/data/refman/pasoursint/CMSSW_4_1_8_patch9/src/FastSimulation/CaloRecHitsProducer/src/HcalRecHitsMaker.cc

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#include "FastSimulation/CaloRecHitsProducer/interface/HcalRecHitsMaker.h"
#include "SimDataFormats/CaloHit/interface/PCaloHitContainer.h"

#include "FWCore/ParameterSet/interface/ParameterSet.h"
#include "DataFormats/Common/interface/Handle.h"
#include "FWCore/Framework/interface/ESHandle.h"
#include "FWCore/Framework/interface/EventSetup.h"
#include "FWCore/Framework/interface/Event.h"
#include "SimDataFormats/CrossingFrame/interface/CrossingFrame.h"        
#include "SimDataFormats/CrossingFrame/interface/MixCollection.h"
#include "Geometry/Records/interface/CaloGeometryRecord.h"
#include "Geometry/CaloGeometry/interface/CaloSubdetectorGeometry.h"
#include "Geometry/CaloGeometry/interface/CaloGeometry.h"
#include "DataFormats/HcalDigi/interface/HBHEDataFrame.h"
#include "CLHEP/GenericFunctions/Erf.hh"
#include "CalibFormats/HcalObjects/interface/HcalTPGRecord.h"
#include "FastSimulation/Utilities/interface/RandomEngine.h"
#include "CalibFormats/HcalObjects/interface/HcalDbService.h"
#include "CondFormats/HcalObjects/interface/HcalGains.h"
#include "CondFormats/HcalObjects/interface/HcalPedestal.h"
#include "SimCalorimetry/HcalSimAlgos/interface/HcalSimParameterMap.h"
#include "CalibCalorimetry/CaloMiscalibTools/interface/MiscalibReaderFromXMLHcal.h"
#include "CalibCalorimetry/CaloMiscalibTools/interface/CaloMiscalibMapHcal.h"
#include "CondFormats/HcalObjects/interface/HcalRespCorrs.h"
#include "CondFormats/DataRecord/interface/HcalRespCorrsRcd.h"

#include "TFile.h"
#include "TGraph.h"
#include "TROOT.h"
#include <fstream>

class RandomEngine;

bool HcalRecHitsMaker::initialized_ = false; 
std::vector<float> HcalRecHitsMaker::peds_;
std::vector<int> HcalRecHitsMaker::fctoadc_;
std::vector<float> HcalRecHitsMaker::sat_;
std::vector<float> HcalRecHitsMaker::gains_;
std::vector<float> HcalRecHitsMaker::noisesigma_;
std::vector<float> HcalRecHitsMaker::TPGFactor_;
std::vector<float> HcalRecHitsMaker::miscalib_;
std::vector<HcalDetId> HcalRecHitsMaker::theDetIds_;
std::vector<int> HcalRecHitsMaker::hbhi_;
std::vector<int> HcalRecHitsMaker::hehi_;
std::vector<int> HcalRecHitsMaker::hohi_;
std::vector<int> HcalRecHitsMaker::hfhi_;
unsigned HcalRecHitsMaker::maxIndex_  = 0 ; 

HcalRecHitsMaker::HcalRecHitsMaker(edm::ParameterSet const & p, int det,
                                   const RandomEngine * myrandom)
  :
  det_(det),
  doDigis_(false),
  noiseFromDb_(false),
  random_(myrandom)
  //,myHcalSimParameterMap_(0)
{
  edm::ParameterSet RecHitsParameters=p.getParameter<edm::ParameterSet>("HCAL");
  noise_ = RecHitsParameters.getParameter<std::vector<double> >("Noise");
  threshold_ = RecHitsParameters.getParameter<std::vector<double> >("Threshold");
  doSaturation_ = RecHitsParameters.getParameter<bool>("EnableSaturation");
    
  refactor_ = RecHitsParameters.getParameter<double> ("Refactor");
  refactor_mean_ = RecHitsParameters.getParameter<double> ("Refactor_mean");
  hcalfileinpath_= RecHitsParameters.getParameter<std::string> ("fileNameHcal");  
  inputCol_=RecHitsParameters.getParameter<edm::InputTag>("MixedSimHits");
  nhbcells_=nhecells_=nhocells_=nhfcells_=0;

  if(det_==4)
    {
      hbhi_.reserve(2600);
      hehi_.reserve(2600);
    }
  else if (det_==5)
    hohi_.reserve(2200);
  else if (det_==6)
    hfhi_.reserve(1800);

  if(threshold_.size()!=noise_.size())
    {
      edm::LogWarning("CaloRecHitsProducer") << " WARNING : HCAL Noise simulation, the number of parameters should be the same for the noise and the thresholds. Disabling the noise simulation " << std::endl;
      noise_.clear();
      noise_.push_back(0.);
    }
  else 
    nnoise_=noise_.size(); 

  //  edm::ParameterSet hcalparam = p2.getParameter<edm::ParameterSet>("hcalSimParam"); 
  //  myHcalSimParameterMap_ = new HcalSimParameterMap(hcalparam);

  // Computes the fraction of HCAL above the threshold
  Genfun::Erf myErf;
  hcalHotFraction_.resize(nnoise_,0.);
  myGaussianTailGenerators_.resize(nnoise_,0);
  if(noise_.size()>0) 
    {
      for(unsigned inoise=0;inoise<nnoise_;++inoise)
        {
          if(noise_[inoise]==0) 
            {
              hcalHotFraction_[inoise]=0.;
              continue;
            }
          else if(noise_[inoise]==-1) {
            noiseFromDb_=true;
            continue;
          }
          else
            {
              hcalHotFraction_.push_back(0.5-0.5*myErf(threshold_[inoise]/noise_[inoise]/sqrt(2.)));
              myGaussianTailGenerators_[inoise]=new GaussianTail(random_,noise_[inoise],threshold_[inoise]);
            }
        }   
    }  
}

HcalRecHitsMaker::~HcalRecHitsMaker()
{
  clean();  
  if(myGaussianTailGenerators_.size()) 
    {
      for(unsigned igt=0; igt<myGaussianTailGenerators_.size();++igt)
        delete myGaussianTailGenerators_[igt];
    }
  myGaussianTailGenerators_.clear();
  theDetIds_.clear();
  hbhi_.clear();
  hehi_.clear();
  hohi_.clear();
  hfhi_.clear();
    
}

void HcalRecHitsMaker::init(const edm::EventSetup &es,bool doDigis,bool doMiscalib)
{
  doDigis_=doDigis;
  doMiscalib_=doMiscalib;
// needed for the noise simulation
  edm::ESHandle<HcalDbService> conditions;
  es.get<HcalDbRecord>().get(conditions);
  const HcalDbService * theDbService=conditions.product();

  // get the correction factors
  edm::ESHandle<HcalRespCorrs> rchandle;
  es.get<HcalRespCorrsRcd>().get(rchandle);
  myRespCorr= rchandle.product();
  

  if(!initialized_) 
    {     
      theDetIds_.resize(9201);
      unsigned ncells=createVectorsOfCells(es);
      edm::LogInfo("CaloRecHitsProducer") << "Total number of cells in HCAL " << ncells << std::endl;
      hcalRecHits_.resize(maxIndex_+1,0.);
      edm::LogInfo("CaloRecHitsProducer") << "Largest HCAL hashedindex" << maxIndex_ << std::endl;

      peds_.resize(9201);
      gains_.resize(9201);
      if(doSaturation_)
        sat_.resize(9201);
      if(noiseFromDb_)
        noisesigma_.resize(9201);
      
      
      
      miscalib_.resize(maxIndex_+1,1.);
      // Read from file ( a la HcalRecHitsRecalib.cc)
      // here read them from xml (particular to HCAL)
      CaloMiscalibMapHcal mapHcal;
      mapHcal.prefillMap();
      

      edm::FileInPath hcalfiletmp("CalibCalorimetry/CaloMiscalibTools/data/"+hcalfileinpath_);      
      std::string hcalfile=hcalfiletmp.fullPath();            
      MiscalibReaderFromXMLHcal hcalreader_(mapHcal);
      if(doMiscalib_ && !hcalfile.empty()) 
        {
          hcalreader_.parseXMLMiscalibFile(hcalfile);
          //      mapHcal.print();
          std::map<uint32_t,float>::const_iterator it=mapHcal.get().begin();
          std::map<uint32_t,float>::const_iterator itend=mapHcal.get().end();
          for(;it!=itend;++it)
            {
              HcalDetId myDetId(it->first);
              float icalconst=it->second;
              miscalib_[myDetId.hashed_index()]=refactor_mean_+(icalconst-refactor_mean_)*refactor_;
            }
        }
      
      
      // Open the histogram for the fC to ADC conversion
      gROOT->cd();
      edm::FileInPath myDataFile("FastSimulation/CaloRecHitsProducer/data/adcvsfc.root");
      TFile * myFile = new TFile(myDataFile.fullPath().c_str(),"READ");
      TGraph * myGraf = (TGraph*)myFile->Get("adcvsfc");
      unsigned size=myGraf->GetN();
      fctoadc_.resize(10000);
      unsigned p_index=0;
      fctoadc_[0]=0;
      int prev_nadc=0;
      int nadc=0;
      for(unsigned ibin=0;ibin<size;++ibin)
        {
          double x,y;
          myGraf->GetPoint(ibin,x,y);
          int index=(int)floor(x);
          if(index<0||index>=10000) continue;
          prev_nadc=nadc;
          nadc=(int)y;
          // Now fills the vector
          for(unsigned ivec=p_index;ivec<(unsigned)index;++ivec)
            {
              fctoadc_[ivec] = prev_nadc;
            }
          p_index = index;
        }
      myFile->Close();
      gROOT->cd();
      edm::FileInPath myTPGFilePath("CalibCalorimetry/HcalTPGAlgos/data/RecHit-TPG-calib.dat");
      TPGFactor_.resize(87,1.2);
      std::ifstream  myTPGFile(myTPGFilePath.fullPath().c_str(),ifstream::in);
      if(myTPGFile)
        {
          float gain;
          myTPGFile >> gain;
          for(unsigned i=0;i<86;++i)
            {
              myTPGFile >> TPGFactor_[i] ;
              //          std::cout << TPGFactor_[i] << std::endl;
            }
        }
      else
        {
          std::cout << " Unable to open CalibCalorimetry/HcalTPGAlgos/data/RecHit-TPG-calib.dat" << std::endl;
          std::cout <<  " Using a constant 1.2 factor " << std::endl;
        }
      //HB
      for(unsigned ic=0;ic<nhbcells_;++ic)
        {
          float gain = theDbService->getGain(theDetIds_[hbhi_[ic]])->getValue(0);
          float mgain=0.;
          for(unsigned ig=0;ig<4;++ig)
            mgain+=theDbService->getGain(theDetIds_[hbhi_[ic]])->getValue(ig);
          if(noiseFromDb_)
            noisesigma_[hbhi_[ic]]=noiseInfCfromDB(theDbService,theDetIds_[hbhi_[ic]])*mgain*0.25;
          //      std::cout << " NOISEHB " << theDetIds_[hbhi_[ic]].ieta() << " " << noisesigma_[hbhi_[ic]] << "  "<< std::endl;
            // 10000 (ADC scale) / 4. (to compute the mean) / 0.92  ADC/fC
  // *1.25 (only ~80% in 1ts Digi, while saturation applied to 4ts RecHit) 
          int ieta=theDetIds_[hbhi_[ic]].ieta();
          float tpgfactor=TPGFactor_[(ieta>0)?ieta+43:-ieta];
          mgain*=2500./0.92*tpgfactor ;// 10000 (ADC scale) / 4. (to compute the mean)
          sat_[hbhi_[ic]]=(doSaturation_)?mgain:99999.;
      
          peds_[hbhi_[ic]]=theDbService->getPedestal(theDetIds_[hbhi_[ic]])->getValue(0);

          gain*=tpgfactor;
          gains_[hbhi_[ic]]=gain;
        }
      //HE

      for(unsigned ic=0;ic<nhecells_;++ic)
        {
          float gain= theDbService->getGain(theDetIds_[hehi_[ic]])->getValue(0);
          int ieta=theDetIds_[hehi_[ic]].ieta();
          float mgain=0.;
          for(unsigned ig=0;ig<4;++ig)
            mgain+=theDbService->getGain(theDetIds_[hehi_[ic]])->getValue(ig);
          if(noiseFromDb_)
            noisesigma_[hehi_[ic]]=noiseInfCfromDB(theDbService,theDetIds_[hehi_[ic]])*mgain*0.25;
      
          //      std::cout << " NOISEHE " << theDetIds_[hehi_[ic]].ieta() << " " << noisesigma_[hehi_[ic]] << "  "<< std::endl;
          float tpgfactor=TPGFactor_[(ieta>0)?ieta+44:-ieta+1];
          mgain*=2500./0.92*tpgfactor;
          sat_[hehi_[ic]]=(doSaturation_)?mgain:99999.;
      
          gain*=tpgfactor;
          peds_[hehi_[ic]]=theDbService->getPedestal(theDetIds_[hehi_[ic]])->getValue(0);
          gains_[hehi_[ic]]=gain;
        }
      //HO

      for(unsigned ic=0;ic<nhocells_;++ic)
        {
          float ped=theDbService->getPedestal(theDetIds_[hohi_[ic]])->getValue(0);
          float gain=theDbService->getGain(theDetIds_[hohi_[ic]])->getValue(0);
          float mgain=0.;
          for(unsigned ig=0;ig<4;++ig)
            mgain+=theDbService->getGain(theDetIds_[hohi_[ic]])->getValue(ig);
          if(noiseFromDb_)
            noisesigma_[hohi_[ic]]=noiseInfCfromDB(theDbService,theDetIds_[hohi_[ic]])*mgain*0.25;
          //      std::cout << " NOISEHO " << theDetIds_[hohi_[ic]].ieta() << " " << noisesigma_[hohi_[ic]] << "  "<< std::endl;
          int ieta=HcalDetId(hohi_[ic]).ieta();
          float tpgfactor=TPGFactor_[(ieta>0)?ieta+43:-ieta];
          mgain*=2500./0.92*tpgfactor;
          sat_[hohi_[ic]]=(doSaturation_)?mgain:99999.;

          gain*=tpgfactor;
          peds_[hohi_[ic]]=ped;
          gains_[hohi_[ic]]=gain;
        }
      //HF

      for(unsigned ic=0;ic<nhfcells_;++ic)
        {
          float ped=theDbService->getPedestal(theDetIds_[hfhi_[ic]])->getValue(0);
          float gain=theDbService->getGain(theDetIds_[hfhi_[ic]])->getValue(0);
          float mgain=0.;
          for(unsigned ig=0;ig<4;++ig)
            mgain+=theDbService->getGain(theDetIds_[hfhi_[ic]])->getValue(ig);
          // additional 1/2 factor for the HF (Salavat)
          if(noiseFromDb_)
            {
              // computation from when the noise was taken 
              noisesigma_[hfhi_[ic]]=noiseInfCfromDB(theDbService,theDetIds_[hfhi_[ic]])*mgain*0.25;
            }
          //      std::cout << " NOISEHF " << theDetIds_[hfhi_[ic]].ieta() << " " << noisesigma_[hfhi_[ic]] << "  "<< std::endl;
      
          mgain*=2500./0.36;
          sat_[hfhi_[ic]]=(doSaturation_)?mgain:99999.;
          int ieta=theDetIds_[hfhi_[ic]].ieta();
          gain*=TPGFactor_[(ieta>0)?ieta+45:-ieta+2];
          peds_[hfhi_[ic]]=ped;
          gains_[hfhi_[ic]]=gain;
        }
      initialized_=true; 
    }
  
  // clear the vector we don't need. It is a bit stupid 
  hcalRecHits_.resize(maxIndex_+1,0.);

}


// Get the PCaloHits from the event. They have to be stored in a map, because when
// the pile-up is added thanks to the Mixing Module, the same cell can be present several times
void HcalRecHitsMaker::loadPCaloHits(const edm::Event & iEvent)
{
  clean();

  edm::Handle<CrossingFrame<PCaloHit> > cf;
  iEvent.getByLabel(inputCol_,cf);
  std::auto_ptr<MixCollection<PCaloHit> > colcalo(new MixCollection<PCaloHit>(cf.product(),std::pair<int,int>(0,0) ));

  MixCollection<PCaloHit>::iterator it=colcalo->begin();;
  MixCollection<PCaloHit>::iterator itend=colcalo->end();
  unsigned counter=0;
  for(;it!=itend;++it)
    {
      HcalDetId detid(it->id());
      int hashedindex=detid.hashed_index();
      switch(detid.subdet())
        {
        case HcalBarrel: 
          {
            if(det_==4)
              Fill(hashedindex,it->energy(),firedCells_,noise_[0]);
          }
          break;
        case HcalEndcap: 
          {       
            if(det_==4)
              Fill(hashedindex,it->energy(),firedCells_,noise_[1]);
          }
          break;
        case HcalOuter: 
          {
            if(det_==5)
              Fill(hashedindex,it->energy(),firedCells_,noise_[0]);
          }
          break;                     
        case HcalForward: 
          {
            if(det_==6)
              Fill(hashedindex,it->energy(),firedCells_,noise_[0]);
          }
          break;
        default:
          edm::LogWarning("CaloRecHitsProducer") << "RecHit not registered\n";
          ;
        }
      ++counter;
    }
}

// Fills the collections. 
void HcalRecHitsMaker::loadHcalRecHits(edm::Event &iEvent,HBHERecHitCollection& hbheHits, HBHEDigiCollection& hbheDigis)
{
  loadPCaloHits(iEvent);
  noisify();
  hbheHits.reserve(firedCells_.size());
  if(doDigis_)
    {
      hbheDigis.reserve(firedCells_.size());
    }
  static HcalQIESample zeroSample(0,0,0,0);
  unsigned nhits=firedCells_.size();
  // HB and HE

  for(unsigned ihit=0;ihit<nhits;++ihit)
    {
      unsigned cellhashedindex=firedCells_[ihit];
      const HcalDetId& detid  = theDetIds_[cellhashedindex];
      unsigned subdet=(detid.subdet()==HcalBarrel) ? 0: 1;      

      // Check if it is above the threshold
      if(hcalRecHits_[cellhashedindex]<threshold_[subdet]) continue; 
      float energy=hcalRecHits_[cellhashedindex];
      // apply RespCorr only to the RecHit
      energy *= myRespCorr->getValues(theDetIds_[cellhashedindex])->getValue();
      // poor man saturation
      if(energy>sat_[cellhashedindex]) 
        {
          //      std::cout << " Saturation " << energy << " " << sat_[cellhashedindex] << " HB " << std::endl;
          energy=sat_[cellhashedindex];
        }
      

      hbheHits.push_back(HBHERecHit(detid,energy,0.));      
      if(doDigis_)
        {
          HBHEDataFrame myDataFrame(detid);
          myDataFrame.setSize(2);
          double nfc=hcalRecHits_[cellhashedindex]/gains_[cellhashedindex]+peds_[cellhashedindex];
          int nadc=fCtoAdc(nfc);
          HcalQIESample qie(nadc, 0, 0, 0) ;
          myDataFrame.setSample(0,qie);
          myDataFrame.setSample(1,zeroSample);
          hbheDigis.push_back(myDataFrame);
        }
    }
}


// Fills the collections. 
void HcalRecHitsMaker::loadHcalRecHits(edm::Event &iEvent, HORecHitCollection &hoHits, HODigiCollection & hoDigis)
{
  loadPCaloHits(iEvent);
  noisify();
  hoHits.reserve(firedCells_.size());
  if(doDigis_)
    {
      hoDigis.reserve(firedCells_.size());
    }
  static HcalQIESample zeroSample(0,0,0,0);

  // HO
  unsigned nhits=firedCells_.size();
  for(unsigned ihit=0;ihit<nhits;++ihit)
    {

      unsigned cellhashedindex=firedCells_[ihit];
      // Check if it is above the threshold
      if(hcalRecHits_[cellhashedindex]<threshold_[0]) continue; 

      float energy=hcalRecHits_[cellhashedindex];
      // apply RespCorr
      energy *= myRespCorr->getValues(theDetIds_[cellhashedindex])->getValue();

      // poor man saturation
      if(energy>sat_[cellhashedindex]) energy=sat_[cellhashedindex];

      const HcalDetId&  detid=theDetIds_[cellhashedindex];

      hoHits.push_back(HORecHit(detid,energy,0));
    }
}

// Fills the collections. 
void HcalRecHitsMaker::loadHcalRecHits(edm::Event &iEvent,HFRecHitCollection &hfHits, HFDigiCollection& hfDigis)
{
  loadPCaloHits(iEvent);
  noisify();
  hfHits.reserve(firedCells_.size());
  if(doDigis_)
    {
      hfDigis.reserve(firedCells_.size());
    }
  static HcalQIESample zeroSample(0,0,0,0);

  unsigned nhits=firedCells_.size();
  for(unsigned ihit=0;ihit<nhits;++ihit)
    {
      unsigned cellhashedindex=firedCells_[ihit];
      // Check if it is above the threshold
      if(hcalRecHits_[cellhashedindex]<threshold_[0]) continue; 

      float energy=hcalRecHits_[cellhashedindex];

      // apply RespCorr
      energy *= myRespCorr->getValues(theDetIds_[cellhashedindex])->getValue();

      // poor man saturation
      if(energy>sat_[cellhashedindex]) energy=sat_[cellhashedindex];

      const HcalDetId & detid=theDetIds_[cellhashedindex];
      hfHits.push_back(HFRecHit(detid,energy,0.));      
      if(doDigis_)
        {
          HFDataFrame myDataFrame(detid);
          myDataFrame.setSize(1);

          double nfc= hcalRecHits_[cellhashedindex]/gains_[cellhashedindex]+peds_[cellhashedindex];
          int nadc=fCtoAdc(nfc/2.6);
          HcalQIESample qie(nadc, 0, 0, 0) ;
          myDataFrame.setSample(0,qie);
          hfDigis.push_back(myDataFrame);
        }
    }
}


// For a fast injection of the noise: the list of cell ids is stored
unsigned HcalRecHitsMaker::createVectorsOfCells(const edm::EventSetup &es)
{
    edm::ESHandle<CaloGeometry> pG;
    es.get<CaloGeometryRecord>().get(pG);     
    nhbcells_ = createVectorOfSubdetectorCells(*pG, HcalBarrel,  hbhi_);    
    nhecells_ = createVectorOfSubdetectorCells(*pG, HcalEndcap,  hehi_);
    nhocells_ = createVectorOfSubdetectorCells(*pG, HcalOuter,   hohi_);
    nhfcells_ = createVectorOfSubdetectorCells(*pG, HcalForward, hfhi_);    

    return nhbcells_+nhecells_+nhocells_+nhfcells_;
}

// list of the cellids for a given subdetector
unsigned HcalRecHitsMaker::createVectorOfSubdetectorCells(const CaloGeometry& cg,int subdetn,std::vector<int>& cellsvec ) 
{

  const CaloSubdetectorGeometry* geom=cg.getSubdetectorGeometry(DetId::Hcal,subdetn);  
  const std::vector<DetId>& ids=geom->getValidDetIds(DetId::Hcal,subdetn);  

  for (std::vector<DetId>::const_iterator i=ids.begin(); i!=ids.end(); i++) 
    {
      HcalDetId myDetId(*i);
      //      std::cout << myDetId << myHcalSimParameterMap_->simParameters(myDetId).simHitToPhotoelectrons() << std::endl;;
      //      std::cout << " hi " << hi << " " theDetIds_.size() << std::endl;
      unsigned hi=myDetId.hashed_index();
      theDetIds_[hi]=myDetId;
      //      std::cout << myDetId << " " << hi <<  std::endl;
      cellsvec.push_back(hi);      

      if(hi>maxIndex_)
        maxIndex_=hi;
    }
  return cellsvec.size();
}

// Takes a hit (from a PSimHit) and fills a map 
void HcalRecHitsMaker::Fill(int id, float energy, std::vector<int>& theHits,float noise)
{
  if(doMiscalib_) 
    energy*=miscalib_[id];

  if(noiseFromDb_)
    noise=noisesigma_[id];

  // Check if the RecHit exists
  if(hcalRecHits_[id]>0.)
    hcalRecHits_[id]+=energy;
  else
    {
      // the noise is injected only the first time
      hcalRecHits_[id]=energy + random_->gaussShoot(0.,noise);
      theHits.push_back(id);
    }
}

void HcalRecHitsMaker::noisify()
{
  unsigned total=0;
  switch(det_)
    {
    case 4:
      {
        // do the HB
        if(noise_[0] != 0.) {
          total+=noisifySubdet(hcalRecHits_,firedCells_,hbhi_,nhbcells_,hcalHotFraction_[0],myGaussianTailGenerators_[0],noise_[0],threshold_[0]);
        }
        // do the HE
        if(noise_[1] != 0.) {    
          total+=noisifySubdet(hcalRecHits_,firedCells_,hehi_,nhecells_,hcalHotFraction_[1],myGaussianTailGenerators_[1],noise_[1],threshold_[1]);
        }
      }
      break;
    case 5:
      {
        // do the HO
        if(noise_[0] != 0.) {
          total+=noisifySubdet(hcalRecHits_,firedCells_,hohi_,nhocells_,hcalHotFraction_[0],myGaussianTailGenerators_[0],noise_[0],threshold_[0]);
        }
      }
      break;
    case 6:
      {
        // do the HF
        if(noise_[0] != 0.) {
          total+=noisifySubdet(hcalRecHits_,firedCells_,hfhi_,nhfcells_,hcalHotFraction_[0],myGaussianTailGenerators_[0],noise_[0],threshold_[0]);
        }
      }
      break;
    default:
      break;
    }
  edm::LogInfo("CaloRecHitsProducer") << "CaloRecHitsProducer : added noise in "<<  total << " HCAL cells "  << std::endl;
}

unsigned HcalRecHitsMaker::noisifySubdet(std::vector<float>& theMap, std::vector<int>& theHits, const std::vector<int>& thecells, unsigned ncells, double hcalHotFraction,const GaussianTail *myGT,double sigma,double threshold)
{
 // If the fraction of "hot " is small, use an optimized method to inject noise only in noisy cells. The 30% has not been tuned
  if(!noiseFromDb_ && hcalHotFraction==0.) return 0;
  if(hcalHotFraction<0.3 && !noiseFromDb_)
    {
      double mean = (double)(ncells-theHits.size())*hcalHotFraction;
      unsigned nhcal = random_->poissonShoot(mean);
  
      unsigned ncell=0;
      unsigned cellindex=0;
      uint32_t cellhashedindex=0;
      
      while(ncell < nhcal)
        {
          cellindex = (unsigned)(random_->flatShoot()*ncells);
          cellhashedindex = thecells[cellindex];
          if(hcalRecHits_[cellhashedindex]==0.) // new cell
            {
              hcalRecHits_[cellhashedindex]=myGT->shoot();
              theHits.push_back(cellhashedindex);
              ++ncell;
            }
        }
      return ncell;
    }
  else // otherwise, inject noise everywhere
    {
      uint32_t cellhashedindex=0;
      unsigned nhcal=thecells.size();


      for(unsigned ncell=0;ncell<nhcal;++ncell)
        {
          cellhashedindex = thecells[ncell];
          if(hcalRecHits_[cellhashedindex]==0.) // new cell
            {
              
              sigma=noisesigma_[cellhashedindex];

              double noise =random_->gaussShoot(0.,sigma);
              if(noise>threshold)
                {
                  hcalRecHits_[cellhashedindex]=noise;              
                  theHits.push_back(cellhashedindex);
                }
            }
        }
      return nhcal;
    }
  return 0;
}

void HcalRecHitsMaker::clean()
{
  cleanSubDet(hcalRecHits_,firedCells_);
}

void HcalRecHitsMaker::cleanSubDet(std::vector<float>& hits,std::vector<int>& cells)
{
  unsigned size=cells.size();
  // Reset the energies
  for(unsigned ic=0;ic<size;++ic)
    {
      hits[cells[ic]] = 0.;
    }
  // Clear the list of fired cells 
  cells.clear();
}

// fC to ADC conversion
int HcalRecHitsMaker::fCtoAdc(double fc) const
{
  if(fc<0.) return 0;
  if(fc>9985.) return 127;
  return fctoadc_[(unsigned)floor(fc)];
}

double HcalRecHitsMaker::noiseInfCfromDB(const HcalDbService * conditions,const HcalDetId & detId)
{
  // method from Salavat
  // fetch pedestal widths (noise sigmas for all 4 CapID)
  const HcalPedestalWidth* pedWidth =
    conditions-> getPedestalWidth(detId); 
  double ssqq_1 = pedWidth->getSigma(0,0);
  double ssqq_2 = pedWidth->getSigma(1,1);
  double ssqq_3 = pedWidth->getSigma(2,2);
  double ssqq_4 = pedWidth->getSigma(3,3);

  // correction factors (hb,he,ho,hf)
  static float corrfac[4]={1.39,1.32,1.53,3.76};

  int sub   = detId.subdet();
  
  // effective RecHits (for this particular detId) noise calculation :
  
  double sig_sq_mean =  0.25 * ( ssqq_1 + ssqq_2 + ssqq_3 + ssqq_4);
  
  // f - external parameter (currently set to 0.5 in the FullSim) !!!
  double f=0.5;

  double term  = sqrt (1. + sqrt(1. - 2.*f*f));
  double alpha = sqrt (0.5) * term;
  double beta  = sqrt (0.5) * f / term;

  //  double RMS1   = sqrt(sig_sq_mean) * sqrt (2.*beta*beta + alpha*alpha) ;
  double RMS4   = sqrt(sig_sq_mean) * sqrt (2.*beta*beta + 2.*(alpha-beta)*(alpha-beta) + 2.*(alpha-2.*beta)*(alpha-2.*beta)) ;

  double noise_rms_fC;

  //  if(sub == 4)  noise_rms_fC = RMS1;
  //  else          noise_rms_fC = RMS4;
  noise_rms_fC = RMS4;

  noise_rms_fC *= corrfac[sub-1];

  // to convert from above fC to GeV - multiply by gain (GeV/fC)        
  //  const HcalGain*  gain = conditions->getGain(detId); 
  //  double noise_rms_GeV = noise_rms_fC * gain->getValue(0); // Noise RMS (GeV) for detId channel
  return noise_rms_fC;
}