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Replacing array of objects by array of pointers
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73042f01 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
803d1ab0 16/* $Id$ */
0938c7d3 17
73042f01 18//-----------------------------------------------------------------
19// Implementation of the TPC track class
7c27857f 20// This class is used by the AliTPCtracker class
21// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
73042f01 22//-----------------------------------------------------------------
23
19364939 24#include <Riostream.h>
b19a0509 25
73042f01 26#include "AliTPCtrack.h"
7c27857f 27#include "AliCluster.h"
83d73500 28#include "AliESDtrack.h"
73042f01 29
30ClassImp(AliTPCtrack)
b9de75e1 31
e3f7105e 32//_________________________________________________________________________
33AliTPCtrack::AliTPCtrack(): AliKalmanTrack()
34{
2fc0c115 35 //-------------------------------------------------
36 // default constructor
37 //-------------------------------------------------
e3f7105e 38 fX = fP0 = fP1 = fP2 = fP3 = fP3 = fP4 = 0.0;
39 fAlpha = fdEdx = 0.0;
24de2d6d 40 fNumber = 0; // [SR, 01.04.2003]
81e97e0d 41 for (Int_t i=0; i<3;i++) {fKinkIndexes[i]=0; fV0Indexes[i]=0;}
e3f7105e 42}
43
73042f01 44//_________________________________________________________________________
51ad6848 45
46
47
73042f01 48AliTPCtrack::AliTPCtrack(UInt_t index, const Double_t xx[5],
b19a0509 49const Double_t cc[15], Double_t xref, Double_t alpha) : AliKalmanTrack() {
73042f01 50 //-----------------------------------------------------------------
51 // This is the main track constructor.
52 //-----------------------------------------------------------------
73042f01 53 fX=xref;
be9c5115 54 fAlpha=alpha;
55 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
56 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
57 fdEdx=0.;
73042f01 58
b19a0509 59 fP0=xx[0]; fP1=xx[1]; fP2=xx[2]; fP3=xx[3]; fP4=xx[4];
73042f01 60
b19a0509 61 fC00=cc[0];
62 fC10=cc[1]; fC11=cc[2];
63 fC20=cc[3]; fC21=cc[4]; fC22=cc[5];
64 fC30=cc[6]; fC31=cc[7]; fC32=cc[8]; fC33=cc[9];
65 fC40=cc[10]; fC41=cc[11]; fC42=cc[12]; fC43=cc[13]; fC44=cc[14];
73042f01 66
be9c5115 67 fIndex[0]=index;
68 SetNumberOfClusters(1);
51584047 69 //
70 //MI
71 fSdEdx = 0;
72 fNFoundable = 0;
73 fBConstrain = 0;
74 fLastPoint = 0;
75 fFirstPoint = 0;
76 fRemoval = 0;
77 fTrackType = 0;
78 fLab2 = 0;
51ad6848 79 for (Int_t i=0; i<3;i++) fKinkIndexes[i]=0;
81e97e0d 80 for (Int_t i=0; i<3;i++) fV0Indexes[i]=0;
b9de75e1 81}
82
83d73500 83//_____________________________________________________________________________
84AliTPCtrack::AliTPCtrack(const AliESDtrack& t) : AliKalmanTrack() {
85 //-----------------------------------------------------------------
86 // Conversion AliESDtrack -> AliTPCtrack.
87 //-----------------------------------------------------------------
88 SetNumberOfClusters(t.GetTPCclusters(fIndex));
89 SetLabel(t.GetLabel());
90 SetMass(t.GetMass());
51ad6848 91 for (Int_t i=0; i<3;i++) fKinkIndexes[i]=t.GetKinkIndex(i);
81e97e0d 92 for (Int_t i=0; i<3;i++) fV0Indexes[i]=t.GetV0Index(i);
83d73500 93
94 fdEdx = t.GetTPCsignal();
95 fAlpha = t.GetAlpha();
96 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
97 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
98
99 //Conversion of the track parameters
100 Double_t x,p[5]; t.GetExternalParameters(x,p);
51ad6848 101 Double_t c[15]; t.GetExternalCovariance(c);
102
83d73500 103 fX=x; x=GetConvConst();
104 fP0=p[0];
105 fP1=p[1];
106 fP3=p[3];
107 fP4=p[4]/x;
108 fP2=fP4*fX - p[2];
109
110 //Conversion of the covariance matrix
83d73500 111 c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x;
112
113 Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5];
114 Double_t c32=fX*c[13] - c[8];
115 Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12];
116
117 fC00=c[0 ];
118 fC10=c[1 ]; fC11=c[2 ];
119 fC20=c20; fC21=c21; fC22=c22;
120 fC30=c[6 ]; fC31=c[7 ]; fC32=c32; fC33=c[9 ];
121 fC40=c[10]; fC41=c[11]; fC42=c42; fC43=c[13]; fC44=c[14];
122
0798b21e 123 if ((t.GetStatus()&AliESDtrack::kTIME) == 0) return;
83d73500 124 StartTimeIntegral();
125 Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times);
126 SetIntegratedLength(t.GetIntegratedLength());
51584047 127 //
128 //MI
129 fSdEdx = 0;
130 fNFoundable = 0;
131 fBConstrain = 0;
132 fLastPoint = 0;
133 fFirstPoint = 0;
134 fRemoval = 0;
135 fTrackType = 0;
136 fLab2 = 0;
babd135a 137 // SetFakeRatio(t.GetTPCFakeRatio());
83d73500 138}
139
73042f01 140//_____________________________________________________________________________
b19a0509 141AliTPCtrack::AliTPCtrack(const AliTPCtrack& t) : AliKalmanTrack(t) {
73042f01 142 //-----------------------------------------------------------------
143 // This is a track copy constructor.
144 //-----------------------------------------------------------------
be9c5115 145 fX=t.fX;
146 fAlpha=t.fAlpha;
73042f01 147 fdEdx=t.fdEdx;
148
be9c5115 149 fP0=t.fP0; fP1=t.fP1; fP2=t.fP2; fP3=t.fP3; fP4=t.fP4;
150
151 fC00=t.fC00;
152 fC10=t.fC10; fC11=t.fC11;
153 fC20=t.fC20; fC21=t.fC21; fC22=t.fC22;
154 fC30=t.fC30; fC31=t.fC31; fC32=t.fC32; fC33=t.fC33;
155 fC40=t.fC40; fC41=t.fC41; fC42=t.fC42; fC43=t.fC43; fC44=t.fC44;
156
176aff27 157 //Int_t n=GetNumberOfClusters();
51584047 158 for (Int_t i=0; i<kMaxRow; i++) fIndex[i]=t.fIndex[i];
159 //
160 //MI
161 fSdEdx = t.fSdEdx;
162 fNFoundable = t.fNFoundable;
163 fBConstrain = t.fBConstrain;
164 fLastPoint = t.fLastPoint;
165 fFirstPoint = t.fFirstPoint;
166 fRemoval = t.fRemoval ;
167 fTrackType = t.fTrackType;
168 fLab2 = t.fLab2;
51ad6848 169 for (Int_t i=0; i<3;i++) fKinkIndexes[i]=t.fKinkIndexes[i];
81e97e0d 170 for (Int_t i=0; i<3;i++) fV0Indexes[i]=t.fV0Indexes[i];
be9c5115 171}
172
173//_____________________________________________________________________________
174Int_t AliTPCtrack::Compare(const TObject *o) const {
175 //-----------------------------------------------------------------
176 // This function compares tracks according to the their curvature
177 //-----------------------------------------------------------------
178 AliTPCtrack *t=(AliTPCtrack*)o;
024a7fe9 179 //Double_t co=TMath::Abs(t->Get1Pt());
180 //Double_t c =TMath::Abs(Get1Pt());
181 Double_t co=t->GetSigmaY2()*t->GetSigmaZ2();
182 Double_t c =GetSigmaY2()*GetSigmaZ2();
be9c5115 183 if (c>co) return 1;
184 else if (c<co) return -1;
185 return 0;
186}
187
188//_____________________________________________________________________________
189void AliTPCtrack::GetExternalCovariance(Double_t cc[15]) const {
190 //-------------------------------------------------------------------------
191 // This function returns an external representation of the covriance matrix.
192 // (See comments in AliTPCtrack.h about external track representation)
193 //-------------------------------------------------------------------------
9b280d80 194 Double_t a=GetConvConst();
be9c5115 195
b9de75e1 196 Double_t c22=fX*fX*fC44-2*fX*fC42+fC22;
197 Double_t c32=fX*fC43-fC32;
198 Double_t c20=fX*fC40-fC20, c21=fX*fC41-fC21, c42=fX*fC44-fC42;
be9c5115 199
200 cc[0 ]=fC00;
201 cc[1 ]=fC10; cc[2 ]=fC11;
202 cc[3 ]=c20; cc[4 ]=c21; cc[5 ]=c22;
b9de75e1 203 cc[6 ]=fC30; cc[7 ]=fC31; cc[8 ]=c32; cc[9 ]=fC33;
204 cc[10]=fC40*a; cc[11]=fC41*a; cc[12]=c42*a; cc[13]=fC43*a; cc[14]=fC44*a*a;
be9c5115 205
206}
207
208//_____________________________________________________________________________
209Double_t AliTPCtrack::GetPredictedChi2(const AliCluster *c) const
210{
211 //-----------------------------------------------------------------
212 // This function calculates a predicted chi2 increment.
213 //-----------------------------------------------------------------
214 Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2();
215 r00+=fC00; r01+=fC10; r11+=fC11;
216
217 Double_t det=r00*r11 - r01*r01;
218 if (TMath::Abs(det) < 1.e-10) {
219 Int_t n=GetNumberOfClusters();
220 if (n>4) cerr<<n<<" AliKalmanTrack warning: Singular matrix !\n";
221 return 1e10;
222 }
223 Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01;
224
225 Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1;
226
227 return (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det;
73042f01 228}
229
c630aafd 230Double_t AliTPCtrack::GetYat(Double_t xk) const {
231//-----------------------------------------------------------------
232// This function calculates the Y-coordinate of a track at the plane x=xk.
233//-----------------------------------------------------------------
234 Double_t c1=fP4*fX - fP2, r1=TMath::Sqrt(1.- c1*c1);
df02fd67 235 Double_t c2=fP4*xk - fP2;
236 if (c2*c2>0.99999) {
237 Int_t n=GetNumberOfClusters();
238 if (n>4) cerr<<n<<"AliTPCtrack::GetYat: can't evaluate the y-coord !\n";
239 return 1e10;
240 }
241 Double_t r2=TMath::Sqrt(1.- c2*c2);
c630aafd 242 return fP0 + (xk-fX)*(c1+c2)/(r1+r2);
243}
244
73042f01 245//_____________________________________________________________________________
176aff27 246Int_t AliTPCtrack::PropagateTo(Double_t xk,Double_t /*x0*/,Double_t rho) {
73042f01 247 //-----------------------------------------------------------------
248 // This function propagates a track to a reference plane x=xk.
249 //-----------------------------------------------------------------
1627d1c4 250 if (TMath::Abs(fP4*xk - fP2) >= 0.9) {
251 // Int_t n=GetNumberOfClusters();
252 //if (n>4) cerr<<n<<" AliTPCtrack warning: Propagation failed !\n";
73042f01 253 return 0;
254 }
e3f7105e 255
256 // old position for time [SR, GSI 17.02.2003]
257 Double_t oldX = fX;
258 Double_t oldY = fP0;
259 Double_t oldZ = fP1;
260 //
73042f01 261
b19a0509 262 Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fP0, z1=fP1;
b9de75e1 263 Double_t c1=fP4*x1 - fP2, r1=sqrt(1.- c1*c1);
264 Double_t c2=fP4*x2 - fP2, r2=sqrt(1.- c2*c2);
73042f01 265
b19a0509 266 fP0 += dx*(c1+c2)/(r1+r2);
b9de75e1 267 fP1 += dx*(c1+c2)/(c1*r2 + c2*r1)*fP3;
73042f01 268
269 //f = F - 1
270 Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2;
b19a0509 271 Double_t f02=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr);
b9de75e1 272 Double_t f04= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr);
73042f01 273 Double_t cr=c1*r2+c2*r1;
b9de75e1 274 Double_t f12=-dx*fP3*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr);
275 Double_t f13= dx*cc/cr;
276 Double_t f14=dx*fP3*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr);
73042f01 277
278 //b = C*ft
b9de75e1 279 Double_t b00=f02*fC20 + f04*fC40, b01=f12*fC20 + f14*fC40 + f13*fC30;
280 Double_t b10=f02*fC21 + f04*fC41, b11=f12*fC21 + f14*fC41 + f13*fC31;
281 Double_t b20=f02*fC22 + f04*fC42, b21=f12*fC22 + f14*fC42 + f13*fC32;
282 Double_t b30=f02*fC32 + f04*fC43, b31=f12*fC32 + f14*fC43 + f13*fC33;
283 Double_t b40=f02*fC42 + f04*fC44, b41=f12*fC42 + f14*fC44 + f13*fC43;
73042f01 284
285 //a = f*b = f*C*ft
b9de75e1 286 Double_t a00=f02*b20+f04*b40,a01=f02*b21+f04*b41,a11=f12*b21+f14*b41+f13*b31;
73042f01 287
288 //F*C*Ft = C + (a + b + bt)
b19a0509 289 fC00 += a00 + 2*b00;
290 fC10 += a01 + b01 + b10;
291 fC20 += b20;
292 fC30 += b30;
293 fC40 += b40;
294 fC11 += a11 + 2*b11;
295 fC21 += b21;
296 fC31 += b31;
297 fC41 += b41;
73042f01 298
299 fX=x2;
300
301 //Multiple scattering******************
b19a0509 302 Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fP0)*(y1-fP0)+(z1-fP1)*(z1-fP1));
be9c5115 303 Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
7f6ddf58 304 Double_t beta2=p2/(p2 + GetMass()*GetMass());
babd135a 305 beta2 = TMath::Min(beta2,0.99999999999);
024a7fe9 306 //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho;
307 Double_t theta2=1.0259e-6*10*10/20/(beta2*p2)*d*rho;
73042f01 308
b9de75e1 309 Double_t ey=fP4*fX - fP2, ez=fP3;
310 Double_t xz=fP4*ez, zz1=ez*ez+1, xy=fP2+ey;
982aff31 311
b19a0509 312 fC22 += (2*ey*ez*ez*fP2+1-ey*ey+ez*ez+fP2*fP2*ez*ez)*theta2;
b9de75e1 313 fC32 += ez*zz1*xy*theta2;
314 fC33 += zz1*zz1*theta2;
315 fC42 += xz*ez*xy*theta2;
316 fC43 += xz*zz1*theta2;
317 fC44 += xz*xz*theta2;
982aff31 318 /*
319 //
320 //MI coeficints
321 Double_t dc22 = (1-ey*ey+xz*xz*fX*fX)*theta2;
322 Double_t dc32 = (xz*fX*zz1)*theta2;
323 Double_t dc33 = (zz1*zz1)*theta2;
324 Double_t dc42 = (xz*fX*xz)*theta2;
325 Double_t dc43 = (zz1*xz)*theta2;
326 Double_t dc44 = (xz*xz)*theta2;
327 fC22 += dc22;
328 fC32 += dc32;
329 fC33 += dc33;
330 fC42 += dc42;
331 fC43 += dc43;
332 fC44 += dc44;
333 */
73042f01 334 //Energy losses************************
335 Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d*rho;
336 if (x1 < x2) dE=-dE;
b9de75e1 337 cc=fP4;
982aff31 338
339 //Double_t E = sqrt(p2+GetMass()*GetMass());
340 //Double_t mifac = TMath::Sqrt(1.+dE*dE/p2+2*E*dE/p2)-1;
341 //Double_t belfac = E*dE/p2;
342 //
7f6ddf58 343 fP4*=(1.- sqrt(p2+GetMass()*GetMass())/p2*dE);
b9de75e1 344 fP2+=fX*(fP4-cc);
73042f01 345
e3f7105e 346 // Integrated Time [SR, GSI, 17.02.2003]
0fa7dfa7 347 if (x1 < x2)
348 if (IsStartedTimeIntegral()) {
e3f7105e 349 Double_t l2 = (fX-oldX)*(fX-oldX)+(fP0-oldY)*(fP0-oldY)+(fP1-oldZ)*(fP1-oldZ);
350 AddTimeStep(TMath::Sqrt(l2));
351 }
352 //
353
73042f01 354 return 1;
355}
356
357//_____________________________________________________________________________
7f6ddf58 358Int_t AliTPCtrack::PropagateToVertex(Double_t x0,Double_t rho)
73042f01 359{
360 //-----------------------------------------------------------------
361 // This function propagates tracks to the "vertex".
362 //-----------------------------------------------------------------
b9de75e1 363 Double_t c=fP4*fX - fP2;
364 Double_t tgf=-fP2/(fP4*fP0 + sqrt(1-c*c));
73042f01 365 Double_t snf=tgf/sqrt(1.+ tgf*tgf);
b9de75e1 366 Double_t xv=(fP2+snf)/fP4;
7f6ddf58 367 return PropagateTo(xv,x0,rho);
73042f01 368}
369
370//_____________________________________________________________________________
be9c5115 371Int_t AliTPCtrack::Update(const AliCluster *c, Double_t chisq, UInt_t index) {
73042f01 372 //-----------------------------------------------------------------
373 // This function associates a cluster with this track.
374 //-----------------------------------------------------------------
375 Double_t r00=c->GetSigmaY2(), r01=0., r11=c->GetSigmaZ2();
b19a0509 376 r00+=fC00; r01+=fC10; r11+=fC11;
73042f01 377 Double_t det=r00*r11 - r01*r01;
378 Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
379
b19a0509 380 Double_t k00=fC00*r00+fC10*r01, k01=fC00*r01+fC10*r11;
381 Double_t k10=fC10*r00+fC11*r01, k11=fC10*r01+fC11*r11;
382 Double_t k20=fC20*r00+fC21*r01, k21=fC20*r01+fC21*r11;
383 Double_t k30=fC30*r00+fC31*r01, k31=fC30*r01+fC31*r11;
384 Double_t k40=fC40*r00+fC41*r01, k41=fC40*r01+fC41*r11;
73042f01 385
b19a0509 386 Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1;
b9de75e1 387 Double_t cur=fP4 + k40*dy + k41*dz, eta=fP2 + k20*dy + k21*dz;
1627d1c4 388 if (TMath::Abs(cur*fX-eta) >= 0.9) {
389 // Int_t n=GetNumberOfClusters();
390 //if (n>4) cerr<<n<<" AliTPCtrack warning: Filtering failed !\n";
be9c5115 391 return 0;
73042f01 392 }
393
b19a0509 394 fP0 += k00*dy + k01*dz;
395 fP1 += k10*dy + k11*dz;
396 fP2 = eta;
b9de75e1 397 fP3 += k30*dy + k31*dz;
398 fP4 = cur;
73042f01 399
b19a0509 400 Double_t c01=fC10, c02=fC20, c03=fC30, c04=fC40;
401 Double_t c12=fC21, c13=fC31, c14=fC41;
73042f01 402
b19a0509 403 fC00-=k00*fC00+k01*fC10; fC10-=k00*c01+k01*fC11;
404 fC20-=k00*c02+k01*c12; fC30-=k00*c03+k01*c13;
405 fC40-=k00*c04+k01*c14;
73042f01 406
b19a0509 407 fC11-=k10*c01+k11*fC11;
408 fC21-=k10*c02+k11*c12; fC31-=k10*c03+k11*c13;
409 fC41-=k10*c04+k11*c14;
73042f01 410
b19a0509 411 fC22-=k20*c02+k21*c12; fC32-=k20*c03+k21*c13;
412 fC42-=k20*c04+k21*c14;
73042f01 413
b19a0509 414 fC33-=k30*c03+k31*c13;
b9de75e1 415 fC43-=k40*c03+k41*c13;
73042f01 416
b19a0509 417 fC44-=k40*c04+k41*c14;
73042f01 418
be9c5115 419 Int_t n=GetNumberOfClusters();
420 fIndex[n]=index;
421 SetNumberOfClusters(n+1);
422 SetChi2(GetChi2()+chisq);
423
424 return 1;
73042f01 425}
426
427//_____________________________________________________________________________
428Int_t AliTPCtrack::Rotate(Double_t alpha)
429{
430 //-----------------------------------------------------------------
431 // This function rotates this track.
432 //-----------------------------------------------------------------
433 fAlpha += alpha;
be9c5115 434 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
435 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
73042f01 436
b19a0509 437 Double_t x1=fX, y1=fP0;
73042f01 438 Double_t ca=cos(alpha), sa=sin(alpha);
b9de75e1 439 Double_t r1=fP4*fX - fP2;
73042f01 440
441 fX = x1*ca + y1*sa;
b19a0509 442 fP0=-x1*sa + y1*ca;
b9de75e1 443 fP2=fP2*ca + (fP4*y1 + sqrt(1.- r1*r1))*sa;
73042f01 444
b9de75e1 445 Double_t r2=fP4*fX - fP2;
73042f01 446 if (TMath::Abs(r2) >= 0.99999) {
be9c5115 447 Int_t n=GetNumberOfClusters();
448 if (n>4) cerr<<n<<" AliTPCtrack warning: Rotation failed !\n";
73042f01 449 return 0;
450 }
451
b9de75e1 452 Double_t y0=fP0 + sqrt(1.- r2*r2)/fP4;
453 if ((fP0-y0)*fP4 >= 0.) {
be9c5115 454 Int_t n=GetNumberOfClusters();
455 if (n>4) cerr<<n<<" AliTPCtrack warning: Rotation failed !!!\n";
73042f01 456 return 0;
457 }
458
459 //f = F - 1
b9de75e1 460 Double_t f00=ca-1, f24=(y1 - r1*x1/sqrt(1.- r1*r1))*sa,
461 f20=fP4*sa, f22=(ca + sa*r1/sqrt(1.- r1*r1))-1;
73042f01 462
463 //b = C*ft
b9de75e1 464 Double_t b00=fC00*f00, b02=fC00*f20+fC40*f24+fC20*f22;
465 Double_t b10=fC10*f00, b12=fC10*f20+fC41*f24+fC21*f22;
466 Double_t b20=fC20*f00, b22=fC20*f20+fC42*f24+fC22*f22;
467 Double_t b30=fC30*f00, b32=fC30*f20+fC43*f24+fC32*f22;
468 Double_t b40=fC40*f00, b42=fC40*f20+fC44*f24+fC42*f22;
73042f01 469
470 //a = f*b = f*C*ft
b9de75e1 471 Double_t a00=f00*b00, a02=f00*b02, a22=f20*b02+f24*b42+f22*b22;
73042f01 472
473 // *** Double_t dy2=fCyy;
474
475 //F*C*Ft = C + (a + b + bt)
b19a0509 476 fC00 += a00 + 2*b00;
477 fC10 += b10;
478 fC20 += a02+b20+b02;
479 fC30 += b30;
480 fC40 += b40;
481 fC21 += b12;
482 fC32 += b32;
483 fC22 += a22 + 2*b22;
484 fC42 += b42;
73042f01 485
486 // *** fCyy+=dy2*sa*sa*r1*r1/(1.- r1*r1);
487 // *** fCzz+=d2y*sa*sa*fT*fT/(1.- r1*r1);
488
489 return 1;
490}
491
b9de75e1 492void AliTPCtrack::ResetCovariance() {
493 //------------------------------------------------------------------
494 //This function makes a track forget its history :)
495 //------------------------------------------------------------------
496
497 fC00*=10.;
498 fC10=0.; fC11*=10.;
499 fC20=0.; fC21=0.; fC22*=10.;
500 fC30=0.; fC31=0.; fC32=0.; fC33*=10.;
501 fC40=0.; fC41=0.; fC42=0.; fC43=0.; fC44*=10.;
502
73042f01 503}
77e58468 504
505////////////////////////////////////////////////////////////////////////
506Double_t AliTPCtrack::Phi() const {
7c27857f 507//
508//
509//
77e58468 510 Double_t phi = TMath::ASin(GetSnp()) + fAlpha;
511 if (phi<0) phi+=2*TMath::Pi();
512 if (phi>=2*TMath::Pi()) phi-=2*TMath::Pi();
513 return phi;
514}
515////////////////////////////////////////////////////////////////////////
516
51584047 517
518
519////////////////////////////////////////////////////////////////////////
520// MI ADDITION
521
522Float_t AliTPCtrack::Density(Int_t row0, Int_t row1)
523{
524 //
525 // calculate cluster density
526 Int_t good = 0;
527 Int_t found = 0;
528 //if (row0<fFirstPoint) row0 = fFirstPoint;
529 if (row1>fLastPoint) row1 = fLastPoint;
530
531
532 for (Int_t i=row0;i<=row1;i++){
533 // Int_t index = fClusterIndex[i];
534 Int_t index = fIndex[i];
535 if (index!=-1) good++;
536 if (index>0) found++;
537 }
538 Float_t density=0;
539 if (good>0) density = Float_t(found)/Float_t(good);
540 return density;
541}
542
543
544Float_t AliTPCtrack::Density2(Int_t row0, Int_t row1)
545{
546 //
547 // calculate cluster density
548 Int_t good = 0;
549 Int_t found = 0;
550 //
551 for (Int_t i=row0;i<=row1;i++){
552 Int_t index = fIndex[i];
553 if (index!=-1) good++;
554 if (index>0) found++;
555 }
556 Float_t density=0;
557 if (good>0) density = Float_t(found)/Float_t(good);
558 return density;
559}
560
561
562Double_t AliTPCtrack::GetZat0() const
563{
564 //
565 // return virtual z - supposing that x = 0
566 if (TMath::Abs(fP2)>1) return 0;
567 if (TMath::Abs(fX*fP4-fP2)>1) return 0;
568 Double_t vz = fP1+fP3/fP4*(asin(-fP2)-asin(fX*fP4-fP2));
569 return vz;
570}
571
572
573Double_t AliTPCtrack::GetD(Double_t x, Double_t y) const {
574 //------------------------------------------------------------------
575 // This function calculates the transverse impact parameter
576 // with respect to a point with global coordinates (x,y)
577 //------------------------------------------------------------------
578 //Double_t xt=fX, yt=fP0;
579
580 Double_t sn=TMath::Sin(fAlpha), cs=TMath::Cos(fAlpha);
581 Double_t a = x*cs + y*sn;
582 y = -x*sn + y*cs; x=a;
583 //
584 Double_t r = TMath::Abs(1/fP4);
585 Double_t x0 = TMath::Abs(fP2*r);
586 Double_t y0 = fP0;
587 y0= fP0+TMath::Sqrt(1-(fP4*fX-fP2)*(fP4*fX-fP2))/fP4;
588
589 Double_t delta = TMath::Sqrt((x-x0)*(x-x0)+(y-y0)*(y-y0));
590 // Double_t delta = TMath::Sqrt(TMath::Abs(x*x-2*x0*x+x0*x0+ y*y-2*y*y0+y0*y0));
591 delta -= TMath::Abs(r);
592 return delta;
593}
51ad6848 594
595//
596//
597
598void AliTPCtrack::UpdatePoints()
599{
600 //--------------------------------------------------
601 //calculates first ,amx dens and last points
602 //--------------------------------------------------
603 Float_t density[160];
604 for (Int_t i=0;i<160;i++) density[i]=-1.;
605 fPoints[0]= 160;
606 fPoints[1] = -1;
607 //
608 Int_t ngood=0;
609 Int_t undeff=0;
610 Int_t nall =0;
611 Int_t range=20;
612 for (Int_t i=0;i<160;i++){
613 Int_t last = i-range;
614 if (nall<range) nall++;
615 if (last>=0){
616 if (fIndex[last]>0&& (fIndex[last]&0x8000)==0) ngood--;
617 if (fIndex[last]==-1) undeff--;
618 }
619 if (fIndex[i]>0&& (fIndex[i]&0x8000)==0) ngood++;
620 if (fIndex[i]==-1) undeff++;
621 if (nall==range &&undeff<range/2) density[i-range/2] = Float_t(ngood)/Float_t(nall-undeff);
622 }
623 Float_t maxdens=0;
624 Int_t indexmax =0;
625 for (Int_t i=0;i<160;i++){
626 if (density[i]<0) continue;
627 if (density[i]>maxdens){
628 maxdens=density[i];
629 indexmax=i;
630 }
631 }
632 //
633 //max dens point
634 fPoints[3] = maxdens;
635 fPoints[1] = indexmax;
636 //
637 // last point
638 for (Int_t i=indexmax;i<160;i++){
639 if (density[i]<0) continue;
640 if (density[i]<maxdens/2.) {
641 break;
642 }
643 fPoints[2]=i;
644 }
645 //
646 // first point
647 for (Int_t i=indexmax;i>0;i--){
648 if (density[i]<0) continue;
649 if (density[i]<maxdens/2.) {
650 break;
651 }
652 fPoints[0]=i;
653 }
654 //
655}