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46d29e70 | 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 | $Log$ | |
0a29d0f1 | 18 | Revision 1.8 2001/05/30 12:17:47 hristov |
19 | Loop variables declared once | |
20 | ||
3ab6f951 | 21 | Revision 1.7 2001/05/28 17:07:58 hristov |
22 | Last minute changes; ExB correction in AliTRDclusterizerV1; taking into account of material in G10 TEC frames and material between TEC planes (C.Blume,S.Sedykh) | |
23 | ||
2a941f4e | 24 | Revision 1.4 2000/12/08 16:07:02 cblume |
25 | Update of the tracking by Sergei | |
26 | ||
bbf92647 | 27 | Revision 1.3 2000/10/15 23:40:01 cblume |
28 | Remove AliTRDconst | |
29 | ||
0e9c2ad5 | 30 | Revision 1.2 2000/10/06 16:49:46 cblume |
31 | Made Getters const | |
32 | ||
46d29e70 | 33 | Revision 1.1.2.1 2000/09/22 14:47:52 cblume |
34 | Add the tracking code | |
35 | ||
36 | */ | |
37 | ||
38 | #include <iostream.h> | |
5443e65e | 39 | #include <TObject.h> |
46d29e70 | 40 | |
46d29e70 | 41 | #include "AliTRDgeometry.h" |
42 | #include "AliTRDcluster.h" | |
43 | #include "AliTRDtrack.h" | |
5443e65e | 44 | #include "../TPC/AliTPCtrack.h" |
46d29e70 | 45 | |
46 | ClassImp(AliTRDtrack) | |
47 | ||
48 | ||
49 | //_____________________________________________________________________________ | |
50 | ||
a819a5f7 | 51 | AliTRDtrack::AliTRDtrack(const AliTRDcluster *c, UInt_t index, |
5443e65e | 52 | const Double_t xx[5], const Double_t cc[15], |
53 | Double_t xref, Double_t alpha) : AliKalmanTrack() { | |
46d29e70 | 54 | //----------------------------------------------------------------- |
55 | // This is the main track constructor. | |
56 | //----------------------------------------------------------------- | |
5443e65e | 57 | |
58 | fSeedLab = -1; | |
46d29e70 | 59 | |
60 | fAlpha=alpha; | |
5443e65e | 61 | if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi(); |
62 | if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
63 | ||
46d29e70 | 64 | fX=xref; |
65 | ||
66 | fY=xx[0]; fZ=xx[1]; fC=xx[2]; fE=xx[3]; fT=xx[4]; | |
67 | ||
68 | fCyy=cc[0]; | |
69 | fCzy=cc[1]; fCzz=cc[2]; | |
70 | fCcy=cc[3]; fCcz=cc[4]; fCcc=cc[5]; | |
71 | fCey=cc[6]; fCez=cc[7]; fCec=cc[8]; fCee=cc[9]; | |
72 | fCty=cc[10]; fCtz=cc[11]; fCtc=cc[12]; fCte=cc[13]; fCtt=cc[14]; | |
73 | ||
5443e65e | 74 | fIndex[0]=index; |
75 | SetNumberOfClusters(1); | |
76 | ||
77 | fdEdx=0.; | |
a2b90f83 | 78 | |
5443e65e | 79 | Double_t q = TMath::Abs(c->GetQ()); |
a819a5f7 | 80 | Double_t s = fX*fC - fE, t=fT; |
5443e65e | 81 | if(s*s < 1) q *= TMath::Sqrt((1-s*s)/(1+t*t)); |
82 | ||
83 | fdQdl[0] = q; | |
46d29e70 | 84 | } |
85 | ||
86 | //_____________________________________________________________________________ | |
5443e65e | 87 | AliTRDtrack::AliTRDtrack(const AliTRDtrack& t) : AliKalmanTrack(t) { |
46d29e70 | 88 | // |
89 | // Copy constructor. | |
90 | // | |
91 | ||
5443e65e | 92 | SetLabel(t.GetLabel()); |
93 | fSeedLab=t.GetSeedLabel(); | |
46d29e70 | 94 | |
5443e65e | 95 | SetChi2(t.GetChi2()); |
46d29e70 | 96 | fdEdx=t.fdEdx; |
97 | ||
98 | fAlpha=t.fAlpha; | |
99 | fX=t.fX; | |
100 | ||
101 | fY=t.fY; fZ=t.fZ; fC=t.fC; fE=t.fE; fT=t.fT; | |
102 | ||
103 | fCyy=t.fCyy; | |
104 | fCzy=t.fCzy; fCzz=t.fCzz; | |
105 | fCcy=t.fCcy; fCcz=t.fCcz; fCcc=t.fCcc; | |
106 | fCey=t.fCey; fCez=t.fCez; fCec=t.fCec; fCee=t.fCee; | |
107 | fCty=t.fCty; fCtz=t.fCtz; fCtc=t.fCtc; fCte=t.fCte; fCtt=t.fCtt; | |
108 | ||
5443e65e | 109 | Int_t n=t.GetNumberOfClusters(); |
110 | SetNumberOfClusters(n); | |
111 | for (Int_t i=0; i<n; i++) { | |
a819a5f7 | 112 | fIndex[i]=t.fIndex[i]; |
113 | fdQdl[i]=t.fdQdl[i]; | |
114 | } | |
5443e65e | 115 | } |
116 | ||
117 | //_____________________________________________________________________________ | |
118 | AliTRDtrack::AliTRDtrack(const AliKalmanTrack& t, Double_t alpha) { | |
119 | // | |
120 | // Constructor from AliTPCtrack or AliITStrack . | |
121 | // | |
122 | ||
123 | SetLabel(t.GetLabel()); | |
124 | SetChi2(0.); | |
125 | SetNumberOfClusters(0); | |
126 | ||
127 | fdEdx=0; | |
128 | ||
129 | fAlpha = alpha; | |
130 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
131 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
132 | ||
133 | Double_t x, p[5]; t.GetExternalParameters(x,p); | |
134 | ||
135 | fX=x; | |
136 | ||
137 | x = GetConvConst(); | |
138 | ||
139 | fY=p[0]; fZ=p[1]; fC=p[4]/x; | |
140 | fE=fX*fC-p[2]; fT=p[3]; | |
141 | ||
142 | //Conversion of the covariance matrix | |
143 | Double_t c[15]; t.GetExternalCovariance(c); | |
144 | ||
145 | c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x; | |
146 | ||
147 | Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5]; | |
148 | Double_t c32=fX*c[13] - c[8]; | |
149 | Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12]; | |
150 | ||
151 | fCyy=c[0 ]; | |
152 | fCzy=c[1 ]; fCzz=c[2 ]; | |
153 | fCcy=c[10]; fCcz=c[11]; fCcc=c[14]; | |
154 | fCey=c20; fCez=c21; fCec=c42; fCee=c22; | |
155 | fCty=c[6 ]; fCtz=c[7 ]; fCtc=c[13]; fCte=c32; fCtt=c[9 ]; | |
156 | ||
157 | } | |
158 | ||
159 | //____________________________________________________________________________ | |
160 | void AliTRDtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const { | |
161 | // | |
162 | // This function returns external TRD track representation | |
163 | // | |
164 | xr=fX; | |
165 | x[0]=GetY(); | |
166 | x[1]=GetZ(); | |
167 | x[2]=GetSnp(); | |
168 | x[3]=GetTgl(); | |
169 | x[4]=fC*GetConvConst(); | |
170 | } | |
171 | ||
172 | //_____________________________________________________________________________ | |
173 | void AliTRDtrack::GetExternalCovariance(Double_t cc[15]) const { | |
174 | // | |
175 | // This function returns external representation of the covriance matrix. | |
176 | // | |
177 | Double_t a=GetConvConst(); | |
178 | ||
179 | Double_t c22=fX*fX*fCcc-2*fX*fCec+fCee; | |
180 | Double_t c32=fX*fCtc-fCte; | |
181 | Double_t c20=fX*fCcy-fCey, c21=fX*fCcz-fCez, c42=fX*fCcc-fCec; | |
182 | ||
183 | cc[0 ]=fCyy; | |
184 | cc[1 ]=fCzy; cc[2 ]=fCzz; | |
185 | cc[3 ]=c20; cc[4 ]=c21; cc[5 ]=c22; | |
186 | cc[6 ]=fCty; cc[7 ]=fCtz; cc[8 ]=c32; cc[9 ]=fCtt; | |
187 | cc[10]=fCcy*a; cc[11]=fCcz*a; cc[12]=c42*a; cc[13]=fCtc*a; cc[14]=fCcc*a*a; | |
188 | } | |
189 | ||
46d29e70 | 190 | |
191 | //_____________________________________________________________________________ | |
192 | void AliTRDtrack::GetCovariance(Double_t cc[15]) const { | |
193 | cc[0]=fCyy; | |
194 | cc[1]=fCzy; cc[2]=fCzz; | |
195 | cc[3]=fCcy; cc[4]=fCcz; cc[5]=fCcc; | |
196 | cc[6]=fCey; cc[7]=fCez; cc[8]=fCec; cc[9]=fCee; | |
197 | cc[10]=fCty; cc[11]=fCtz; cc[12]=fCtc; cc[13]=fCte; cc[14]=fCtt; | |
198 | } | |
199 | ||
200 | //_____________________________________________________________________________ | |
2a941f4e | 201 | Int_t AliTRDtrack::Compare(const TObject *o) const { |
46d29e70 | 202 | |
5443e65e | 203 | // Compares tracks according to their Y2 or curvature |
46d29e70 | 204 | |
205 | AliTRDtrack *t=(AliTRDtrack*)o; | |
206 | // Double_t co=t->GetSigmaY2(); | |
207 | // Double_t c =GetSigmaY2(); | |
208 | ||
209 | Double_t co=TMath::Abs(t->GetC()); | |
210 | Double_t c =TMath::Abs(GetC()); | |
211 | ||
212 | if (c>co) return 1; | |
213 | else if (c<co) return -1; | |
214 | return 0; | |
215 | } | |
216 | ||
a819a5f7 | 217 | //_____________________________________________________________________________ |
218 | void AliTRDtrack::CookdEdx(Double_t low, Double_t up) { | |
219 | //----------------------------------------------------------------- | |
220 | // Calculates dE/dX within the "low" and "up" cuts. | |
221 | //----------------------------------------------------------------- | |
5443e65e | 222 | |
a819a5f7 | 223 | Int_t i; |
5443e65e | 224 | Int_t nc=GetNumberOfClusters(); |
a819a5f7 | 225 | |
5443e65e | 226 | Float_t sorted[kMAX_CLUSTERS_PER_TRACK]; |
227 | for (i=0; i < nc; i++) { | |
228 | sorted[i]=fdQdl[i]; | |
229 | } | |
a819a5f7 | 230 | |
231 | Int_t swap; | |
5443e65e | 232 | |
a819a5f7 | 233 | do { |
234 | swap=0; | |
235 | for (i=0; i<nc-1; i++) { | |
236 | if (sorted[i]<=sorted[i+1]) continue; | |
237 | Float_t tmp=sorted[i]; | |
238 | sorted[i]=sorted[i+1]; sorted[i+1]=tmp; | |
239 | swap++; | |
240 | } | |
241 | } while (swap); | |
242 | ||
243 | Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); | |
244 | Float_t dedx=0; | |
245 | for (i=nl; i<=nu; i++) dedx += sorted[i]; | |
246 | dedx /= (nu-nl+1); | |
5443e65e | 247 | |
a819a5f7 | 248 | SetdEdx(dedx); |
249 | } | |
250 | ||
251 | ||
252 | ||
46d29e70 | 253 | //_____________________________________________________________________________ |
254 | Int_t AliTRDtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho,Double_t pm) | |
255 | { | |
256 | // Propagates a track of particle with mass=pm to a reference plane | |
257 | // defined by x=xk through media of density=rho and radiationLength=x0 | |
258 | ||
5443e65e | 259 | |
46d29e70 | 260 | if (TMath::Abs(fC*xk - fE) >= 0.99999) { |
5443e65e | 261 | Int_t n=GetNumberOfClusters(); |
262 | if (n>4) cerr<<n<<" AliTRDtrack warning: Propagation failed !\n"; | |
46d29e70 | 263 | return 0; |
264 | } | |
265 | ||
266 | Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ; | |
5443e65e | 267 | Double_t c1=fC*x1 - fE; |
268 | if((c1*c1) > 1) return 0; | |
269 | Double_t r1=sqrt(1.- c1*c1); | |
270 | Double_t c2=fC*x2 - fE; | |
271 | if((c2*c2) > 1) return 0; | |
272 | Double_t r2=sqrt(1.- c2*c2); | |
46d29e70 | 273 | |
274 | fY += dx*(c1+c2)/(r1+r2); | |
275 | fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT; | |
276 | ||
277 | //f = F - 1 | |
278 | Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2; | |
279 | Double_t f02= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr); | |
280 | Double_t f03=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr); | |
281 | Double_t cr=c1*r2+c2*r1; | |
282 | Double_t f12= dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr); | |
283 | Double_t f13=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr); | |
284 | Double_t f14= dx*cc/cr; | |
285 | ||
286 | //b = C*ft | |
287 | Double_t b00=f02*fCcy + f03*fCey, b01=f12*fCcy + f13*fCey + f14*fCty; | |
288 | Double_t b10=f02*fCcz + f03*fCez, b11=f12*fCcz + f13*fCez + f14*fCtz; | |
289 | Double_t b20=f02*fCcc + f03*fCec, b21=f12*fCcc + f13*fCec + f14*fCtc; | |
290 | Double_t b30=f02*fCec + f03*fCee, b31=f12*fCec + f13*fCee + f14*fCte; | |
291 | Double_t b40=f02*fCtc + f03*fCte, b41=f12*fCtc + f13*fCte + f14*fCtt; | |
292 | ||
293 | //a = f*b = f*C*ft | |
294 | Double_t a00=f02*b20+f03*b30,a01=f02*b21+f03*b31,a11=f12*b21+f13*b31+f14*b41; | |
295 | ||
296 | //F*C*Ft = C + (a + b + bt) | |
297 | fCyy += a00 + 2*b00; | |
298 | fCzy += a01 + b01 + b10; | |
299 | fCcy += b20; | |
300 | fCey += b30; | |
301 | fCty += b40; | |
302 | fCzz += a11 + 2*b11; | |
303 | fCcz += b21; | |
304 | fCez += b31; | |
305 | fCtz += b41; | |
306 | ||
307 | fX=x2; | |
308 | ||
309 | ||
310 | //Multiple scattering ****************** | |
311 | ||
312 | Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ)); | |
313 | Double_t p2=GetPt()*GetPt()*(1.+fT*fT); | |
5443e65e | 314 | p2 = TMath::Min(p2,1e+08); // to avoid division by (1-1) for stiff tracks |
46d29e70 | 315 | Double_t beta2=p2/(p2 + pm*pm); |
316 | ||
317 | Double_t ey=fC*fX - fE, ez=fT; | |
318 | Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey; | |
319 | ||
320 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho; | |
321 | fCcc += xz*xz*theta2; | |
322 | fCec += xz*ez*xy*theta2; | |
323 | fCtc += xz*zz1*theta2; | |
324 | fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2; | |
325 | fCte += ez*zz1*xy*theta2; | |
326 | fCtt += zz1*zz1*theta2; | |
327 | ||
328 | ||
329 | //Energy losses************************ | |
5443e65e | 330 | if (x1 < x2) d=-d; |
46d29e70 | 331 | Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d*rho; |
5443e65e | 332 | SetLength(GetLength()+d); |
333 | ||
334 | cc = fC; | |
46d29e70 | 335 | fC*=(1.- sqrt(p2+pm*pm)/p2*dE); |
5443e65e | 336 | fE+=fX*(fC-cc); |
46d29e70 | 337 | |
338 | return 1; | |
339 | ||
340 | } | |
341 | ||
46d29e70 | 342 | //_____________________________________________________________________________ |
5443e65e | 343 | Int_t AliTRDtrack::Update(const AliTRDcluster *c, Double_t chisq, UInt_t index) |
46d29e70 | 344 | { |
345 | // Assignes found cluster to the track and updates track information | |
346 | ||
a819a5f7 | 347 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); |
46d29e70 | 348 | r00+=fCyy; r01+=fCzy; r11+=fCzz; |
349 | Double_t det=r00*r11 - r01*r01; | |
350 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
351 | ||
352 | Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11; | |
353 | Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11; | |
354 | Double_t k20=fCcy*r00+fCcz*r01, k21=fCcy*r01+fCcz*r11; | |
355 | Double_t k30=fCey*r00+fCez*r01, k31=fCey*r01+fCez*r11; | |
356 | Double_t k40=fCty*r00+fCtz*r01, k41=fCty*r01+fCtz*r11; | |
357 | ||
358 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
359 | Double_t cur=fC + k20*dy + k21*dz, eta=fE + k30*dy + k31*dz; | |
360 | if (TMath::Abs(cur*fX-eta) >= 0.99999) { | |
5443e65e | 361 | Int_t n=GetNumberOfClusters(); |
362 | if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n"; | |
363 | return 0; | |
46d29e70 | 364 | } |
365 | ||
366 | fY += k00*dy + k01*dz; | |
367 | fZ += k10*dy + k11*dz; | |
368 | fC = cur; | |
369 | fE = eta; | |
370 | fT += k40*dy + k41*dz; | |
371 | ||
372 | Double_t c01=fCzy, c02=fCcy, c03=fCey, c04=fCty; | |
373 | Double_t c12=fCcz, c13=fCez, c14=fCtz; | |
374 | ||
375 | fCyy-=k00*fCyy+k01*fCzy; fCzy-=k00*c01+k01*fCzz; | |
376 | fCcy-=k00*c02+k01*c12; fCey-=k00*c03+k01*c13; | |
377 | fCty-=k00*c04+k01*c14; | |
378 | ||
379 | fCzz-=k10*c01+k11*fCzz; | |
380 | fCcz-=k10*c02+k11*c12; fCez-=k10*c03+k11*c13; | |
381 | fCtz-=k10*c04+k11*c14; | |
382 | ||
383 | fCcc-=k20*c02+k21*c12; fCec-=k20*c03+k21*c13; | |
384 | fCtc-=k20*c04+k21*c14; | |
385 | ||
386 | fCee-=k30*c03+k31*c13; | |
387 | fCte-=k30*c04+k31*c14; | |
388 | ||
389 | fCtt-=k40*c04+k41*c14; | |
390 | ||
5443e65e | 391 | Int_t n=GetNumberOfClusters(); |
392 | fIndex[n]=index; | |
393 | SetNumberOfClusters(n+1); | |
46d29e70 | 394 | |
5443e65e | 395 | SetChi2(GetChi2()+chisq); |
46d29e70 | 396 | // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl; |
5443e65e | 397 | |
398 | return 1; | |
46d29e70 | 399 | } |
400 | ||
401 | //_____________________________________________________________________________ | |
402 | Int_t AliTRDtrack::Rotate(Double_t alpha) | |
403 | { | |
404 | // Rotates track parameters in R*phi plane | |
405 | ||
406 | fAlpha += alpha; | |
407 | ||
408 | Double_t x1=fX, y1=fY; | |
409 | Double_t ca=cos(alpha), sa=sin(alpha); | |
410 | Double_t r1=fC*fX - fE; | |
411 | ||
5443e65e | 412 | if (TMath::Abs(r1) >= 0.99999) { |
413 | Int_t n=GetNumberOfClusters(); | |
414 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n"; | |
415 | return 0; | |
416 | } | |
417 | ||
46d29e70 | 418 | fX = x1*ca + y1*sa; |
419 | fY=-x1*sa + y1*ca; | |
420 | fE=fE*ca + (fC*y1 + sqrt(1.- r1*r1))*sa; | |
421 | ||
422 | Double_t r2=fC*fX - fE; | |
423 | if (TMath::Abs(r2) >= 0.99999) { | |
5443e65e | 424 | Int_t n=GetNumberOfClusters(); |
425 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n"; | |
46d29e70 | 426 | return 0; |
427 | } | |
428 | ||
429 | Double_t y0=fY + sqrt(1.- r2*r2)/fC; | |
430 | if ((fY-y0)*fC >= 0.) { | |
5443e65e | 431 | Int_t n=GetNumberOfClusters(); |
432 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !!!\n"; | |
46d29e70 | 433 | return 0; |
434 | } | |
435 | ||
436 | //f = F - 1 | |
437 | Double_t f00=ca-1, f32=(y1 - r1*x1/sqrt(1.- r1*r1))*sa, | |
438 | f30=fC*sa, f33=(ca + sa*r1/sqrt(1.- r1*r1))-1; | |
439 | ||
440 | //b = C*ft | |
441 | Double_t b00=fCyy*f00, b03=fCyy*f30+fCcy*f32+fCey*f33; | |
442 | Double_t b10=fCzy*f00, b13=fCzy*f30+fCcz*f32+fCez*f33; | |
443 | Double_t b20=fCcy*f00, b23=fCcy*f30+fCcc*f32+fCec*f33; | |
444 | Double_t b30=fCey*f00, b33=fCey*f30+fCec*f32+fCee*f33; | |
445 | Double_t b40=fCty*f00, b43=fCty*f30+fCtc*f32+fCte*f33; | |
446 | ||
447 | //a = f*b = f*C*ft | |
448 | Double_t a00=f00*b00, a03=f00*b03, a33=f30*b03+f32*b23+f33*b33; | |
449 | ||
450 | // *** Double_t dy2=fCyy; | |
451 | ||
452 | //F*C*Ft = C + (a + b + bt) | |
453 | fCyy += a00 + 2*b00; | |
454 | fCzy += b10; | |
455 | fCcy += b20; | |
456 | fCey += a03+b30+b03; | |
457 | fCty += b40; | |
458 | fCez += b13; | |
459 | fCec += b23; | |
460 | fCee += a33 + 2*b33; | |
461 | fCte += b43; | |
462 | ||
463 | // *** fCyy+=dy2*sa*sa*r1*r1/(1.- r1*r1); | |
464 | // *** fCzz+=d2y*sa*sa*fT*fT/(1.- r1*r1); | |
465 | ||
466 | return 1; | |
467 | } | |
468 | ||
469 | ||
46d29e70 | 470 | //_____________________________________________________________________________ |
471 | Double_t AliTRDtrack::GetPredictedChi2(const AliTRDcluster *c) const | |
472 | { | |
a819a5f7 | 473 | /* |
474 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); | |
46d29e70 | 475 | r00+=fCyy; r01+=fCzy; r11+=fCzz; |
476 | ||
477 | Double_t det=r00*r11 - r01*r01; | |
478 | if (TMath::Abs(det) < 1.e-10) { | |
479 | if (fN>4) cerr<<fN<<" AliTRDtrack warning: Singular matrix !\n"; | |
480 | return 1e10; | |
481 | } | |
482 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
483 | ||
484 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
485 | ||
486 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; | |
a819a5f7 | 487 | */ |
488 | ||
489 | Double_t dy=c->GetY() - fY; | |
490 | Double_t r00=c->GetSigmaY2(); | |
491 | ||
492 | return (dy*dy)/r00; | |
493 | ||
46d29e70 | 494 | } |
495 | ||
496 | ||
497 | //_________________________________________________________________________ | |
498 | void AliTRDtrack::GetPxPyPz(Double_t& px, Double_t& py, Double_t& pz) const | |
499 | { | |
500 | // Returns reconstructed track momentum in the global system. | |
501 | ||
502 | Double_t pt=TMath::Abs(GetPt()); // GeV/c | |
503 | Double_t r=fC*fX-fE; | |
5443e65e | 504 | |
505 | Double_t y0; | |
506 | if(r > 1) { py = pt; px = 0; } | |
507 | else if(r < -1) { py = -pt; px = 0; } | |
508 | else { | |
509 | y0=fY + sqrt(1.- r*r)/fC; | |
510 | px=-pt*(fY-y0)*fC; //cos(phi); | |
511 | py=-pt*(fE-fX*fC); //sin(phi); | |
512 | } | |
46d29e70 | 513 | pz=pt*fT; |
514 | Double_t tmp=px*TMath::Cos(fAlpha) - py*TMath::Sin(fAlpha); | |
515 | py=px*TMath::Sin(fAlpha) + py*TMath::Cos(fAlpha); | |
516 | px=tmp; | |
517 | ||
518 | } | |
519 | ||
5443e65e | 520 | //_________________________________________________________________________ |
521 | void AliTRDtrack::GetGlobalXYZ(Double_t& x, Double_t& y, Double_t& z) const | |
46d29e70 | 522 | { |
5443e65e | 523 | // Returns reconstructed track coordinates in the global system. |
524 | ||
525 | x = fX; y = fY; z = fZ; | |
526 | Double_t tmp=x*TMath::Cos(fAlpha) - y*TMath::Sin(fAlpha); | |
527 | y=x*TMath::Sin(fAlpha) + y*TMath::Cos(fAlpha); | |
528 | x=tmp; | |
529 | ||
530 | } | |
3ab6f951 | 531 | |
5443e65e | 532 | //_________________________________________________________________________ |
533 | void AliTRDtrack::ResetCovariance() { | |
534 | // | |
535 | // Resets covariance matrix | |
536 | // | |
46d29e70 | 537 | |
5443e65e | 538 | fCyy*=10.; |
539 | fCzy=0.; fCzz*=10.; | |
540 | fCcy=0.; fCcz=0.; fCcc*=10.; | |
541 | fCey=0.; fCez=0.; fCec=0.; fCee*=10.; | |
542 | fCty=0.; fCtz=0.; fCtc=0.; fCte=0.; fCtt*=10.; | |
46d29e70 | 543 | |
5443e65e | 544 | } |