TrackAssociation/src/trackAssociationChi2.cc

0001 #include "DataFormats/Math/interface/deltaPhi.h"
0002 #include "FWCore/MessageLogger/interface/MessageLogger.h"
0003 #include "SimTracker/TrackAssociation/interface/trackAssociationChi2.h"
0004 #include "TrackingTools/PatternTools/interface/trackingParametersAtClosestApproachToBeamSpot.h"
0005
0006 namespace track_associator {
0007   constexpr double invalidChi2 = 10000000000.;
0008
0009   double trackAssociationChi2(const reco::TrackBase::ParameterVector &rParameters,
0010                               const reco::TrackBase::CovarianceMatrix &recoTrackCovMatrix,
0011                               const reco::TrackBase::ParameterVector &sParameters) {
0012     double chi2 = invalidChi2;
0013
0014     reco::TrackBase::ParameterVector diffParameters = rParameters - sParameters;
0015     diffParameters[2] = reco::deltaPhi(diffParameters[2], 0.f);
0016     chi2 = ROOT::Math::Dot(diffParameters * recoTrackCovMatrix, diffParameters);
0017     chi2 /= 5;
0018
0019     LogDebug("TrackAssociator") << "====NEW RECO TRACK WITH PT=" << sin(rParameters[1]) / rParameters[0] << "====\n"
0020                                 << "qoverp sim: " << sParameters[0] << "\n"
0021                                 << "lambda sim: " << sParameters[1] << "\n"
0022                                 << "phi    sim: " << sParameters[2] << "\n"
0023                                 << "dxy    sim: " << sParameters[3] << "\n"
0024                                 << "dsz    sim: " << sParameters[4] << "\n"
0025                                 << ": " /*<< */ << "\n"
0026                                 << "qoverp rec: " << rParameters[0] << "\n"
0027                                 << "lambda rec: " << rParameters[1] << "\n"
0028                                 << "phi    rec: " << rParameters[2] << "\n"
0029                                 << "dxy    rec: " << rParameters[3] << "\n"
0030                                 << "dsz    rec: " << rParameters[4] << "\n"
0031                                 << ": " /*<< */ << "\n"
0032                                 << "chi2: " << chi2 << "\n";
0033     return chi2;
0034   }
0035
0036   double trackAssociationChi2(const reco::TrackBase::ParameterVector &rParameters,
0037                               const reco::TrackBase::CovarianceMatrix &recoTrackCovMatrix,
0038                               const Basic3DVector<double> &momAtVtx,
0039                               const Basic3DVector<double> &vert,
0040                               int charge,
0041                               const MagneticField &magfield,
0042                               const reco::BeamSpot &bs) {
0043     double chi2 = invalidChi2;
0044
0045     std::pair<bool, reco::TrackBase::ParameterVector> params =
0046         reco::trackingParametersAtClosestApproachToBeamSpot(vert, momAtVtx, charge, magfield, bs);
0047     if (params.first) {
0048       return trackAssociationChi2(rParameters, recoTrackCovMatrix, params.second);
0049     }
0050     return chi2;
0051   }
0052
0053   double trackAssociationChi2(const reco::TrackBase::ParameterVector &rParameters,
0054                               const reco::TrackBase::CovarianceMatrix &recoTrackCovMatrix,
0055                               const TrackingParticle &trackingParticle,
0056                               const MagneticField &magfield,
0057                               const reco::BeamSpot &bs) {
0058     const int charge = trackingParticle.charge();
0059     if (charge == 0)
0060       return invalidChi2;
0061
0062     const auto tpMom = trackingParticle.momentum();
0063     Basic3DVector<double> momAtVtx(tpMom.x(), tpMom.y(), tpMom.z());
0064     Basic3DVector<double> vert(trackingParticle.vertex());
0065
0066     return trackAssociationChi2(rParameters, recoTrackCovMatrix, momAtVtx, vert, charge, magfield, bs);
0067   }
0068
0069   double trackAssociationChi2(const reco::TrackBase &track,
0070                               const TrackingParticle &trackingParticle,
0071                               const MagneticField &magfield,
0072                               const reco::BeamSpot &bs) {
0073     auto cov = track.covariance();
0074     cov.Invert();
0075
0076     return trackAssociationChi2(track.parameters(), cov, trackingParticle, magfield, bs);
0077   }
0078 }  // namespace track_associator