class AliTRDtrackV1: public AliKalmanTrack

 Default constructor

printf("AliTRDtrackV1::AliTRDtrackV1()\n");

 Copy constructor

 Constructor from AliESDtrack

 The stand alone tracking constructor
 TEMPORARY !!!!!!!!!!!
 to check :
 1. covariance matrix
 2. dQdl calculation

 Clean up all objects allocated by the track during its lifetime.

 Assignment operator

 Copy function

 Set MC label for this track
 On demand i.e. if arrays "labs" and "freq" are allocated by user returns :
   nlabs = the no of distinct labels
   labs  = array of distinct labels in decreasing order of frequency
   freq  = frequency of each label  in decreasing order

 Cook the PID information for the track by delegating the omonim function of the tracklets.
 Computes the number of tracklets used. The tracklet information are considered independent.
 For the moment no global track measurement of PID is performed as for example to estimate
 bremsstrahlung probability based on global chi2 of the track.

 The status bit AliESDtrack::kTRDpid is set during the call of AliTRDtrackV1::UpdateESDtrack().The PID performance of the
TRD for tracks with 6 tacklets is displayed below.

 Retrieve number of tracklets used for PID calculation.

 Get the cluster at a certain position in the track

 Get the cluster index at a certain position in the track

 Compute chi2 between tracklet and track. The value is calculated at the radial position of the track
 equal to the reference radial position of the tracklet (see AliTRDseedV1)

 The chi2 estimator is computed according to the following formula


 where X=(y z), the position of the track/tracklet in the yz plane

 Checks whether two tracks are equal

 Creates a backup track
 TO DO update quality check of the track.

 Find a prolongation at given x
 Return -1 if it does not exist

 Propagates this track to a reference plane defined by "xk" [cm]
 correcting for the mean crossed material.

 "xx0"  - thickness/rad.length [units of the radiation length]
 "xrho" - thickness*density    [g/cm^2]

 Propagate track to the radial position
 Rotation always connected to the last track position

 Print track status

 Rotates track parameters in R*phi plane
 if absolute rotation alpha is in global system
 otherwise alpha rotation is relative to the current rotation angle

 Calculate the number of clusters attached to this track

 Toggle ownership of tracklets

 Set the tracklets

  Save location of birth for the TRD track
  If the pointer is not valid allocate memory

  Save location of death for the TRD track
  If the pointer is not valid allocate memory

 Update chi2/track with one tracklet contribution

 Update the TRD PID information in the ESD track

Origin: Xianguo Lu <xianguo.lu@cern.ch>, Marian Ivanov <marian.ivanov@cern.ch>

 temporary override TObject::Clone to avoid crashes in reco