluster in question.
                        for (int j=0;j<int(clustersCollection.size());++j){
                                //Find the appropriate cluster from the list of references
                                reco::BasicCluster cluster_p = *clustersCollection[j];
                                if (thisclus== cluster_p){ //Comparison based on energy right now.
                                        thissc.push_back(clustersCollection[j]);
                                        bool isSeed = false;
                                        for (int qu=0;qu<int(seedClus_.size());++qu){
                                                if (cluster_p == seedClus_[qu])
                                                        isSeed = true;
                                        }
                                        if (isSeed) seed = clustersCollection[j];

                                        ClusterE += cluster_p.energy();
                                        posX += cluster_p.energy() * cluster_p.position().X();
                                        posY += cluster_p.energy() * cluster_p.position().Y();
                                        posZ += cluster_p.energy() * cluster_p.position().Z();

                                }
                        }//End loop over finding references.
                }//End loop over clusters.

                posX /= ClusterE;
                posY /= ClusterE;
                posZ /= ClusterE;

                /* //This part is moved to EgammaSCEnergyCorrectionAlgo
                   double preshowerE = 0.;
                   double phiWidth = 0.;
                   double etaWidth = 0.;
                //Calculate phiWidth & etaWidth for SuperClusters
                reco::SuperCluster suCl(ClusterE, math::XYZPoint(posX, posY, posZ), seed, thissc, preshowerE, phiWidth, etaWidth);
                SCShape_->Calculate_Covariances(suCl);
                phiWidth = SCShape_->phiWidth();
                etaWidth = SCShape_->etaWidth();
                //Assign phiWidth & etaWidth to SuperCluster as data members
                suCl.setPhiWidth(phiWidth);
                suCl.setEtaWidth(etaWidth);
                 */

                reco::SuperCluster suCl(ClusterE, math::XYZPoint(posX, posY, posZ), seed, thissc);
                SCcoll.push_back(suCl);

                LogTrace("EcalClusters") << "Super cluster sum: " << ClusterE ;
                LogTrace("EcalClusters") << "Made supercluster with energy E: " << suCl.energy() ;
                
        }//end loop over map
        sort(SCcoll.rbegin(), SCcoll.rend(), ClusterEtLess());
        return SCcoll;
}

double HybridClusterAlgo::makeDomino(EcalBarrelNavigator &navigator, std::vector <EcalRecHit> &cells)
{
        //At the beginning of this function, the navigator starts at the middle of the domino,
        //and that's where EcalBarrelNavigator::home() should send it.
        //Walk one crystal in eta to either side of the initial point.  Sum the three cell energies.
        //If the resultant energy is larger than Ewing, then go an additional cell to either side.
        //Returns:  Total domino energy.  Also, stores the cells used to create domino in the vector.
        cells.clear();
        double Etot = 0;

        //Ready?  Get the starting cell.
        DetId center = navigator.pos();
        EcalRecHitCollection::const_iterator center_it = recHits_->find(center);

        if (center_it!=recHits_->end()){
                EcalRecHit SeedHit = *center_it;
                if (useddetids.find(center) == useddetids.end() && excludedCrys_.find(center)==excludedCrys_.end()){ 
                        Etot += SeedHit.energy();
                        cells.push_back(SeedHit);
                }
        }
        //One step upwards in Ieta:
        DetId ieta1 = navigator.west();
        EcalRecHitCollection::const_iterator eta1_it = recHits_->find(ieta1);
        if (eta1_it !=recHits_->end()){
                EcalRecHit UpEta = *eta1_it;
                if (useddetids.find(ieta1) == useddetids.end() && excludedCrys_.find(ieta1)==excludedCrys_.end()){
                        Etot+=UpEta.energy();
                        cells.push_back(UpEta);
                }
        }

        //Go back to the middle.
        navigator.home();

        //One step downwards in Ieta:
        DetId ieta2 = navigator.east();
        EcalRecHitCollection::const_iterator eta2_it = recHits_->find(ieta2);
        if (eta2_it !=recHits_->end()){
                EcalRecHit DownEta = *eta2_it;
                if (useddetids.find(ieta2)==useddetids.end() && excludedCrys_.find(ieta2)==excludedCrys_.end()){
                        Etot+=DownEta.energy();
                        cells.push_back(DownEta);
                }
        }

        //Now check the energy.  If smaller than Ewing, then we're done.  If greater than Ewing, we have to
        //add two additional cells, the 'wings'
        if (Etot < Ewing) {
                navigator.home(); //Needed even here!!
                return Etot;  //Done!  Not adding 'wings'.
        }

        //Add the extra 'wing' cells.  Remember, we haven't sent the navigator home,
        //we're still on the DownEta cell.
        if (ieta2 != DetId(0)){
                DetId ieta3 = navigator.east(); //Take another step downward.
                EcalRecHitCollection::const_iterator eta3_it = recHits_->find(ieta3);
                if (eta3_it != recHits_->end()){
                        EcalRecHit DownEta2 = *eta3_it;
                        if (useddetids.find(ieta3)==useddetids.end() && excludedCrys_.find(ieta3)==excludedCrys_.end()){
                                Etot+=DownEta2.energy();
                                cells.push_back(DownEta2);
                        }
                }
        }
        //Now send the navigator home.
        navigator.home();
        navigator.west(); //Now you're on eta1_it
        if (ieta1 != DetId(0)){
                DetId ieta4 = navigator.west(); //Take another step upward.
                EcalRecHitCollection::const_iterator eta4_it = recHits_->find(ieta4);
                if (eta4_it != recHits_->end()){
                        EcalRecHit UpEta2 = *eta4_it;
                        if (useddetids.find(ieta4) == useddetids.end() && excludedCrys_.find(ieta4)==excludedCrys_.end()){
                                Etot+=UpEta2.energy();
                                cells.push_back(UpEta2);
                        }
                }
        }
        navigator.home();
        return Etot;
}

double HybridClusterAlgo::et25(EcalBarrelNavigator &navigator, 
                const EcalRecHitCollection *hits, 
                const CaloSubdetectorGeometry *geometry)
{

        DetId thisDet;
        std::vector< std::pair<DetId, float> > dets;
        dets.clear();
        EcalRecHitCollection::const_iterator hit;
        double energySum = 0.0;

        for (int dx = -2; dx < 3; ++dx)
        {
                for (int dy = -2; dy < 3; ++ dy)
                {
                        //std::cout << "dx, dy " << dx << ", " << dy << std::endl;
                        thisDet = navigator.offsetBy(dx, dy);
                        navigator.home();

                        if (thisDet != DetId(0))
                        {
                                hit = recHits_->find(thisDet);
                                if (hit != recHits_->end()) 
                                {
                                        dets.push_back( std::pair<DetId, float>(thisDet, 1.) ); // by default hit energy fraction is set to 1
                                        energySum += hit->energy();
                                }
                        }
                }
        }

        // convert it to ET
        //std::cout << "dets.size(), energySum: " << dets.size() << ", " << energySum << std::endl;
        Point pos = posCalculator_.Calculate_Location(dets, hits, geometry);
        double et = energySum/cosh(pos.eta());
        return et;

}


double HybridClusterAlgo::e2Et(EcalBarrelNavigator &navigator, 
                                const EcalRecHitCollection *hits, 
                                const CaloSubdetectorGeometry *geometry)
{
  
  DetId thisDet;
  std::vector< std::pair<DetId, float> > dets;
  dets.clear();
  EcalRecHitCollection::const_iterator hit;
  
  for (int dx = -2; dx < 3; ++dx)
    {
      for (int dy = -2; dy < 3; ++ dy)
        {
          thisDet = navigator.offsetBy(dx, dy);
          navigator.home();
          
          if (thisDet != DetId(0))
            {
              hit = recHits_->find(thisDet);
              if (hit != recHits_->end()) 
                {
                  dets.push_back( std::pair<DetId, float>(thisDet, 1.) ); // by default hit energy fraction is set to 1
                }
            }
        }
    }
  
  // compute coefficient to turn E into Et 
  Point pos = posCalculator_.Calculate_Location(dets, hits, geometry);
  return  1/cosh(pos.eta());

}