ZMuMuAnalyzer Class Reference

Inheritance diagram for ZMuMuAnalyzer:

Classes
class	ZMuMuAnalyzer

Public Member Functions
	ZMuMuAnalyzer (const edm::ParameterSet &pset)
Public Member Functions inherited from edm::EDAnalyzer
void	callWhenNewProductsRegistered (std::function< void(BranchDescription const &)> const &func)
	EDAnalyzer ()
ModuleDescription const &	moduleDescription () const
std::string	workerType () const
virtual	~EDAnalyzer ()
Public Member Functions inherited from edm::EDConsumerBase
std::vector< ConsumesInfo >	consumesInfo () const
	EDConsumerBase ()
ProductHolderIndexAndSkipBit	indexFrom (EDGetToken, BranchType, TypeID const &) const
void	itemsMayGet (BranchType, std::vector< ProductHolderIndexAndSkipBit > &) const
void	itemsToGet (BranchType, std::vector< ProductHolderIndexAndSkipBit > &) const
std::vector < ProductHolderIndexAndSkipBit > const &	itemsToGetFromEvent () const
void	labelsForToken (EDGetToken iToken, Labels &oLabels) const
void	modulesDependentUpon (const std::string &iProcessName, std::vector< const char * > &oModuleLabels) const
void	modulesWhoseProductsAreConsumed (std::vector< ModuleDescription const * > &modules, ProductRegistry const &preg, std::map< std::string, ModuleDescription const * > const &labelsToDesc, std::string const &processName) const
bool	registeredToConsume (ProductHolderIndex, bool, BranchType) const
bool	registeredToConsumeMany (TypeID const &, BranchType) const
void	updateLookup (BranchType iBranchType, ProductHolderIndexHelper const &)
virtual	~EDConsumerBase ()

Private Member Functions
virtual void	analyze (const edm::Event &event, const edm::EventSetup &setup) override
virtual void	endJob () override

Private Attributes
double	etacut_
TH1D *	h_zMuMu_mass_
TH1D *	h_zMuMuMatched_mass_
TH1D *	h_zMuSingleStandAlone_mass_
TH1D *	h_zMuSingleStandAloneMatched_mass_
TH1D *	h_zMuSingleStandAloneOverlap_mass_
TH1D *	h_zMuSingleStandAloneOverlapMatched_mass_
TH1D *	h_zMuSingleTrack_mass_
TH1D *	h_zMuSingleTrackMatched_mass_
double	isocut_
double	maxZmass_
double	minZmass_
EDGetTokenT< IsolationCollection >	muIsoToken_
OverlapChecker	overlap_
double	ptcut_
double	ptSTAcut_
EDGetTokenT< IsolationCollection >	standAloneIsoToken_
EDGetTokenT< IsolationCollection >	trackIsoToken_
EDGetTokenT< CandMatchMap >	zMuMuMapToken_
EDGetTokenT< CandidateCollection >	zMuMuToken_
EDGetTokenT< CandMatchMap >	zMuStandAloneMapToken_
EDGetTokenT< CandidateCollection >	zMuStandAloneToken_
EDGetTokenT< CandMatchMap >	zMuTrackMapToken_
EDGetTokenT< CandidateCollection >	zMuTrackToken_

Additional Inherited Members
Public Types inherited from edm::EDAnalyzer
typedef EDAnalyzer	ModuleType
Public Types inherited from edm::EDConsumerBase
typedef ProductLabels	Labels
Static Public Member Functions inherited from edm::EDAnalyzer
static const std::string &	baseType ()
static void	fillDescriptions (ConfigurationDescriptions &descriptions)
static void	prevalidate (ConfigurationDescriptions &)
Protected Member Functions inherited from edm::EDConsumerBase
template<typename ProductType , BranchType B = InEvent>
EDGetTokenT< ProductType >	consumes (edm::InputTag const &tag)
EDGetToken	consumes (const TypeToGet &id, edm::InputTag const &tag)
template<BranchType B>
EDGetToken	consumes (TypeToGet const &id, edm::InputTag const &tag)
ConsumesCollector	consumesCollector ()
	Use a ConsumesCollector to gather consumes information from helper functions. More...
template<typename ProductType , BranchType B = InEvent>
void	consumesMany ()
void	consumesMany (const TypeToGet &id)
template<BranchType B>
void	consumesMany (const TypeToGet &id)
template<typename ProductType , BranchType B = InEvent>
EDGetTokenT< ProductType >	mayConsume (edm::InputTag const &tag)
EDGetToken	mayConsume (const TypeToGet &id, edm::InputTag const &tag)
template<BranchType B>
EDGetToken	mayConsume (const TypeToGet &id, edm::InputTag const &tag)

Detailed Description

Definition at line 40 of file ZMuMuAnalyzer.cc.

Constructor & Destructor Documentation

ZMuMuAnalyzer::ZMuMuAnalyzer

(

const edm::ParameterSet &

pset

)

Definition at line 65 of file ZMuMuAnalyzer.cc.

References h_zMuMu_mass_, h_zMuMuMatched_mass_, h_zMuSingleStandAlone_mass_, h_zMuSingleStandAloneMatched_mass_, h_zMuSingleStandAloneOverlap_mass_, h_zMuSingleStandAloneOverlapMatched_mass_, h_zMuSingleTrack_mass_, h_zMuSingleTrackMatched_mass_, and TFileService::make().

                                                        :
  zMuMuToken_( consumes< CandidateCollection >( pset.getParameter<InputTag>( "zMuMu" ) ) ),
  zMuTrackToken_( consumes< CandidateCollection >( pset.getParameter<InputTag>( "zMuTrack" ) ) ),
  zMuStandAloneToken_( consumes< CandidateCollection >( pset.getParameter<InputTag>( "zMuStandAlone" ) ) ),
  muIsoToken_( consumes< IsolationCollection >( pset.getParameter<InputTag>( "muIso" ) ) ),
  trackIsoToken_( consumes< IsolationCollection >( pset.getParameter<InputTag>( "trackIso" ) ) ),
  standAloneIsoToken_( consumes< IsolationCollection >( pset.getParameter<InputTag>( "standAloneIso" ) ) ),
  zMuMuMapToken_( mayConsume< CandMatchMap >( pset.getParameter<InputTag>( "zMuMuMap" ) ) ),
  zMuTrackMapToken_( mayConsume< CandMatchMap >( pset.getParameter<InputTag>( "zMuTrackMap" ) ) ),
  zMuStandAloneMapToken_( mayConsume< CandMatchMap >( pset.getParameter<InputTag>( "zMuStandAloneMap" ) ) ),
  isocut_( pset.getParameter<double>( "isocut" ) ),
  etacut_( pset.getParameter<double>( "etacut" ) ),
  ptcut_( pset.getParameter<double>( "ptcut" ) ),
  ptSTAcut_( pset.getParameter<double>( "ptSTAcut" ) ),

  minZmass_( pset.getParameter<double>( "minZmass" )),
  maxZmass_( pset.getParameter<double>( "maxZmass" )) {

  Service<TFileService> fs;
  h_zMuMu_mass_ = fs->make<TH1D>( "ZMuMumass", "ZMuMu mass(GeV)", 200,  0., 200. );
  h_zMuSingleTrack_mass_ = fs->make<TH1D>( "ZMuSingleTrackmass", "ZMuSingleTrack mass(GeV)", 100,  0., 200. );
  h_zMuSingleStandAlone_mass_ = fs->make<TH1D>( "ZMuSingleStandAlonemass", "ZMuSingleStandAlone mass(GeV)", 50,  0., 200. );
  h_zMuSingleStandAloneOverlap_mass_ = fs->make<TH1D>( "ZMuSingleStandAloneOverlapmass", "ZMuSingleStandAloneOverlap  mass(GeV)", 50,  0., 200. );


  h_zMuMuMatched_mass_ = fs->make<TH1D>( "ZMuMuMatchedmass", "ZMuMu Matched  mass(GeV)", 200,  0., 200. );
  h_zMuSingleTrackMatched_mass_ = fs->make<TH1D>( "ZMuSingleTrackmassMatched", "ZMuSingleTrackMatched mass(GeV)", 100,  0., 200. );
  h_zMuSingleStandAloneMatched_mass_ = fs->make<TH1D>( "ZMuSingleStandAlonemassMatched", "ZMuSingleStandAloneMatched mass(GeV)", 50,  0., 200. );
  h_zMuSingleStandAloneOverlapMatched_mass_ = fs->make<TH1D>( "ZMuSingleStandAloneOverlapmassMatched", "ZMuSingleStandAloneMatched Overlap  mass(GeV)", 50,  0., 200. );
}

Member Function Documentation

void ZMuMuAnalyzer::analyze ( const edm::Event &  event, const edm::EventSetup &  setup  )

overrideprivatevirtual

Implements edm::EDAnalyzer.

Definition at line 96 of file ZMuMuAnalyzer.cc.

References edm::RefToBase< T >::castTo(), reco::Candidate::daughter(), etacut_, h_zMuMu_mass_, h_zMuMuMatched_mass_, h_zMuSingleStandAlone_mass_, h_zMuSingleStandAloneMatched_mass_, h_zMuSingleStandAloneOverlap_mass_, h_zMuSingleStandAloneOverlapMatched_mass_, h_zMuSingleTrack_mass_, h_zMuSingleTrackMatched_mass_, i, edm::ProductID::id(), edm::HandleBase::id(), edm::Ref< C, T, F >::id(), isocut_, j, edm::Ref< C, T, F >::key(), RazorAnalyzer::lep1, RazorAnalyzer::lep2, visualization-live-secondInstance_cfg::m, reco::Candidate::mass(), reco::Candidate::masterClone(), maxZmass_, minZmass_, AnalysisDataFormats_SUSYBSMObjects::ms, muIsoToken_, overlap_, ptcut_, ptSTAcut_, standAloneIsoToken_, trackIsoToken_, ZMuMuAnalysisNtupler_cff::zMuMu, zMuMuMapToken_, zMuMuToken_, zMuStandAloneMapToken_, zMuStandAloneToken_, zMuTrackMapToken_, and zMuTrackToken_.

                                                                             {
  Handle<CandidateCollection> zMuMu;
  event.getByToken(zMuMuToken_, zMuMu);
  Handle<CandidateCollection> zMuTrack;
  event.getByToken( zMuTrackToken_, zMuTrack );
  Handle<CandidateCollection> zMuStandAlone;
  event.getByToken( zMuStandAloneToken_, zMuStandAlone );

  unsigned int nZMuMu = zMuMu->size();
  unsigned int nZTrackMu = zMuTrack->size();
  unsigned int nZStandAloneMu = zMuStandAlone->size();
  static const double zMass = 91.1876; // PDG Z mass

  //  cout << "nZMuMu = " << nZMuMu << endl;
  //  cout << "nZTrackMu = " << nZTrackMu << endl;
  //  cout << "nZStandAloneMu = " << nZStandAloneMu << endl;

  Handle<CandMatchMap> zMuMuMap;
  if( nZMuMu > 0 ) {
    event.getByToken(zMuMuMapToken_, zMuMuMap);
  }

  Handle<CandMatchMap> zMuTrackMap;
  if( nZTrackMu > 0 ) {
    event.getByToken( zMuTrackMapToken_, zMuTrackMap );
  }

  Handle<CandMatchMap> zMuStandAloneMap;
  if( nZStandAloneMu > 0 ) {
    event.getByToken( zMuStandAloneMapToken_, zMuStandAloneMap );
  }

  Handle<IsolationCollection> muIso;
  event.getByToken(muIsoToken_, muIso);
  ProductID muIsoId = muIso->keyProduct().id();
  Handle<IsolationCollection> trackIso;
  event.getByToken(trackIsoToken_, trackIso);
  ProductID trackIsoId = trackIso->keyProduct().id();

  Handle<IsolationCollection> standAloneIso;
  event.getByToken(standAloneIsoToken_, standAloneIso);
  ProductID standAloneIsoId = standAloneIso->keyProduct().id();

  if (nZMuMu > 0) {
    double mass = 1000000.;
    for( unsigned int i = 0; i < nZMuMu; i++ ) {
      const Candidate & zmmCand = (*zMuMu)[ i ];
      CandidateRef CandRef(zMuMu,i);
      CandidateRef lep1 = zmmCand.daughter( 0 )->masterClone().castTo<CandidateRef>();
      CandidateRef lep2 = zmmCand.daughter( 1 )->masterClone().castTo<CandidateRef>();

      const  double iso1 = muIso->value( lep1.key() );
      const  double iso2 = muIso->value( lep2.key() );

      double m = zmmCand.mass();
      if (lep1->pt()>ptcut_ && lep2->pt()>ptcut_ &&
      fabs(lep1->eta())<etacut_ && fabs(lep2->eta())<etacut_ &&
      m>minZmass_ && m<maxZmass_ && iso1 < isocut_ && iso2 <isocut_) {
    if ( fabs( mass - zMass ) > fabs( m - zMass ) ) {
      mass = m;
    }

    h_zMuMu_mass_->Fill( mass );
    CandMatchMap::const_iterator m0 = zMuMuMap->find(CandRef);
    if( m0 != zMuMuMap->end()) {
        h_zMuMuMatched_mass_->Fill( mass );
    }
      }
    }
  }

  //ZmuSingleTRack
  if (nZMuMu ==0 && nZTrackMu>0) {
    for( unsigned int j = 0; j < nZTrackMu; j++ ) {
      const Candidate & ztmCand = (*zMuTrack)[ j ];
      CandidateRef CandRef(zMuTrack,j);
      CandidateRef lep1 = ztmCand.daughter( 0 )->masterClone().castTo<CandidateRef>();
      CandidateRef lep2 = ztmCand.daughter( 1 )->masterClone().castTo<CandidateRef>();

      ProductID id1 = lep1.id();
      ProductID id2 = lep2.id();
      double iso1 = -1;
      double iso2 = -1;

      if( id1 == muIsoId )
    iso1 = muIso->value( lep1.key() );
      else if ( id1 == trackIsoId )
    iso1 = trackIso->value( lep1.key() );

      if( id2 == muIsoId )
          iso2 = muIso->value( lep2.key() );
      else if ( id2 == trackIsoId )
    iso2 = trackIso->value( lep2.key() );

      double mt = ztmCand.mass();
      if (lep1->pt()>ptcut_ && lep2->pt()>ptcut_ &&
      fabs(lep1->eta())<etacut_ && fabs(lep2->eta())<etacut_ &&
      mt>minZmass_ && mt<maxZmass_ && iso1<isocut_ && iso2 <isocut_) {
    h_zMuSingleTrack_mass_->Fill( mt );
    CandMatchMap::const_iterator m0 = zMuTrackMap->find(CandRef);
    if( m0 != zMuTrackMap->end()) {
      h_zMuSingleTrackMatched_mass_->Fill( mt );
    }
      }
    }
  }

  //ZmuSingleStandAlone
  if (nZMuMu ==0 && nZStandAloneMu>0) {
    //      unsigned int index = 1000;
    for( unsigned int j = 0; j < nZStandAloneMu; j++ ) {
      const Candidate & zsmCand = (*zMuStandAlone)[ j ];
      CandidateRef CandRef(zMuStandAlone,j);
      CandidateRef lep1 = zsmCand.daughter( 0 )->masterClone().castTo<CandidateRef>();
      CandidateRef lep2 = zsmCand.daughter( 1 )->masterClone().castTo<CandidateRef>();

      ProductID id1 = lep1.id();
      ProductID id2 = lep2.id();
      double iso1 = -1;
      double iso2 = -1;

      if( id1 == muIsoId )
    iso1 = muIso->value( lep1.key() );
      else if ( id1 == standAloneIsoId )
    iso1 = standAloneIso->value( lep1.key() );

      if( id2 == muIsoId )
    iso2 = muIso->value( lep2.key() );
      else if ( id2 == standAloneIsoId )
    iso2 = standAloneIso->value( lep2.key() );

      double ms = zsmCand.mass();
      if (lep1->pt()>ptSTAcut_ && lep2->pt()>ptSTAcut_ &&
      fabs(lep1->eta())<etacut_ && fabs(lep2->eta())<etacut_ &&
      ms>minZmass_ && ms<maxZmass_ && iso1<isocut_ && iso2 <isocut_) {
    h_zMuSingleStandAlone_mass_->Fill( ms );
    CandMatchMap::const_iterator m0 = zMuStandAloneMap->find(CandRef);
    if( m0 != zMuStandAloneMap->end()) {
      h_zMuSingleStandAloneMatched_mass_->Fill( ms );
    }

    bool noOverlap = true;
    for( unsigned int j = 0; j < zMuTrack->size(); j++ ) {
      const Candidate & ztmCand = (*zMuTrack)[ j ];
      CandidateRef CandReft(zMuTrack,j);

      CandidateRef lep1 = ztmCand.daughter( 0 )->masterClone().castTo<CandidateRef>();
      CandidateRef lep2 = ztmCand.daughter( 1 )->masterClone().castTo<CandidateRef>();

      ProductID id1 = lep1.id();
      ProductID id2 = lep2.id();
      double iso1 = -1;
      double iso2 = -1;

      if( id1 == muIsoId )
        iso1 = muIso->value( lep1.key() );
      else if ( id1 == trackIsoId )
        iso1 = trackIso->value( lep1.key() );

      if( id2 == muIsoId )
        iso2 = muIso->value( lep2.key() );
      else if ( id2 == trackIsoId )
        iso2 = trackIso->value( lep2.key() );

      double mt = ztmCand.mass();
      if (lep1->pt()>ptcut_ && lep2->pt()>ptcut_ &&
          fabs(lep1->eta())<etacut_ && fabs(lep2->eta())<etacut_ &&
          mt>minZmass_ && mt<maxZmass_ && iso1<isocut_ && iso2 <isocut_) {

        if ( overlap_( ztmCand, zsmCand ) ) {
          noOverlap = false;
          break;
        }
        if (!noOverlap ) {
          h_zMuSingleStandAloneOverlap_mass_->Fill( ms );
          CandMatchMap::const_iterator m1 = zMuTrackMap->find(CandReft);
          CandMatchMap::const_iterator m2 = zMuStandAloneMap->find(CandRef);

          if( m1 != zMuTrackMap->end()  && m2 != zMuStandAloneMap->end()  ) {
        h_zMuSingleStandAloneOverlapMatched_mass_->Fill( ms );
          }
        }
      }
    }
      }
    }
  }
}

void ZMuMuAnalyzer::endJob ( void  )

overrideprivatevirtual

Reimplemented from edm::EDAnalyzer.

Definition at line 285 of file ZMuMuAnalyzer.cc.

References gather_cfg::cout, h_zMuMu_mass_, h_zMuMuMatched_mass_, h_zMuSingleStandAlone_mass_, h_zMuSingleStandAloneMatched_mass_, h_zMuSingleStandAloneOverlap_mass_, h_zMuSingleStandAloneOverlapMatched_mass_, h_zMuSingleTrack_mass_, and h_zMuSingleTrackMatched_mass_.

                           {
  double Nzmm = h_zMuMu_mass_->GetEntries() ;
  double Nzsm = h_zMuSingleStandAlone_mass_->GetEntries()  ;
  double Nzsnom = h_zMuSingleStandAloneOverlap_mass_->GetEntries()  ;
  double Nztm = h_zMuSingleTrack_mass_->GetEntries();

  double NzmmMatch = h_zMuMuMatched_mass_->GetEntries() ;
  double NzsmMatch = h_zMuSingleStandAloneMatched_mass_->GetEntries()  ;
  double NzsnomMatch = h_zMuSingleStandAloneOverlapMatched_mass_->GetEntries()  ;
  double NztmMatch = h_zMuSingleTrackMatched_mass_->GetEntries();

  cout<<"-- N SingleTrackMu = "<<Nztm<<endl;
  cout<<"-----N SinglStandAloneMu = "<<Nzsm<<endl;
  cout<<"-----N SingleStandAloneOverlapMu = "<<Nzsnom<<endl;
  cout<<"------- N MuMu = "<<Nzmm<<endl;

  cout<<"-- N SingleTrackMuMatched = "<<NztmMatch<<endl;
  cout<<"-----N SinglStandAloneMuMatched = "<<NzsmMatch<<endl;
  cout<<"-----N SingleStandAloneOverlapMuMatched  = "<<NzsnomMatch<<endl;
  cout<<"------- N MuMu Matched  = "<<NzmmMatch<<endl;
}

Member Data Documentation

double ZMuMuAnalyzer::etacut_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

TH1D* ZMuMuAnalyzer::h_zMuMu_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuMuMatched_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleStandAlone_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleStandAloneMatched_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleStandAloneOverlap_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleStandAloneOverlapMatched_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleTrack_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

TH1D * ZMuMuAnalyzer::h_zMuSingleTrackMatched_mass_

private

Definition at line 58 of file ZMuMuAnalyzer.cc.

Referenced by analyze(), endJob(), and ZMuMuAnalyzer().

double ZMuMuAnalyzer::isocut_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

double ZMuMuAnalyzer::maxZmass_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

double ZMuMuAnalyzer::minZmass_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<IsolationCollection> ZMuMuAnalyzer::muIsoToken_

private

Definition at line 51 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

OverlapChecker ZMuMuAnalyzer::overlap_

private

Definition at line 47 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

double ZMuMuAnalyzer::ptcut_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

double ZMuMuAnalyzer::ptSTAcut_

private

Definition at line 57 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<IsolationCollection> ZMuMuAnalyzer::standAloneIsoToken_

private

Definition at line 53 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<IsolationCollection> ZMuMuAnalyzer::trackIsoToken_

private

Definition at line 52 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandMatchMap> ZMuMuAnalyzer::zMuMuMapToken_

private

Definition at line 54 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandidateCollection> ZMuMuAnalyzer::zMuMuToken_

private

Definition at line 48 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandMatchMap> ZMuMuAnalyzer::zMuStandAloneMapToken_

private

Definition at line 56 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandidateCollection> ZMuMuAnalyzer::zMuStandAloneToken_

private

Definition at line 50 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandMatchMap> ZMuMuAnalyzer::zMuTrackMapToken_

private

Definition at line 55 of file ZMuMuAnalyzer.cc.

Referenced by analyze().

EDGetTokenT<CandidateCollection> ZMuMuAnalyzer::zMuTrackToken_

private

Definition at line 49 of file ZMuMuAnalyzer.cc.

Referenced by analyze().