Int_t GetSector(Double_t alpha) const;
Int_t GetStack(const AliExternalTrackParam *paramOut) const;
Double_t GetExtZ(const AliExternalTrackParam *paramIn) const;
+ Int_t FillBits(TH1D *hist, Int_t code, Int_t offset);
void BuildRatio(TH1D *ratio, TH1D *histN, TH1D *histD);