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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 | $Log$ | |
fd621f36 | 18 | Revision 1.13 2002/10/22 15:53:08 alibrary |
19 | Introducing Riostream.h | |
20 | ||
a2cb5b3d | 21 | Revision 1.12 2002/10/14 14:57:44 hristov |
22 | Merging the VirtualMC branch to the main development branch (HEAD) | |
23 | ||
b9d0a01d | 24 | Revision 1.8.10.2 2002/07/24 10:09:31 alibrary |
25 | Updating VirtualMC | |
26 | ||
fd621f36 | 27 | RRevision 1.11 2002/06/13 12:09:58 hristov |
b9d0a01d | 28 | Minor corrections |
29 | ||
ca6c93d6 | 30 | Revision 1.10 2002/06/12 09:54:35 cblume |
31 | Update of tracking code provided by Sergei | |
32 | ||
0a29d0f1 | 33 | Revision 1.8 2001/05/30 12:17:47 hristov |
34 | Loop variables declared once | |
35 | ||
3ab6f951 | 36 | Revision 1.7 2001/05/28 17:07:58 hristov |
37 | 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) | |
38 | ||
2a941f4e | 39 | Revision 1.4 2000/12/08 16:07:02 cblume |
40 | Update of the tracking by Sergei | |
41 | ||
bbf92647 | 42 | Revision 1.3 2000/10/15 23:40:01 cblume |
43 | Remove AliTRDconst | |
44 | ||
0e9c2ad5 | 45 | Revision 1.2 2000/10/06 16:49:46 cblume |
46 | Made Getters const | |
47 | ||
46d29e70 | 48 | Revision 1.1.2.1 2000/09/22 14:47:52 cblume |
49 | Add the tracking code | |
50 | ||
51 | */ | |
52 | ||
a2cb5b3d | 53 | #include <Riostream.h> |
5443e65e | 54 | #include <TObject.h> |
46d29e70 | 55 | |
46d29e70 | 56 | #include "AliTRDgeometry.h" |
57 | #include "AliTRDcluster.h" | |
58 | #include "AliTRDtrack.h" | |
5443e65e | 59 | #include "../TPC/AliTPCtrack.h" |
46d29e70 | 60 | |
61 | ClassImp(AliTRDtrack) | |
62 | ||
63 | ||
64 | //_____________________________________________________________________________ | |
65 | ||
a819a5f7 | 66 | AliTRDtrack::AliTRDtrack(const AliTRDcluster *c, UInt_t index, |
5443e65e | 67 | const Double_t xx[5], const Double_t cc[15], |
68 | Double_t xref, Double_t alpha) : AliKalmanTrack() { | |
46d29e70 | 69 | //----------------------------------------------------------------- |
70 | // This is the main track constructor. | |
71 | //----------------------------------------------------------------- | |
5443e65e | 72 | |
73 | fSeedLab = -1; | |
46d29e70 | 74 | |
75 | fAlpha=alpha; | |
5443e65e | 76 | if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi(); |
77 | if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
78 | ||
46d29e70 | 79 | fX=xref; |
80 | ||
81 | fY=xx[0]; fZ=xx[1]; fC=xx[2]; fE=xx[3]; fT=xx[4]; | |
82 | ||
83 | fCyy=cc[0]; | |
84 | fCzy=cc[1]; fCzz=cc[2]; | |
85 | fCcy=cc[3]; fCcz=cc[4]; fCcc=cc[5]; | |
86 | fCey=cc[6]; fCez=cc[7]; fCec=cc[8]; fCee=cc[9]; | |
87 | fCty=cc[10]; fCtz=cc[11]; fCtc=cc[12]; fCte=cc[13]; fCtt=cc[14]; | |
88 | ||
5443e65e | 89 | fIndex[0]=index; |
90 | SetNumberOfClusters(1); | |
91 | ||
92 | fdEdx=0.; | |
a2b90f83 | 93 | |
5443e65e | 94 | Double_t q = TMath::Abs(c->GetQ()); |
a819a5f7 | 95 | Double_t s = fX*fC - fE, t=fT; |
5443e65e | 96 | if(s*s < 1) q *= TMath::Sqrt((1-s*s)/(1+t*t)); |
97 | ||
98 | fdQdl[0] = q; | |
46d29e70 | 99 | } |
100 | ||
101 | //_____________________________________________________________________________ | |
5443e65e | 102 | AliTRDtrack::AliTRDtrack(const AliTRDtrack& t) : AliKalmanTrack(t) { |
46d29e70 | 103 | // |
104 | // Copy constructor. | |
105 | // | |
106 | ||
5443e65e | 107 | SetLabel(t.GetLabel()); |
108 | fSeedLab=t.GetSeedLabel(); | |
46d29e70 | 109 | |
5443e65e | 110 | SetChi2(t.GetChi2()); |
46d29e70 | 111 | fdEdx=t.fdEdx; |
112 | ||
113 | fAlpha=t.fAlpha; | |
114 | fX=t.fX; | |
115 | ||
116 | fY=t.fY; fZ=t.fZ; fC=t.fC; fE=t.fE; fT=t.fT; | |
117 | ||
118 | fCyy=t.fCyy; | |
119 | fCzy=t.fCzy; fCzz=t.fCzz; | |
120 | fCcy=t.fCcy; fCcz=t.fCcz; fCcc=t.fCcc; | |
121 | fCey=t.fCey; fCez=t.fCez; fCec=t.fCec; fCee=t.fCee; | |
122 | fCty=t.fCty; fCtz=t.fCtz; fCtc=t.fCtc; fCte=t.fCte; fCtt=t.fCtt; | |
123 | ||
5443e65e | 124 | Int_t n=t.GetNumberOfClusters(); |
125 | SetNumberOfClusters(n); | |
126 | for (Int_t i=0; i<n; i++) { | |
a819a5f7 | 127 | fIndex[i]=t.fIndex[i]; |
128 | fdQdl[i]=t.fdQdl[i]; | |
129 | } | |
5443e65e | 130 | } |
131 | ||
132 | //_____________________________________________________________________________ | |
133 | AliTRDtrack::AliTRDtrack(const AliKalmanTrack& t, Double_t alpha) { | |
134 | // | |
135 | // Constructor from AliTPCtrack or AliITStrack . | |
136 | // | |
137 | ||
138 | SetLabel(t.GetLabel()); | |
139 | SetChi2(0.); | |
140 | SetNumberOfClusters(0); | |
141 | ||
142 | fdEdx=0; | |
143 | ||
144 | fAlpha = alpha; | |
145 | if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi(); | |
146 | else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi(); | |
147 | ||
148 | Double_t x, p[5]; t.GetExternalParameters(x,p); | |
149 | ||
150 | fX=x; | |
151 | ||
152 | x = GetConvConst(); | |
153 | ||
154 | fY=p[0]; fZ=p[1]; fC=p[4]/x; | |
155 | fE=fX*fC-p[2]; fT=p[3]; | |
156 | ||
157 | //Conversion of the covariance matrix | |
158 | Double_t c[15]; t.GetExternalCovariance(c); | |
159 | ||
160 | c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x; | |
161 | ||
162 | Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5]; | |
163 | Double_t c32=fX*c[13] - c[8]; | |
164 | Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12]; | |
165 | ||
166 | fCyy=c[0 ]; | |
167 | fCzy=c[1 ]; fCzz=c[2 ]; | |
168 | fCcy=c[10]; fCcz=c[11]; fCcc=c[14]; | |
169 | fCey=c20; fCez=c21; fCec=c42; fCee=c22; | |
170 | fCty=c[6 ]; fCtz=c[7 ]; fCtc=c[13]; fCte=c32; fCtt=c[9 ]; | |
171 | ||
172 | } | |
173 | ||
174 | //____________________________________________________________________________ | |
175 | void AliTRDtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const { | |
176 | // | |
177 | // This function returns external TRD track representation | |
178 | // | |
179 | xr=fX; | |
180 | x[0]=GetY(); | |
181 | x[1]=GetZ(); | |
182 | x[2]=GetSnp(); | |
183 | x[3]=GetTgl(); | |
184 | x[4]=fC*GetConvConst(); | |
185 | } | |
186 | ||
187 | //_____________________________________________________________________________ | |
188 | void AliTRDtrack::GetExternalCovariance(Double_t cc[15]) const { | |
189 | // | |
190 | // This function returns external representation of the covriance matrix. | |
191 | // | |
192 | Double_t a=GetConvConst(); | |
193 | ||
194 | Double_t c22=fX*fX*fCcc-2*fX*fCec+fCee; | |
195 | Double_t c32=fX*fCtc-fCte; | |
196 | Double_t c20=fX*fCcy-fCey, c21=fX*fCcz-fCez, c42=fX*fCcc-fCec; | |
197 | ||
198 | cc[0 ]=fCyy; | |
199 | cc[1 ]=fCzy; cc[2 ]=fCzz; | |
200 | cc[3 ]=c20; cc[4 ]=c21; cc[5 ]=c22; | |
201 | cc[6 ]=fCty; cc[7 ]=fCtz; cc[8 ]=c32; cc[9 ]=fCtt; | |
202 | cc[10]=fCcy*a; cc[11]=fCcz*a; cc[12]=c42*a; cc[13]=fCtc*a; cc[14]=fCcc*a*a; | |
203 | } | |
204 | ||
46d29e70 | 205 | |
206 | //_____________________________________________________________________________ | |
207 | void AliTRDtrack::GetCovariance(Double_t cc[15]) const { | |
208 | cc[0]=fCyy; | |
209 | cc[1]=fCzy; cc[2]=fCzz; | |
210 | cc[3]=fCcy; cc[4]=fCcz; cc[5]=fCcc; | |
211 | cc[6]=fCey; cc[7]=fCez; cc[8]=fCec; cc[9]=fCee; | |
212 | cc[10]=fCty; cc[11]=fCtz; cc[12]=fCtc; cc[13]=fCte; cc[14]=fCtt; | |
213 | } | |
214 | ||
215 | //_____________________________________________________________________________ | |
2a941f4e | 216 | Int_t AliTRDtrack::Compare(const TObject *o) const { |
46d29e70 | 217 | |
5443e65e | 218 | // Compares tracks according to their Y2 or curvature |
46d29e70 | 219 | |
220 | AliTRDtrack *t=(AliTRDtrack*)o; | |
221 | // Double_t co=t->GetSigmaY2(); | |
222 | // Double_t c =GetSigmaY2(); | |
223 | ||
224 | Double_t co=TMath::Abs(t->GetC()); | |
225 | Double_t c =TMath::Abs(GetC()); | |
226 | ||
227 | if (c>co) return 1; | |
228 | else if (c<co) return -1; | |
229 | return 0; | |
230 | } | |
231 | ||
a819a5f7 | 232 | //_____________________________________________________________________________ |
233 | void AliTRDtrack::CookdEdx(Double_t low, Double_t up) { | |
234 | //----------------------------------------------------------------- | |
235 | // Calculates dE/dX within the "low" and "up" cuts. | |
236 | //----------------------------------------------------------------- | |
5443e65e | 237 | |
a819a5f7 | 238 | Int_t i; |
5443e65e | 239 | Int_t nc=GetNumberOfClusters(); |
a819a5f7 | 240 | |
5443e65e | 241 | Float_t sorted[kMAX_CLUSTERS_PER_TRACK]; |
242 | for (i=0; i < nc; i++) { | |
243 | sorted[i]=fdQdl[i]; | |
244 | } | |
a819a5f7 | 245 | |
246 | Int_t swap; | |
5443e65e | 247 | |
a819a5f7 | 248 | do { |
249 | swap=0; | |
250 | for (i=0; i<nc-1; i++) { | |
251 | if (sorted[i]<=sorted[i+1]) continue; | |
252 | Float_t tmp=sorted[i]; | |
253 | sorted[i]=sorted[i+1]; sorted[i+1]=tmp; | |
254 | swap++; | |
255 | } | |
256 | } while (swap); | |
257 | ||
258 | Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); | |
259 | Float_t dedx=0; | |
260 | for (i=nl; i<=nu; i++) dedx += sorted[i]; | |
261 | dedx /= (nu-nl+1); | |
5443e65e | 262 | |
a819a5f7 | 263 | SetdEdx(dedx); |
264 | } | |
265 | ||
266 | ||
267 | ||
fd621f36 | 268 | |
46d29e70 | 269 | //_____________________________________________________________________________ |
270 | Int_t AliTRDtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho,Double_t pm) | |
271 | { | |
272 | // Propagates a track of particle with mass=pm to a reference plane | |
273 | // defined by x=xk through media of density=rho and radiationLength=x0 | |
274 | ||
5443e65e | 275 | |
46d29e70 | 276 | if (TMath::Abs(fC*xk - fE) >= 0.99999) { |
5443e65e | 277 | Int_t n=GetNumberOfClusters(); |
278 | if (n>4) cerr<<n<<" AliTRDtrack warning: Propagation failed !\n"; | |
46d29e70 | 279 | return 0; |
280 | } | |
281 | ||
282 | Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ; | |
5443e65e | 283 | Double_t c1=fC*x1 - fE; |
284 | if((c1*c1) > 1) return 0; | |
285 | Double_t r1=sqrt(1.- c1*c1); | |
286 | Double_t c2=fC*x2 - fE; | |
287 | if((c2*c2) > 1) return 0; | |
288 | Double_t r2=sqrt(1.- c2*c2); | |
46d29e70 | 289 | |
290 | fY += dx*(c1+c2)/(r1+r2); | |
291 | fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT; | |
292 | ||
293 | //f = F - 1 | |
294 | Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2; | |
295 | Double_t f02= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr); | |
296 | Double_t f03=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr); | |
297 | Double_t cr=c1*r2+c2*r1; | |
298 | Double_t f12= dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr); | |
299 | Double_t f13=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr); | |
300 | Double_t f14= dx*cc/cr; | |
301 | ||
302 | //b = C*ft | |
303 | Double_t b00=f02*fCcy + f03*fCey, b01=f12*fCcy + f13*fCey + f14*fCty; | |
304 | Double_t b10=f02*fCcz + f03*fCez, b11=f12*fCcz + f13*fCez + f14*fCtz; | |
305 | Double_t b20=f02*fCcc + f03*fCec, b21=f12*fCcc + f13*fCec + f14*fCtc; | |
306 | Double_t b30=f02*fCec + f03*fCee, b31=f12*fCec + f13*fCee + f14*fCte; | |
307 | Double_t b40=f02*fCtc + f03*fCte, b41=f12*fCtc + f13*fCte + f14*fCtt; | |
308 | ||
309 | //a = f*b = f*C*ft | |
310 | Double_t a00=f02*b20+f03*b30,a01=f02*b21+f03*b31,a11=f12*b21+f13*b31+f14*b41; | |
311 | ||
312 | //F*C*Ft = C + (a + b + bt) | |
313 | fCyy += a00 + 2*b00; | |
314 | fCzy += a01 + b01 + b10; | |
315 | fCcy += b20; | |
316 | fCey += b30; | |
317 | fCty += b40; | |
318 | fCzz += a11 + 2*b11; | |
319 | fCcz += b21; | |
320 | fCez += b31; | |
321 | fCtz += b41; | |
322 | ||
323 | fX=x2; | |
324 | ||
325 | ||
326 | //Multiple scattering ****************** | |
327 | ||
328 | Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ)); | |
329 | Double_t p2=GetPt()*GetPt()*(1.+fT*fT); | |
5443e65e | 330 | p2 = TMath::Min(p2,1e+08); // to avoid division by (1-1) for stiff tracks |
46d29e70 | 331 | Double_t beta2=p2/(p2 + pm*pm); |
332 | ||
333 | Double_t ey=fC*fX - fE, ez=fT; | |
334 | Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey; | |
335 | ||
336 | Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho; | |
337 | fCcc += xz*xz*theta2; | |
338 | fCec += xz*ez*xy*theta2; | |
339 | fCtc += xz*zz1*theta2; | |
340 | fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2; | |
341 | fCte += ez*zz1*xy*theta2; | |
342 | fCtt += zz1*zz1*theta2; | |
343 | ||
344 | ||
345 | //Energy losses************************ | |
5443e65e | 346 | if (x1 < x2) d=-d; |
46d29e70 | 347 | Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d*rho; |
ca6c93d6 | 348 | //PH SetLength(GetLength()+d); |
5443e65e | 349 | |
350 | cc = fC; | |
46d29e70 | 351 | fC*=(1.- sqrt(p2+pm*pm)/p2*dE); |
5443e65e | 352 | fE+=fX*(fC-cc); |
46d29e70 | 353 | |
354 | return 1; | |
355 | ||
356 | } | |
357 | ||
fd621f36 | 358 | |
46d29e70 | 359 | //_____________________________________________________________________________ |
fd621f36 | 360 | Int_t AliTRDtrack::Update(const AliTRDcluster *c, Double_t chisq, UInt_t index, Double_t h01) |
46d29e70 | 361 | { |
362 | // Assignes found cluster to the track and updates track information | |
363 | ||
fd621f36 | 364 | |
365 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2()*100.0; | |
366 | ||
367 | r00+=(fCyy+2.0*h01*fCzy+h01*h01*fCzz); | |
368 | r01+=(fCzy+h01*fCzz); | |
369 | r11+=fCzz; | |
370 | ||
46d29e70 | 371 | Double_t det=r00*r11 - r01*r01; |
372 | Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det; | |
373 | ||
fd621f36 | 374 | // Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11; |
375 | // Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11; | |
376 | // Double_t k20=fCcy*r00+fCcz*r01, k21=fCcy*r01+fCcz*r11; | |
377 | // Double_t k30=fCey*r00+fCez*r01, k31=fCey*r01+fCez*r11; | |
378 | // Double_t k40=fCty*r00+fCtz*r01, k41=fCty*r01+fCtz*r11; | |
379 | ||
380 | Double_t k00=fCyy*r00+fCzy*(r01+h01*r00),k01=fCyy*r01+fCzy*(r11+h01*r01); | |
381 | Double_t k10=fCzy*r00+fCzz*(r01+h01*r00),k11=fCzy*r01+fCzz*(r11+h01*r01); | |
382 | Double_t k20=fCcy*r00+fCcz*(r01+h01*r00),k21=fCcy*r01+fCcz*(r11+h01*r01); | |
383 | Double_t k30=fCey*r00+fCez*(r01+h01*r00),k31=fCey*r01+fCez*(r11+h01*r01); | |
384 | Double_t k40=fCty*r00+fCtz*(r01+h01*r00),k41=fCty*r01+fCtz*(r11+h01*r01); | |
46d29e70 | 385 | |
386 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
fd621f36 | 387 | |
388 | dy=dy+h01*dz; | |
389 | ||
46d29e70 | 390 | Double_t cur=fC + k20*dy + k21*dz, eta=fE + k30*dy + k31*dz; |
391 | if (TMath::Abs(cur*fX-eta) >= 0.99999) { | |
fd621f36 | 392 | // if (fN>4) cerr<<fN<<" AliTRDtrack warning: Filtering failed !\n"; |
5443e65e | 393 | return 0; |
46d29e70 | 394 | } |
395 | ||
396 | fY += k00*dy + k01*dz; | |
397 | fZ += k10*dy + k11*dz; | |
398 | fC = cur; | |
399 | fE = eta; | |
400 | fT += k40*dy + k41*dz; | |
401 | ||
fd621f36 | 402 | |
403 | k01+=h01*k00; | |
404 | k11+=h01*k10; | |
405 | k21+=h01*k20; | |
406 | k31+=h01*k30; | |
407 | k41+=h01*k40; | |
408 | ||
46d29e70 | 409 | Double_t c01=fCzy, c02=fCcy, c03=fCey, c04=fCty; |
410 | Double_t c12=fCcz, c13=fCez, c14=fCtz; | |
411 | ||
412 | fCyy-=k00*fCyy+k01*fCzy; fCzy-=k00*c01+k01*fCzz; | |
413 | fCcy-=k00*c02+k01*c12; fCey-=k00*c03+k01*c13; | |
414 | fCty-=k00*c04+k01*c14; | |
415 | ||
416 | fCzz-=k10*c01+k11*fCzz; | |
417 | fCcz-=k10*c02+k11*c12; fCez-=k10*c03+k11*c13; | |
418 | fCtz-=k10*c04+k11*c14; | |
419 | ||
420 | fCcc-=k20*c02+k21*c12; fCec-=k20*c03+k21*c13; | |
421 | fCtc-=k20*c04+k21*c14; | |
422 | ||
423 | fCee-=k30*c03+k31*c13; | |
424 | fCte-=k30*c04+k31*c14; | |
425 | ||
426 | fCtt-=k40*c04+k41*c14; | |
427 | ||
5443e65e | 428 | Int_t n=GetNumberOfClusters(); |
429 | fIndex[n]=index; | |
430 | SetNumberOfClusters(n+1); | |
46d29e70 | 431 | |
5443e65e | 432 | SetChi2(GetChi2()+chisq); |
fd621f36 | 433 | |
46d29e70 | 434 | // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl; |
5443e65e | 435 | |
436 | return 1; | |
fd621f36 | 437 | |
46d29e70 | 438 | } |
439 | ||
fd621f36 | 440 | |
46d29e70 | 441 | //_____________________________________________________________________________ |
442 | Int_t AliTRDtrack::Rotate(Double_t alpha) | |
443 | { | |
444 | // Rotates track parameters in R*phi plane | |
445 | ||
446 | fAlpha += alpha; | |
447 | ||
448 | Double_t x1=fX, y1=fY; | |
449 | Double_t ca=cos(alpha), sa=sin(alpha); | |
450 | Double_t r1=fC*fX - fE; | |
451 | ||
5443e65e | 452 | if (TMath::Abs(r1) >= 0.99999) { |
453 | Int_t n=GetNumberOfClusters(); | |
454 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n"; | |
455 | return 0; | |
456 | } | |
457 | ||
46d29e70 | 458 | fX = x1*ca + y1*sa; |
459 | fY=-x1*sa + y1*ca; | |
460 | fE=fE*ca + (fC*y1 + sqrt(1.- r1*r1))*sa; | |
461 | ||
462 | Double_t r2=fC*fX - fE; | |
463 | if (TMath::Abs(r2) >= 0.99999) { | |
5443e65e | 464 | Int_t n=GetNumberOfClusters(); |
465 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n"; | |
46d29e70 | 466 | return 0; |
467 | } | |
468 | ||
469 | Double_t y0=fY + sqrt(1.- r2*r2)/fC; | |
470 | if ((fY-y0)*fC >= 0.) { | |
5443e65e | 471 | Int_t n=GetNumberOfClusters(); |
472 | if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !!!\n"; | |
46d29e70 | 473 | return 0; |
474 | } | |
475 | ||
476 | //f = F - 1 | |
477 | Double_t f00=ca-1, f32=(y1 - r1*x1/sqrt(1.- r1*r1))*sa, | |
478 | f30=fC*sa, f33=(ca + sa*r1/sqrt(1.- r1*r1))-1; | |
479 | ||
480 | //b = C*ft | |
481 | Double_t b00=fCyy*f00, b03=fCyy*f30+fCcy*f32+fCey*f33; | |
482 | Double_t b10=fCzy*f00, b13=fCzy*f30+fCcz*f32+fCez*f33; | |
483 | Double_t b20=fCcy*f00, b23=fCcy*f30+fCcc*f32+fCec*f33; | |
484 | Double_t b30=fCey*f00, b33=fCey*f30+fCec*f32+fCee*f33; | |
485 | Double_t b40=fCty*f00, b43=fCty*f30+fCtc*f32+fCte*f33; | |
486 | ||
487 | //a = f*b = f*C*ft | |
488 | Double_t a00=f00*b00, a03=f00*b03, a33=f30*b03+f32*b23+f33*b33; | |
489 | ||
490 | // *** Double_t dy2=fCyy; | |
491 | ||
492 | //F*C*Ft = C + (a + b + bt) | |
493 | fCyy += a00 + 2*b00; | |
494 | fCzy += b10; | |
495 | fCcy += b20; | |
496 | fCey += a03+b30+b03; | |
497 | fCty += b40; | |
498 | fCez += b13; | |
499 | fCec += b23; | |
500 | fCee += a33 + 2*b33; | |
501 | fCte += b43; | |
502 | ||
503 | // *** fCyy+=dy2*sa*sa*r1*r1/(1.- r1*r1); | |
504 | // *** fCzz+=d2y*sa*sa*fT*fT/(1.- r1*r1); | |
505 | ||
506 | return 1; | |
507 | } | |
508 | ||
509 | ||
46d29e70 | 510 | //_____________________________________________________________________________ |
fd621f36 | 511 | Double_t AliTRDtrack::GetPredictedChi2(const AliTRDcluster *c, Double_t h01) const |
46d29e70 | 512 | { |
fd621f36 | 513 | |
a819a5f7 | 514 | Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2(); |
fd621f36 | 515 | |
46d29e70 | 516 | r00+=fCyy; r01+=fCzy; r11+=fCzz; |
517 | ||
518 | Double_t det=r00*r11 - r01*r01; | |
519 | if (TMath::Abs(det) < 1.e-10) { | |
fd621f36 | 520 | Int_t n=GetNumberOfClusters(); |
521 | if (n>4) cerr<<n<<" AliTRDtrack warning: Singular matrix !\n"; | |
46d29e70 | 522 | return 1e10; |
523 | } | |
524 | Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01; | |
525 | ||
526 | Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ; | |
527 | ||
fd621f36 | 528 | dy=dy+h01*dz; |
a819a5f7 | 529 | |
fd621f36 | 530 | return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det; |
a819a5f7 | 531 | |
fd621f36 | 532 | } |
46d29e70 | 533 | |
534 | ||
535 | //_________________________________________________________________________ | |
536 | void AliTRDtrack::GetPxPyPz(Double_t& px, Double_t& py, Double_t& pz) const | |
537 | { | |
538 | // Returns reconstructed track momentum in the global system. | |
539 | ||
540 | Double_t pt=TMath::Abs(GetPt()); // GeV/c | |
541 | Double_t r=fC*fX-fE; | |
5443e65e | 542 | |
543 | Double_t y0; | |
544 | if(r > 1) { py = pt; px = 0; } | |
545 | else if(r < -1) { py = -pt; px = 0; } | |
546 | else { | |
547 | y0=fY + sqrt(1.- r*r)/fC; | |
548 | px=-pt*(fY-y0)*fC; //cos(phi); | |
549 | py=-pt*(fE-fX*fC); //sin(phi); | |
550 | } | |
46d29e70 | 551 | pz=pt*fT; |
552 | Double_t tmp=px*TMath::Cos(fAlpha) - py*TMath::Sin(fAlpha); | |
553 | py=px*TMath::Sin(fAlpha) + py*TMath::Cos(fAlpha); | |
554 | px=tmp; | |
555 | ||
556 | } | |
557 | ||
5443e65e | 558 | //_________________________________________________________________________ |
559 | void AliTRDtrack::GetGlobalXYZ(Double_t& x, Double_t& y, Double_t& z) const | |
46d29e70 | 560 | { |
5443e65e | 561 | // Returns reconstructed track coordinates in the global system. |
562 | ||
563 | x = fX; y = fY; z = fZ; | |
564 | Double_t tmp=x*TMath::Cos(fAlpha) - y*TMath::Sin(fAlpha); | |
565 | y=x*TMath::Sin(fAlpha) + y*TMath::Cos(fAlpha); | |
566 | x=tmp; | |
567 | ||
568 | } | |
3ab6f951 | 569 | |
5443e65e | 570 | //_________________________________________________________________________ |
571 | void AliTRDtrack::ResetCovariance() { | |
572 | // | |
573 | // Resets covariance matrix | |
574 | // | |
46d29e70 | 575 | |
5443e65e | 576 | fCyy*=10.; |
577 | fCzy=0.; fCzz*=10.; | |
578 | fCcy=0.; fCcz=0.; fCcc*=10.; | |
579 | fCey=0.; fCez=0.; fCec=0.; fCee*=10.; | |
580 | fCty=0.; fCtz=0.; fCtc=0.; fCte=0.; fCtt*=10.; | |
46d29e70 | 581 | |
5443e65e | 582 | } |