EgammaElectronAlgos/src/GsfElectronTools.cc

0001 #include "DataFormats/EgammaCandidates/interface/GsfElectronCore.h"
0002 #include "DataFormats/ParticleFlowReco/interface/GsfPFRecTrack.h"
0003 #include "DataFormats/GsfTrackReco/interface/GsfTrack.h"
0004 #include "DataFormats/EgammaReco/interface/ElectronSeed.h"
0005 #include "RecoEgamma/EgammaElectronAlgos/interface/GsfElectronTools.h"
0006 #include "DataFormats/Math/interface/deltaR.h"
0007
0008 namespace egamma {
0009
0010   using namespace reco;
0011
0012   //=======================================================================================
0013   // Code from Puneeth Kalavase
0014   //=======================================================================================
0015
0016   std::pair<TrackRef, float> getClosestCtfToGsf(GsfTrackRef const& gsfTrackRef,
0017                                                 edm::Handle<reco::TrackCollection> const& ctfTracksH,
0018                                                 edm::soa::EtaPhiTableView trackTable) {
0019     float maxFracShared = 0;
0020     TrackRef ctfTrackRef = TrackRef();
0021     const TrackCollection* ctfTrackCollection = ctfTracksH.product();
0022
0023     float gsfEta = gsfTrackRef->eta();
0024     float gsfPhi = gsfTrackRef->phi();
0025     const HitPattern& gsfHitPattern = gsfTrackRef->hitPattern();
0026
0027     constexpr float dR2 = 0.3 * 0.3;
0028
0029     unsigned int counter = 0;
0030     for (auto ctfTkIter = ctfTrackCollection->begin(); ctfTkIter != ctfTrackCollection->end(); ctfTkIter++, counter++) {
0031       // dont want to look at every single track in the event!
0032       using namespace edm::soa::col;
0033       if (reco::deltaR2(gsfEta, gsfPhi, trackTable.get<Eta>(counter), trackTable.get<Phi>(counter)) > dR2)
0034         continue;
0035
0036       unsigned int shared = 0;
0037       int gsfHitCounter = 0;
0038       int numGsfInnerHits = 0;
0039       int numCtfInnerHits = 0;
0040       // get the CTF Track Hit Pattern
0041       const HitPattern& ctfHitPattern = ctfTkIter->hitPattern();
0042
0043       for (auto elHitsIt = gsfTrackRef->recHitsBegin(); elHitsIt != gsfTrackRef->recHitsEnd();
0044            elHitsIt++, gsfHitCounter++) {
0045         if (!((**elHitsIt).isValid()))  //count only valid Hits
0046         {
0047           continue;
0048         }
0049
0050         // look only in the pixels/TIB/TID
0051         uint32_t gsfHit = gsfHitPattern.getHitPattern(HitPattern::TRACK_HITS, gsfHitCounter);
0052         if (!(HitPattern::pixelHitFilter(gsfHit) || HitPattern::stripTIBHitFilter(gsfHit) ||
0053               HitPattern::stripTIDHitFilter(gsfHit))) {
0054           continue;
0055         }
0056
0057         numGsfInnerHits++;
0058
0059         int ctfHitsCounter = 0;
0060         numCtfInnerHits = 0;
0061         for (auto ctfHitsIt = ctfTkIter->recHitsBegin(); ctfHitsIt != ctfTkIter->recHitsEnd();
0062              ctfHitsIt++, ctfHitsCounter++) {
0063           if (!((**ctfHitsIt).isValid()))  //count only valid Hits!
0064           {
0065             continue;
0066           }
0067
0068           uint32_t ctfHit = ctfHitPattern.getHitPattern(HitPattern::TRACK_HITS, ctfHitsCounter);
0069           if (!(HitPattern::pixelHitFilter(ctfHit) || HitPattern::stripTIBHitFilter(ctfHit) ||
0070                 HitPattern::stripTIDHitFilter(ctfHit))) {
0071             continue;
0072           }
0073
0074           numCtfInnerHits++;
0075
0076           if ((**elHitsIt).sharesInput(&(**ctfHitsIt), TrackingRecHit::all)) {
0077             shared++;
0078             break;
0079           }
0080
0081         }  //ctfHits iterator
0082
0083       }  //gsfHits iterator
0084
0085       if ((numGsfInnerHits == 0) || (numCtfInnerHits == 0)) {
0086         continue;
0087       }
0088
0089       if (static_cast<float>(shared) / std::min(numGsfInnerHits, numCtfInnerHits) > maxFracShared) {
0090         maxFracShared = static_cast<float>(shared) / std::min(numGsfInnerHits, numCtfInnerHits);
0091         ctfTrackRef = TrackRef(ctfTracksH, counter);
0092       }
0093
0094     }  //ctfTrack iterator
0095
0096     return {ctfTrackRef, maxFracShared};
0097   }
0098
0099 }  // namespace egamma