#include <PFClusterWidthAlgo.h>

Public Member Functions
	PFClusterWidthAlgo (const std::vector< const reco::PFCluster * > &pfclust, const EBRecHitCollection ebRecHits=0, const EERecHitCollection eeRecHits=0)

double	pflowEtaWidth () const

double	pflowPhiWidth () const

double	pflowSigmaEtaEta () const

	~PFClusterWidthAlgo ()

Private Attributes
double	etaWidth_

double	phiWidth_

double	sigmaEtaEta_

Detailed Description

Definition at line 6 of file PFClusterWidthAlgo.h.

Constructor & Destructor Documentation

PFClusterWidthAlgo::PFClusterWidthAlgo	(	const std::vector< const reco::PFCluster * > &	pfclust,
		const EBRecHitCollection *	ebRecHits = `0`,
		const EERecHitCollection *	eeRecHits = `0`
	)

Definition at line 13 of file PFClusterWidthAlgo.cc.

References cuy::denominator, dPhi(), alignCSCRings::e, DetId::Ecal, EcalBarrel, EcalEndcap, edm::SortedCollection< T, SORT >::end(), edm::SortedCollection< T, SORT >::find(), getHLTprescales::index, edm::Ref< C, T, F >::isAvailable(), Pi, mathSSE::sqrt(), and TwoPi.

                                                             {
 
 
   double numeratorEtaWidth = 0.;
   double numeratorPhiWidth = 0.;
   double sclusterE = 0.;
   double posX = 0.;
   double posY = 0.;
   double posZ = 0.;
   sigmaEtaEta_ = 0.;
 
   unsigned int nclust= pfclust.size();
   if(nclust == 0 ) {
     etaWidth_ = 0.;
     phiWidth_ = 0.;
     sigmaEtaEta_ = 0.;
   }
   else {
 
     for(unsigned int icl=0;icl<nclust;++icl) {
       double e = pfclust[icl]->energy();
       sclusterE += e;
       posX += e * pfclust[icl]->position().X();
       posY += e * pfclust[icl]->position().Y();
       posZ += e * pfclust[icl]->position().Z();   
     }
     
     posX /=sclusterE;
     posY /=sclusterE;
     posZ /=sclusterE;
     
     double denominator = sclusterE;
     
     math::XYZPoint pflowSCPos(posX,posY,posZ);
     
     double scEta    = pflowSCPos.eta();
     double scPhi    = pflowSCPos.phi();
     
     double SeedClusEnergy = -1.;
     unsigned int SeedDetID = 0;
     double SeedEta = -1.;
 
     for(unsigned int icl=0; icl<nclust; ++icl) {
       const std::vector< reco::PFRecHitFraction >& PFRecHits =  pfclust[icl]->recHitFractions();
       
       
       for ( std::vector< reco::PFRecHitFraction >::const_iterator it = PFRecHits.begin(); 
         it != PFRecHits.end(); ++it) {
     const PFRecHitRef& RefPFRecHit = it->recHitRef(); 
     double energyHit=0;
     // if the PFRecHit is not available, try to get it from the collections
     //  if(!RefPFRecHit.isAvailable() && ebRecHits && eeRecHits )
     if(ebRecHits && eeRecHits )
       {
         //      std::cout << " Recomputing " << std::endl;
         unsigned index=it-PFRecHits.begin();
         DetId id=pfclust[icl]->hitsAndFractions()[index].first;
         // look for the hit; do not forget to multiply by the fraction
         if(id.det()==DetId::Ecal && id.subdetId()==EcalBarrel)
           {
         EBRecHitCollection::const_iterator itcheck=ebRecHits->find(id);
         if(itcheck!=ebRecHits->end())
           energyHit= itcheck->energy();
         // The cluster shapes do not take into account the RecHit fraction !        
         // * pfclust[icl]->hitsAndFractions()[index].second;
           }
         if(id.det()==DetId::Ecal && id.subdetId()==EcalEndcap)
           {
         EERecHitCollection::const_iterator itcheck=eeRecHits->find(id);
         if(itcheck!=eeRecHits->end())
           energyHit= itcheck->energy();
         // The cluster shapes do not take into account the RecHit fraction !        
         //               * pfclust[icl]->hitsAndFractions()[index].second;
           }
       }
     else
       energyHit = RefPFRecHit->energy();
 
     //only for the first cluster (from GSF) find the seed
     if(icl==0) {
       if (energyHit > SeedClusEnergy) {
         SeedClusEnergy = energyHit;
         SeedEta = RefPFRecHit->position().eta();
         SeedDetID = RefPFRecHit->detId();
       }
     }
 
 
     double dPhi = RefPFRecHit->position().phi() - scPhi;
     if (dPhi > + TMath::Pi()) { dPhi = TMath::TwoPi() - dPhi; }
     if (dPhi < - TMath::Pi()) { dPhi = TMath::TwoPi() + dPhi; }
     double dEta = RefPFRecHit->position().eta() - scEta;
     if ( energyHit > 0 ) {
       numeratorEtaWidth += energyHit * dEta * dEta;
       numeratorPhiWidth += energyHit * dPhi * dPhi;
     }
       }
     } // end for ncluster
 
     //for the first cluster (from GSF) computed sigmaEtaEta
     const std::vector< reco::PFRecHitFraction >& PFRecHits =  pfclust[0]->recHitFractions();
     for ( std::vector< reco::PFRecHitFraction >::const_iterator it = PFRecHits.begin(); 
       it != PFRecHits.end(); ++it) {
       const PFRecHitRef& RefPFRecHit = it->recHitRef(); 
       if(!RefPFRecHit.isAvailable()) 
     return;
       double energyHit = RefPFRecHit->energy();
       if (RefPFRecHit->detId() != SeedDetID) {
     float diffEta =  RefPFRecHit->position().eta() - SeedEta;
     sigmaEtaEta_ += (diffEta*diffEta) * (energyHit/SeedClusEnergy);
       }
     }
     if (sigmaEtaEta_ == 0.) sigmaEtaEta_ = 0.00000001;
 
     etaWidth_ = sqrt(numeratorEtaWidth / denominator);
     phiWidth_ = sqrt(numeratorPhiWidth / denominator);
     
 
   } // endif ncluster > 0
 }