more secure string operations
[u/mrichter/AliRoot.git] / TPC / AliTPCExBBShape.cxx
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0116859c 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
16////////////////////////////////////////////////////////////////////////////
b4caed64 17// AliTPCExBBShape class //
0116859c 18////////////////////////////////////////////////////////////////////////////
19
20#include <AliMagF.h>
534fd34a 21#include "TGeoGlobalMagField.h"
22#include "AliTPCcalibDB.h"
23#include "AliTPCParam.h"
24#include "AliLog.h"
0116859c 25
26#include "AliTPCExBBShape.h"
27
28AliTPCExBBShape::AliTPCExBBShape()
29 : AliTPCCorrection("exb_bshape","ExB B-shape"),
30 fC1(0.),fC2(0.),
31 fBField(0)
32{
33 //
34 // default constructor
35 //
36}
37
38AliTPCExBBShape::~AliTPCExBBShape() {
39 //
40 // virtual destructor
41 //
42}
43
e527a1b9 44void AliTPCExBBShape::Init() {
45 //
534fd34a 46 // Initialization funtion
e527a1b9 47 //
48
534fd34a 49 AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
50 if (!magF) AliError("Magneticd field - not initialized");
51 Double_t bzField = magF->SolenoidField()/10.; //field in T
52 SetBField(magF);
53 AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
54 if (!param) AliError("Parameters - not initialized");
55 Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
e527a1b9 56 Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
57 Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ;
e527a1b9 58 // Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a 59 SetOmegaTauT1T2(wt,fT1,fT2);
e527a1b9 60
61
62}
63
64void AliTPCExBBShape::Update(const TTimeStamp &/*timeStamp*/) {
65 //
66 // Update function
67 //
534fd34a 68 AliMagF* magF= (AliMagF*)TGeoGlobalMagField::Instance()->GetField();
69 if (!magF) AliError("Magneticd field - not initialized");
70 Double_t bzField = magF->SolenoidField()/10.; //field in T
71 SetBField(magF);
72 AliTPCParam *param= AliTPCcalibDB::Instance()->GetParameters();
73 if (!param) AliError("Parameters - not initialized");
74 Double_t vdrift = param->GetDriftV()/1000000.; // [cm/us] // From dataBase: to be updated: per second (ideally)
e527a1b9 75 Double_t ezField = 400; // [V/cm] // to be updated: never (hopefully)
76 Double_t wt = -10.0 * (bzField*10) * vdrift / ezField ;
e527a1b9 77 // Correction Terms for effective omegaTau; obtained by a laser calibration run
534fd34a 78 SetOmegaTauT1T2(wt,fT1,fT2);
e527a1b9 79
80
81}
82
83
84
0116859c 85void AliTPCExBBShape::GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]) {
86 //
87 // Calculates the space point corrections of the B field inperfections (B field shape)
88 //
89
90 if (!fBField) {
91 for (Int_t j=0;j<3;++j) dx[j]=0.;
92 return;
93 }
94
95 const Double_t xStart[3]={ x[0], x[1], x[2] };
b1f0a2a5 96 const Double_t xEnd[3]={ x[0], x[1], roc%36<18?fgkTPCZ0:-fgkTPCZ0 };
0116859c 97
98 Double_t intBStart[3];
99 Double_t intBEnd[3];
100
101 fBField->GetTPCRatInt(xStart,intBStart);
102 fBField->GetTPCRatInt(xEnd, intBEnd );
103
104 const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
105 const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
106
107 dx[0]=fC2*intBxOverBz-fC1*intByOverBz;
108 dx[1]=fC1*intBxOverBz+fC2*intByOverBz;
109 dx[2]=0.;
110
111
112}
113
114void AliTPCExBBShape::GetBxAndByOverBz(const Float_t x[],const Short_t roc,Float_t BxByOverBz[]) {
115 //
116 // This function is purely for calibration purposes
117 // Returns the via AliMagF obtaind B field integrals
118 //
119
120 if (!fBField) {
121 for (Int_t j=0;j<3;++j) BxByOverBz[j]=0.;
122 return;
123 }
124
125 const Double_t xStart[3]={ x[0], x[1], x[2] };
b1f0a2a5 126 const Double_t xEnd[3]={ x[0], x[1], roc%36<18?fgkTPCZ0:-fgkTPCZ0 };
0116859c 127
128 Double_t intBStart[3];
129 Double_t intBEnd[3];
130
131 fBField->GetTPCRatInt(xStart,intBStart);
132 fBField->GetTPCRatInt(xEnd, intBEnd );
133
134 const Float_t intBxOverBz=(intBEnd[0]-intBStart[0]);
135 const Float_t intByOverBz=(intBEnd[1]-intBStart[1]);
136
137 BxByOverBz[0]=intBxOverBz;
138 BxByOverBz[1]=intByOverBz;
139
140}
141
142void AliTPCExBBShape::Print(Option_t* option) const {
143 //
144 // Print function to check the settings (e.g. voltage offsets)
145 // option=="a" prints details of the B field settings and the
146 // C0 and C1 coefficents (for calibration purposes)
147 //
148 TString opt = option; opt.ToLower();
534fd34a 149 printf("%s\t%s\n - B field settings:\n",GetTitle(),GetName());
0116859c 150 fBField->Print(option);
151 // printf(" - B field: X-Twist: %1.5lf rad, Y-Twist: %1.5lf rad \n",fBField->Print(option));
534fd34a 152 if (opt.Contains("a")) { // Print all details
153 printf(" - T1: %1.4f, T2: %1.4f \n",fT1,fT2);
0116859c 154 printf(" - C1: %1.4f, C2: %1.4f \n",fC1,fC2);
155 }
0116859c 156}