STEER/AliTrackResidualsLinear.h

   1 #ifndef ALITRACKRESIDUALSLINEAR_H
   2 #define ALITRACKRESIDUALSLINEAR_H
   3
   4 //************************************************************************
   5 // AliTrackResidualsLinear: derived class (from AliTrackResiduals) which   *
   6 // implements a simple linear minimization of the track residuals chi2.  *
   7 // The minimization relies on the fact that the alignment parameters     *
   8 // (angles and translations) are small.                                  *
   9 //                                                                       *
  10 //                                                                       *
  11 //************************************************************************
  12
  13 #include "AliAlignObj.h"
  14 #include "AliTrackResiduals.h"
  15 class TLinearFitter;
  16
  17 class AliTrackResidualsLinear : public AliTrackResiduals {
  18
  19  public:
  20   AliTrackResidualsLinear();
  21   AliTrackResidualsLinear(Int_t ntracks);
  22   AliTrackResidualsLinear(const AliTrackResidualsLinear &res);
  23   AliTrackResidualsLinear& operator= (const AliTrackResidualsLinear& res);
  24   virtual ~AliTrackResidualsLinear();
  25   Bool_t Minimize();
  26   void   SetRobust(Float_t fraction){fFraction=fraction;}
  27   void   FixParameter(Int_t par, Float_t value) {fBFixed[par]=kTRUE; fFixed[par]= value;}
  28   const Double_t * GetParameters() const { return fParams;}
  29   const Double_t * GetCovariance() const { return fCovar;}
  30   void   ReleaseParameter(Int_t par) {fBFixed[par]=kFALSE;}
  31  protected:
  32   Bool_t Update();
  33   void   AddPoints(AliTrackPoint &p, AliTrackPoint &pprime);
  34   TLinearFitter *fFitter;           // !Linear fitter
  35   Float_t fFraction;                // fraction of points for robust fitter if less 0 - no robust fitter invoked
  36   Double_t fParams[6];               // resulting parameters
  37   Double_t fCovar[36];               // covariance matrix
  38   Float_t fFixed[6];                // the fixed values of parameters
  39   Float_t fBFixed[6];               // the flag for fixing parameter
  40   Double_t fChi2Orig;               // original chi2
  41   ClassDef(AliTrackResidualsLinear,1)
  42
  43 };
  44
  45 #endif