marlintpc::TrackFitterSimpleChiSquareProcessor Class Reference

A processor which instantiates a TrackFitterSimpleChiSquare and fits the tracks with it. More...

#include <TrackFitterSimpleChiSquareProcessor.h>

Inheritance diagram for marlintpc::TrackFitterSimpleChiSquareProcessor:

Public Member Functions
	TrackFitterSimpleChiSquareProcessor ()
	Default constructor.
	~TrackFitterSimpleChiSquareProcessor ()
	Destructor.
Processor *	newProcessor ()
	Return a new instance of this processor.
void	init ()
	In this processor the init function set the collection parameters for the track collection and instantiates the TrackFitterFactory.
void	processRunHeader (lcio::LCRunHeader *run)
	Called once per run to process the event's header.
virtual void	processEvent (lcio::LCEvent *evt)
	Process event requests a track fitter from the TrackFitterFactory for each event (to update possible conditions data). More...
virtual void	check (lcio::LCEvent *evt)
	Called for every event - right after processEvent() has been called for all processors.
virtual void	end ()
	Called after data processing for clean up in the inverse order of the init() method so that resources allocated in the first processor also will be available for all following processors.

Protected Attributes
std::string	_input_seed_tracks_collection_name
	The name of the input collection of seed tracks.
std::string	_output_tracks_collection_name
	The name of the output collection with the fitted tracks.
int	_outputIsTransient
	Give the status which is set to the transient flag of the output collection. More...
EVENT::LCParameters *	_trackCollectionParameters
float	_transDefocussing
float	_longDefocussing
float	_transDiffusionCoef
float	_longDiffusionCoef
float	_d0Start
	the optional start parameters
float	_phiStart
float	_omegaStart
float	_tanLambdaStart
float	_z0Start
bool	_fixD0
	the flags which fit parameters to fix
bool	_fixPhi
bool	_fixOmega
bool	_fixTanLambda
bool	_fixZ0
bool	_noZFit
	flag whether to fit in z or only xy
int	_nGoodFits
int	_nBadFits

Detailed Description

A processor which instantiates a TrackFitterSimpleChiSquare and fits the tracks with it.

Author

M. Killenberg(University of Bonn)

Input - Prerequisites

• A collection of track candidates (lcio::Tracks) containing the TrackerHits.
  Note: The LCIO::TRBIT_HITS flag has to be set when this collection is created so the hits are stored in the track.

Output

• Collection of fitted tracks.

Parameters

InputTrackCandidates	The the name of the input collection of track candidates (default: TPCTrackCandidates)
OutputTracks	The name of the collection the straight tracks be stored under (default: TPCTracks)
SetOutputTransient	If not 0 the output collection is set transient (default: 0)
TransDefocussing	The transverse defocussing in the readout structure (in mm) (default: 1)
LongDefocussing	The longitudinal defocussing in the readout structure (in mm) (default: 1)
TransDiffusionCoef	The transverse diffusion coefficient (in mm/ ) (default: 0)
TransDefocussing	The longitudinal diffusion coefficient (in mm/ ) (default: 0)

The parameters for the starting values of the fit are optional parameter. If the parameter is given, it is use. If the parameter is not given the value from the seed track is used.

Parameters

D0Start	optional Use this start value for D0 instead of the value from the seed track
TanLambdaStart	optional Use this start value for TanLambda instead of the value from the seed track
Z0Start	optional Use this start value for Z0 instead of the value from the seed track
OmegaStart	optional Use this start value for Omega instead of the value from the seed track
PhiStart	optional Use this start value for Phi instead of the value from the seed track

The following parameters allow to fix a track parameter during the fit. To fit a straight line for instance set OmegaStart to 0. and FixOmega to true.

Parameters

FixD0	Do not vary d0 when fitting (default: false)
FixPhi	Do not vary phi when fitting (default: false)
FixOmega	Do not vary omega when fitting (default: false)
FixTanLambda	Do not vary tanLambda when fitting (default: false)
FixZ0	Do not vary z0 when fitting (default: false)

If you just want to fit in the transverse direction set NoZFit to true. The residuals function will not include the residuals in z.

Parameters

NoZFit

Do not fit in z direction, only use residuals in x-y / r-phi (default: false)

Member Function Documentation

void marlintpc::TrackFitterSimpleChiSquareProcessor::processEvent ( lcio::LCEvent *  evt )

virtual

Process event requests a track fitter from the TrackFitterFactory for each event (to update possible conditions data).

Afterwards it loops all tracks and fits them.

References _d0Start, _fixD0, _input_seed_tracks_collection_name, _noZFit, _output_tracks_collection_name, marlintpc::TrackFitterBase::FITFAILEDBIT, marlintpc::TrackFitterBase::fitTrack(), marlintpc::TrackFitterBase::fixD0(), marlintpc::TrackFitterBase::fixOmega(), marlintpc::TrackFitterBase::fixPhi(), marlintpc::TrackFitterBase::fixTanLambda(), marlintpc::TrackFitterBase::fixZ0(), marlintpc::TrackFitterBase::getFitterType(), marlintpc::TrackFitterFactory::getTrackFitter(), marlintpc::TrackFitterBase::setD0Start(), marlintpc::TrackFitterBase::setNoZFitFlag(), marlintpc::TrackFitterBase::setOmegaStart(), marlintpc::TrackFitterBase::setPhiStart(), marlintpc::TrackFitterBase::setTanLambdaStart(), marlintpc::TrackFitterBase::setZ0Start(), and marlintpc::TrackFitterBase::FitterTypes::SIMPLECHISQUARE.

Member Data Documentation

int marlintpc::TrackFitterSimpleChiSquareProcessor::_outputIsTransient

protected

Give the status which is set to the transient flag of the output collection.

It is an int instead of a boolean, because the processor parameter cannot be a boolean. Hits and tracks can be set separately.

Referenced by TrackFitterSimpleChiSquareProcessor().

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

• TrackFitterSimpleChiSquareProcessor.h
• TrackFitterSimpleChiSquareProcessor.cc