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MassKinematicConstraint Class Reference

Mass track constraint class. More...

#include <RecoVertex/KinematicFit/interface/MassKinematicConstraint.h>

Inheritance diagram for MassKinematicConstraint:

KinematicConstraint

List of all members.

Public Member Functions

virtual MassKinematicConstraint * clone () const
 Clone method.
virtual pair< AlgebraicMatrix,
AlgebraicVector > 		derivative (const vector< RefCountedKinematicParticle > par) const
virtual pair< AlgebraicMatrix,
AlgebraicVector > 		derivative (const AlgebraicVector &exPoint) const
virtual AlgebraicVector deviations (int nStates) const
 Returns vector of sigma squared associated to the KinematicParameters of refitted particles Initial deviations are given by user for the constraining parameters (mass, momentum components etc).
 MassKinematicConstraint (const ParticleMass &m, const float sigma)
 Constructor with mass to be used as constraint value.
virtual int numberOfEquations () const
 Returns number of constraint equations used for fitting.
virtual pair< AlgebraicVector,
AlgebraicVector > 		value (const vector< RefCountedKinematicParticle > par) const
 Vector of values and matrix of derivatives calculated using current state parameters as expansion point.
virtual pair< AlgebraicVector,
AlgebraicVector > 		value (const AlgebraicVector &exPoint) const
 Vector of values and matrix of derivatives calculated at given 7xNumberOfStates point.

Private Attributes

AlgebraicVector dd
ParticleMass mass

Detailed Description

Mass track constraint class.

Provides a way to compute derivative matrix and vector of values for mass constraint on the single trajectory. This class does not have the multistate version, since vertex definition needed to calculate a joint mass of several particles.

Kirill Prokofiev December 2002 Multitrack interface: July 2004

Definition at line 17 of file MassKinematicConstraint.h.

Constructor & Destructor Documentation

MassKinematicConstraint::MassKinematicConstraint ( const ParticleMass &  m,
const float  sigma 
)

Constructor with mass to be used as constraint value.

Definition at line 4 of file MassKinematicConstraint.cc.

References dd, and mass.

Referenced by clone().

00005 {
00006  mass = m;
00007  AlgebraicVector deviation_l(7,0);
00008  deviation_l(7) = sigma * sigma; 
00009  dd = deviation_l;
00010 }

Member Function Documentation

virtual MassKinematicConstraint* MassKinematicConstraint::clone (  )  const [inline, virtual]

Clone method.

Implements KinematicConstraint.

Definition at line 53 of file MassKinematicConstraint.h.

References MassKinematicConstraint().

00054  {return new MassKinematicConstraint(*this);}

pair< AlgebraicMatrix, AlgebraicVector > MassKinematicConstraint::derivative ( const vector< RefCountedKinematicParticle >  par  )  const [virtual]

Implements KinematicConstraint.

Definition at line 57 of file MassKinematicConstraint.cc.

00058 {
00059  int nStates = par.size();
00060  if(nStates == 0) throw VertexException("MassKinematicConstraint::empty vector of particles passed");
00061  if(nStates !=1) throw VertexException("MassKinematicConstraint::multiple state refit is not supported in this version");
00062 
00063  AlgebraicVector point = asHepVector<7>(par.front()->currentState().kinematicParameters().vector());
00064  AlgebraicMatrix dr(1,7,0);
00065  dr(1,7) = 1;
00066  return pair<AlgebraicMatrix,AlgebraicVector>(dr,point);
00067 }

pair< AlgebraicMatrix, AlgebraicVector > MassKinematicConstraint::derivative ( const AlgebraicVector &  exPoint  )  const [virtual]

Implements KinematicConstraint.

Definition at line 30 of file MassKinematicConstraint.cc.

00031 {
00032  if(exPoint.num_row() == 0) throw VertexException("MomentumKinematicConstraint::deriavtive requested for zero Linearization point");
00033 
00034 //security check for extended cartesian parametrization 
00035  int inSize = exPoint.num_row(); 
00036  if((inSize%7) !=0) throw VertexException("MomentumKinematicConstraint::linearization point has a wrong dimension");
00037  int nStates = inSize/7;
00038  if(nStates !=1) throw VertexException("MassKinematicConstraint::multiple state refit is not supported in this version");
00039  AlgebraicMatrix dr(1,7,0);
00040  dr(1,7) = 1; 
00041  AlgebraicVector point = exPoint;
00042  return pair<AlgebraicMatrix,AlgebraicVector>(dr,point); 
00043 }

AlgebraicVector MassKinematicConstraint::deviations ( int  nStates  )  const [virtual]

Returns vector of sigma squared associated to the KinematicParameters of refitted particles Initial deviations are given by user for the constraining parameters (mass, momentum components etc).

In case of multiple states exactly the same values are added to every particle parameters

Implements KinematicConstraint.

Definition at line 69 of file MassKinematicConstraint.cc.

References dd, and res.

00070 {
00071  if(nStates == 0) throw VertexException("MassKinematicConstraint::empty vector of particles passed");
00072  if(nStates !=1) throw VertexException("MassKinematicConstraint::multiple state refit is not supported in this version");
00073  AlgebraicVector res = dd;
00074  return res;
00075 }

int MassKinematicConstraint::numberOfEquations (  )  const [virtual]

Returns number of constraint equations used for fitting.

Method is relevant for proper NDF calculations.

Implements KinematicConstraint.

Definition at line 77 of file MassKinematicConstraint.cc.

00078 {return 1;}

pair< AlgebraicVector, AlgebraicVector > MassKinematicConstraint::value ( const vector< RefCountedKinematicParticle >  par  )  const [virtual]

Vector of values and matrix of derivatives calculated using current state parameters as expansion point.

Implements KinematicConstraint.

Definition at line 45 of file MassKinematicConstraint.cc.

References mass.

00046 {
00047  int nStates = par.size();
00048  if(nStates == 0) throw VertexException("MassKinematicConstraint::empty vector of particles passed");
00049  if(nStates !=1) throw VertexException("MassKinematicConstraint::multiple state refit is not supported in this version");
00050  
00051  AlgebraicVector point = asHepVector<7>(par.front()->currentState().kinematicParameters().vector());
00052  AlgebraicVector vl(1,0);
00053  vl(1) = point(7) - mass;
00054  return pair<AlgebraicVector,AlgebraicVector>(vl,point);
00055 }

pair< AlgebraicVector, AlgebraicVector > MassKinematicConstraint::value ( const AlgebraicVector &  exPoint  )  const [virtual]

Vector of values and matrix of derivatives calculated at given 7xNumberOfStates point.

Implements KinematicConstraint.

Definition at line 12 of file MassKinematicConstraint.cc.

References mass.

00013 {
00014 
00015 //we have only one equation and only one track, means the constraint value 
00016 //for track parameters is just a single number
00017  if(exPoint.num_row() ==0 ) throw VertexException("MomentumKinematicConstraint::value requested for zero Linearization point");
00018 
00019 //security check for extended cartesian parametrization 
00020  int inSize = exPoint.num_row(); 
00021  if((inSize%7) !=0) throw VertexException("MomentumKinematicConstraint::linearization point has a wrong dimension");
00022  int nStates = inSize/7;
00023  if(nStates !=1) throw VertexException("MassKinematicConstraint::multiple state refit is not supported in this version");
00024  AlgebraicVector vl(1,0);
00025  AlgebraicVector point = exPoint;
00026  vl(1) = point(7) - mass; 
00027  return pair<AlgebraicVector,AlgebraicVector>(vl,point);
00028 }

Member Data Documentation

AlgebraicVector MassKinematicConstraint::dd [private]

Definition at line 58 of file MassKinematicConstraint.h.

Referenced by deviations(), and MassKinematicConstraint().

ParticleMass MassKinematicConstraint::mass [private]

Definition at line 57 of file MassKinematicConstraint.h.

Referenced by MassKinematicConstraint(), and value().

The documentation for this class was generated from the following files:
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