Possibility to define the magnetic field in the reconstruction (Yu.Belikov)

[u/mrichter/AliRoot.git] / STEER / AliTracker.cxx

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 * Author: The ALICE Off-line Project.                                    *
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//-------------------------------------------------------------------------
//               Implementation of the AliTracker class
//
//          Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
//-------------------------------------------------------------------------
#include <TMath.h>

#include "AliTracker.h"
#include "AliCluster.h"
#include "AliKalmanTrack.h"

ClassImp(AliTracker)

//__________________________________________________________________________
void AliTracker::CookLabel(AliKalmanTrack *t, Float_t wrong) const {
  //--------------------------------------------------------------------
  //This function "cooks" a track label. If label<0, this track is fake.
  //--------------------------------------------------------------------
  Int_t noc=t->GetNumberOfClusters();
  Int_t *lb=new Int_t[noc];
  Int_t *mx=new Int_t[noc];
  AliCluster **clusters=new AliCluster*[noc];

  Int_t i;
  for (i=0; i<noc; i++) {
     lb[i]=mx[i]=0;
     Int_t index=t->GetClusterIndex(i);
     clusters[i]=GetCluster(index);
  }

  Int_t lab=123456789;
  for (i=0; i<noc; i++) {
    AliCluster *c=clusters[i];
    lab=TMath::Abs(c->GetLabel(0));
    Int_t j;
    for (j=0; j<noc; j++) if (lb[j]==lab || mx[j]==0) break;
    lb[j]=lab;
    (mx[j])++;
  }

  Int_t max=0;
  for (i=0; i<noc; i++) if (mx[i]>max) {max=mx[i]; lab=lb[i];}
    
  for (i=0; i<noc; i++) {
    AliCluster *c=clusters[i];
    if (TMath::Abs(c->GetLabel(1)) == lab ||
        TMath::Abs(c->GetLabel(2)) == lab ) max++;
  }

  if ((1.- Float_t(max)/noc) > wrong) lab=-lab;
  t->SetLabel(lab);

  delete[] lb;
  delete[] mx;
  delete[] clusters;
}

//____________________________________________________________________________
void AliTracker::UseClusters(const AliKalmanTrack *t, Int_t from) const {
  //------------------------------------------------------------------
  //This function marks clusters associated with the track.
  //------------------------------------------------------------------
  Int_t noc=t->GetNumberOfClusters();
  for (Int_t i=from; i<noc; i++) {
     Int_t index=t->GetClusterIndex(i);
     AliCluster *c=GetCluster(index); 
     c->Use();   
  }
}