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46ae650f | 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 | ||
3010c308 | 16 | /* $Id$ */ |
17 | ||
46ae650f | 18 | //----------------------------------------------------------------- |
19 | // Implementation of the derived class for track residuals | |
20 | // based on linear chi2 minimization (in approximation of | |
21 | // small alignment angles and translations) | |
22 | // | |
23 | //----------------------------------------------------------------- | |
24 | ||
3010c308 | 25 | #include <TMath.h> |
46ae650f | 26 | #include <TMinuit.h> |
27 | #include <TGeoMatrix.h> | |
28 | ||
cc345ce3 | 29 | #include "AliLog.h" |
46ae650f | 30 | #include "AliAlignObj.h" |
31 | #include "AliTrackPointArray.h" | |
32 | #include "AliTrackResidualsFast.h" | |
33 | ||
34 | ClassImp(AliTrackResidualsFast) | |
35 | ||
36 | //______________________________________________________________________________ | |
75e3794b | 37 | AliTrackResidualsFast::AliTrackResidualsFast(): |
38 | AliTrackResiduals(), | |
39 | fSumR(0) | |
46ae650f | 40 | { |
41 | // Default constructor | |
cc345ce3 | 42 | for (Int_t i = 0; i < 27; i++) fSum[i] = 0; |
46ae650f | 43 | } |
44 | ||
45 | //______________________________________________________________________________ | |
46 | AliTrackResidualsFast::AliTrackResidualsFast(Int_t ntracks): | |
75e3794b | 47 | AliTrackResiduals(ntracks), |
48 | fSumR(0) | |
46ae650f | 49 | { |
50 | // Constructor | |
cc345ce3 | 51 | for (Int_t i = 0; i < 27; i++) fSum[i] = 0; |
46ae650f | 52 | } |
53 | ||
54 | //______________________________________________________________________________ | |
55 | AliTrackResidualsFast::AliTrackResidualsFast(const AliTrackResidualsFast &res): | |
75e3794b | 56 | AliTrackResiduals(res), |
57 | fSumR(res.fSumR) | |
46ae650f | 58 | { |
59 | // Copy constructor | |
cc345ce3 | 60 | for (Int_t i = 0; i < 27; i++) fSum[i] = res.fSum[i]; |
46ae650f | 61 | } |
62 | ||
63 | //______________________________________________________________________________ | |
64 | AliTrackResidualsFast &AliTrackResidualsFast::operator= (const AliTrackResidualsFast& res) | |
65 | { | |
66 | // Assignment operator | |
67 | ((AliTrackResiduals *)this)->operator=(res); | |
cc345ce3 | 68 | for (Int_t i = 0; i < 27; i++) fSum[i] = res.fSum[i]; |
46ae650f | 69 | fSumR = res.fSumR; |
70 | ||
71 | return *this; | |
72 | } | |
73 | ||
74 | //______________________________________________________________________________ | |
75 | Bool_t AliTrackResidualsFast::Minimize() | |
76 | { | |
77 | // Implementation of fast linear Chi2 | |
78 | // based minimization of track residuals sum | |
cc345ce3 | 79 | for (Int_t i = 0; i < 27; i++) fSum[i] = 0; |
46ae650f | 80 | fSumR = 0; |
81 | ||
82 | AliTrackPoint p1,p2; | |
83 | ||
84 | for (Int_t itrack = 0; itrack < fLast; itrack++) { | |
85 | if (!fVolArray[itrack] || !fTrackArray[itrack]) continue; | |
86 | for (Int_t ipoint = 0; ipoint < fVolArray[itrack]->GetNPoints(); ipoint++) { | |
87 | fVolArray[itrack]->GetPoint(p1,ipoint); | |
88 | fTrackArray[itrack]->GetPoint(p2,ipoint); | |
89 | AddPoints(p1,p2); | |
90 | } | |
91 | } | |
92 | ||
93 | return Update(); | |
94 | ||
95 | // debug info | |
96 | // Float_t chi2 = 0; | |
97 | // for (Int_t itrack = 0; itrack < fLast; itrack++) { | |
98 | // if (!fVolArray[itrack] || !fTrackArray[itrack]) continue; | |
99 | // for (Int_t ipoint = 0; ipoint < fVolArray[itrack]->GetNPoints(); ipoint++) { | |
100 | // fVolArray[itrack]->GetPoint(p1,ipoint); | |
101 | // fAlignObj->Transform(p1); | |
102 | // fTrackArray[itrack]->GetPoint(p2,ipoint); | |
103 | // Float_t residual = p2.GetResidual(p1,kFALSE); | |
104 | // chi2 += residual; | |
105 | // } | |
106 | // } | |
107 | // printf("Final chi2 = %f\n",chi2); | |
108 | } | |
109 | ||
110 | //______________________________________________________________________________ | |
111 | void AliTrackResidualsFast::AddPoints(AliTrackPoint &p, AliTrackPoint &pprime) | |
112 | { | |
113 | // Update the sums used for | |
114 | // the linear chi2 minimization | |
115 | Float_t xyz[3],xyzp[3]; | |
cc345ce3 | 116 | Float_t cov[6],covp[6]; |
117 | p.GetXYZ(xyz,cov); pprime.GetXYZ(xyzp,covp); | |
118 | TMatrixDSym mcov(3); | |
119 | mcov(0,0) = cov[0]; mcov(0,1) = cov[1]; mcov(0,2) = cov[2]; | |
120 | mcov(1,0) = cov[1]; mcov(1,1) = cov[3]; mcov(1,2) = cov[4]; | |
121 | mcov(2,0) = cov[2]; mcov(2,1) = cov[4]; mcov(2,2) = cov[5]; | |
122 | TMatrixDSym mcovp(3); | |
123 | mcovp(0,0) = covp[0]; mcovp(0,1) = covp[1]; mcovp(0,2) = covp[2]; | |
124 | mcovp(1,0) = covp[1]; mcovp(1,1) = covp[3]; mcovp(1,2) = covp[4]; | |
125 | mcovp(2,0) = covp[2]; mcovp(2,1) = covp[4]; mcovp(2,2) = covp[5]; | |
126 | TMatrixDSym msum = mcov + mcovp; | |
127 | msum.Invert(); | |
128 | if (!msum.IsValid()) return; | |
129 | ||
130 | TMatrixD sums(3,1); | |
131 | sums(0,0) = (xyzp[0]-xyz[0]); | |
132 | sums(1,0) = (xyzp[1]-xyz[1]); | |
133 | sums(2,0) = (xyzp[2]-xyz[2]); | |
134 | TMatrixD sumst = sums.T(); sums.T(); | |
135 | ||
136 | TMatrixD mf(3,6); | |
137 | mf(0,0) = 1; mf(1,0) = 0; mf(2,0) = 0; | |
138 | mf(0,1) = 0; mf(1,1) = 1; mf(2,1) = 0; | |
139 | mf(0,2) = 0; mf(1,2) = 0; mf(2,2) = 1; | |
140 | mf(0,3) = 0; mf(1,3) =-xyz[2]; mf(2,3) = xyz[1]; | |
141 | mf(0,4) = xyz[2]; mf(1,4) = 0; mf(2,4) =-xyz[0]; | |
142 | mf(0,5) =-xyz[1]; mf(1,5) = xyz[0]; mf(2,5) = 0; | |
143 | TMatrixD mft = mf.T(); mf.T(); | |
144 | TMatrixD sums2 = mft * msum * sums; | |
145 | ||
146 | TMatrixD smatrix = mft * msum * mf; | |
147 | ||
148 | fSum[0] += smatrix(0,0); | |
149 | fSum[1] += smatrix(0,1); | |
150 | fSum[2] += smatrix(0,2); | |
151 | fSum[3] += smatrix(0,3); | |
152 | fSum[4] += smatrix(0,4); | |
153 | fSum[5] += smatrix(0,5); | |
154 | fSum[6] += smatrix(1,1); | |
155 | fSum[7] += smatrix(1,2); | |
156 | fSum[8] += smatrix(1,3); | |
157 | fSum[9] += smatrix(1,4); | |
158 | fSum[10]+= smatrix(1,5); | |
159 | fSum[11]+= smatrix(2,2); | |
160 | fSum[12]+= smatrix(2,3); | |
161 | fSum[13]+= smatrix(2,4); | |
162 | fSum[14]+= smatrix(2,5); | |
163 | fSum[15]+= smatrix(3,3); | |
164 | fSum[16]+= smatrix(3,4); | |
165 | fSum[17]+= smatrix(3,5); | |
166 | fSum[18]+= smatrix(4,4); | |
167 | fSum[19]+= smatrix(4,5); | |
168 | fSum[20]+= smatrix(5,5); | |
169 | fSum[21] += sums2(0,0); | |
170 | fSum[22] += sums2(1,0); | |
171 | fSum[23] += sums2(2,0); | |
172 | fSum[24] += sums2(3,0); | |
173 | fSum[25] += sums2(4,0); | |
174 | fSum[26] += sums2(5,0); | |
175 | ||
176 | TMatrixD tmp = sumst * msum * sums; | |
177 | fSumR += tmp(0,0); | |
46ae650f | 178 | |
179 | fNdf += 3; | |
180 | } | |
181 | ||
182 | //______________________________________________________________________________ | |
183 | Bool_t AliTrackResidualsFast::Update() | |
184 | { | |
185 | // Find the alignment parameters | |
186 | // by using the already accumulated | |
187 | // sums | |
188 | TMatrixDSym smatrix(6); | |
189 | TMatrixD sums(1,6); | |
190 | ||
3bbfb291 | 191 | smatrix(0,0) = fSum[0]; |
192 | smatrix(0,1) = smatrix(1,0) = fSum[1]; | |
193 | smatrix(0,2) = smatrix(2,0) = fSum[2]; | |
194 | smatrix(0,3) = smatrix(3,0) = fSum[3]; | |
195 | smatrix(0,4) = smatrix(4,0) = fSum[4]; | |
196 | smatrix(0,5) = smatrix(5,0) = fSum[5]; | |
197 | smatrix(1,1) = fSum[6]; | |
198 | smatrix(1,2) = smatrix(2,1) = fSum[7]; | |
199 | smatrix(1,3) = smatrix(3,1) = fSum[8]; | |
200 | smatrix(1,4) = smatrix(4,1) = fSum[9]; | |
201 | smatrix(1,5) = smatrix(5,1) = fSum[10]; | |
202 | smatrix(2,2) = fSum[11]; | |
203 | smatrix(2,3) = smatrix(3,2) = fSum[12]; | |
204 | smatrix(2,4) = smatrix(4,2) = fSum[13]; | |
205 | smatrix(2,5) = smatrix(5,2) = fSum[14]; | |
206 | smatrix(3,3) = fSum[15]; | |
207 | smatrix(3,4) = smatrix(4,3) = fSum[16]; | |
208 | smatrix(3,5) = smatrix(5,3) = fSum[17]; | |
209 | smatrix(4,4) = fSum[18]; | |
210 | smatrix(4,5) = smatrix(5,4) = fSum[19]; | |
cc345ce3 | 211 | smatrix(5,5) = fSum[20]; |
212 | ||
213 | sums(0,0) = fSum[21]; sums(0,1) = fSum[22]; sums(0,2) = fSum[23]; | |
214 | sums(0,3) = fSum[24]; sums(0,4) = fSum[25]; sums(0,5) = fSum[26]; | |
46ae650f | 215 | |
216 | smatrix.Invert(); | |
217 | if (!smatrix.IsValid()) return kFALSE; | |
218 | ||
219 | TMatrixD res = sums*smatrix; | |
220 | fAlignObj->SetPars(res(0,0),res(0,1),res(0,2), | |
221 | TMath::RadToDeg()*res(0,3), | |
222 | TMath::RadToDeg()*res(0,4), | |
223 | TMath::RadToDeg()*res(0,5)); | |
224 | TMatrixD tmp = res*sums.T(); | |
225 | fChi2 = fSumR - tmp(0,0); | |
226 | fNdf -= 6; | |
227 | ||
228 | return kTRUE; | |
229 | } |