CandMassKinFitter Struct Reference

#include <CandMassKinFitter.h>

List of all members.

Public Member Functions
	CandMassKinFitter (double m)
reco::FitQuality	set (reco::Candidate &) const
Private Attributes
double	mass_

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Detailed Description

Definition at line 6 of file CandMassKinFitter.h.

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Constructor & Destructor Documentation

CandMassKinFitter::CandMassKinFitter

(

double

m

)

[inline, explicit]

Definition at line 7 of file CandMassKinFitter.h.

: mass_( m ) { }

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Member Function Documentation

FitQuality CandMassKinFitter::set

(

reco::Candidate &

c

)

const

Definition at line 11 of file CandMassKinFitter.cc.

References TKinFitter::addConstraint(), TKinFitter::addMeasParticle(), TFitConstraintM::addParticle1(), reco::Candidate::daughter(), ExpressReco_HICollisions_FallBack::e, ExpressReco_HICollisions_FallBack::errors, TKinFitter::fit(), reco::Candidate::get(), TAbsFitParticle::getCurr4Vec(), TKinFitter::getNDF(), TKinFitter::getS(), i, reco::Candidate::mass(), AlCaRecoCosmics_cfg::name, reco::Candidate::numberOfDaughters(), reco::Candidate::p4(), p4, TKinFitter::setMaxDeltaS(), TKinFitter::setMaxF(), TKinFitter::setMaxNbIter(), reco::Candidate::setP4(), and TKinFitter::setVerbosity().

Referenced by MassKinFitterCandProducer::produce().

                                                       {
  TKinFitter fitter("CandMassFit", "CandMassFit");
  TString name("dau0");
  size_t daus = c.numberOfDaughters();
  vector<TMatrixD> errors(daus, TMatrix(3,3));
  vector<TVector3> momenta(daus);
  vector<TFitParticleMCCart *> particles(daus, 0);
  TFitConstraintM constraint( "MassConstraint", 
                              "MassConstraint", 0, 0 , mass_);
  for ( size_t i = 0; i < daus; ++ i ) {
    const Candidate & dau = * c.daughter( i );
    Particle::LorentzVector p4 = dau.p4();
    TMatrixD & err = errors[i];
    TVector3 & mom = momenta[i];
    mom = TVector3( p4.px(), p4.py(), p4.pz() );
    TrackRef trk = dau.get<TrackRef>();
    // dummy errors for now...
    // should play with track parametrization...
    err.Zero();
    err(0,0) = 0.1;
    err(1,1) = 0.1;
    err(2,2) = 0.1;
    fitter.addMeasParticle( particles[i] = new TFitParticleMCCart( name, name, & mom, dau.mass(), & err ) );
    name[3] ++;
    constraint.addParticle1( particles[i] );
  } 
  fitter.addConstraint(& constraint);
  fitter.setMaxNbIter( 30 );
  fitter.setMaxDeltaS( 1e-2 );
  fitter.setMaxF( 1e-1 );
  fitter.setVerbosity( 0 );                     
  fitter.fit();
  // if (  fitter->getStatus() != 0 ) throw ...
  TLorentzVector sum( 0, 0, 0, 0 );
  for( size_t i = 0; i < daus; ++ i ) {
    Candidate & dau = * c.daughter( i );
    TFitParticleMCCart * part =  particles[i];
    const TLorentzVector * p4 = part->getCurr4Vec();
    dau.setP4( Particle::LorentzVector( p4->X(), p4->Y(), p4->Z(), p4->T() ) );
    sum += * p4;
    delete particles[i];
  }
  c.setP4( Particle::LorentzVector( sum.X(), sum.Y(), sum.Z(), sum.T() ) );
  return FitQuality( fitter.getS(), fitter.getNDF());
}

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Member Data Documentation

double CandMassKinFitter::mass_ [private]

Definition at line 10 of file CandMassKinFitter.h.