TrackAssociatorByChi2Impl Class Reference

#include <TrackAssociatorByChi2Impl.h>

Inheritance diagram for TrackAssociatorByChi2Impl:

Public Types
typedef std::map< double, SimTrack >	Chi2SimMap
typedef std::pair< reco::Track, Chi2SimMap >	RecoToSimPair
typedef std::vector< RecoToSimPair >	RecoToSimPairAssociation

Public Member Functions
reco::RecoToSimCollection	associateRecoToSim (const edm::RefToBaseVector< reco::Track > &, const edm::RefVector< TrackingParticleCollection > &) const override
	Association Reco To Sim with Collections. More...
reco::RecoToSimCollection	associateRecoToSim (const edm::Handle< edm::View< reco::Track > > &tCH, const edm::Handle< TrackingParticleCollection > &tPCH) const override
	compare reco to sim the handle of reco::Track and TrackingParticle collections More...
reco::SimToRecoCollection	associateSimToReco (const edm::RefToBaseVector< reco::Track > &, const edm::RefVector< TrackingParticleCollection > &) const override
	Association Sim To Reco with Collections. More...
reco::SimToRecoCollection	associateSimToReco (const edm::Handle< edm::View< reco::Track > > &tCH, const edm::Handle< TrackingParticleCollection > &tPCH) const override
	compare reco to sim the handle of reco::Track and TrackingParticle collections More...
	TrackAssociatorByChi2Impl (const MagneticField &mF, const reco::BeamSpot &bs, double chi2Cut, bool onlyDiag)
	Constructor. More...
Public Member Functions inherited from reco::TrackToTrackingParticleAssociatorBaseImpl
virtual reco::RecoToSimCollection	associateRecoToSim (const edm::Handle< edm::View< reco::Track >> &tCH, const edm::Handle< TrackingParticleCollection > &tPCH) const
virtual reco::RecoToSimCollectionSeed	associateRecoToSim (const edm::Handle< edm::View< TrajectorySeed >> &, const edm::Handle< TrackingParticleCollection > &) const
virtual reco::RecoToSimCollectionTCandidate	associateRecoToSim (const edm::Handle< TrackCandidateCollection > &, const edm::Handle< TrackingParticleCollection > &) const
virtual reco::SimToRecoCollection	associateSimToReco (const edm::Handle< edm::View< reco::Track >> &tCH, const edm::Handle< TrackingParticleCollection > &tPCH) const
virtual reco::SimToRecoCollectionSeed	associateSimToReco (const edm::Handle< edm::View< TrajectorySeed >> &, const edm::Handle< TrackingParticleCollection > &) const
virtual reco::SimToRecoCollectionTCandidate	associateSimToReco (const edm::Handle< TrackCandidateCollection > &, const edm::Handle< TrackingParticleCollection > &) const
	TrackToTrackingParticleAssociatorBaseImpl ()
	Constructor. More...
virtual	~TrackToTrackingParticleAssociatorBaseImpl ()
	Destructor. More...

Private Member Functions
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/TrackAssociatorByChi2.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 34 of file TrackAssociatorByChi2Impl.h.

Member Typedef Documentation

typedef std::map<double, SimTrack> TrackAssociatorByChi2Impl::Chi2SimMap

Definition at line 36 of file TrackAssociatorByChi2Impl.h.

typedef std::pair<reco::Track, Chi2SimMap> TrackAssociatorByChi2Impl::RecoToSimPair

Definition at line 37 of file TrackAssociatorByChi2Impl.h.

typedef std::vector<RecoToSimPair> TrackAssociatorByChi2Impl::RecoToSimPairAssociation

Definition at line 38 of file TrackAssociatorByChi2Impl.h.

Constructor & Destructor Documentation

TrackAssociatorByChi2Impl::TrackAssociatorByChi2Impl ( const MagneticField &  mF, const reco::BeamSpot &  bs, double  chi2Cut, bool  onlyDiag  )

inline

Constructor.

Definition at line 55 of file TrackAssociatorByChi2Impl.h.

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

Member Function Documentation

RecoToSimCollection TrackAssociatorByChi2Impl::associateRecoToSim ( const edm::RefToBaseVector< reco::Track > &  tC, const edm::RefVector< TrackingParticleCollection > &  tPCH  ) const

overridevirtual

Association Reco To Sim with Collections.

Implements reco::TrackToTrackingParticleAssociatorBaseImpl.

Definition at line 21 of file TrackAssociatorByChi2Impl.cc.

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

                                                                                                         {
  const reco::BeamSpot& bs = *theBeamSpot;

  RecoToSimCollection outputCollection;

  //dereference the edm::Refs only once
  std::vector<TrackingParticle 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) {
        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::RecoToSimCollection TrackAssociatorByChi2Impl::associateRecoToSim ( const edm::Handle< edm::View< reco::Track > > &  tCH, const edm::Handle< TrackingParticleCollection > &  tPCH  ) const

inlineoverride

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

Definition at line 69 of file TrackAssociatorByChi2Impl.h.

References reco::TrackToTrackingParticleAssociatorBaseImpl::associateRecoToSim().

                                                                                                                 {
    return TrackToTrackingParticleAssociatorBaseImpl::associateRecoToSim(tCH, tPCH);
  }

SimToRecoCollection TrackAssociatorByChi2Impl::associateSimToReco ( const edm::RefToBaseVector< reco::Track > &  tC, const edm::RefVector< TrackingParticleCollection > &  tPCH  ) const

overridevirtual

Association Sim To Reco with Collections.

Implements reco::TrackToTrackingParticleAssociatorBaseImpl.

Definition at line 80 of file TrackAssociatorByChi2Impl.cc.

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

                                                                                                         {
  const reco::BeamSpot& bs = *theBeamSpot;

  SimToRecoCollection 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::SimToRecoCollection TrackAssociatorByChi2Impl::associateSimToReco ( const edm::Handle< edm::View< reco::Track > > &  tCH, const edm::Handle< TrackingParticleCollection > &  tPCH  ) const

inlineoverride

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

Definition at line 76 of file TrackAssociatorByChi2Impl.h.

References reco::TrackToTrackingParticleAssociatorBaseImpl::associateSimToReco(), and ALCARECOTkAlJpsiMuMu_cff::charge.

                                                                                                                 {
    return TrackToTrackingParticleAssociatorBaseImpl::associateSimToReco(tCH, tPCH);
  }

double TrackAssociatorByChi2Impl::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 TrackAssociatorByChi2Impl.cc.

References track_associator::trackAssociationChi2().

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

Member Data Documentation

double TrackAssociatorByChi2Impl::chi2cut

private

Definition at line 92 of file TrackAssociatorByChi2Impl.h.

bool TrackAssociatorByChi2Impl::onlyDiagonal

private

Definition at line 93 of file TrackAssociatorByChi2Impl.h.

const reco::BeamSpot* TrackAssociatorByChi2Impl::theBeamSpot

private

Definition at line 91 of file TrackAssociatorByChi2Impl.h.

const MagneticField* TrackAssociatorByChi2Impl::theMF

private

Definition at line 90 of file TrackAssociatorByChi2Impl.h.