GFAbsTrackRep Class Reference

Base Class for genfit track representations. Defines interface for track parameterizations. More...

#include <GFAbsTrackRep.h>

Inheritance diagram for GFAbsTrackRep:

Public Member Functions
virtual GFAbsTrackRep *	clone () const =0
virtual GFAbsTrackRep *	prototype () const =0
virtual double	extrapolate (const GFDetPlane &plane, TMatrixT< double > &statePred)
	returns the tracklength spanned in this extrapolation More...
	GFAbsTrackRep ()
	GFAbsTrackRep (int)
virtual	~GFAbsTrackRep ()
virtual void	extrapolateToPoint (const TVector3 &point, TVector3 &poca, TVector3 &normVec)
	This method is to extrapolate the track to point of closest approach to a point in space. More...
virtual void	extrapolateToLine (const TVector3 &point1, const TVector3 &point2, TVector3 &poca, TVector3 &normVec, TVector3 &poca_onwire)
	This method extrapolates to the point of closest approach to a line. More...
virtual double	stepalong (double h, TVector3 &point, TVector3 &dir)
	make step of h cm along the track More...
virtual double	extrapolate (const GFDetPlane &plane, TMatrixT< double > &statePred, TMatrixT< double > &covPred)=0
	Extrapolates the track to the given detectorplane. More...
double	extrapolate (const GFDetPlane &plane)
	This changes the state and cov and plane of the rep. More...
unsigned int	getDim () const
	returns dimension of state vector More...
virtual void	Print () const
TMatrixT< double >	getState () const
TMatrixT< double >	getCov () const
double	getStateElem (int i) const
double	getCovElem (int i, int j) const
virtual TVector3	getPos (const GFDetPlane &pl)=0
virtual TVector3	getMom (const GFDetPlane &pl)=0
virtual void	getPosMom (const GFDetPlane &pl, TVector3 &pos, TVector3 &mom)=0
virtual void	getPosMomCov (const GFDetPlane &pl, TVector3 &pos, TVector3 &mom, TMatrixT< double > &cov)
	method which gets position, momentum and 6x6 covariance matrix More...
virtual double	getCharge () const =0
TVector3	getPos ()
TVector3	getMom ()
void	getPosMomCov (TVector3 &pos, TVector3 &mom, TMatrixT< double > &c)
TMatrixT< double >	getFirstState () const
TMatrixT< double >	getFirstCov () const
GFDetPlane	getFirstPlane () const
TMatrixT< double >	getLastState () const
TMatrixT< double >	getLastCov () const
GFDetPlane	getLastPlane () const
double	getChiSqu () const
double	getRedChiSqu () const
	returns chi2/ndf More...
unsigned int	getNDF () const
virtual void	setData (const TMatrixT< double > &st, const GFDetPlane &pl, const TMatrixT< double > *cov=nullptr, const TMatrixT< double > *aux=nullptr)
	Puts the track representation in a given state. More...
void	setCov (const TMatrixT< double > &aCov)
void	setFirstState (const TMatrixT< double > &aState)
void	setFirstCov (const TMatrixT< double > &aCov)
void	setFirstPlane (const GFDetPlane &aPlane)
void	setLastState (const TMatrixT< double > &aState)
void	setLastCov (const TMatrixT< double > &aCov)
void	setLastPlane (const GFDetPlane &aPlane)
const GFDetPlane &	getReferencePlane () const
void	setChiSqu (double aChiSqu)
void	setNDF (unsigned int n)
void	addChiSqu (double aChiSqu)
void	addNDF (unsigned int n)
void	setStatusFlag (int _val)
virtual void	switchDirection ()=0
bool	setInverted (bool f=true)
	Deprecated. Should be removed soon. More...
bool	getStatusFlag ()
virtual void	reset ()
virtual bool	hasAuxInfo ()
	See if the track representation has auxillary information stored. More...
virtual const TMatrixT< double > *	getAuxInfo (const GFDetPlane &)
	Get auxillary information from the track representation. More...

Protected Attributes
unsigned int	fDimension
	Dimensionality of track representation. More...
TMatrixT< double >	fState
	The vector of track parameters. More...
TMatrixT< double >	fCov
	The covariance matrix. More...
double	fChiSqu
	chiSqu of the track fit More...
unsigned int	fNdf
int	fStatusFlag
	status of track representation: 0 means everything's OK More...
bool	fInverted
	specifies the direction of flight of the particle More...
TMatrixT< double >	fFirstState
	state, cov and plane for first and last point in fit More...
TMatrixT< double >	fFirstCov
TMatrixT< double >	fLastState
TMatrixT< double >	fLastCov
GFDetPlane	fFirstPlane
GFDetPlane	fLastPlane
GFDetPlane	fRefPlane

Detailed Description

Base Class for genfit track representations. Defines interface for track parameterizations.

Author

Christian Höppner (Technische Universität München, original author)

Sebastian Neubert (Technische Universität München, original author)

It is important to understand the difference between a track and a track representation in genfit:

• A track representation is a specific parameterization of a trajectory. It contains the parameters that describe the track at some point and code for the extrapolation of the track parameters through space. The actual extrapolation code is not part of genfit but has to be supplied in some additional package (e.g. GEANE). LSLTrackRep is a very basic example of a track representation.
• A Track is a collection of RecoHits (see GFAbsRecoHit) plus a collection of track representation objects. The hits can be from different detectors. There can be several representations of the same track. This makes it possible to perform several fits in parallel, for example to compare different parameterizations or to fit different particle hypotheses.

All track tepresentations must inherit GFAbsTrackRep to be available in genfit. Algorithms in genfit use this class as interface to access track parameters

Provides:

• Matrix objects to store track parameters
• ... and covariances
• interface to track extrapolation code

The track extrapolation engine can be exchanged in genfit. Or one can even use more than one engine in parallel! In order to use a track extrapolation engine (like e.g. GEANE) with genfit one has to write a TrackRep class that inherits from GFAbsTrackRep. This makes it possible to uses different track extrapolation codes within a unified framework without major changes in the detector code.

There is only one thing one has to do to use a specific track representation together with the hits from a detector: add the respective code in the GFAbsRecoHit::getHMatrix method implementation of the RecoHit in question.

Definition at line 80 of file GFAbsTrackRep.h.

Constructor & Destructor Documentation

GFAbsTrackRep() [1/2]

GFAbsTrackRep::GFAbsTrackRep

(

)

GFAbsTrackRep() [2/2]

GFAbsTrackRep::GFAbsTrackRep

(

int

)

~GFAbsTrackRep()

virtual GFAbsTrackRep::~GFAbsTrackRep ( )

virtual

Member Function Documentation

addChiSqu()

void GFAbsTrackRep::addChiSqu ( double  aChiSqu )

inline

Definition at line 263 of file GFAbsTrackRep.h.

{ fChiSqu += aChiSqu; }

addNDF()

void GFAbsTrackRep::addNDF ( unsigned int  n )

inline

Definition at line 264 of file GFAbsTrackRep.h.

{ fNdf += n; }

clone()

virtual GFAbsTrackRep* GFAbsTrackRep::clone ( ) const

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

extrapolate() [1/3]

virtual double GFAbsTrackRep::extrapolate ( const GFDetPlane &  plane, TMatrixT< double > &  statePred  )

virtual

returns the tracklength spanned in this extrapolation

There is a default implementation in GFAbsTrackRep.cxx which just drops the predicted covaraiance. If your trackrep has a way to extrapolate without giving a correct cov (that would be faster probably), please overwrite it.

Reimplemented in RKTrackRep, and GeaneTrackRep.

extrapolate() [2/3]

virtual double GFAbsTrackRep::extrapolate ( const GFDetPlane &  plane, TMatrixT< double > &  statePred, TMatrixT< double > &  covPred  )

pure virtual

Extrapolates the track to the given detectorplane.

Results are put into statePred and covPred This method does NOT alter the state of the object!

Implemented in RKTrackRep, and GeaneTrackRep.

extrapolate() [3/3]

double GFAbsTrackRep::extrapolate

(

const GFDetPlane &

plane

)

This changes the state and cov and plane of the rep.

This method extrapolates to to the plane and sets the results of state, cov and also plane in itself.

extrapolateToLine()

virtual void GFAbsTrackRep::extrapolateToLine ( const TVector3 &  point1, const TVector3 &  point2, TVector3 &  poca, TVector3 &  normVec, TVector3 &  poca_onwire  )

virtual

This method extrapolates to the point of closest approach to a line.

This method extrapolates to the POCA to a line, i.e. a wire. There is a default implementation just like for the extrapolateToPoca for trackReps which do not need this feature, which will abort the execution if it is ever called.

Reimplemented in RKTrackRep, and GeaneTrackRep.

extrapolateToPoint()

virtual void GFAbsTrackRep::extrapolateToPoint ( const TVector3 &  point, TVector3 &  poca, TVector3 &  normVec  )

virtual

This method is to extrapolate the track to point of closest approach to a point in space.

There is an empty implementation of this method in GFAbsTrackRep.cxx, which will just abort with an error message. One can overwrite this method if one wishes to implement a track representation, which should have this feature. An example of an experiment in which you would not need this feature would be track fitting (not so much vertexing) in an experiment with only planar trackers like silicons or planar wire chambers and such. An example where you would need it, would be a TPC where you have to fit the track to space points, or other drift chambers with complicated hit topology.

Reimplemented in RKTrackRep, and GeaneTrackRep.

getAuxInfo()

virtual const TMatrixT<double>* GFAbsTrackRep::getAuxInfo ( const GFDetPlane &  )

inlinevirtual

Get auxillary information from the track representation.

AuxInfo is a mechanism which allows creators of track repersentations to hand out any information they like (as long as it is compatible with a TMatrixT<double>). It should be used if setData requires additional information to update the representation, but it can also be used for debugging information if needed. See also the documentation of GFAbsTrackRep::setData().

Reimplemented in RKTrackRep.

Definition at line 296 of file GFAbsTrackRep.h.

  { //(const GFDetPlane& pl)
    return nullptr;
  }

getCharge()

virtual double GFAbsTrackRep::getCharge ( ) const

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

Referenced by GFTrack::getCharge(), and getCovElem().

getChiSqu()

double GFAbsTrackRep::getChiSqu ( ) const

inline

Definition at line 208 of file GFAbsTrackRep.h.

References fChiSqu.

Referenced by GFTrack::getChiSqu(), and getRedChiSqu().

{ return fChiSqu; }

getCov()

TMatrixT<double> GFAbsTrackRep::getCov ( ) const

inline

Definition at line 180 of file GFAbsTrackRep.h.

References fCov.

{ return fCov; }

getCovElem()

double GFAbsTrackRep::getCovElem ( int  i, int  j  ) const

inline

Definition at line 183 of file GFAbsTrackRep.h.

References fCov, getCharge(), getMom(), getPos(), getPosMom(), and getPosMomCov().

{ return fCov(i, j); }

getDim()

unsigned int GFAbsTrackRep::getDim ( ) const

inline

returns dimension of state vector

Definition at line 175 of file GFAbsTrackRep.h.

References fDimension, and Print().

Referenced by getNDF().

{ return fDimension; }

getFirstCov()

TMatrixT<double> GFAbsTrackRep::getFirstCov ( ) const

inline

Definition at line 203 of file GFAbsTrackRep.h.

References fFirstCov.

{ return fFirstCov; }

getFirstPlane()

GFDetPlane GFAbsTrackRep::getFirstPlane ( ) const

inline

Definition at line 204 of file GFAbsTrackRep.h.

References fFirstPlane.

{ return fFirstPlane; }

getFirstState()

TMatrixT<double> GFAbsTrackRep::getFirstState ( ) const

inline

Definition at line 202 of file GFAbsTrackRep.h.

References fFirstState.

{ return fFirstState; }

getLastCov()

TMatrixT<double> GFAbsTrackRep::getLastCov ( ) const

inline

Definition at line 206 of file GFAbsTrackRep.h.

References fLastCov.

{ return fLastCov; }

getLastPlane()

GFDetPlane GFAbsTrackRep::getLastPlane ( ) const

inline

Definition at line 207 of file GFAbsTrackRep.h.

References fLastPlane.

{ return fLastPlane; }

getLastState()

TMatrixT<double> GFAbsTrackRep::getLastState ( ) const

inline

Definition at line 205 of file GFAbsTrackRep.h.

References fLastState.

{ return fLastState; }

getMom() [1/2]

virtual TVector3 GFAbsTrackRep::getMom ( const GFDetPlane &  pl )

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

Referenced by GFTrack::getMom().

getMom() [2/2]

TVector3 GFAbsTrackRep::getMom ( )

inline

Definition at line 199 of file GFAbsTrackRep.h.

References getMom().

Referenced by getCovElem(), getMom(), GeaneTrackRep::prototype(), and RKTrackRep::prototype().

{ return getMom(fRefPlane); }

getNDF()

unsigned int GFAbsTrackRep::getNDF ( ) const

inline

Definition at line 216 of file GFAbsTrackRep.h.

References getDim().

Referenced by GFTrack::getNDF(), and getRedChiSqu().

  {
    if (fNdf > getDim())
      return fNdf - getDim();
    return 0;
  }

getPos() [1/2]

virtual TVector3 GFAbsTrackRep::getPos ( const GFDetPlane &  pl )

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

Referenced by GFTrack::getPos().

getPos() [2/2]

TVector3 GFAbsTrackRep::getPos ( )

inline

Definition at line 198 of file GFAbsTrackRep.h.

References getPos().

Referenced by getCovElem(), getPos(), GeaneTrackRep::prototype(), and RKTrackRep::prototype().

{ return getPos(fRefPlane); }

getPosMom()

virtual void GFAbsTrackRep::getPosMom ( const GFDetPlane &  pl, TVector3 &  pos, TVector3 &  mom  )

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

Referenced by getCovElem().

getPosMomCov() [1/2]

virtual void GFAbsTrackRep::getPosMomCov ( const GFDetPlane &  pl, TVector3 &  pos, TVector3 &  mom, TMatrixT< double > &  cov  )

virtual

method which gets position, momentum and 6x6 covariance matrix

default implementation in cxx file, if a ConcreteTrackRep can not implement this functionality

Reimplemented in RKTrackRep, and GeaneTrackRep.

Referenced by getCovElem(), and GFTrack::getPosMomCov().

getPosMomCov() [2/2]

void GFAbsTrackRep::getPosMomCov ( TVector3 &  pos, TVector3 &  mom, TMatrixT< double > &  c  )

inline

Definition at line 200 of file GFAbsTrackRep.h.

References getPosMomCov().

Referenced by getPosMomCov().

{ getPosMomCov(fRefPlane, pos, mom, c); }

getRedChiSqu()

double GFAbsTrackRep::getRedChiSqu ( ) const

inline

returns chi2/ndf

Definition at line 210 of file GFAbsTrackRep.h.

References getChiSqu(), and getNDF().

Referenced by GFTrack::getRedChiSqu().

  {
    if (getNDF() > 0)
      return getChiSqu() / getNDF();
    return 0;
  }

getReferencePlane()

const GFDetPlane& GFAbsTrackRep::getReferencePlane ( ) const

inline

Definition at line 259 of file GFAbsTrackRep.h.

References fRefPlane.

{ return fRefPlane; }

getState()

TMatrixT<double> GFAbsTrackRep::getState ( ) const

inline

Definition at line 179 of file GFAbsTrackRep.h.

References fState.

{ return fState; }

getStateElem()

double GFAbsTrackRep::getStateElem ( int  i ) const

inline

Definition at line 182 of file GFAbsTrackRep.h.

References fState.

{ return fState(i, 0); }

getStatusFlag()

bool GFAbsTrackRep::getStatusFlag ( )

inline

Definition at line 276 of file GFAbsTrackRep.h.

References fStatusFlag, and reset().

{ return fStatusFlag; }

hasAuxInfo()

virtual bool GFAbsTrackRep::hasAuxInfo ( )

inlinevirtual

See if the track representation has auxillary information stored.

See if auxillary information is stored in the track representation. See the documentation of GFAbsTrackRep::getAuxInfo() for details.

Reimplemented in RKTrackRep.

Definition at line 285 of file GFAbsTrackRep.h.

{ return false; }

Print()

virtual void GFAbsTrackRep::Print ( ) const

virtual

Referenced by getDim().

prototype()

virtual GFAbsTrackRep* GFAbsTrackRep::prototype ( ) const

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

reset()

virtual void GFAbsTrackRep::reset ( )

virtual

Referenced by getStatusFlag().

setChiSqu()

void GFAbsTrackRep::setChiSqu ( double  aChiSqu )

inline

Definition at line 261 of file GFAbsTrackRep.h.

{ fChiSqu = aChiSqu; }

setCov()

void GFAbsTrackRep::setCov ( const TMatrixT< double > &  aCov )

inline

Definition at line 243 of file GFAbsTrackRep.h.

{ fCov = aCov; }

setData()

virtual void GFAbsTrackRep::setData ( const TMatrixT< double > &  st, const GFDetPlane &  pl, const TMatrixT< double > *  cov = nullptr, const TMatrixT< double > *  aux = nullptr  )

inlinevirtual

Puts the track representation in a given state.

This is used to update the track representation after the update of the Kalman filter was calculated.

IMPORTANT: One should be able to set the track representation to arbitraty values using this method. If the track representation needs additional information beside the state vector, the plane and the covariance, it has to be handed over via the "aux" Matrix. GFAbsTrackRep::getAuxInfo() should return the appropriate information. This is mandatory if smoothing is used.

Reimplemented in RKTrackRep.

Definition at line 233 of file GFAbsTrackRep.h.

  {
    fState = st;
    fRefPlane = pl;
    if (cov != nullptr)
      fCov = *cov;
    if (aux != nullptr) {
      ;
    }
  }

setFirstCov()

void GFAbsTrackRep::setFirstCov ( const TMatrixT< double > &  aCov )

inline

Definition at line 245 of file GFAbsTrackRep.h.

{ fFirstCov = aCov; }

setFirstPlane()

void GFAbsTrackRep::setFirstPlane ( const GFDetPlane &  aPlane )

inline

Definition at line 246 of file GFAbsTrackRep.h.

  {
    fFirstPlane = aPlane;
    ;
  }

setFirstState()

void GFAbsTrackRep::setFirstState ( const TMatrixT< double > &  aState )

inline

Definition at line 244 of file GFAbsTrackRep.h.

{ fFirstState = aState; }

setInverted()

bool GFAbsTrackRep::setInverted ( bool  f = true )

inline

Deprecated. Should be removed soon.

Definition at line 270 of file GFAbsTrackRep.h.

References f.

  {
    fInverted = f;
    return true;
  }

setLastCov()

void GFAbsTrackRep::setLastCov ( const TMatrixT< double > &  aCov )

inline

Definition at line 252 of file GFAbsTrackRep.h.

{ fLastCov = aCov; }

setLastPlane()

void GFAbsTrackRep::setLastPlane ( const GFDetPlane &  aPlane )

inline

Definition at line 253 of file GFAbsTrackRep.h.

  {
    fLastPlane = aPlane;
    ;
  }

setLastState()

void GFAbsTrackRep::setLastState ( const TMatrixT< double > &  aState )

inline

Definition at line 251 of file GFAbsTrackRep.h.

{ fLastState = aState; }

setNDF()

void GFAbsTrackRep::setNDF ( unsigned int  n )

inline

Definition at line 262 of file GFAbsTrackRep.h.

{ fNdf = n; }

setStatusFlag()

void GFAbsTrackRep::setStatusFlag ( int  _val )

inline

Definition at line 265 of file GFAbsTrackRep.h.

References switchDirection().

{ fStatusFlag = _val; }

stepalong()

virtual double GFAbsTrackRep::stepalong ( double  h, TVector3 &  point, TVector3 &  dir  )

virtual

make step of h cm along the track

There is an emply implementation in GFAbsTrackRep.cxx which will abort (see one of the extrapolate methods above). This can be overwritten, if this feature is needed.

Reimplemented in RKTrackRep.

switchDirection()

virtual void GFAbsTrackRep::switchDirection ( )

pure virtual

Implemented in RKTrackRep, and GeaneTrackRep.

Referenced by setStatusFlag().

Member Data Documentation

fChiSqu

double GFAbsTrackRep::fChiSqu

protected

chiSqu of the track fit

Definition at line 94 of file GFAbsTrackRep.h.

Referenced by getChiSqu().

fCov

TMatrixT<double> GFAbsTrackRep::fCov

protected

The covariance matrix.

Definition at line 91 of file GFAbsTrackRep.h.

Referenced by getCov(), and getCovElem().

fDimension

unsigned int GFAbsTrackRep::fDimension

protected

Dimensionality of track representation.

Definition at line 85 of file GFAbsTrackRep.h.

Referenced by getDim().

fFirstCov

TMatrixT<double> GFAbsTrackRep::fFirstCov

protected

Definition at line 104 of file GFAbsTrackRep.h.

Referenced by getFirstCov().

fFirstPlane

GFDetPlane GFAbsTrackRep::fFirstPlane

protected

Definition at line 108 of file GFAbsTrackRep.h.

Referenced by getFirstPlane().

fFirstState

TMatrixT<double> GFAbsTrackRep::fFirstState

protected

state, cov and plane for first and last point in fit

Definition at line 103 of file GFAbsTrackRep.h.

Referenced by getFirstState().

fInverted

bool GFAbsTrackRep::fInverted

protected

specifies the direction of flight of the particle

Definition at line 100 of file GFAbsTrackRep.h.

fLastCov

TMatrixT<double> GFAbsTrackRep::fLastCov

protected

Definition at line 107 of file GFAbsTrackRep.h.

Referenced by getLastCov().

fLastPlane

GFDetPlane GFAbsTrackRep::fLastPlane

protected

Definition at line 109 of file GFAbsTrackRep.h.

Referenced by getLastPlane().

fLastState

TMatrixT<double> GFAbsTrackRep::fLastState

protected

Definition at line 106 of file GFAbsTrackRep.h.

Referenced by getLastState().

fNdf

unsigned int GFAbsTrackRep::fNdf

protected

Definition at line 95 of file GFAbsTrackRep.h.

fRefPlane

GFDetPlane GFAbsTrackRep::fRefPlane

protected

Definition at line 112 of file GFAbsTrackRep.h.

Referenced by getReferencePlane().

fState

TMatrixT<double> GFAbsTrackRep::fState

protected

The vector of track parameters.

Definition at line 88 of file GFAbsTrackRep.h.

Referenced by GeaneTrackRep::getCharge(), getState(), and getStateElem().

fStatusFlag

int GFAbsTrackRep::fStatusFlag

protected

status of track representation: 0 means everything's OK

Definition at line 98 of file GFAbsTrackRep.h.

Referenced by getStatusFlag().

---

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

• GFAbsTrackRep.h