]>
Commit | Line | Data |
---|---|---|
1627d1c4 | 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 | ||
17 | #include "AliTPCpolyTrack.h" | |
18 | #include "TMath.h" | |
19 | ||
20 | ClassImp(AliTPCpolyTrack) | |
21 | ||
22 | ||
23 | AliTPCpolyTrack::AliTPCpolyTrack() | |
24 | { | |
25 | Reset(); | |
26 | } | |
27 | ||
28 | void AliTPCpolyTrack::Reset() | |
29 | { | |
30 | // | |
31 | // reset track | |
32 | fSumX = fSumX2= fSumX3=fSumX4 = fSumY=fSumYX=fSumYX2=fSumZ=fSumZX=fSumZX2=fSumW =0; | |
33 | fNPoints = 0; | |
34 | } | |
35 | ||
36 | void AliTPCpolyTrack::AddPoint(Double_t x, Double_t y, Double_t z,Double_t sy, Double_t sz) | |
37 | { | |
38 | // | |
39 | // | |
40 | if (fNPoints==0){ | |
41 | fMaxX = x; | |
42 | fMinX = x; | |
43 | }else{ | |
44 | if (x>fMaxX) fMaxX=x; | |
45 | if (x<fMinX) fMinX=x; | |
46 | } | |
47 | ||
48 | Double_t x2 = x*x; | |
49 | Double_t w = 2./(sy+sz); | |
50 | fSumW += w; | |
51 | // | |
52 | fSumX += x*w; | |
53 | fSumX2 += x2*w; | |
54 | fSumX3 += x2*x*w; | |
55 | fSumX4 += x2*x2*w; | |
56 | // | |
57 | fSumY +=y*w; | |
58 | fSumYX +=y*x*w; | |
59 | fSumYX2 +=y*x2*w; | |
60 | // | |
61 | fSumZ +=z*w; | |
62 | fSumZX +=z*x*w; | |
63 | fSumZX2 +=z*x2*w; | |
64 | // | |
65 | fX[fNPoints] = x; | |
66 | fY[fNPoints] = y; | |
67 | fZ[fNPoints] = z; | |
68 | fSY[fNPoints] = sy; | |
69 | fSZ[fNPoints] = sz; | |
70 | ||
71 | fNPoints++; | |
72 | ||
73 | } | |
74 | ||
75 | void AliTPCpolyTrack::UpdateParameters() | |
76 | { | |
77 | // | |
78 | // | |
79 | //Update fit parameters | |
80 | if (fNPoints>4){ | |
81 | Fit2(fSumY,fSumYX,fSumYX2,fSumX,fSumX2,fSumX3,fSumX4,fSumW,fA,fB,fC); | |
82 | // Fit2(fSumZ,fSumZX,fSumZX2,fSumX,fSumX2,fSumX3,fSumX4,fNPoints,fD,fE,fF); | |
83 | Fit1(fSumZ,fSumZX,fSumX,fSumX2,fSumW,fD,fE,fF); | |
84 | } | |
85 | else | |
86 | { | |
87 | Fit1(fSumY,fSumYX,fSumX,fSumX2,fSumW,fA,fB,fC); | |
88 | Fit1(fSumZ,fSumZX,fSumX,fSumX2,fSumW,fD,fE,fF); | |
89 | } | |
90 | } | |
91 | ||
0909b376 | 92 | void AliTPCpolyTrack::UpdateParameters(Int_t ny, Int_t nz) |
93 | { | |
94 | // | |
95 | // | |
96 | //Update fit parameters | |
97 | if (ny>1){ | |
98 | Fit2(fSumY,fSumYX,fSumYX2,fSumX,fSumX2,fSumX3,fSumX4,fSumW,fA,fB,fC); | |
99 | } | |
100 | else{ | |
101 | Fit1(fSumY,fSumYX,fSumX,fSumX2,fSumW,fA,fB,fC); | |
102 | } | |
103 | if (nz>1){ | |
104 | Fit2(fSumZ,fSumZX,fSumZX2,fSumX,fSumX2,fSumX3,fSumX4,fNPoints,fD,fE,fF); | |
105 | } | |
106 | else{ | |
107 | Fit1(fSumZ,fSumZX,fSumX,fSumX2,fSumW,fD,fE,fF); | |
108 | } | |
109 | } | |
110 | ||
1627d1c4 | 111 | |
1627d1c4 | 112 | |
113 | void AliTPCpolyTrack::Fit2(Double_t fSumY, Double_t fSumYX, Double_t fSumYX2, | |
114 | Double_t fSumX, Double_t fSumX2, Double_t fSumX3, | |
115 | Double_t fSumX4, Double_t fSumW, | |
116 | Double_t &a, Double_t &b, Double_t &c) | |
117 | { | |
118 | //fit of second order | |
119 | Double_t det = | |
120 | fSumW* (fSumX2*fSumX4-fSumX3*fSumX3) - | |
121 | fSumX* (fSumX*fSumX4-fSumX3*fSumX2)+ | |
122 | fSumX2* (fSumX*fSumX3-fSumX2*fSumX2); | |
123 | ||
124 | if (TMath::Abs(det)> 0.000000000000001) { | |
125 | a = | |
126 | (fSumY * (fSumX2*fSumX4-fSumX3*fSumX3)- | |
127 | fSumX *(fSumYX*fSumX4-fSumYX2*fSumX3)+ | |
128 | fSumX2*(fSumYX*fSumX3-fSumYX2*fSumX2))/det; | |
129 | b= | |
130 | (fSumW*(fSumYX*fSumX4-fSumX3*fSumYX2)- | |
131 | fSumY*(fSumX*fSumX4-fSumX3*fSumX2)+ | |
132 | fSumX2*(fSumX*fSumYX2-fSumYX*fSumX2))/det; | |
133 | c= | |
134 | (fSumW*(fSumX2*fSumYX2-fSumYX*fSumX3)- | |
135 | fSumX*(fSumX*fSumYX2-fSumYX*fSumX2)+ | |
136 | fSumY*(fSumX*fSumX3-fSumX2*fSumX2))/det; | |
137 | } | |
138 | } | |
139 | ||
140 | void AliTPCpolyTrack::Fit1(Double_t fSumY, Double_t fSumYX, | |
141 | Double_t fSumX, Double_t fSumX2, | |
142 | Double_t fSumW, Double_t &a, Double_t &b, Double_t &c) | |
143 | { | |
144 | // | |
145 | // | |
146 | // | |
147 | Double_t det = fSumW*fSumX2-fSumX*fSumX; | |
148 | if (TMath::Abs(det)> 0.000000000000001) { | |
149 | b = (fSumW*fSumYX-fSumX*fSumY)/det; | |
150 | a = (fSumX2*fSumY-fSumX*fSumYX)/det; | |
151 | c = 0; | |
152 | }else{ | |
153 | a =fSumYX/fSumX; | |
154 | b =0; | |
155 | c =0; | |
156 | } | |
157 | ||
158 | } | |
37264142 | 159 | |
160 | void AliTPCpolyTrack::Refit(AliTPCpolyTrack &track, Double_t deltay, Double_t deltaz) | |
161 | { | |
162 | // | |
163 | // refit with cut on distortion | |
164 | // | |
165 | track.Reset(); | |
166 | //first refit to temporary | |
167 | AliTPCpolyTrack track0; | |
330d3170 | 168 | track0.Reset(); |
37264142 | 169 | for (Int_t i=0;i<fNPoints;i++){ |
170 | Double_t y,z; | |
171 | GetFitPoint(fX[i],y,z); | |
172 | if ( (TMath::Abs(y-fY[i])<deltay)&&(TMath::Abs(z-fZ[i])<deltaz)){ | |
173 | track0.AddPoint(fX[i],y,z); | |
174 | } | |
175 | } | |
176 | if (track0.GetN()>2) | |
177 | track0.UpdateParameters(); | |
178 | else | |
179 | return; | |
180 | // | |
181 | for (Int_t i=0;i<fNPoints;i++){ | |
182 | Double_t y,z; | |
183 | track0.GetFitPoint(fX[i],y,z); | |
184 | if ( (TMath::Abs(y-fY[i])<deltay)&&(TMath::Abs(z-fZ[i])<deltaz)){ | |
185 | track.AddPoint(fX[i],y,z); | |
186 | } | |
187 | } | |
188 | if (track.GetN()>2) | |
189 | track.UpdateParameters(); | |
190 | ||
191 | } | |
192 | ||
0909b376 | 193 | void AliTPCpolyTrack::Refit(AliTPCpolyTrack &track, Double_t deltay, Double_t deltaz, Int_t nfirst, Int_t ny, Int_t nz) |
194 | { | |
195 | // | |
196 | // refit with cut on distortion | |
197 | // | |
198 | track.Reset(); | |
199 | //first refit to temporary | |
200 | AliTPCpolyTrack track0; | |
201 | track0.Reset(); | |
202 | for (Int_t i=0;i<fNPoints;i++){ | |
203 | Double_t y,z; | |
204 | GetFitPoint(fX[i],y,z); | |
205 | if ( (TMath::Abs(y-fY[i])<deltay)&&(TMath::Abs(z-fZ[i])<deltaz)){ | |
206 | track0.AddPoint(fX[i],y,z); | |
207 | } | |
208 | } | |
209 | if (track0.GetN()>2){ | |
210 | if (track0.GetN()>nfirst) | |
211 | track0.UpdateParameters(ny,nz); | |
212 | else | |
213 | track0.UpdateParameters(1,1); | |
214 | } | |
215 | else | |
216 | return; | |
217 | // | |
218 | for (Int_t i=0;i<fNPoints;i++){ | |
219 | Double_t y,z; | |
220 | track0.GetFitPoint(fX[i],y,z); | |
221 | if ( (TMath::Abs(y-fY[i])<deltay)&&(TMath::Abs(z-fZ[i])<deltaz)){ | |
222 | track.AddPoint(fX[i],y,z); | |
223 | } | |
224 | } | |
225 | if (track.GetN()>2) | |
226 | track.UpdateParameters(ny,nz); | |
227 | ||
228 | } | |
229 |