PFRecHitProducerHCAL.cc

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#include "RecoParticleFlow/PFClusterProducer/plugins/PFRecHitProducerHCAL.h"

#include <memory>

#include "DataFormats/ParticleFlowReco/interface/PFRecHit.h"

#include "DataFormats/HcalRecHit/interface/HFRecHit.h"
#include "DataFormats/HcalRecHit/interface/HBHERecHit.h"
#include "DataFormats/HcalRecHit/interface/HcalRecHitCollections.h"
#include "DataFormats/HcalDetId/interface/HcalSubdetector.h"

#include "DataFormats/DetId/interface/DetId.h"
#include "DataFormats/EcalDetId/interface/EEDetId.h"
#include "DataFormats/EcalDetId/interface/EBDetId.h"

#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/Framework/interface/ESHandle.h"
#include "FWCore/Framework/interface/EventSetup.h"


#include "Geometry/CaloGeometry/interface/CaloSubdetectorGeometry.h"
#include "Geometry/CaloGeometry/interface/CaloGeometry.h"
#include "Geometry/CaloGeometry/interface/CaloCellGeometry.h"
#include "Geometry/CaloGeometry/interface/TruncatedPyramid.h"
#include "Geometry/Records/interface/CaloGeometryRecord.h"

#include "Geometry/CaloTopology/interface/HcalTopology.h"
#include "RecoCaloTools/Navigation/interface/CaloNavigator.h"

#include "DataFormats/CaloTowers/interface/CaloTowerCollection.h"

#include "Geometry/CaloTopology/interface/CaloTowerTopology.h"
#include "RecoCaloTools/Navigation/interface/CaloTowerNavigator.h"

#include "RecoLocalCalo/HcalRecAlgos/interface/HcalCaloFlagLabels.h"


using namespace std;
using namespace edm;

PFRecHitProducerHCAL::PFRecHitProducerHCAL(const edm::ParameterSet& iConfig)
  : PFRecHitProducer( iConfig ) 
{

 

  // access to the collections of rechits 

  
  inputTagHcalRecHitsHBHE_ =
    iConfig.getParameter<InputTag>("hcalRecHitsHBHE");
    
  inputTagHcalRecHitsHF_ =
    iConfig.getParameter<InputTag>("hcalRecHitsHF");
    
 
  inputTagCaloTowers_ = 
    iConfig.getParameter<InputTag>("caloTowers");
   
  thresh_HF_ = 
    iConfig.getParameter<double>("thresh_HF");
  navigation_HF_ = 
    iConfig.getParameter<bool>("navigation_HF");
  weight_HFem_ =
    iConfig.getParameter<double>("weight_HFem");
  weight_HFhad_ =
    iConfig.getParameter<double>("weight_HFhad");

  HCAL_Calib_ =
    iConfig.getParameter<bool>("HCAL_Calib");
  HF_Calib_ =
    iConfig.getParameter<bool>("HF_Calib");
  HCAL_Calib_29 = 
    iConfig.getParameter<double>("HCAL_Calib_29");
  HF_Calib_29 = 
    iConfig.getParameter<double>("HF_Calib_29");

  shortFibre_Cut = iConfig.getParameter<double>("ShortFibre_Cut");
  longFibre_Fraction = iConfig.getParameter<double>("LongFibre_Fraction");

  longFibre_Cut = iConfig.getParameter<double>("LongFibre_Cut");
  shortFibre_Fraction = iConfig.getParameter<double>("ShortFibre_Fraction");

  applyLongShortDPG_ = iConfig.getParameter<bool>("ApplyLongShortDPG");

  longShortFibre_Cut = iConfig.getParameter<double>("LongShortFibre_Cut");
  minShortTiming_Cut = iConfig.getParameter<double>("MinShortTiming_Cut");
  maxShortTiming_Cut = iConfig.getParameter<double>("MaxShortTiming_Cut");
  minLongTiming_Cut = iConfig.getParameter<double>("MinLongTiming_Cut");
  maxLongTiming_Cut = iConfig.getParameter<double>("MaxLongTiming_Cut");

  applyTimeDPG_ = iConfig.getParameter<bool>("ApplyTimeDPG");
  applyPulseDPG_ = iConfig.getParameter<bool>("ApplyPulseDPG");

  ECAL_Compensate_ = iConfig.getParameter<bool>("ECAL_Compensate");
  ECAL_Threshold_ = iConfig.getParameter<double>("ECAL_Threshold");
  ECAL_Compensation_ = iConfig.getParameter<double>("ECAL_Compensation");
  ECAL_Dead_Code_ = iConfig.getParameter<unsigned int>("ECAL_Dead_Code");

  EM_Depth_ = iConfig.getParameter<double>("EM_Depth");
  HAD_Depth_ = iConfig.getParameter<double>("HAD_Depth");

  //--ab
  produces<reco::PFRecHitCollection>("HFHAD").setBranchAlias("HFHADRecHits");
  produces<reco::PFRecHitCollection>("HFEM").setBranchAlias("HFEMRecHits");
  //--ab
}



PFRecHitProducerHCAL::~PFRecHitProducerHCAL() {}



void PFRecHitProducerHCAL::createRecHits(vector<reco::PFRecHit>& rechits,
                     vector<reco::PFRecHit>& rechitsCleaned,
                     edm::Event& iEvent, 
                     const edm::EventSetup& iSetup ) {

  
  // this map is necessary to find the rechit neighbours efficiently
  //C but I should think about using Florian's hashed index to do this.
  //C in which case the map might not be necessary anymore
  //C however the hashed index does not seem to be implemented for HCAL
  // 
  // the key of this map is detId. 
  // the value is the index in the rechits vector
  map<unsigned,  unsigned > idSortedRecHits;
  map<unsigned,  unsigned > idSortedRecHitsHFEM;
  map<unsigned,  unsigned > idSortedRecHitsHFHAD;
  typedef map<unsigned, unsigned >::iterator IDH;  


  edm::ESHandle<CaloGeometry> geoHandle;
  iSetup.get<CaloGeometryRecord>().get(geoHandle);
  
  // get the hcalBarrel geometry
  const CaloSubdetectorGeometry *hcalBarrelGeometry = 
    geoHandle->getSubdetectorGeometry(DetId::Hcal, HcalBarrel);

  // get the endcap geometry
  const CaloSubdetectorGeometry *hcalEndcapGeometry = 
    geoHandle->getSubdetectorGeometry(DetId::Hcal, HcalEndcap);

  //--ab
  auto_ptr< vector<reco::PFRecHit> > HFHADRecHits( new vector<reco::PFRecHit> ); 
  auto_ptr< vector<reco::PFRecHit> > HFEMRecHits( new vector<reco::PFRecHit> ); 
  //--ab

  // 2 possibilities to make HCAL clustering :
  // - from the HCAL rechits
  // - from the CaloTowers. 
  // ultimately, clustering will be done taking CaloTowers as an 
  // input. This possibility is currently under investigation, and 
  // was thus made optional.

  // in the first step, we will fill the map of PFRecHits hcalrechits
  // either from CaloTowers or from HCAL rechits. 

  // in the second step, we will perform clustering on this map.

  if( !(inputTagCaloTowers_ == InputTag()) ) {
      
    edm::Handle<CaloTowerCollection> caloTowers; 
    CaloTowerTopology caloTowerTopology; 
    const CaloSubdetectorGeometry *caloTowerGeometry = 0; 
    // = geometry_->getSubdetectorGeometry(id)

    // get calotowers
    bool found = iEvent.getByLabel(inputTagCaloTowers_,
                   caloTowers);

    if(!found) {
      ostringstream err;
      err<<"could not find rechits "<<inputTagCaloTowers_;
      LogError("PFRecHitProducerHCAL")<<err.str()<<endl;
    
      throw cms::Exception( "MissingProduct", err.str());
    }
    else {
      assert( caloTowers.isValid() );

      // get HF rechits
      edm::Handle<HFRecHitCollection>  hfHandle;  
      found = iEvent.getByLabel(inputTagHcalRecHitsHF_,
                hfHandle);
      
      if(!found) {
    ostringstream err;
    err<<"could not find HF rechits "<<inputTagHcalRecHitsHF_;
    LogError("PFRecHitProducerHCAL")<<err.str()<<endl;
    
    throw cms::Exception( "MissingProduct", err.str());
      }
      else {
    assert( hfHandle.isValid() );
      }
      
      // get HBHE rechits
      edm::Handle<HBHERecHitCollection>  hbheHandle;  
      found = iEvent.getByLabel(inputTagHcalRecHitsHBHE_,
                hbheHandle);
      
      if(!found) {
    ostringstream err;
    err<<"could not find HBHE rechits "<<inputTagHcalRecHitsHBHE_;
    LogError("PFRecHitProducerHCAL")<<err.str()<<endl;
    
    throw cms::Exception( "MissingProduct", err.str());
      }
      else {
    assert( hbheHandle.isValid() );
      }
      
      // create rechits
      typedef CaloTowerCollection::const_iterator ICT;
    
      for(ICT ict=caloTowers->begin(); ict!=caloTowers->end();ict++) {
      
    const CaloTower& ct = (*ict);
      
    //C 
    if(!caloTowerGeometry) 
      caloTowerGeometry = geoHandle->getSubdetectorGeometry(ct.id());

      
    // get the hadronic energy.
    
    // Mike: Just ask for the Hadronic part only now!
    // Patrick : ARGH ! While this is ok for the HCAL, this is 
    // just wrong for the HF (in which em/had are artificially 
    // separated. 
    double energy = ct.hadEnergy();
    //Auguste: Photons in HF have no hadEnergy in fastsim: -> all RecHit collections are empty with photons.
    double energyEM = ct.emEnergy(); // For HF !
    //so test the total energy to deal with the photons in  HF:
    if( (energy+energyEM) < 1e-9 ) continue;
      
    assert( ct.constituentsSize() );      
    //Mike: The DetId will be taken by the first Hadronic constituent
    //         of the tower. That is only what we need

    
    //get the constituents of the tower
    const std::vector<DetId>& hits = ct.constituents();
    const std::vector<DetId>& allConstituents = theTowerConstituentsMap->constituentsOf(ct.id());

    /*
    for(unsigned int i=0;i< hits.size();++i) {
      if(hits[i].det()==DetId::Hcal) {
        HcalDetId did = hits[i];
        if ( did.subdet()==HcalEndcap || did.subdet()==HcalForward ) { 
          //double en = hits[i].energy();
          int ieta = did.ieta();
          const CaloCellGeometry *thisCell = hcalEndcapGeometry->getGeometry(did);
          const GlobalPoint& position = thisCell->getPosition();
          if ( abs(ieta) > 27 && abs(ieta) < 33 && energy > 10. ) { 
        std::cout << "HE/HF hit " << i << " at eta = " << ieta 
              << " with CT energy = " << energy 
              << " at eta, z (hit) = " << position.eta() << " " << position.z()
              << " at eta, z (cte) = " << ct.emPosition().eta() << " " << ct.emPosition().z()
              << " at eta, z (cth) = " << ct.hadPosition().eta() << " " << ct.hadPosition().z()
              << " at eta, z (cto) = " << ct.eta() << " " << ct.vz() 
              << std::endl;
          }
        }
      }
    }
    */
    
    //Reserve the DetId we are looking for:

    HcalDetId detid;
    // EcalDetId edetid;
    bool foundHCALConstituent = false;

 
    //Loop on the calotower constituents and search for HCAL
    double dead = 0.;
    double alive = 0.;
    for(unsigned int i=0;i< hits.size();++i) {
      if(hits[i].det()==DetId::Hcal) { 
        foundHCALConstituent = true;
        detid = hits[i];
        // An HCAL tower was found: Look for dead ECAL channels in the same CaloTower.
        if ( ECAL_Compensate_ && energy > ECAL_Threshold_ ) {
          for(unsigned int j=0;j<allConstituents.size();++j) { 
        if ( allConstituents[j].det()==DetId::Ecal ) { 
          alive += 1.;
          EcalChannelStatus::const_iterator chIt = theEcalChStatus->find(allConstituents[j]);
          unsigned int dbStatus = chIt != theEcalChStatus->end() ? chIt->getStatusCode() : 0;
          if ( dbStatus > ECAL_Dead_Code_ ) dead += 1.;
        }
          }
        } 
        // Protection: tower 29 in HF is merged with tower 30. 
        // Just take the position of tower 30 in that case. 
        if ( detid.subdet() == HcalForward && abs(detid.ieta()) == 29 ) continue; 
        break;
      }
    }

    // In case of dead ECAL channel, rescale the HCAL energy...
    double rescaleFactor = alive > 0. ? 1. + ECAL_Compensation_*dead/alive : 1.;
      
    reco::PFRecHit* pfrh = 0;
    reco::PFRecHit* pfrhCleaned = 0;
    //---ab: need 2 rechits for the HF:
    reco::PFRecHit* pfrhHFEM = 0;
    reco::PFRecHit* pfrhHFHAD = 0;
    reco::PFRecHit* pfrhHFEMCleaned = 0;
    reco::PFRecHit* pfrhHFHADCleaned = 0;
    reco::PFRecHit* pfrhHFEMCleaned29 = 0;
    reco::PFRecHit* pfrhHFHADCleaned29 = 0;

    if(foundHCALConstituent)
      {
        // std::cout << ", new Energy = " << energy << std::endl;
        switch( detid.subdet() ) {
        case HcalBarrel: 
          {
        if(energy < thresh_Barrel_ ) continue;

        /*
        // Check the timing
        if ( energy > 5. ) { 
          for(unsigned int i=0;i< hits.size();++i) {
            if( hits[i].det() != DetId::Hcal ) continue; 
            HcalDetId theDetId = hits[i]; 
            typedef HBHERecHitCollection::const_iterator iHBHE;
            iHBHE theHit = hbheHandle->find(theDetId); 
            if ( theHit != hbheHandle->end() ) 
              std::cout << "HCAL hit : " 
                << theDetId.ieta() << " " << theDetId.iphi() << " " 
                << theHit->energy() << " " << theHit->time() << std::endl;
          }
        }
        */


        // if ( HCAL_Calib_ ) energy   *= std::min(max_Calib_,myPFCorr->getValues(detid)->getValue());
        //if ( rescaleFactor > 1. ) 
        // std::cout << "Barrel HCAL energy rescaled from = " << energy << " to " << energy*rescaleFactor << std::endl;
        if ( rescaleFactor > 1. ) { 
          pfrhCleaned = createHcalRecHit( detid, 
                          energy, 
                          PFLayer::HCAL_BARREL1, 
                          hcalBarrelGeometry,
                          ct.id().rawId() );
          pfrhCleaned->setRescale(rescaleFactor);
          energy *= rescaleFactor;
        }
        pfrh = createHcalRecHit( detid, 
                     energy, 
                 PFLayer::HCAL_BARREL1, 
                     hcalBarrelGeometry,
                     ct.id().rawId() );
        pfrh->setRescale(rescaleFactor);
          }
          break;
        case HcalEndcap:
          {
        if(energy < thresh_Endcap_ ) continue;

        /*
        // Check the timing
        if ( energy > 5. ) { 
          for(unsigned int i=0;i< hits.size();++i) {
            if( hits[i].det() != DetId::Hcal ) continue; 
            HcalDetId theDetId = hits[i]; 
            typedef HBHERecHitCollection::const_iterator iHBHE;
            iHBHE theHit = hbheHandle->find(theDetId); 
            if ( theHit != hbheHandle->end() ) 
              std::cout << "HCAL hit : " 
                << theDetId.ieta() << " " << theDetId.iphi() << " " 
                << theHit->energy() << " " << theHit->time() << std::endl;
          }
        }
        */

        // Apply tower 29 calibration
        if ( HCAL_Calib_ && abs(detid.ieta()) == 29 ) energy *= HCAL_Calib_29;
        //if ( rescaleFactor > 1. ) 
        // std::cout << "End-cap HCAL energy rescaled from = " << energy << " to " << energy*rescaleFactor << std::endl;
        if ( rescaleFactor > 1. ) { 
          pfrhCleaned = createHcalRecHit( detid, 
                          energy, 
                          PFLayer::HCAL_ENDCAP, 
                          hcalEndcapGeometry,
                          ct.id().rawId() );
          pfrhCleaned->setRescale(rescaleFactor);
          energy *= rescaleFactor;
        }
        pfrh = createHcalRecHit( detid, 
                     energy, 
                     PFLayer::HCAL_ENDCAP, 
                     hcalEndcapGeometry,
                     ct.id().rawId() );
        pfrh->setRescale(rescaleFactor);
          }
          break;
        case HcalOuter:
          {
          }
          break;
        case HcalForward:
          {
        //---ab: 2 rechits for HF:
        //double energyemHF = weight_HFem_*ct.emEnergy();
        //double energyhadHF = weight_HFhad_*ct.hadEnergy();
        double energyemHF = weight_HFem_ * energyEM;
        double energyhadHF = weight_HFhad_ * energy;
        // Some energy in the tower !
        if((energyemHF+energyhadHF) < thresh_HF_ ) continue;

        // Some cleaning in the HF 
        double longFibre = energyemHF + energyhadHF/2.;
        double shortFibre = energyhadHF/2.;
        int ieta = detid.ieta();
        int iphi = detid.iphi();
        HcalDetId theLongDetId (HcalForward, ieta, iphi, 1);
        HcalDetId theShortDetId (HcalForward, ieta, iphi, 2);
        typedef HFRecHitCollection::const_iterator iHF;
        iHF theLongHit = hfHandle->find(theLongDetId); 
        iHF theShortHit = hfHandle->find(theShortDetId); 
        // 
        double theLongHitEnergy = 0.;
        double theShortHitEnergy = 0.;
        bool flagShortDPG =  false; 
        bool flagLongDPG = false; 
        bool flagShortTimeDPG = false; 
        bool flagLongTimeDPG = false;
        bool flagShortPulseDPG = false;
        bool flagLongPulseDPG = false;
        //
        if ( theLongHit != hfHandle->end() ) { 
          theLongHitEnergy = theLongHit->energy();
          flagLongDPG = applyLongShortDPG_ && theLongHit->flagField(HcalCaloFlagLabels::HFLongShort)==1;
          flagLongTimeDPG = applyTimeDPG_ && theLongHit->flagField(HcalCaloFlagLabels::HFInTimeWindow)==1;
          flagLongPulseDPG = applyPulseDPG_ && theLongHit->flagField(HcalCaloFlagLabels::HFDigiTime)==1;
        }
        //
        if ( theShortHit != hfHandle->end() ) { 
          theShortHitEnergy = theShortHit->energy();
          flagShortDPG =  applyLongShortDPG_ && theShortHit->flagField(HcalCaloFlagLabels::HFLongShort)==1;
          flagShortTimeDPG = applyTimeDPG_ && theShortHit->flagField(HcalCaloFlagLabels::HFInTimeWindow)==1;
          flagShortPulseDPG = applyPulseDPG_ && theShortHit->flagField(HcalCaloFlagLabels::HFDigiTime)==1;
        }

        // Then check the timing in short and long fibres in all other towers.
        if ( theShortHitEnergy > longShortFibre_Cut && 
             ( theShortHit->time() < minShortTiming_Cut ||
               theShortHit->time() > maxShortTiming_Cut || 
               flagShortTimeDPG || flagShortPulseDPG ) ) { 
          // rescaleFactor = 0. ;
          pfrhHFHADCleaned = createHcalRecHit( detid, 
                               theShortHitEnergy, 
                               PFLayer::HF_HAD, 
                               hcalEndcapGeometry,
                               ct.id().rawId() );
          pfrhHFHADCleaned->setRescale(theShortHit->time());
          /*
          std::cout << "ieta/iphi = " << ieta << " " << iphi 
                << ", Energy em/had/long/short = " 
                << energyemHF << " " << energyhadHF << " "
                << theLongHitEnergy << " " << theShortHitEnergy << " " 
                << ". Time = " << theShortHit->time() << " " 
                << ". The short and long flags : " 
                << flagShortDPG << " " << flagLongDPG << " "  
                << flagShortTimeDPG << " " << flagLongTimeDPG << " "  
                << flagShortPulseDPG << " " << flagLongPulseDPG << " "  
                << ". Short fibres were cleaned." << std::endl;
          */
          shortFibre -= theShortHitEnergy;
          theShortHitEnergy = 0.;
        }
        
        
        if ( theLongHitEnergy > longShortFibre_Cut && 
             ( theLongHit->time() < minLongTiming_Cut ||
               theLongHit->time() > maxLongTiming_Cut  || 
               flagLongTimeDPG || flagLongPulseDPG ) ) { 
          //rescaleFactor = 0. ;
          pfrhHFEMCleaned = createHcalRecHit( detid, 
                              theLongHitEnergy, 
                              PFLayer::HF_EM, 
                              hcalEndcapGeometry,
                              ct.id().rawId() );
          pfrhHFEMCleaned->setRescale(theLongHit->time());
          /*
          std::cout << "ieta/iphi = " << ieta << " " << iphi 
                << ", Energy em/had/long/short = " 
                << energyemHF << " " << energyhadHF << " "
                << theLongHitEnergy << " " << theShortHitEnergy << " " 
                << ". Time = " << theLongHit->time() << " " 
                << ". The short and long flags : " 
                << flagShortDPG << " " << flagLongDPG << " "  
                << flagShortTimeDPG << " " << flagLongTimeDPG << " "  
                << flagShortPulseDPG << " " << flagLongPulseDPG << " "  
                << ". Long fibres were cleaned." << std::endl;
          */
          longFibre -= theLongHitEnergy;
          theLongHitEnergy = 0.;
        }

        // Some energy must be in the long fibres is there is some energy in the short fibres ! 
        if ( theShortHitEnergy > shortFibre_Cut && 
             ( theLongHitEnergy/theShortHitEnergy < longFibre_Fraction || 
               flagShortDPG ) ) {
          // Check if the long-fibre hit was not cleaned already (because hot)
          // In this case don't apply the cleaning
          const HcalChannelStatus* theStatus = theHcalChStatus->getValues(theLongDetId);
          unsigned theStatusValue = theStatus->getValue();
          // The channel is killed
          if ( !theStatusValue ) { 
            // rescaleFactor = 0. ;
            pfrhHFHADCleaned = createHcalRecHit( detid, 
                             theShortHitEnergy, 
                             PFLayer::HF_HAD, 
                             hcalEndcapGeometry,
                             ct.id().rawId() );
            pfrhHFHADCleaned->setRescale(theShortHit->time());
            /*
            std::cout << "ieta/iphi = " << ieta << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". Time = " << theShortHit->time() << " " 
                  << ". The status value is " << theStatusValue
                  << ". The short and long flags : " 
                  << flagShortDPG << " " << flagLongDPG << " "  
                  << flagShortTimeDPG << " " << flagLongTimeDPG << " "  
                  << flagShortPulseDPG << " " << flagLongPulseDPG << " "  
                  << ". Short fibres were cleaned." << std::endl;
            */
            shortFibre -= theShortHitEnergy;
            theShortHitEnergy = 0.;
          }
        }

        if ( theLongHitEnergy > longFibre_Cut && 
             ( theShortHitEnergy/theLongHitEnergy < shortFibre_Fraction || 
               flagLongDPG ) ) {
          // Check if the long-fibre hit was not cleaned already (because hot)
          // In this case don't apply the cleaning
          const HcalChannelStatus* theStatus = theHcalChStatus->getValues(theShortDetId);
          unsigned theStatusValue = theStatus->getValue();
          // The channel is killed
          if ( !theStatusValue ) { 
            //rescaleFactor = 0. ;
            pfrhHFEMCleaned = createHcalRecHit( detid, 
                              theLongHitEnergy, 
                              PFLayer::HF_EM, 
                              hcalEndcapGeometry,
                              ct.id().rawId() );
            pfrhHFEMCleaned->setRescale(theLongHit->time());
            /*
            std::cout << "ieta/iphi = " << ieta << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". The status value is " << theStatusValue
                  << ". Time = " << theLongHit->time() << " " 
                  << ". The short and long flags : " 
                  << flagShortDPG << " " << flagLongDPG << " "  
                  << flagShortTimeDPG << " " << flagLongTimeDPG << " "  
                  << flagShortPulseDPG << " " << flagLongPulseDPG << " "  
                  << ". Long fibres were cleaned." << std::endl;
            */
            longFibre -= theLongHitEnergy;
            theLongHitEnergy = 0.;
          }
        }

        // Special treatment for tower 29
        // A tower with energy only at ieta = +/- 29 is not physical -> Clean
        if ( abs(ieta) == 29 ) { 
          // rescaleFactor = 0. ;
          // Clean long fibres
          if ( theLongHitEnergy > shortFibre_Cut/2. ) { 
            pfrhHFEMCleaned29 = createHcalRecHit( detid, 
                              theLongHitEnergy, 
                              PFLayer::HF_EM, 
                              hcalEndcapGeometry,
                              ct.id().rawId() );
            pfrhHFEMCleaned29->setRescale(theLongHit->time());
            /*
            std::cout << "ieta/iphi = " << ieta << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". Long fibres were cleaned." << std::endl;
            */
            longFibre -= theLongHitEnergy;
            theLongHitEnergy = 0.;
          }
          // Clean short fibres
          if ( theShortHitEnergy > shortFibre_Cut/2. ) { 
            pfrhHFHADCleaned29 = createHcalRecHit( detid, 
                               theShortHitEnergy, 
                               PFLayer::HF_HAD, 
                               hcalEndcapGeometry,
                               ct.id().rawId() );
            pfrhHFHADCleaned29->setRescale(theShortHit->time());
            /*
            std::cout << "ieta/iphi = " << ieta << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". Short fibres were cleaned." << std::endl;
            */
            shortFibre -= theShortHitEnergy;
            theShortHitEnergy = 0.;
          }
        }
        // Check the timing of the long and short fibre rechits
        
        // First, check the timing of long and short fibre in eta = 29 if tower 30.
        else if ( abs(ieta) == 30 ) { 
          int ieta29 = ieta > 0 ? 29 : -29;
          HcalDetId theLongDetId29 (HcalForward, ieta29, iphi, 1);
          HcalDetId theShortDetId29 (HcalForward, ieta29, iphi, 2);
          iHF theLongHit29 = hfHandle->find(theLongDetId29); 
          iHF theShortHit29 = hfHandle->find(theShortDetId29); 
          // 
          double theLongHitEnergy29 = 0.;
          double theShortHitEnergy29 = 0.;
          bool flagShortDPG29 =  false; 
          bool flagLongDPG29 = false; 
          bool flagShortTimeDPG29 = false; 
          bool flagLongTimeDPG29 = false;
          bool flagShortPulseDPG29 = false;
          bool flagLongPulseDPG29 = false;
          //
          if ( theLongHit29 != hfHandle->end() ) {          
            theLongHitEnergy29 = theLongHit29->energy() ;
            flagLongDPG29 = applyLongShortDPG_ && theLongHit29->flagField(HcalCaloFlagLabels::HFLongShort)==1;
            flagLongTimeDPG29 = applyTimeDPG_ && theLongHit29->flagField(HcalCaloFlagLabels::HFInTimeWindow)==1;
            flagLongPulseDPG29 = applyPulseDPG_ && theLongHit29->flagField(HcalCaloFlagLabels::HFDigiTime)==1;
          }
          //
          if ( theShortHit29 != hfHandle->end() ) {             
            theShortHitEnergy29 = theShortHit29->energy();        
            flagShortDPG29 = applyLongShortDPG_ && theShortHit29->flagField(HcalCaloFlagLabels::HFLongShort)==1;
            flagShortTimeDPG29 = applyTimeDPG_ && theShortHit29->flagField(HcalCaloFlagLabels::HFInTimeWindow)==1;
            flagShortPulseDPG29 = applyPulseDPG_ && theShortHit29->flagField(HcalCaloFlagLabels::HFDigiTime)==1;
          }

          if ( theLongHitEnergy29 > longShortFibre_Cut && 
               ( theLongHit29->time() < minLongTiming_Cut ||
                 theLongHit29->time() > maxLongTiming_Cut ||
             flagLongTimeDPG29 || flagLongPulseDPG29 ) ) { 
            //rescaleFactor = 0. ;
            pfrhHFEMCleaned29 = createHcalRecHit( detid, 
                              theLongHitEnergy29, 
                              PFLayer::HF_EM, 
                              hcalEndcapGeometry,
                              ct.id().rawId() );
            pfrhHFEMCleaned29->setRescale(theLongHit29->time());
            /*
            std::cout << "ieta/iphi = " << ieta29 << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy29 << " " << theShortHitEnergy29 << " " 
                  << ". Time = " << theLongHit29->time() << " " 
                  << ". The short and long flags : " 
                  << flagShortDPG29 << " " << flagLongDPG29 << " "  
                  << flagShortTimeDPG29 << " " << flagLongTimeDPG29 << " "  
                  << flagShortPulseDPG29 << " " << flagLongPulseDPG29 << " "  
                  << ". Long fibres were cleaned." << std::endl;
            */
            longFibre -= theLongHitEnergy29;
            theLongHitEnergy29 = 0;
          }

          if ( theShortHitEnergy29 > longShortFibre_Cut && 
               ( theShortHit29->time() < minShortTiming_Cut ||
                 theShortHit29->time() > maxShortTiming_Cut ||
             flagShortTimeDPG29 || flagShortPulseDPG29 ) ) { 
            //rescaleFactor = 0. ;
            pfrhHFHADCleaned29 = createHcalRecHit( detid, 
                             theShortHitEnergy29, 
                             PFLayer::HF_HAD, 
                             hcalEndcapGeometry,
                             ct.id().rawId() );
            pfrhHFHADCleaned29->setRescale(theShortHit29->time());
            /*
            std::cout << "ieta/iphi = " << ieta29 << " " << iphi 
                  << ", Energy em/had/long/short = " 
                  << energyemHF << " " << energyhadHF << " "
                  << theLongHitEnergy29 << " " << theShortHitEnergy29 << " " 
                  << ". Time = " << theShortHit29->time() << " " 
                  << ". The short and long flags : " 
                  << flagShortDPG29 << " " << flagLongDPG29 << " "  
                  << flagShortTimeDPG29 << " " << flagLongTimeDPG29 << " "  
                  << flagShortPulseDPG29 << " " << flagLongPulseDPG29 << " "  
                  << ". Short fibres were cleaned." << std::endl;
            */
            shortFibre -= theShortHitEnergy29;
            theShortHitEnergy29 = 0.;
          }

          // Some energy must be in the long fibres is there is some energy in the short fibres ! 
          if ( theShortHitEnergy29 > shortFibre_Cut && 
               ( theLongHitEnergy29/theShortHitEnergy29 < 2.*longFibre_Fraction || 
             flagShortDPG29 ) ) {
            // Check if the long-fibre hit was not cleaned already (because hot)
            // In this case don't apply the cleaning
            const HcalChannelStatus* theStatus = theHcalChStatus->getValues(theLongDetId29);
            unsigned theStatusValue = theStatus->getValue();
            // The channel is killed
            if ( !theStatusValue ) { 
              //rescaleFactor = 0. ;
              pfrhHFHADCleaned29 = createHcalRecHit( detid, 
                               theShortHitEnergy29, 
                               PFLayer::HF_HAD, 
                               hcalEndcapGeometry,
                               ct.id().rawId() );
              pfrhHFHADCleaned29->setRescale(theShortHit29->time());
              /*
              std::cout << "ieta/iphi = " << ieta29 << " " << iphi 
                << ", Energy em/had/long/short = " 
                << energyemHF << " " << energyhadHF << " "
                << theLongHitEnergy29 << " " << theShortHitEnergy29 << " " 
                << ". Time = " << theShortHit29->time() << " " 
                << ". The status value is " << theStatusValue
                << ". The short and long flags : " 
                << flagShortDPG29 << " " << flagLongDPG29 << " "  
                << flagShortTimeDPG29 << " " << flagLongTimeDPG29 << " "  
                << flagShortPulseDPG29 << " " << flagLongPulseDPG29 << " "  
                << ". Short fibres were cleaned." << std::endl;
              */
              shortFibre -= theShortHitEnergy29;
              theShortHitEnergy29 = 0.;
            }       
          }
          
          // Some energy must be in the short fibres is there is some energy in the long fibres ! 
          if ( theLongHitEnergy29 > longFibre_Cut && 
               ( theShortHitEnergy29/theLongHitEnergy29 < shortFibre_Fraction || 
             flagLongDPG29 ) ) {
            // Check if the long-fibre hit was not cleaned already (because hot)
            // In this case don't apply the cleaning
            const HcalChannelStatus* theStatus = theHcalChStatus->getValues(theShortDetId29);
            unsigned theStatusValue = theStatus->getValue();
            // The channel is killed
            if ( !theStatusValue ) { 
              //rescaleFactor = 0. ;
              pfrhHFEMCleaned29 = createHcalRecHit( detid, 
                                theLongHitEnergy29, 
                                PFLayer::HF_EM, 
                                hcalEndcapGeometry,
                                ct.id().rawId() );
              pfrhHFEMCleaned29->setRescale(theLongHit29->time());
              /* 
              std::cout << "ieta/iphi = " << ieta29 << " " << iphi 
                << ", Energy em/had/long/short = " 
                << energyemHF << " " << energyhadHF << " "
                << theLongHitEnergy29 << " " << theShortHitEnergy29 << " " 
                << ". The status value is " << theStatusValue
                << ". Time = " << theLongHit29->time() << " " 
                << ". The short and long flags : " 
                << flagShortDPG29 << " " << flagLongDPG29 << " "  
                << flagShortTimeDPG29 << " " << flagLongTimeDPG29 << " "  
                << flagShortPulseDPG29 << " " << flagLongPulseDPG29 << " "  
                << ". Long fibres were cleaned." << std::endl;
              */
              longFibre -= theLongHitEnergy29;
              theLongHitEnergy29 = 0.;
            }
          }

          // Check that the energy in tower 29 is smaller than in tower 30
          // First in long fibres
          if ( theLongHitEnergy29 > std::max(theLongHitEnergy,shortFibre_Cut/2) ) { 
            pfrhHFEMCleaned29 = createHcalRecHit( detid, 
                              theLongHitEnergy29, 
                              PFLayer::HF_EM, 
                              hcalEndcapGeometry,
                              ct.id().rawId() );
            pfrhHFEMCleaned29->setRescale(theLongHit29->time());
            /*
            std::cout << "ieta/iphi = " << ieta29 << " " << iphi 
                  << ", Energy L29/S29/L30/S30 = " 
                  << theLongHitEnergy29 << " " << theShortHitEnergy29 << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". Long fibres were cleaned." << std::endl;
            */
            longFibre -= theLongHitEnergy29;
            theLongHitEnergy29 = 0.;
          }
          // Second in short fibres
          if ( theShortHitEnergy29 > std::max(theShortHitEnergy,shortFibre_Cut/2.) ) { 
            pfrhHFHADCleaned29 = createHcalRecHit( detid, 
                               theShortHitEnergy29, 
                               PFLayer::HF_HAD, 
                               hcalEndcapGeometry,
                               ct.id().rawId() );
            pfrhHFHADCleaned29->setRescale(theShortHit29->time());
            /*
            std::cout << "ieta/iphi = " << ieta << " " << iphi 
                  << ", Energy L29/S29/L30/S30 = " 
                  << theLongHitEnergy29 << " " << theShortHitEnergy29 << " "
                  << theLongHitEnergy << " " << theShortHitEnergy << " " 
                  << ". Short fibres were cleaned." << std::endl;
            */
            shortFibre -= theShortHitEnergy29;
            theShortHitEnergy29 = 0.;
          }
        }


        // Determine EM and HAD after cleaning of short and long fibres
        energyhadHF = 2.*shortFibre;
        energyemHF = longFibre - shortFibre;

        // The EM energy might be negative, as it amounts to Long - Short
        // In that case, put the EM "energy" in the HAD energy
        // Just to avoid systematic positive bias due to "Short" high fluctuations
        if ( energyemHF < thresh_HF_ ) { 
          energyhadHF += energyemHF;
          energyemHF = 0.;
        }

        // Apply HCAL calibration factors flor towers close to 29, if requested
        if ( HF_Calib_ && abs(detid.ieta()) <= 32 ) { 
          energyhadHF *= HF_Calib_29;
          energyemHF *= HF_Calib_29;
        }
                
        // Create an EM and a HAD rechit if above threshold.
        if ( energyemHF > thresh_HF_ || energyhadHF > thresh_HF_ ) { 
          pfrhHFEM = createHcalRecHit( detid, 
                           energyemHF, 
                           PFLayer::HF_EM, 
                           hcalEndcapGeometry,
                           ct.id().rawId() );
          pfrhHFHAD = createHcalRecHit( detid, 
                        energyhadHF, 
                        PFLayer::HF_HAD, 
                        hcalEndcapGeometry,
                        ct.id().rawId() );
          pfrhHFEM->setEnergyUp(energyhadHF);
          pfrhHFHAD->setEnergyUp(energyemHF);
        }
        
          }
          break;
        default:
          LogError("PFRecHitProducerHCAL")
        <<"CaloTower constituent: unknown layer : "
        <<detid.subdet()<<endl;
        } 

        if(pfrh) { 
          rechits.push_back( *pfrh );
          delete pfrh;
          idSortedRecHits.insert( make_pair(ct.id().rawId(), 
                        rechits.size()-1 ) ); 
        }
        if(pfrhCleaned) { 
          rechitsCleaned.push_back( *pfrhCleaned );
          delete pfrhCleaned;
        }
        //---ab: 2 rechits for HF:     
        if(pfrhHFEM) { 
          HFEMRecHits->push_back( *pfrhHFEM );
          delete pfrhHFEM;
          idSortedRecHitsHFEM.insert( make_pair(ct.id().rawId(), 
                        HFEMRecHits->size()-1 ) ); 
        }
        if(pfrhHFHAD) { 
          HFHADRecHits->push_back( *pfrhHFHAD );
          delete pfrhHFHAD;
          idSortedRecHitsHFHAD.insert( make_pair(ct.id().rawId(), 
                        HFHADRecHits->size()-1 ) ); 
        }
        //---ab    
        if(pfrhHFEMCleaned) { 
          rechitsCleaned.push_back( *pfrhHFEMCleaned );
          delete pfrhHFEMCleaned;
        }
        if(pfrhHFHADCleaned) { 
          rechitsCleaned.push_back( *pfrhHFHADCleaned );
          delete pfrhHFHADCleaned;
        }
        if(pfrhHFEMCleaned29) { 
          rechitsCleaned.push_back( *pfrhHFEMCleaned29 );
          delete pfrhHFEMCleaned29;
        }
        if(pfrhHFHADCleaned29) { 
          rechitsCleaned.push_back( *pfrhHFHADCleaned29 );
          delete pfrhHFHADCleaned29;
        }
      }
      }
      // do navigation 
      for(unsigned i=0; i<rechits.size(); i++ ) {
    findRecHitNeighboursCT( rechits[i], 
                idSortedRecHits, 
                caloTowerTopology);
      }
      for(unsigned i=0; i<HFEMRecHits->size(); i++ ) {
    findRecHitNeighboursCT( (*HFEMRecHits)[i], 
                idSortedRecHitsHFEM, 
                caloTowerTopology);
      }
      for(unsigned i=0; i<HFHADRecHits->size(); i++ ) {
    findRecHitNeighboursCT( (*HFHADRecHits)[i], 
                idSortedRecHitsHFHAD, 
                caloTowerTopology);
      }
      iEvent.put( HFHADRecHits,"HFHAD" );   
      iEvent.put( HFEMRecHits,"HFEM" ); 
    }   
  }
  else if( !(inputTagHcalRecHitsHBHE_ == InputTag()) ) { 
    // clustering is not done on CaloTowers but on HCAL rechits.
       
  
    // get the hcal topology
    HcalTopology hcalTopology;
    
    // HCAL rechits 
    //    vector<edm::Handle<HBHERecHitCollection> > hcalHandles;  
    edm::Handle<HBHERecHitCollection>  hcalHandle;  

    
    bool found = iEvent.getByLabel(inputTagHcalRecHitsHBHE_, 
                   hcalHandle );

    if(!found) {
      ostringstream err;
      err<<"could not find rechits "<<inputTagHcalRecHitsHBHE_;
      LogError("PFRecHitProducerHCAL")<<err.str()<<endl;
    
      throw cms::Exception( "MissingProduct", err.str());
    }
    else {
      assert( hcalHandle.isValid() );
      
      const edm::Handle<HBHERecHitCollection>& handle = hcalHandle;
      for(unsigned irechit=0; irechit<handle->size(); irechit++) {
    const HBHERecHit& hit = (*handle)[irechit];
    
    double energy = hit.energy();
    
    reco::PFRecHit* pfrh = 0;
    

    const HcalDetId& detid = hit.detid();
    switch( detid.subdet() ) {
    case HcalBarrel:
      {
        if(energy < thresh_Barrel_ ) continue;
        pfrh = createHcalRecHit( detid, 
                     energy, 
                     PFLayer::HCAL_BARREL1, 
                     hcalBarrelGeometry );
      }
      break;
    case HcalEndcap:
      {
        if(energy < thresh_Endcap_ ) continue;
        pfrh = createHcalRecHit( detid, 
                     energy, 
                     PFLayer::HCAL_ENDCAP, 
                     hcalEndcapGeometry );    
      }
      break;
    case HcalForward:
      {
        if(energy < thresh_HF_ ) continue;
        pfrh = createHcalRecHit( detid, 
                     energy, 
                     PFLayer::HF_HAD, 
                     hcalEndcapGeometry );
      }
      break;
    default:
      LogError("PFRecHitProducerHCAL")
        <<"HCAL rechit: unknown layer : "<<detid.subdet()<<endl;
      continue;
    } 

    if(pfrh) { 
      rechits.push_back( *pfrh );
      delete pfrh;
      idSortedRecHits.insert( make_pair(detid.rawId(), 
                        rechits.size()-1 ) ); 
    }
      }
      
      
      // do navigation:
      for(unsigned i=0; i<rechits.size(); i++ ) {
    
    findRecHitNeighbours( rechits[i], idSortedRecHits, 
                  hcalTopology, 
                  *hcalBarrelGeometry, 
                  hcalTopology,
                  *hcalEndcapGeometry);
      } // loop for navigation
    }  // endif hcal rechits were found
  } // endif clustering on rechits in hcal
}






reco::PFRecHit* 
PFRecHitProducerHCAL::createHcalRecHit( const DetId& detid,
                    double energy,
                    PFLayer::Layer layer,
                    const CaloSubdetectorGeometry* geom,
                    unsigned newDetId ) {
  
  const CaloCellGeometry *thisCell = geom->getGeometry(detid);
  if(!thisCell) {
    edm::LogError("PFRecHitProducerHCAL")
      <<"warning detid "<<detid.rawId()<<" not found in layer "
      <<layer<<endl;
    return 0;
  }
  
  const GlobalPoint& position = thisCell->getPosition();
  
  double depth_correction = 0.;
  switch ( layer ) { 
  case PFLayer::HF_EM:
    depth_correction = position.z() > 0. ? EM_Depth_ : -EM_Depth_;
    break;
  case PFLayer::HF_HAD:
    depth_correction = position.z() > 0. ? HAD_Depth_ : -HAD_Depth_;
    break;
  default:
    break;
  }

  unsigned id = detid;
  if(newDetId) id = newDetId;
  reco::PFRecHit *rh = 
    new reco::PFRecHit( id,  layer, energy, 
            position.x(), position.y(), position.z()+depth_correction, 
            0,0,0 );
 
  
  
  
  // set the corners
  const CaloCellGeometry::CornersVec& corners = thisCell->getCorners();

  assert( corners.size() == 8 );

  rh->setNECorner( corners[0].x(), corners[0].y(),  corners[0].z()+depth_correction );
  rh->setSECorner( corners[1].x(), corners[1].y(),  corners[1].z()+depth_correction );
  rh->setSWCorner( corners[2].x(), corners[2].y(),  corners[2].z()+depth_correction );
  rh->setNWCorner( corners[3].x(), corners[3].y(),  corners[3].z()+depth_correction );
 
  return rh;
}




void 
PFRecHitProducerHCAL::findRecHitNeighbours
( reco::PFRecHit& rh, 
  const map<unsigned,unsigned >& sortedHits, 
  const CaloSubdetectorTopology& barrelTopology, 
  const CaloSubdetectorGeometry& barrelGeometry, 
  const CaloSubdetectorTopology& endcapTopology, 
  const CaloSubdetectorGeometry& endcapGeometry ) {
  
  //cout<<"------PFRecHitProducerHcaL:findRecHitNeighbours navigation value "<<navigation_HF_<<endl;
 if(navigation_HF_ == false){
    if( rh.layer() == PFLayer::HF_HAD )
      return;
    if( rh.layer() == PFLayer::HF_EM )
      return;
  } 
  DetId detid( rh.detId() );

  const CaloSubdetectorTopology* topology = 0;
  const CaloSubdetectorGeometry* geometry = 0;
  const CaloSubdetectorGeometry* othergeometry = 0;
  
  switch( rh.layer() ) {
  case PFLayer::ECAL_ENDCAP: 
    topology = &endcapTopology;
    geometry = &endcapGeometry;
    break;
  case PFLayer::ECAL_BARREL: 
    topology = &barrelTopology;
    geometry = &barrelGeometry;
    break;
  case PFLayer::HCAL_ENDCAP:
    topology = &endcapTopology;
    geometry = &endcapGeometry;
    othergeometry = &barrelGeometry;
    break;
  case PFLayer::HCAL_BARREL1:
    topology = &barrelTopology;
    geometry = &barrelGeometry;
    othergeometry = &endcapGeometry;
    break;
  case PFLayer::PS1:
  case PFLayer::PS2:
    topology = &barrelTopology;
    geometry = &barrelGeometry;
    othergeometry = &endcapGeometry;
    break;
  default:
    assert(0);
  }
  
  assert( topology && geometry );

  CaloNavigator<DetId> navigator(detid, topology);

  DetId north = navigator.north();  
  
  DetId northeast(0);
  if( north != DetId(0) ) {
    northeast = navigator.east();  
  }
  navigator.home();


  DetId south = navigator.south();

  

  DetId southwest(0); 
  if( south != DetId(0) ) {
    southwest = navigator.west();
  }
  navigator.home();


  DetId east = navigator.east();
  DetId southeast;
  if( east != DetId(0) ) {
    southeast = navigator.south(); 
  }
  navigator.home();
  DetId west = navigator.west();
  DetId northwest;
  if( west != DetId(0) ) {   
    northwest = navigator.north();  
  }
  navigator.home();
    
  IDH i = sortedHits.find( north.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
  
  i = sortedHits.find( northeast.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
  
  i = sortedHits.find( south.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
    
  i = sortedHits.find( southwest.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( east.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
    
  i = sortedHits.find( southeast.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( west.rawId() );
  if(i != sortedHits.end() ) 
     rh.add4Neighbour( i->second );
   
  i = sortedHits.find( northwest.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    

}


void 
PFRecHitProducerHCAL::findRecHitNeighboursCT
( reco::PFRecHit& rh, 
  const map<unsigned, unsigned >& sortedHits, 
  const CaloSubdetectorTopology& topology ) {
  //cout<<"------PFRecHitProducerHcaL:findRecHitNeighboursCT navigation value "<<navigation_HF_<<endl;
  //  cout<<"----------- rechit print out"<<endl;
  // if(( rh.layer() == PFLayer::HF_HAD )||(rh.layer() == PFLayer::HF_EM)) {  
    
  //    cout<<rh<<endl;
    //  }
  if(navigation_HF_ == false){
    if( rh.layer() == PFLayer::HF_HAD )
      return;
    if( rh.layer() == PFLayer::HF_EM )
      return;
  }
  CaloTowerDetId ctDetId( rh.detId() );
    

  vector<DetId> northids = topology.north(ctDetId);
  vector<DetId> westids = topology.west(ctDetId);
  vector<DetId> southids = topology.south(ctDetId);
  vector<DetId> eastids = topology.east(ctDetId);


  CaloTowerDetId badId;

  // all the following detids will be CaloTowerDetId
  CaloTowerDetId north;
  CaloTowerDetId northwest;
  CaloTowerDetId northwest2;
  CaloTowerDetId west;
  CaloTowerDetId west2;
  CaloTowerDetId southwest;
  CaloTowerDetId southwest2;
  CaloTowerDetId south;
  CaloTowerDetId southeast;
  CaloTowerDetId southeast2;
  CaloTowerDetId east;
  CaloTowerDetId east2;
  CaloTowerDetId northeast;
  CaloTowerDetId northeast2;
  
  // for north and south, there is no ambiguity : 1 or 0 neighbours
  
  switch( northids.size() ) {
  case 0: 
    break;
  case 1: 
    north = northids[0];
    break;
  default:
  stringstream err("PFRecHitProducerHCAL::findRecHitNeighboursCT : incorrect number of neighbours north: "); 
    err<<northids.size();
    throw( err.str() ); 
  }

  switch( southids.size() ) {
  case 0: 
    break;
  case 1: 
    south = southids[0];
    break;
  default:
  stringstream err("PFRecHitProducerHCAL::findRecHitNeighboursCT : incorrect number of neighbours south: "); 
    err<<southids.size();
    throw( err.str() ); 
  }
  
  // for east and west, one must take care 
  // of the pitch change in HCAL endcap.

  switch( eastids.size() ) {
  case 0: 
    break;
  case 1: 
    east = eastids[0];
    northeast = getNorth(east, topology);
    southeast = getSouth(east, topology);
    break;
  case 2:  
    // in this case, 0 is more on the north than 1
    east = eastids[0];
    east2 = eastids[1];
    northeast = getNorth(east, topology );
    southeast = getSouth(east2, topology);    
    northeast2 = getNorth(northeast, topology );
    southeast2 = getSouth(southeast, topology);    
    break;
  default:
  stringstream err("PFRecHitProducerHCAL::findRecHitNeighboursCT : incorrect number of neighbours eastids: "); 
    err<<eastids.size();
    throw( err.str() ); 
  }
  
  
  switch( westids.size() ) {
  case 0: 
    break;
  case 1: 
    west = westids[0];
    northwest = getNorth(west, topology);
    southwest = getSouth(west, topology);
    break;
  case 2:  
    // in this case, 0 is more on the north than 1
    west = westids[0];
    west2 = westids[1];
    northwest = getNorth(west, topology );
    southwest = getSouth(west2, topology );    
    northwest2 = getNorth(northwest, topology );
    southwest2 = getSouth(southwest, topology );    
    break;
  default:
  stringstream err("PFRecHitProducerHCAL::findRecHitNeighboursCT : incorrect number of neighbours westids: "); 
    err<< westids.size();
    throw( err.str() ); 
  }




  // find and set neighbours
    
  IDH i = sortedHits.find( north.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
  
  i = sortedHits.find( northeast.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
  
  i = sortedHits.find( northeast2.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
  
  i = sortedHits.find( south.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
    
  i = sortedHits.find( southwest.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( southwest2.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( east.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
    
  i = sortedHits.find( east2.rawId() );
  if(i != sortedHits.end() ) 
    rh.add4Neighbour( i->second );
    
  i = sortedHits.find( southeast.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( southeast2.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );
    
  i = sortedHits.find( west.rawId() );
  if(i != sortedHits.end() ) 
     rh.add4Neighbour( i->second );
   
  i = sortedHits.find( west2.rawId() );
  if(i != sortedHits.end() ) 
     rh.add4Neighbour( i->second );
   
  i = sortedHits.find( northwest.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );

  i = sortedHits.find( northwest2.rawId() );
  if(i != sortedHits.end() ) 
    rh.add8Neighbour( i->second );

  //  cout<<"----------- rechit print out"<<endl;
  // if(( rh.layer() == PFLayer::HF_HAD )||(rh.layer() == PFLayer::HF_EM)) {  
    
  //   cout<<rh<<endl;
    //  }
}



DetId 
PFRecHitProducerHCAL::getSouth(const DetId& id, 
                   const CaloSubdetectorTopology& topology) {

  DetId south;
  vector<DetId> sids = topology.south(id);
  if(sids.size() == 1)
    south = sids[0];
  
  return south;
} 



DetId 
PFRecHitProducerHCAL::getNorth(const DetId& id, 
                   const CaloSubdetectorTopology& topology) {

  DetId north;
  vector<DetId> nids = topology.north(id);
  if(nids.size() == 1)
    north = nids[0];
  
  return north;
}