#include <TrackGenAssociatorByChi2Impl.h>

Inheritance diagram for TrackGenAssociatorByChi2Impl:

Public Types
typedef std::map< double, SimTrack >	Chi2SimMap

typedef std::pair< reco::Track, Chi2SimMap >	RecoToSimPair

typedef std::vector< RecoToSimPair >	RecoToSimPairAssociation

Public Member Functions
reco::GenToRecoCollection	associateGenToReco (const edm::RefToBaseVector< reco::Track > &, const edm::RefVector< reco::GenParticleCollection > &) const override
	Association Sim To Reco with Collections (Gen Particle version) More...

reco::GenToRecoCollection	associateGenToReco (const edm::Handle< edm::View< reco::Track > > &tCH, const edm::Handle< reco::GenParticleCollection > &tPCH) const override
	compare reco to sim the handle of reco::Track and GenParticle collections More...

reco::RecoToGenCollection	associateRecoToGen (const edm::RefToBaseVector< reco::Track > &, const edm::RefVector< reco::GenParticleCollection > &) const override
	Association Sim To Reco with Collections (Gen Particle version) More...

reco::RecoToGenCollection	associateRecoToGen (const edm::Handle< edm::View< reco::Track > > &tCH, const edm::Handle< reco::GenParticleCollection > &tPCH) const override
	compare reco to sim the handle of reco::Track and GenParticle collections More...

	TrackGenAssociatorByChi2Impl (const MagneticField &mF, const reco::BeamSpot &bs, double chi2Cut, bool onlyDiag)
	Constructor with PSet. More...

Public Member Functions inherited from reco::TrackToGenParticleAssociatorBaseImpl
	TrackToGenParticleAssociatorBaseImpl ()
	Constructor. More...

virtual	~TrackToGenParticleAssociatorBaseImpl ()

Private Member Functions
double	associateRecoToSim (reco::TrackCollection::const_iterator, TrackingParticleCollection::const_iterator, const reco::BeamSpot &) const
	compare reco::TrackCollection and TrackingParticleCollection iterators: returns the chi2 More...

double	getChi2 (const reco::TrackBase::ParameterVector &rParameters, const reco::TrackBase::CovarianceMatrix &recoTrackCovMatrix, const Basic3DVector< double > &momAtVtx, const Basic3DVector< double > &vert, int charge, const reco::BeamSpot &) const
	basic method where chi2 is computed More...

Private Attributes
double	chi2cut

bool	onlyDiagonal

const reco::BeamSpot *	theBeamSpot

const MagneticField *	theMF

Detailed Description

Class that performs the association of reco::Tracks and TrackingParticles evaluating the chi2 of reco tracks parameters and sim tracks parameters. The cut can be tuned from the config file: see data/TrackGenAssociatorByChi2.cfi. Note that the Association Map is filled with -ch2 and not chi2 because it is ordered using std::greater: the track with the lowest association chi2 will be the first in the output map.It is possible to use only diagonal terms (associator by pulls) seeting onlyDiagonal = true in the PSet

Author: cerati, magni

Definition at line 36 of file TrackGenAssociatorByChi2Impl.h.

Member Typedef Documentation

typedef std::map<double, SimTrack> TrackGenAssociatorByChi2Impl::Chi2SimMap

Definition at line 39 of file TrackGenAssociatorByChi2Impl.h.

typedef std::pair< reco::Track, Chi2SimMap> TrackGenAssociatorByChi2Impl::RecoToSimPair

Definition at line 40 of file TrackGenAssociatorByChi2Impl.h.

typedef std::vector< RecoToSimPair > TrackGenAssociatorByChi2Impl::RecoToSimPairAssociation

Definition at line 41 of file TrackGenAssociatorByChi2Impl.h.

Constructor & Destructor Documentation

TrackGenAssociatorByChi2Impl::TrackGenAssociatorByChi2Impl	(	const MagneticField &	mF,
		const reco::BeamSpot &	bs,
		double	chi2Cut,
		bool	onlyDiag
	)

inline

Constructor with PSet.

Constructor with magnetic field, double, bool and InputTag

Definition at line 46 of file TrackGenAssociatorByChi2Impl.h.

                                                              :
   theMF(&mF),
     theBeamSpot(&bs),
     chi2cut(chi2Cut),
     onlyDiagonal(onlyDiag)
     {
     }

Member Function Documentation

GenToRecoCollection TrackGenAssociatorByChi2Impl::associateGenToReco	(	const edm::RefToBaseVector< reco::Track > &	tC,
		const edm::RefVector< reco::GenParticleCollection > &	tPCH
	)		const

overridevirtual

Association Sim To Reco with Collections (Gen Particle version)

Implements reco::TrackToGenParticleAssociatorBaseImpl.

Definition at line 79 of file TrackGenAssociatorByChi2Impl.cc.

References edm::RefToBaseVector< T >::begin(), edm::RefVector< C, T, F >::begin(), ALCARECOTkAlJpsiMuMu_cff::charge, vertices_cff::chi2, trackAssociatorByChi2_cfi::chi2cut, edm::RefToBaseVector< T >::end(), edm::RefVector< C, T, F >::end(), mps_fire::i, edm::AssociationMap< Tag >::insert(), LogDebug, trackAssociatorByChi2_cfi::onlyDiagonal, edm::AssociationMap< Tag >::post_insert(), and mathSSE::sqrt().

                                                                                                                             {
   reco::BeamSpot const& bs = *theBeamSpot;      
 
   GenToRecoCollection  outputCollection;
 
   int tpindex =0;
   for (auto tp=tPCH.begin(); tp!=tPCH.end(); tp++, ++tpindex){
     
     //skip tps with a very small pt
     //if (sqrt((*tp)->momentum().perp2())<0.5) continue;
     int charge = (*tp)->charge();
     if (charge==0) continue;
     
     LogDebug("TrackAssociator") << "=========LOOKING FOR ASSOCIATION===========" << "\n"
                 << "TrackingParticle #"<<tpindex<<" with pt=" << sqrt((*tp)->momentum().perp2()) << "\n"
                 << "===========================================" << "\n";
     
     Basic3DVector<double> momAtVtx((*tp)->momentum().x(),(*tp)->momentum().y(),(*tp)->momentum().z());
     Basic3DVector<double> vert((*tp)->vertex().x(),(*tp)->vertex().y(),(*tp)->vertex().z());
       
     int tindex=0;
     for (RefToBaseVector<reco::Track>::const_iterator rt=tC.begin(); rt!=tC.end(); rt++, tindex++){
       
       TrackBase::ParameterVector rParameters = (*rt)->parameters();      
       TrackBase::CovarianceMatrix recoTrackCovMatrix = (*rt)->covariance();
       if (onlyDiagonal) {
     for (unsigned int i=0;i<5;i++){
       for (unsigned int j=0;j<5;j++){
         if (i!=j) recoTrackCovMatrix(i,j)=0;
       }
     }
       }
       recoTrackCovMatrix.Invert();
       
       double chi2 = getChi2(rParameters,recoTrackCovMatrix,momAtVtx,vert,charge,bs);
       
       if (chi2<chi2cut) {
     outputCollection.insert(*tp,
                 std::make_pair(tC[tindex],
                            -chi2));//-chi2 because the Association Map is ordered using std::greater
       }
     }
   }
   outputCollection.post_insert();
   return outputCollection;
 }

reco::GenToRecoCollection TrackGenAssociatorByChi2Impl::associateGenToReco	(	const edm::Handle< edm::View< reco::Track > > &	tCH,
		const edm::Handle< reco::GenParticleCollection > &	tPCH
	)		const

inlineoverridevirtual

compare reco to sim the handle of reco::Track and GenParticle collections

Implements reco::TrackToGenParticleAssociatorBaseImpl.

Definition at line 79 of file TrackGenAssociatorByChi2Impl.h.

References ALCARECOTkAlJpsiMuMu_cff::charge, edm::HandleBase::id(), edm::RefToBaseVector< T >::push_back(), and edm::RefVector< C, T, F >::push_back().

                                                                                                 {
     edm::RefToBaseVector<reco::Track> tc(tCH);
     for (unsigned int j=0; j<tCH->size();j++)
       tc.push_back(edm::RefToBase<reco::Track>(tCH,j));
 
     edm::RefVector<reco::GenParticleCollection> tpc(tPCH.id());
     for (unsigned int j=0; j<tPCH->size();j++)
       tpc.push_back(edm::Ref<reco::GenParticleCollection>(tPCH,j));
 
     return associateGenToReco(tc,tpc);
   }  

RecoToGenCollection TrackGenAssociatorByChi2Impl::associateRecoToGen	(	const edm::RefToBaseVector< reco::Track > &	tC,
		const edm::RefVector< reco::GenParticleCollection > &	tPCH
	)		const

overridevirtual

Association Sim To Reco with Collections (Gen Particle version)

Implements reco::TrackToGenParticleAssociatorBaseImpl.

Definition at line 21 of file TrackGenAssociatorByChi2Impl.cc.

References edm::RefToBaseVector< T >::begin(), ALCARECOTkAlJpsiMuMu_cff::charge, vertices_cff::chi2, trackAssociatorByChi2_cfi::chi2cut, edm::RefToBaseVector< T >::end(), mps_fire::i, edm::AssociationMap< Tag >::insert(), LogDebug, trackAssociatorByChi2_cfi::onlyDiagonal, edm::AssociationMap< Tag >::post_insert(), and edm::RefVector< C, T, F >::size().

                                                                                                                             {
   reco::BeamSpot const& bs = *theBeamSpot;
 
   RecoToGenCollection  outputCollection;
 
   //dereference the edm::Refs only once
   std::vector<GenParticle const*> tPC;
   tPC.reserve(tPCH.size());
   for(auto const& ref: tPCH) {
     tPC.push_back(&(*ref));
   }
 
   int tindex=0;
   for (RefToBaseVector<reco::Track>::const_iterator rt=tC.begin(); rt!=tC.end(); rt++, tindex++){
 
     LogDebug("TrackAssociator") << "=========LOOKING FOR ASSOCIATION===========" << "\n"
                 << "rec::Track #"<<tindex<<" with pt=" << (*rt)->pt() <<  "\n"
                 << "===========================================" << "\n";
  
     TrackBase::ParameterVector rParameters = (*rt)->parameters();
 
     TrackBase::CovarianceMatrix recoTrackCovMatrix = (*rt)->covariance();
     if (onlyDiagonal){
       for (unsigned int i=0;i<5;i++){
     for (unsigned int j=0;j<5;j++){
       if (i!=j) recoTrackCovMatrix(i,j)=0;
     }
       }
     } 
 
     recoTrackCovMatrix.Invert();
 
     int tpindex =0;
     for (auto tp=tPC.begin(); tp!=tPC.end(); tp++, ++tpindex){
     
       //skip tps with a very small pt
       //if (sqrt((*tp)->momentum().perp2())<0.5) continue;
       int charge = (*tp)->charge();
       if (charge==0) continue;
       Basic3DVector<double> momAtVtx((*tp)->momentum().x(),(*tp)->momentum().y(),(*tp)->momentum().z());
       Basic3DVector<double> vert=(Basic3DVector<double>) (*tp)->vertex();
 
       double chi2 = getChi2(rParameters,recoTrackCovMatrix,momAtVtx,vert,charge,bs);
       
       if (chi2<chi2cut) {
         //NOTE: tPC and tPCH use the same index for the same object
     outputCollection.insert(tC[tindex], 
                 std::make_pair(tPCH[tpindex],
                            -chi2));//-chi2 because the Association Map is ordered using std::greater
       }
     }
   }
   outputCollection.post_insert();
   return outputCollection;
 }

reco::RecoToGenCollection TrackGenAssociatorByChi2Impl::associateRecoToGen	(	const edm::Handle< edm::View< reco::Track > > &	tCH,
		const edm::Handle< reco::GenParticleCollection > &	tPCH
	)		const

inlineoverridevirtual

compare reco to sim the handle of reco::Track and GenParticle collections

Implements reco::TrackToGenParticleAssociatorBaseImpl.

Definition at line 65 of file TrackGenAssociatorByChi2Impl.h.

References edm::HandleBase::id(), edm::RefToBaseVector< T >::push_back(), and edm::RefVector< C, T, F >::push_back().

                                                                                                 { 
     edm::RefToBaseVector<reco::Track> tc(tCH);
     for (unsigned int j=0; j<tCH->size();j++)
       tc.push_back(edm::RefToBase<reco::Track>(tCH,j));
 
     edm::RefVector<reco::GenParticleCollection> tpc(tPCH.id());
     for (unsigned int j=0; j<tPCH->size();j++)
       tpc.push_back(edm::Ref<reco::GenParticleCollection>(tPCH,j));
 
     return associateRecoToGen(tc,tpc);
   }

double TrackGenAssociatorByChi2Impl::associateRecoToSim	(	reco::TrackCollection::const_iterator	,
		TrackingParticleCollection::const_iterator	,
		const reco::BeamSpot &
	)		const

private

compare reco::TrackCollection and TrackingParticleCollection iterators: returns the chi2

double TrackGenAssociatorByChi2Impl::getChi2	(	const reco::TrackBase::ParameterVector &	rParameters,
		const reco::TrackBase::CovarianceMatrix &	recoTrackCovMatrix,
		const Basic3DVector< double > &	momAtVtx,
		const Basic3DVector< double > &	vert,
		int	charge,
		const reco::BeamSpot &	bs
	)		const

private

basic method where chi2 is computed

Definition at line 12 of file TrackGenAssociatorByChi2Impl.cc.

References track_associator::trackAssociationChi2().

                                                                       {
   return track_associator::trackAssociationChi2(rParameters, recoTrackCovMatrix,momAtVtx, vert, charge, *theMF, bs);
 }