MuonTrajectoryCleaner.cc

Go to the documentation of this file.

#include "RecoMuon/TrackingTools/interface/MuonTrajectoryCleaner.h"
#include "DataFormats/TrackReco/interface/Track.h"
#include "DataFormats/Math/interface/deltaR.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "DataFormats/Common/interface/RefToBase.h"
#include "DataFormats/Common/interface/AssociationMap.h"
#include "DataFormats/MuonSeed/interface/L2MuonTrajectorySeedCollection.h"
#include "DataFormats/TrackingRecHit/interface/RecSegment.h" 
#include "RecoMuon/TransientTrackingRecHit/interface/MuonTransientTrackingRecHitBreaker.h" 

using namespace std; 

typedef edm::AssociationMap<edm::OneToMany<L2MuonTrajectorySeedCollection, L2MuonTrajectorySeedCollection> > L2SeedAssoc;

void MuonTrajectoryCleaner::clean(TrajectoryContainer& trajC, edm::Event& event, const edm::Handle<edm::View<TrajectorySeed> >& seeds) {
  const std::string metname = "Muon|RecoMuon|MuonTrajectoryCleaner";

  LogTrace(metname) << "Muon Trajectory Cleaner called" << endl;

  TrajectoryContainer::iterator iter, jter;
  Trajectory::DataContainer::const_iterator m1, m2;

  if ( trajC.empty() ) return;
  
  LogTrace(metname) << "Number of trajectories in the container: " <<trajC.size()<< endl;

  int i(0), j(0);
  int match(0);

  // Map between chosen seed and ghost seeds (for trigger)
  map<int, vector<int> > seedmap;

  // CAVEAT: vector<bool> is not a vector, its elements are not addressable!
  // This is fine as long as only operator [] is used as in this case.
  // cf. par 16.3.11
  vector<bool> mask(trajC.size(),true);
  
  TrajectoryContainer result;
  
  for ( iter = trajC.begin(); iter != trajC.end(); iter++ ) {
    if ( !mask[i] ) { i++; continue; }
    if ( !(*iter)->isValid() || (*iter)->empty() ) {mask[i] = false; i++; continue; }
    if(seedmap.count(i)==0) seedmap[i].push_back(i);
    const Trajectory::DataContainer& meas1 = (*iter)->measurements();
    j = i+1;
    bool skipnext=false;
    for ( jter = iter+1; jter != trajC.end(); jter++ ) {
      if ( !mask[j] ) { j++; continue; }
      if(seedmap.count(j)==0) seedmap[j].push_back(j);
      const Trajectory::DataContainer& meas2 = (*jter)->measurements();
      match = 0;
      for( m1 = meas1.begin(); m1 != meas1.end(); m1++ ) {
    for( m2 = meas2.begin(); m2 != meas2.end(); m2++ ) {
      if ( ( (*m1).recHit()->globalPosition() - (*m2).recHit()->globalPosition()).mag()< 10e-5 ) match++; 
    } // end for( m2 ... )
      } // end for( m1 ... )
      
      // FIXME Set Boff/on via cfg!
      double chi2_dof_i = (*iter)->ndof() > 0 ? (*iter)->chiSquared()/(*iter)->ndof() : (*iter)->chiSquared()/1e-10;
      double chi2_dof_j = (*jter)->ndof() > 0 ? (*jter)->chiSquared()/(*jter)->ndof() : (*jter)->chiSquared()/1e-10;

      LogTrace(metname) << " MuonTrajectoryCleaner:";
      LogTrace(metname) << " * trajC " << i 
            << " (pT="<<(*iter)->lastMeasurement().updatedState().globalMomentum().perp() 
            << " GeV) - chi2/nDOF = " << (*iter)->chiSquared() << "/" << (*iter)->ndof() << " = " << chi2_dof_i;
      LogTrace(metname) << "     - valid RH = " << (*iter)->foundHits() << " / total RH = " <<  (*iter)->measurements().size();
      LogTrace(metname) << " * trajC " << j 
            << " (pT="<<(*jter)->lastMeasurement().updatedState().globalMomentum().perp() 
            << " GeV) - chi2/nDOF = " << (*jter)->chiSquared() << "/" << (*jter)->ndof() << " = " << chi2_dof_j;
      LogTrace(metname) << "     - valid RH = " << (*jter)->foundHits() << " / total RH = " << (*jter)->measurements().size();
      LogTrace(metname) << " *** Shared RecHits: " << match; 

      int hit_diff =  (*iter)->foundHits() - (*jter)->foundHits() ;       
      // If there are matches, reject the worst track
      if ( match > 0 ) {
        // If the difference in # of rechits is null then compare the chi2/ndf of the two trajectories
        if ( abs(hit_diff) == 0  ) {

      double minPt = 3.5;
      double dPt = 7.;  // i.e. considering 10% (conservative!) resolution at minPt it is ~ 10 sigma away from the central value

      double maxFraction = 0.95;

          double fraction = (2.*match)/((*iter)->measurements().size()+(*jter)->measurements().size());
      int belowLimit = 0;
      int above = 0;

      if((*jter)->lastMeasurement().updatedState().globalMomentum().perp() <= minPt) ++belowLimit; 
      if((*iter)->lastMeasurement().updatedState().globalMomentum().perp() <= minPt) ++belowLimit; 
     
      if((*jter)->lastMeasurement().updatedState().globalMomentum().perp() >= dPt) ++above; 
      if((*iter)->lastMeasurement().updatedState().globalMomentum().perp() >= dPt) ++above; 
      

      if(fraction >= maxFraction && belowLimit == 1 && above == 1){
        if((*iter)->lastMeasurement().updatedState().globalMomentum().perp() < minPt){
          mask[i] = false;
          skipnext=true;
          seedmap[j].insert(seedmap[j].end(), seedmap[i].begin(), seedmap[i].end());
          seedmap.erase(i);
          LogTrace(metname) << "Trajectory # " << i << " (pT="<<(*iter)->lastMeasurement().updatedState().globalMomentum().perp() 
                << " GeV) rejected because it has too low pt";
        } 
        else {
          mask[j] = false;
          seedmap[i].insert(seedmap[i].end(), seedmap[j].begin(), seedmap[j].end());
          seedmap.erase(j);
          LogTrace(metname) << "Trajectory # " << j << " (pT="<<(*jter)->lastMeasurement().updatedState().globalMomentum().perp() 
                << " GeV) rejected because it has too low pt";
        }
      }
      else{   
        if (chi2_dof_i  > chi2_dof_j) {
          mask[i] = false;
          skipnext=true;
          seedmap[j].insert(seedmap[j].end(), seedmap[i].begin(), seedmap[i].end());
          seedmap.erase(i);
          LogTrace(metname) << "Trajectory # " << i << " (pT="<<(*iter)->lastMeasurement().updatedState().globalMomentum().perp() << " GeV) rejected";
        }
        else{
          mask[j] = false;
          seedmap[i].insert(seedmap[i].end(), seedmap[j].begin(), seedmap[j].end());
          seedmap.erase(j);
          LogTrace(metname) << "Trajectory # " << j << " (pT="<<(*jter)->lastMeasurement().updatedState().globalMomentum().perp() << " GeV) rejected";
        }
      }
    }
        else { // different number of hits
          if ( hit_diff < 0 ) {
            mask[i] = false;
            skipnext=true;
        seedmap[j].insert(seedmap[j].end(), seedmap[i].begin(), seedmap[i].end());
        seedmap.erase(i);
        LogTrace(metname) << "Trajectory # " << i << " (pT="<<(*iter)->lastMeasurement().updatedState().globalMomentum().perp() << " GeV) rejected";
          }
          else { 
        mask[j] = false;
        seedmap[i].insert(seedmap[i].end(), seedmap[j].begin(), seedmap[j].end());
        seedmap.erase(j);
        LogTrace(metname) << "Trajectory # " << j << " (pT="<<(*jter)->lastMeasurement().updatedState().globalMomentum().perp() << " GeV) rejected";
      }
        } 
      }
      if(skipnext) break;
      j++;
    }
    i++;
    if(skipnext) continue;
  }
  

  // Association map between the seed of the chosen trajectory and the seeds of the discarded trajectories
  if(reportGhosts_) {
    LogTrace(metname) << " Creating map between chosen seed and ghost seeds." << std::endl;

    auto seedToSeedsMap = std::make_unique<L2SeedAssoc>();
    if(!seeds->empty()) {
      edm::Ptr<TrajectorySeed> ptr = seeds->ptrAt(0);
      edm::Handle<L2MuonTrajectorySeedCollection> seedsHandle;
      event.get(ptr.id(), seedsHandle);
      seedToSeedsMap = std::make_unique<L2SeedAssoc>(seedsHandle, seedsHandle);
    }

    int seedcnt(0);

    for(map<int, vector<int> >::iterator itmap=seedmap.begin(); itmap!=seedmap.end(); ++itmap, ++seedcnt) {
      edm::RefToBase<TrajectorySeed> tmpSeedRef1 = trajC[(*itmap).first]->seedRef();
      edm::Ref<L2MuonTrajectorySeedCollection> tmpL2SeedRef1 = tmpSeedRef1.castTo<edm::Ref<L2MuonTrajectorySeedCollection> >();

      int tmpsize=(*itmap).second.size();
      for(int cnt=0; cnt!=tmpsize; ++cnt) {
    edm::RefToBase<TrajectorySeed> tmpSeedRef2 = trajC[(*itmap).second[cnt]]->seedRef();
    edm::Ref<L2MuonTrajectorySeedCollection> tmpL2SeedRef2 = tmpSeedRef2.castTo<edm::Ref<L2MuonTrajectorySeedCollection> >();
    seedToSeedsMap->insert(tmpL2SeedRef1, tmpL2SeedRef2);
      }
    }

    event.put(std::move(seedToSeedsMap), "");

  } // end if(reportGhosts_)

  i = 0;
  for ( iter = trajC.begin(); iter != trajC.end(); iter++ ) {
    if ( mask[i] ){
      result.push_back(*iter);
      LogTrace(metname) << "Keep trajectory with pT = " << (*iter)->lastMeasurement().updatedState().globalMomentum().perp() << " GeV";
    }
    else delete *iter;
    i++;
  }

  trajC.clear();
  trajC = result;
}

//
// clean CandidateContainer
//
void MuonTrajectoryCleaner::clean(CandidateContainer& candC){ 
  const std::string metname = "Muon|RecoMuon|MuonTrajectoryCleaner";

  LogTrace(metname) << "Muon Trajectory Cleaner called" << endl;

  if ( candC.size() < 2 ) return;

  CandidateContainer::iterator iter, jter;
  Trajectory::DataContainer::const_iterator m1, m2;

  const float deltaEta = 0.01;
  const float deltaPhi = 0.01;
  const float deltaPt  = 1.0;
  
  LogTrace(metname) << "Number of muon candidates in the container: " <<candC.size()<< endl;

  int i(0), j(0);
  int match(0);
  //unused  bool directionMatch = false;

  // CAVEAT: vector<bool> is not a vector, its elements are not addressable!
  // This is fine as long as only operator [] is used as in this case.
  // cf. par 16.3.11
  vector<bool> mask(candC.size(),true);
  
  CandidateContainer result;
  
  for ( iter = candC.begin(); iter != candC.end(); iter++ ) {
    if ( !mask[i] ) { i++; continue; }
    const Trajectory::DataContainer& meas1 = (*iter)->trajectory()->measurements();
    j = i+1;
    bool skipnext=false;

    TrajectoryStateOnSurface innerTSOS;

    if ((*iter)->trajectory()->direction() == alongMomentum) {
      innerTSOS = (*iter)->trajectory()->firstMeasurement().updatedState();
    } 
    else if ((*iter)->trajectory()->direction() == oppositeToMomentum) { 
      innerTSOS = (*iter)->trajectory()->lastMeasurement().updatedState();
     }
    if ( !(innerTSOS.isValid()) ) continue;
    float pt1 = innerTSOS.globalMomentum().perp();
    float eta1 = innerTSOS.globalMomentum().eta();
    float phi1 = innerTSOS.globalMomentum().phi();

    for ( jter = iter+1; jter != candC.end(); jter++ ) {
      if ( !mask[j] ) { j++; continue; }
      //UNUSED:      directionMatch = false;
      const Trajectory::DataContainer& meas2 = (*jter)->trajectory()->measurements();
      match = 0;
      for ( m1 = meas1.begin(); m1 != meas1.end(); m1++ ) {
        for ( m2 = meas2.begin(); m2 != meas2.end(); m2++ ) {
          if ( (*m1).recHit()->isValid() && (*m2).recHit()->isValid() ) 
        if ( ( (*m1).recHit()->globalPosition() - (*m2).recHit()->globalPosition()).mag()< 10e-5 ) match++;
        }
      }
      
      LogTrace(metname) 
    << " MuonTrajectoryCleaner: candC " << i << " chi2/nRH = " 
    << (*iter)->trajectory()->chiSquared() << "/" << (*iter)->trajectory()->foundHits() <<
    " vs trajC " << j << " chi2/nRH = " << (*jter)->trajectory()->chiSquared() <<
    "/" << (*jter)->trajectory()->foundHits() << " Shared RecHits: " << match;

      TrajectoryStateOnSurface innerTSOS2;       
      if ((*jter)->trajectory()->direction() == alongMomentum) {
        innerTSOS2 = (*jter)->trajectory()->firstMeasurement().updatedState();
      }
      else if ((*jter)->trajectory()->direction() == oppositeToMomentum) {
        innerTSOS2 = (*jter)->trajectory()->lastMeasurement().updatedState();
      }
      if ( !(innerTSOS2.isValid()) ) continue;

      float pt2 = innerTSOS2.globalMomentum().perp();
      float eta2 = innerTSOS2.globalMomentum().eta();
      float phi2 = innerTSOS2.globalMomentum().phi();

      float deta(fabs(eta1-eta2));
      float dphi(fabs(Geom::Phi<float>(phi1)-Geom::Phi<float>(phi2)));
      float dpt(fabs(pt1-pt2));
      if ( dpt < deltaPt && deta < deltaEta && dphi < deltaPhi ) {
    //UNUSED:        directionMatch = true;
        LogTrace(metname)
        << " MuonTrajectoryCleaner: candC " << i<<" and "<<j<< " direction matched: "
        <<innerTSOS.globalMomentum()<<" and " <<innerTSOS2.globalMomentum();
      }

      // If there are matches, reject the worst track
      bool hitsMatch = ((match > 0) && ((match/((*iter)->trajectory()->foundHits()) > 0.25) || (match/((*jter)->trajectory()->foundHits()) > 0.25))) ? true : false;
      bool tracksMatch = 
      ( ( (*iter)->trackerTrack() == (*jter)->trackerTrack() ) && 
        ( deltaR<double>((*iter)->muonTrack()->eta(),(*iter)->muonTrack()->phi(), (*jter)->muonTrack()->eta(),(*jter)->muonTrack()->phi()) < 0.2) );

      //if ( ( tracksMatch ) || (hitsMatch > 0) || directionMatch ) {
            if ( ( tracksMatch ) || (hitsMatch > 0) ) { 
    if (  (*iter)->trajectory()->foundHits() == (*jter)->trajectory()->foundHits() ) {
          if ( (*iter)->trajectory()->chiSquared() > (*jter)->trajectory()->chiSquared() ) {
            mask[i] = false;
            skipnext=true;
          }
          else mask[j] = false;
        }
        else { // different number of hits
          if ( (*iter)->trajectory()->foundHits() < (*jter)->trajectory()->foundHits() ) {
        mask[i] = false;
            skipnext=true;
          }
          else mask[j] = false;
    }
      }
      if(skipnext) break;
      j++;
    }
    i++;
    if(skipnext) continue;
  }
  
  i = 0;
  for ( iter = candC.begin(); iter != candC.end(); iter++ ) {
    if ( mask[i] ) {
       result.push_back(*iter);
    } else {
       delete (*iter)->trajectory();
       delete (*iter)->trackerTrajectory();
       delete *iter;
    } 
    i++;
  }
  
  candC.clear();
  candC = result;
}