1 #ifndef ALI_TPC_CORRECTION_H
2 #define ALI_TPC_CORRECTION_H
4 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
5 * See cxx source for full Copyright notice */
7 ////////////////////////////////////////////////////////////////////////////////
9 // AliTPCCorrection class //
11 // This class provides a general framework to deal with space point //
12 // distortions. An correction class which inherits from here is for example //
13 // AliTPCExBBShape or AliTPCExBTwist //
15 // General functions are (for example): //
16 // CorrectPoint(x,roc) where x is the vector of inital positions in //
17 // cartesian coordinates and roc represents the Read Out chamber number //
18 // according to the offline naming convention. The vector x is overwritten //
19 // with the corrected coordinates. //
21 // An alternative usage would be CorrectPoint(x,roc,dx), which leaves the //
22 // vector x untouched, put returns the distortions via the vector dx //
24 // The class allows "effective Omega Tau" corrections to be shifted to the //
25 // single distortion classes. //
27 // Note: This class is normally used via the class AliTPCComposedCorrection //
29 // date: 27/04/2010 //
30 // Authors: Magnus Mager, Stefan Rossegger, Jim Thomas //
31 ////////////////////////////////////////////////////////////////////////////////
38 class AliTPCCorrection : public TNamed {
40 enum CompositionType {kParallel,kQueue};
43 AliTPCCorrection(const char *name,const char *title);
44 virtual ~AliTPCCorrection();
47 // functions to correct a space point
48 void CorrectPoint ( Float_t x[],const Short_t roc);
49 void CorrectPoint (const Float_t x[],const Short_t roc,Float_t xp[]);
50 virtual void GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]);
52 // functions to distort a space point
53 void DistortPoint ( Float_t x[],const Short_t roc);
54 void DistortPoint (const Float_t x[],const Short_t roc,Float_t xp[]);
55 virtual void GetDistortion(const Float_t x[],const Short_t roc,Float_t dx[]);
60 // convenience functions
61 virtual void Print(Option_t* option="") const;
63 TH2F* CreateHistoDRinXY (Float_t z=10.,Int_t nx=100,Int_t ny=100);
64 TH2F* CreateHistoDRPhiinXY(Float_t z=10.,Int_t nx=100,Int_t nphi=100);
65 TH2F* CreateHistoDRinZR (Float_t phi=0.,Int_t nZ=100,Int_t nR=100);
66 TH2F* CreateHistoDRPhiinZR(Float_t phi=0.,Int_t nZ=100,Int_t nR=100);
68 // normally called directly in the correction classes which inherit from this class
69 virtual void SetOmegaTauT1T2(Float_t omegaTau,Float_t t1,Float_t t2);
72 TH2F* CreateTH2F(const char *name,const char *title,
73 const char *xlabel,const char *ylabel,const char *zlabel,
74 Int_t nbinsx,Double_t xlow,Double_t xup,
75 Int_t nbinsy,Double_t ylow,Double_t yup);
77 static const Double_t fgkTPC_Z0; // nominal gating grid position
78 static const Double_t fgkIFCRadius; // Mean Radius of the Inner Field Cage ( 82.43 min, 83.70 max) (cm)
79 static const Double_t fgkOFCRadius; // Mean Radius of the Outer Field Cage (252.55 min, 256.45 max) (cm)
80 static const Double_t fgkZOffSet; // Offset from CE: calculate all distortions closer to CE as if at this point
81 static const Double_t fgkCathodeV; // Cathode Voltage (volts)
82 static const Double_t fgkGG; // Gating Grid voltage (volts)
84 enum {kNR= 92}; // Number of R points in the table for interpolating distortion data
85 enum {kNZ= 270}; // Number of Z points in the table for interpolating distortion data
86 static const Double_t fgkRList[kNR];
87 static const Double_t fgkZList[kNZ];
89 // Simple Interpolation functions: e.g. with tricubic interpolation (not yet in TH3)
92 void Interpolate2DEdistortion( const Int_t order, const Double_t r, const Double_t z,
93 const Double_t er[kNZ][kNR], Double_t &er_value );
94 Double_t Interpolate( const Double_t xArray[], const Double_t yArray[],
95 const Int_t order, const Double_t x );
96 void Search( const Int_t n, const Double_t xArray[], const Double_t x, Int_t &low );
100 ClassDef(AliTPCCorrection,1);