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Protection when a nonexistent event is asked for (J.Chudoba)
[u/mrichter/AliRoot.git] / TPC / AliTPCtracker.cxx
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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
16/*
17$Log$
bdbd0f7a 18Revision 1.10 2001/05/16 14:57:25 alibrary
19New files for folders and Stack
20
9e1a0ddb 21Revision 1.9 2001/05/11 07:16:56 hristov
22Fix needed on Sun and Alpha
23
3d39dd8b 24Revision 1.8 2001/05/08 15:00:15 hristov
25Corrections for tracking in arbitrary magnenetic field. Changes towards a concept of global Alice track. Back propagation of reconstructed tracks (Yu.Belikov)
26
be9c5115 27Revision 1.5 2000/12/20 07:51:59 kowal2
28Changes suggested by Alessandra and Paolo to avoid overlapped
29data fields in encapsulated classes.
30
d4cf1daa 31Revision 1.4 2000/11/02 07:27:16 kowal2
32code corrections
33
98ab53f4 34Revision 1.2 2000/06/30 12:07:50 kowal2
35Updated from the TPC-PreRelease branch
36
73042f01 37Revision 1.1.2.1 2000/06/25 08:53:55 kowal2
38Splitted from AliTPCtracking
39
40*/
41
42//-------------------------------------------------------
43// Implementation of the TPC tracker
44//
45// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
46//-------------------------------------------------------
47
73042f01 48#include <TObjArray.h>
49#include <TFile.h>
be5b9287 50#include <TTree.h>
51#include <iostream.h>
52
53#include "AliTPCtracker.h"
54#include "AliTPCcluster.h"
b9de75e1 55#include "AliTPCParam.h"
73042f01 56#include "AliTPCClustersRow.h"
57
b9de75e1 58//_____________________________________________________________________________
59AliTPCtracker::AliTPCtracker(const AliTPCParam *par):
60fkNIS(par->GetNInnerSector()/2),
61fkNOS(par->GetNOuterSector()/2)
62{
63 //---------------------------------------------------------------------
64 // The main TPC tracker constructor
65 //---------------------------------------------------------------------
66 fInnerSec=new AliTPCSector[fkNIS];
67 fOuterSec=new AliTPCSector[fkNOS];
68
69 Int_t i;
70 for (i=0; i<fkNIS; i++) fInnerSec[i].Setup(par,0);
71 for (i=0; i<fkNOS; i++) fOuterSec[i].Setup(par,1);
72
73 fN=0; fSectors=0;
74
75 fClustersArray.Setup(par);
76 fClustersArray.SetClusterType("AliTPCcluster");
77 fClustersArray.ConnectTree("Segment Tree");
78
79 fSeeds=0;
80}
81
82//_____________________________________________________________________________
83AliTPCtracker::~AliTPCtracker() {
84 //------------------------------------------------------------------
85 // TPC tracker destructor
86 //------------------------------------------------------------------
87 delete[] fInnerSec;
88 delete[] fOuterSec;
89 delete fSeeds;
90}
73042f01 91
92//_____________________________________________________________________________
93Double_t SigmaY2(Double_t r, Double_t tgl, Double_t pt)
94{
95 //
96 // Parametrised error of the cluster reconstruction (pad direction)
97 //
98 // Sigma rphi
99 const Float_t kArphi=0.41818e-2;
100 const Float_t kBrphi=0.17460e-4;
101 const Float_t kCrphi=0.30993e-2;
102 const Float_t kDrphi=0.41061e-3;
103
104 pt=TMath::Abs(pt)*1000.;
105 Double_t x=r/pt;
106 tgl=TMath::Abs(tgl);
107 Double_t s=kArphi - kBrphi*r*tgl + kCrphi*x*x + kDrphi*x;
108 if (s<0.4e-3) s=0.4e-3;
109 s*=1.3; //Iouri Belikov
110
111 return s;
112}
113
114//_____________________________________________________________________________
115Double_t SigmaZ2(Double_t r, Double_t tgl)
116{
117 //
118 // Parametrised error of the cluster reconstruction (drift direction)
119 //
120 // Sigma z
121 const Float_t kAz=0.39614e-2;
122 const Float_t kBz=0.22443e-4;
123 const Float_t kCz=0.51504e-1;
124
125
126 tgl=TMath::Abs(tgl);
127 Double_t s=kAz - kBz*r*tgl + kCz*tgl*tgl;
128 if (s<0.4e-3) s=0.4e-3;
129 s*=1.3; //Iouri Belikov
130
131 return s;
132}
133
134//_____________________________________________________________________________
bdbd0f7a 135Double_t f1(Double_t x1,Double_t y1,
73042f01 136 Double_t x2,Double_t y2,
137 Double_t x3,Double_t y3)
138{
139 //-----------------------------------------------------------------
140 // Initial approximation of the track curvature
141 //-----------------------------------------------------------------
142 Double_t d=(x2-x1)*(y3-y2)-(x3-x2)*(y2-y1);
143 Double_t a=0.5*((y3-y2)*(y2*y2-y1*y1+x2*x2-x1*x1)-
144 (y2-y1)*(y3*y3-y2*y2+x3*x3-x2*x2));
145 Double_t b=0.5*((x2-x1)*(y3*y3-y2*y2+x3*x3-x2*x2)-
146 (x3-x2)*(y2*y2-y1*y1+x2*x2-x1*x1));
147
148 Double_t xr=TMath::Abs(d/(d*x1-a)), yr=d/(d*y1-b);
149
150 return -xr*yr/sqrt(xr*xr+yr*yr);
151}
152
153
154//_____________________________________________________________________________
bdbd0f7a 155Double_t f2(Double_t x1,Double_t y1,
73042f01 156 Double_t x2,Double_t y2,
157 Double_t x3,Double_t y3)
158{
159 //-----------------------------------------------------------------
160 // Initial approximation of the track curvature times center of curvature
161 //-----------------------------------------------------------------
162 Double_t d=(x2-x1)*(y3-y2)-(x3-x2)*(y2-y1);
163 Double_t a=0.5*((y3-y2)*(y2*y2-y1*y1+x2*x2-x1*x1)-
164 (y2-y1)*(y3*y3-y2*y2+x3*x3-x2*x2));
165 Double_t b=0.5*((x2-x1)*(y3*y3-y2*y2+x3*x3-x2*x2)-
166 (x3-x2)*(y2*y2-y1*y1+x2*x2-x1*x1));
167
168 Double_t xr=TMath::Abs(d/(d*x1-a)), yr=d/(d*y1-b);
169
170 return -a/(d*y1-b)*xr/sqrt(xr*xr+yr*yr);
171}
172
173//_____________________________________________________________________________
bdbd0f7a 174Double_t f3(Double_t x1,Double_t y1,
73042f01 175 Double_t x2,Double_t y2,
176 Double_t z1,Double_t z2)
177{
178 //-----------------------------------------------------------------
179 // Initial approximation of the tangent of the track dip angle
180 //-----------------------------------------------------------------
181 return (z1 - z2)/sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
182}
183
184//_____________________________________________________________________________
b9de75e1 185void AliTPCtracker::LoadOuterSectors() {
186 //-----------------------------------------------------------------
187 // This function fills outer TPC sectors with clusters.
188 //-----------------------------------------------------------------
189 UInt_t index;
190 Int_t j=Int_t(fClustersArray.GetTree()->GetEntries());
191 for (Int_t i=0; i<j; i++) {
192 AliSegmentID *s=fClustersArray.LoadEntry(i);
193 Int_t sec,row;
194 AliTPCParam *par=(AliTPCParam*)fClustersArray.GetParam();
195 par->AdjustSectorRow(s->GetID(),sec,row);
196 if (sec<fkNIS*2) continue;
197 AliTPCClustersRow *clrow=fClustersArray.GetRow(sec,row);
198 Int_t ncl=clrow->GetArray()->GetEntriesFast();
199 while (ncl--) {
200 AliTPCcluster *c=(AliTPCcluster*)(*clrow)[ncl];
201 index=(((sec<<8)+row)<<16)+ncl;
202 fOuterSec[(sec-fkNIS*2)%fkNOS][row].InsertCluster(c,index);
203 }
204 }
205
206 fN=fkNOS;
207 fSectors=fOuterSec;
208}
209
210//_____________________________________________________________________________
211void AliTPCtracker::UnloadOuterSectors() {
212 //-----------------------------------------------------------------
213 // This function clears outer TPC sectors.
214 //-----------------------------------------------------------------
215 Int_t nup=fOuterSec->GetNRows();
216 for (Int_t i=0; i<fkNOS; i++) {
217 for (Int_t j=0; j<nup; j++) {
218 if (fClustersArray.GetRow(i+fkNIS*2,j))
219 fClustersArray.ClearRow(i+fkNIS*2,j);
220 if (fClustersArray.GetRow(i+fkNIS*2+fkNOS,j))
221 fClustersArray.ClearRow(i+fkNIS*2+fkNOS,j);
222 }
223 }
224
225 fN=0;
226 fSectors=0;
227}
228
229//_____________________________________________________________________________
230void AliTPCtracker::LoadInnerSectors() {
231 //-----------------------------------------------------------------
232 // This function fills inner TPC sectors with clusters.
233 //-----------------------------------------------------------------
234 UInt_t index;
235 Int_t j=Int_t(fClustersArray.GetTree()->GetEntries());
236 for (Int_t i=0; i<j; i++) {
237 AliSegmentID *s=fClustersArray.LoadEntry(i);
238 Int_t sec,row;
239 AliTPCParam *par=(AliTPCParam*)fClustersArray.GetParam();
240 par->AdjustSectorRow(s->GetID(),sec,row);
241 if (sec>=fkNIS*2) continue;
242 AliTPCClustersRow *clrow=fClustersArray.GetRow(sec,row);
243 Int_t ncl=clrow->GetArray()->GetEntriesFast();
244 while (ncl--) {
245 AliTPCcluster *c=(AliTPCcluster*)(*clrow)[ncl];
246 index=(((sec<<8)+row)<<16)+ncl;
247 fInnerSec[sec%fkNIS][row].InsertCluster(c,index);
248 }
249 }
250
251 fN=fkNIS;
252 fSectors=fInnerSec;
253}
254
255//_____________________________________________________________________________
256void AliTPCtracker::UnloadInnerSectors() {
257 //-----------------------------------------------------------------
258 // This function clears inner TPC sectors.
259 //-----------------------------------------------------------------
260 Int_t nlow=fInnerSec->GetNRows();
261 for (Int_t i=0; i<fkNIS; i++) {
262 for (Int_t j=0; j<nlow; j++) {
263 if (fClustersArray.GetRow(i,j)) fClustersArray.ClearRow(i,j);
264 if (fClustersArray.GetRow(i+fkNIS,j)) fClustersArray.ClearRow(i+fkNIS,j);
265 }
266 }
267
268 fN=0;
269 fSectors=0;
270}
271
272//_____________________________________________________________________________
273Int_t AliTPCtracker::FollowProlongation(AliTPCseed& t, Int_t rf) {
73042f01 274 //-----------------------------------------------------------------
275 // This function tries to find a track prolongation.
276 //-----------------------------------------------------------------
b9de75e1 277 Double_t xt=t.GetX();
278 const Int_t kSKIP=(t.GetNumberOfClusters()<10) ? kRowsToSkip :
279 Int_t(0.5*fSectors->GetNRows());
73042f01 280 Int_t tryAgain=kSKIP;
73042f01 281
b9de75e1 282 Double_t alpha=t.GetAlpha() - fSectors->GetAlphaShift();
283 if (alpha > 2.*TMath::Pi()) alpha -= 2.*TMath::Pi();
284 if (alpha < 0. ) alpha += 2.*TMath::Pi();
285 Int_t s=Int_t(alpha/fSectors->GetAlpha())%fN;
286
287 for (Int_t nr=fSectors->GetRowNumber(xt)-1; nr>=rf; nr--) {
288 Double_t x=fSectors->GetX(nr), ymax=fSectors->GetMaxY(nr);
73042f01 289 if (!t.PropagateTo(x)) return 0;
290
291 AliTPCcluster *cl=0;
292 UInt_t index=0;
b9de75e1 293 Double_t maxchi2=kMaxCHI2;
294 const AliTPCRow &krow=fSectors[s][nr];
295 Double_t pt=t.GetConvConst()/(100/0.299792458/0.2)/t.Get1Pt();
296 Double_t sy2=SigmaY2(t.GetX(),t.GetTgl(),pt);
73042f01 297 Double_t sz2=SigmaZ2(t.GetX(),t.GetTgl());
298 Double_t road=4.*sqrt(t.GetSigmaY2() + sy2), y=t.GetY(), z=t.GetZ();
299
b9de75e1 300 if (road>kMaxROAD) {
73042f01 301 if (t.GetNumberOfClusters()>4)
302 cerr<<t.GetNumberOfClusters()
303 <<"FindProlongation warning: Too broad road !\n";
304 return 0;
305 }
306
307 if (krow) {
308 for (Int_t i=krow.Find(y-road); i<krow; i++) {
be5b9287 309 AliTPCcluster *c=(AliTPCcluster*)(krow[i]);
73042f01 310 if (c->GetY() > y+road) break;
311 if (c->IsUsed()) continue;
312 if ((c->GetZ()-z)*(c->GetZ()-z) > 16.*(t.GetSigmaZ2()+sz2)) continue;
313 Double_t chi2=t.GetPredictedChi2(c);
314 if (chi2 > maxchi2) continue;
315 maxchi2=chi2;
316 cl=c;
317 index=krow.GetIndex(i);
318 }
319 }
320 if (cl) {
b9de75e1 321 Float_t l=fSectors->GetPadPitchWidth();
73042f01 322 t.SetSampledEdx(cl->GetQ()/l,t.GetNumberOfClusters());
be9c5115 323 if (!t.Update(cl,maxchi2,index)) {
324 if (!tryAgain--) return 0;
325 } else tryAgain=kSKIP;
73042f01 326 } else {
327 if (tryAgain==0) break;
328 if (y > ymax) {
b9de75e1 329 s = (s+1) % fN;
330 if (!t.Rotate(fSectors->GetAlpha())) return 0;
73042f01 331 } else if (y <-ymax) {
b9de75e1 332 s = (s-1+fN) % fN;
333 if (!t.Rotate(-fSectors->GetAlpha())) return 0;
73042f01 334 }
335 tryAgain--;
336 }
337 }
338
339 return 1;
b9de75e1 340}
341
342//_____________________________________________________________________________
343Int_t AliTPCtracker::FollowBackProlongation
344(AliTPCseed& seed, const AliTPCtrack &track) {
345 //-----------------------------------------------------------------
346 // This function propagates tracks back through the TPC
347 //-----------------------------------------------------------------
348 Double_t alpha=seed.GetAlpha() - fSectors->GetAlphaShift();
349 if (alpha > 2.*TMath::Pi()) alpha -= 2.*TMath::Pi();
350 if (alpha < 0. ) alpha += 2.*TMath::Pi();
351 Int_t s=Int_t(alpha/fSectors->GetAlpha())%fN;
352
353 Int_t idx=-1, sec=-1, row=-1;
354 Int_t nc=seed.GetLabel(); //index of the cluster to start with
355 if (nc--) {
356 idx=track.GetClusterIndex(nc);
357 sec=(idx&0xff000000)>>24; row=(idx&0x00ff0000)>>16;
358 }
359 if (fSectors==fInnerSec) { if (sec >= 2*fkNIS) row=-1; }
360 else { if (sec < 2*fkNIS) row=-1; }
361
362 Int_t nr=fSectors->GetNRows();
363 for (Int_t i=0; i<nr; i++) {
364 Double_t x=fSectors->GetX(i), ymax=fSectors->GetMaxY(i);
365
366 if (!seed.PropagateTo(x)) return 0;
367
368 Double_t y=seed.GetY();
369 if (y > ymax) {
370 s = (s+1) % fN;
371 if (!seed.Rotate(fSectors->GetAlpha())) return 0;
372 } else if (y <-ymax) {
373 s = (s-1+fN) % fN;
374 if (!seed.Rotate(-fSectors->GetAlpha())) return 0;
375 }
376
377 AliTPCcluster *cl=0;
378 Int_t index=0;
379 Double_t maxchi2=kMaxCHI2;
380 Double_t pt=seed.GetConvConst()/(100/0.299792458/0.2)/seed.Get1Pt();
381 Double_t sy2=SigmaY2(seed.GetX(),seed.GetTgl(),pt);
382 Double_t sz2=SigmaZ2(seed.GetX(),seed.GetTgl());
383 Double_t road=4.*sqrt(seed.GetSigmaY2() + sy2), z=seed.GetZ();
384 if (road>kMaxROAD) {
385 cerr<<seed.GetNumberOfClusters()
386 <<"AliTPCtracker::FollowBackProlongation: Too broad road !\n";
387 return 0;
388 }
389
390
391 Int_t accepted=seed.GetNumberOfClusters();
392 if (row==i) {
393 //try to accept already found cluster
394 AliTPCcluster *c=(AliTPCcluster*)GetCluster(idx);
395 Double_t chi2;
396 if ((chi2=seed.GetPredictedChi2(c))<maxchi2 || accepted<27) {
397 index=idx; cl=c; maxchi2=chi2;
398 } //else cerr<<"AliTPCtracker::FollowBackProlongation: oulier !\n";
399
400 if (nc--) {
401 idx=track.GetClusterIndex(nc);
402 sec=(idx&0xff000000)>>24; row=(idx&0x00ff0000)>>16;
403 }
404 if (fSectors==fInnerSec) { if (sec >= 2*fkNIS) row=-1; }
405 else { if (sec < 2*fkNIS) row=-1; }
73042f01 406
b9de75e1 407 }
408 if (!cl) {
409 //try to fill the gap
410 const AliTPCRow &krow=fSectors[s][i];
411 if (accepted>27)
412 if (krow) {
413 for (Int_t i=krow.Find(y-road); i<krow; i++) {
414 AliTPCcluster *c=(AliTPCcluster*)(krow[i]);
415 if (c->GetY() > y+road) break;
416 if (c->IsUsed()) continue;
417 if ((c->GetZ()-z)*(c->GetZ()-z)>16.*(seed.GetSigmaZ2()+sz2)) continue;
418 Double_t chi2=seed.GetPredictedChi2(c);
419 if (chi2 > maxchi2) continue;
420 maxchi2=chi2;
421 cl=c;
422 index=krow.GetIndex(i);
423 }
424 }
425 }
426
427 if (cl) {
428 Float_t l=fSectors->GetPadPitchWidth();
429 seed.SetSampledEdx(cl->GetQ()/l,seed.GetNumberOfClusters());
430 seed.Update(cl,maxchi2,index);
431 }
432
433 }
434
435 seed.SetLabel(nc);
436
437 return 1;
73042f01 438}
439
440//_____________________________________________________________________________
b9de75e1 441void AliTPCtracker::MakeSeeds(Int_t i1, Int_t i2) {
73042f01 442 //-----------------------------------------------------------------
443 // This function creates track seeds.
444 //-----------------------------------------------------------------
b9de75e1 445 if (fSeeds==0) fSeeds=new TObjArray(15000);
446
73042f01 447 Double_t x[5], c[15];
448
b9de75e1 449 Double_t alpha=fOuterSec->GetAlpha(), shift=fOuterSec->GetAlphaShift();
73042f01 450 Double_t cs=cos(alpha), sn=sin(alpha);
451
b9de75e1 452 Double_t x1 =fOuterSec->GetX(i1);
453 Double_t xx2=fOuterSec->GetX(i2);
73042f01 454
b9de75e1 455 for (Int_t ns=0; ns<fkNOS; ns++) {
456 Int_t nl=fOuterSec[(ns-1+fkNOS)%fkNOS][i2];
457 Int_t nm=fOuterSec[ns][i2];
458 Int_t nu=fOuterSec[(ns+1)%fkNOS][i2];
459 const AliTPCRow& kr1=fOuterSec[ns][i1];
73042f01 460 for (Int_t is=0; is < kr1; is++) {
461 Double_t y1=kr1[is]->GetY(), z1=kr1[is]->GetZ();
462 for (Int_t js=0; js < nl+nm+nu; js++) {
463 const AliTPCcluster *kcl;
464 Double_t x2, y2, z2;
465 Double_t x3=0.,y3=0.;
466
467 if (js<nl) {
b9de75e1 468 const AliTPCRow& kr2=fOuterSec[(ns-1+fkNOS)%fkNOS][i2];
73042f01 469 kcl=kr2[js];
470 y2=kcl->GetY(); z2=kcl->GetZ();
471 x2= xx2*cs+y2*sn;
472 y2=-xx2*sn+y2*cs;
473 } else
474 if (js<nl+nm) {
b9de75e1 475 const AliTPCRow& kr2=fOuterSec[ns][i2];
73042f01 476 kcl=kr2[js-nl];
477 x2=xx2; y2=kcl->GetY(); z2=kcl->GetZ();
478 } else {
b9de75e1 479 const AliTPCRow& kr2=fOuterSec[(ns+1)%fkNOS][i2];
73042f01 480 kcl=kr2[js-nl-nm];
481 y2=kcl->GetY(); z2=kcl->GetZ();
482 x2=xx2*cs-y2*sn;
483 y2=xx2*sn+y2*cs;
484 }
485
486 Double_t zz=z1 - z1/x1*(x1-x2);
487 if (TMath::Abs(zz-z2)>5.) continue;
488
489 Double_t d=(x2-x1)*(0.-y2)-(0.-x2)*(y2-y1);
490 if (d==0.) {cerr<<"MakeSeeds warning: Straight seed !\n"; continue;}
491
492 x[0]=y1;
493 x[1]=z1;
b9de75e1 494 x[4]=f1(x1,y1,x2,y2,x3,y3);
495 if (TMath::Abs(x[4]) >= 0.0066) continue;
be5b9287 496 x[2]=f2(x1,y1,x2,y2,x3,y3);
b9de75e1 497 //if (TMath::Abs(x[4]*x1-x[2]) >= 0.99999) continue;
498 x[3]=f3(x1,y1,x2,y2,z1,z2);
499 if (TMath::Abs(x[3]) > 1.2) continue;
be5b9287 500 Double_t a=asin(x[2]);
b9de75e1 501 Double_t zv=z1 - x[3]/x[4]*(a+asin(x[4]*x1-x[2]));
73042f01 502 if (TMath::Abs(zv)>10.) continue;
503
504 Double_t sy1=kr1[is]->GetSigmaY2(), sz1=kr1[is]->GetSigmaZ2();
505 Double_t sy2=kcl->GetSigmaY2(), sz2=kcl->GetSigmaZ2();
506 Double_t sy3=100*0.025, sy=0.1, sz=0.1;
507
b9de75e1 508 Double_t f40=(f1(x1,y1+sy,x2,y2,x3,y3)-x[4])/sy;
509 Double_t f42=(f1(x1,y1,x2,y2+sy,x3,y3)-x[4])/sy;
510 Double_t f43=(f1(x1,y1,x2,y2,x3,y3+sy)-x[4])/sy;
be5b9287 511 Double_t f20=(f2(x1,y1+sy,x2,y2,x3,y3)-x[2])/sy;
512 Double_t f22=(f2(x1,y1,x2,y2+sy,x3,y3)-x[2])/sy;
b9de75e1 513 Double_t f23=(f2(x1,y1,x2,y2,x3,y3+sy)-x[2])/sy;
514 Double_t f30=(f3(x1,y1+sy,x2,y2,z1,z2)-x[3])/sy;
515 Double_t f31=(f3(x1,y1,x2,y2,z1+sz,z2)-x[3])/sz;
516 Double_t f32=(f3(x1,y1,x2,y2+sy,z1,z2)-x[3])/sy;
517 Double_t f34=(f3(x1,y1,x2,y2,z1,z2+sz)-x[3])/sz;
73042f01 518
519 c[0]=sy1;
520 c[1]=0.; c[2]=sz1;
b9de75e1 521 c[3]=f20*sy1; c[4]=0.; c[5]=f20*sy1*f20+f22*sy2*f22+f23*sy3*f23;
522 c[6]=f30*sy1; c[7]=f31*sz1; c[8]=f30*sy1*f20+f32*sy2*f22;
523 c[9]=f30*sy1*f30+f31*sz1*f31+f32*sy2*f32+f34*sz2*f34;
524 c[10]=f40*sy1; c[11]=0.; c[12]=f40*sy1*f20+f42*sy2*f22+f43*sy3*f23;
525 c[13]=f30*sy1*f40+f32*sy2*f42;
526 c[14]=f40*sy1*f40+f42*sy2*f42+f43*sy3*f43;
73042f01 527
528 UInt_t index=kr1.GetIndex(is);
529 AliTPCseed *track=new AliTPCseed(index, x, c, x1, ns*alpha+shift);
b9de75e1 530 Float_t l=fOuterSec->GetPadPitchWidth();
73042f01 531 track->SetSampledEdx(kr1[is]->GetQ()/l,0);
532
b9de75e1 533 Int_t rc=FollowProlongation(*track, i2);
be9c5115 534 if (rc==0 || track->GetNumberOfClusters()<(i1-i2)/2) delete track;
b9de75e1 535 else fSeeds->AddLast(track);
73042f01 536 }
537 }
538 }
539}
540
541//_____________________________________________________________________________
b9de75e1 542Int_t AliTPCtracker::ReadSeeds(const TFile *inp) {
73042f01 543 //-----------------------------------------------------------------
b9de75e1 544 // This function reades track seeds.
73042f01 545 //-----------------------------------------------------------------
546 TDirectory *savedir=gDirectory;
547
b9de75e1 548 TFile *in=(TFile*)inp;
549 if (!in->IsOpen()) {
550 cerr<<"AliTPCtracker::ReadSeeds(): input file is not open !\n";
be5b9287 551 return 1;
73042f01 552 }
553
b9de75e1 554 in->cd();
555 TTree *seedTree=(TTree*)in->Get("Seeds");
556 if (!seedTree) {
557 cerr<<"AliTPCtracker::ReadSeeds(): ";
558 cerr<<"can't get a tree with track seeds !\n";
559 return 2;
560 }
561 AliTPCtrack *seed=new AliTPCtrack;
562 seedTree->SetBranchAddress("tracks",&seed);
563
564 if (fSeeds==0) fSeeds=new TObjArray(15000);
73042f01 565
b9de75e1 566 Int_t n=(Int_t)seedTree->GetEntries();
567 for (Int_t i=0; i<n; i++) {
568 seedTree->GetEvent(i);
569 fSeeds->AddLast(new AliTPCseed(*seed,seed->GetAlpha()));
570 }
571
572 delete seed;
573 savedir->cd();
73042f01 574
b9de75e1 575 return 0;
576}
73042f01 577
b9de75e1 578//_____________________________________________________________________________
579Int_t AliTPCtracker::Clusters2Tracks(const TFile *inp, TFile *out) {
580 //-----------------------------------------------------------------
581 // This is a track finder.
582 //-----------------------------------------------------------------
583 TDirectory *savedir=gDirectory;
73042f01 584
b9de75e1 585 if (inp) {
586 TFile *in=(TFile*)inp;
587 if (!in->IsOpen()) {
588 cerr<<"AliTPCtracker::Clusters2Tracks(): input file is not open !\n";
589 return 1;
590 }
591 }
73042f01 592
b9de75e1 593 if (!out->IsOpen()) {
594 cerr<<"AliTPCtracker::Clusters2Tracks(): output file is not open !\n";
595 return 2;
73042f01 596 }
597
b9de75e1 598 out->cd();
599 TTree tracktree("TPCf","Tree with TPC tracks");
600 AliTPCtrack *iotrack=0;
601 tracktree.Branch("tracks","AliTPCtrack",&iotrack,32000,0);
602
603 LoadOuterSectors();
604
73042f01 605 //find track seeds
b9de75e1 606 Int_t nup=fOuterSec->GetNRows(), nlow=fInnerSec->GetNRows();
73042f01 607 Int_t nrows=nlow+nup;
b9de75e1 608 if (fSeeds==0) {
609 Int_t gap=Int_t(0.125*nrows), shift=Int_t(0.5*gap);
610 MakeSeeds(nup-1, nup-1-gap);
611 MakeSeeds(nup-1-shift, nup-1-shift-gap);
612 }
613 fSeeds->Sort();
73042f01 614
615 //tracking in outer sectors
b9de75e1 616 Int_t nseed=fSeeds->GetEntriesFast();
617 Int_t i;
73042f01 618 for (i=0; i<nseed; i++) {
b9de75e1 619 AliTPCseed *pt=(AliTPCseed*)fSeeds->UncheckedAt(i), &t=*pt;
620 if (FollowProlongation(t)) {
621 UseClusters(&t);
73042f01 622 continue;
623 }
b9de75e1 624 delete fSeeds->RemoveAt(i);
73042f01 625 }
b9de75e1 626 UnloadOuterSectors();
73042f01 627
628 //tracking in inner sectors
b9de75e1 629 LoadInnerSectors();
73042f01 630 Int_t found=0;
631 for (i=0; i<nseed; i++) {
b9de75e1 632 AliTPCseed *pt=(AliTPCseed*)fSeeds->UncheckedAt(i), &t=*pt;
73042f01 633 if (!pt) continue;
634 Int_t nc=t.GetNumberOfClusters();
635
b9de75e1 636 Double_t alpha=t.GetAlpha() - fInnerSec->GetAlphaShift();
73042f01 637 if (alpha > 2.*TMath::Pi()) alpha -= 2.*TMath::Pi();
638 if (alpha < 0. ) alpha += 2.*TMath::Pi();
b9de75e1 639 Int_t ns=Int_t(alpha/fInnerSec->GetAlpha())%fkNIS;
73042f01 640
b9de75e1 641 alpha=ns*fInnerSec->GetAlpha() + fInnerSec->GetAlphaShift() - t.GetAlpha();
73042f01 642
643 if (t.Rotate(alpha)) {
b9de75e1 644 if (FollowProlongation(t)) {
73042f01 645 if (t.GetNumberOfClusters() >= Int_t(0.4*nrows)) {
646 t.CookdEdx();
73042f01 647 iotrack=pt;
648 tracktree.Fill();
b9de75e1 649 UseClusters(&t,nc);
650 cerr<<found++<<'\r';
73042f01 651 }
652 }
653 }
b9de75e1 654 delete fSeeds->RemoveAt(i);
73042f01 655 }
b9de75e1 656 UnloadInnerSectors();
657
73042f01 658 tracktree.Write();
659
b9de75e1 660 cerr<<"Number of found tracks : "<<found<<endl;
661
662 savedir->cd();
663
664 return 0;
665}
666
667//_____________________________________________________________________________
668Int_t AliTPCtracker::PropagateBack(const TFile *inp, TFile *out) {
669 //-----------------------------------------------------------------
670 // This function propagates tracks back through the TPC.
671 //-----------------------------------------------------------------
672 fSeeds=new TObjArray(15000);
673
674 TFile *in=(TFile*)inp;
675 TDirectory *savedir=gDirectory;
676
677 if (!in->IsOpen()) {
678 cerr<<"AliTPCtracker::PropagateBack(): ";
679 cerr<<"file with back propagated ITS tracks is not open !\n";
680 return 1;
73042f01 681 }
682
b9de75e1 683 if (!out->IsOpen()) {
684 cerr<<"AliTPCtracker::PropagateBack(): ";
685 cerr<<"file for back propagated TPC tracks is not open !\n";
686 return 2;
687 }
688
689 in->cd();
690 TTree *bckTree=(TTree*)in->Get("ITSb");
691 if (!bckTree) {
692 cerr<<"AliTPCtracker::PropagateBack() ";
693 cerr<<"can't get a tree with back propagated ITS tracks !\n";
694 return 3;
695 }
696 AliTPCtrack *bckTrack=new AliTPCtrack;
697 bckTree->SetBranchAddress("tracks",&bckTrack);
698
699 TTree *tpcTree=(TTree*)in->Get("TPCf");
700 if (!tpcTree) {
701 cerr<<"AliTPCtracker::PropagateBack() ";
702 cerr<<"can't get a tree with TPC tracks !\n";
703 return 4;
704 }
705 AliTPCtrack *tpcTrack=new AliTPCtrack;
706 tpcTree->SetBranchAddress("tracks",&tpcTrack);
707
708//*** Prepare an array of tracks to be back propagated
709 Int_t nup=fOuterSec->GetNRows(), nlow=fInnerSec->GetNRows();
710 Int_t nrows=nlow+nup;
711
712 TObjArray tracks(15000);
713 Int_t i=0,j=0;
714 Int_t tpcN=(Int_t)tpcTree->GetEntries();
715 Int_t bckN=(Int_t)bckTree->GetEntries();
716 if (j<bckN) bckTree->GetEvent(j++);
717 for (i=0; i<tpcN; i++) {
718 tpcTree->GetEvent(i);
719 Double_t alpha=tpcTrack->GetAlpha();
720 if (j<bckN &&
721 TMath::Abs(tpcTrack->GetLabel())==TMath::Abs(bckTrack->GetLabel())) {
722 if (!bckTrack->Rotate(alpha-bckTrack->GetAlpha())) continue;
723 fSeeds->AddLast(new AliTPCseed(*bckTrack,bckTrack->GetAlpha()));
724 bckTree->GetEvent(j++);
725 } else {
726 tpcTrack->ResetCovariance();
727 fSeeds->AddLast(new AliTPCseed(*tpcTrack,alpha));
728 }
729 tracks.AddLast(new AliTPCtrack(*tpcTrack));
730 }
731
732 out->cd();
733 TTree backTree("TPCb","Tree with back propagated TPC tracks");
734 AliTPCtrack *otrack=0;
735 backTree.Branch("tracks","AliTPCtrack",&otrack,32000,0);
736
737//*** Back propagation through inner sectors
738 LoadInnerSectors();
739 Int_t nseed=fSeeds->GetEntriesFast();
740 for (i=0; i<nseed; i++) {
741 AliTPCseed *ps=(AliTPCseed*)fSeeds->UncheckedAt(i), &s=*ps;
742 const AliTPCtrack *pt=(AliTPCtrack*)tracks.UncheckedAt(i), &t=*pt;
73042f01 743
b9de75e1 744 Int_t nc=t.GetNumberOfClusters();
745 s.SetLabel(nc-1); //set number of the cluster to start with
73042f01 746
b9de75e1 747 if (FollowBackProlongation(s,t)) {
748 UseClusters(&s);
749 continue;
750 }
751 delete fSeeds->RemoveAt(i);
752 }
753 UnloadInnerSectors();
754
755//*** Back propagation through outer sectors
756 LoadOuterSectors();
757 Int_t found=0;
758 for (i=0; i<nseed; i++) {
759 AliTPCseed *ps=(AliTPCseed*)fSeeds->UncheckedAt(i), &s=*ps;
760 if (!ps) continue;
761 Int_t nc=s.GetNumberOfClusters();
762 const AliTPCtrack *pt=(AliTPCtrack*)tracks.UncheckedAt(i), &t=*pt;
763
764 Double_t alpha=s.GetAlpha() - fSectors->GetAlphaShift();
765 if (alpha > 2.*TMath::Pi()) alpha -= 2.*TMath::Pi();
766 if (alpha < 0. ) alpha += 2.*TMath::Pi();
767 Int_t ns=Int_t(alpha/fSectors->GetAlpha())%fN;
768
769 alpha =ns*fSectors->GetAlpha() + fSectors->GetAlphaShift();
770 alpha-=s.GetAlpha();
771
772 if (s.Rotate(alpha)) {
773 if (FollowBackProlongation(s,t)) {
774 if (s.GetNumberOfClusters() >= Int_t(0.4*nrows)) {
775 s.CookdEdx();
776 s.SetLabel(t.GetLabel());
777 UseClusters(&s,nc);
778 otrack=ps;
779 backTree.Fill();
780 cerr<<found++<<'\r';
781 continue;
782 }
783 }
784 }
785 delete fSeeds->RemoveAt(i);
786 }
787 UnloadOuterSectors();
788
789 backTree.Write();
73042f01 790 savedir->cd();
b9de75e1 791 cerr<<"Number of seeds: "<<nseed<<endl;
792 cerr<<"Number of back propagated ITS tracks: "<<bckN<<endl;
793 cerr<<"Number of back propagated TPC tracks: "<<found<<endl;
794
795 delete bckTrack;
796 delete tpcTrack;
be5b9287 797
798 return 0;
73042f01 799}
800
b9de75e1 801//_________________________________________________________________________
802AliCluster *AliTPCtracker::GetCluster(Int_t index) const {
803 //--------------------------------------------------------------------
804 // Return pointer to a given cluster
805 //--------------------------------------------------------------------
806 Int_t sec=(index&0xff000000)>>24;
807 Int_t row=(index&0x00ff0000)>>16;
808 Int_t ncl=(index&0x0000ffff)>>00;
809
9e1a0ddb 810 AliTPCClustersRow *clrow=((AliTPCtracker *) this)->fClustersArray.GetRow(sec,row);
b9de75e1 811 return (AliCluster*)(*clrow)[ncl];
812}
813
814//__________________________________________________________________________
815void AliTPCtracker::CookLabel(AliKalmanTrack *t, Float_t wrong) const {
816 //--------------------------------------------------------------------
817 //This function "cooks" a track label. If label<0, this track is fake.
818 //--------------------------------------------------------------------
819 Int_t noc=t->GetNumberOfClusters();
820 Int_t *lb=new Int_t[noc];
821 Int_t *mx=new Int_t[noc];
822 AliCluster **clusters=new AliCluster*[noc];
823
824 Int_t i;
825 for (i=0; i<noc; i++) {
826 lb[i]=mx[i]=0;
827 Int_t index=t->GetClusterIndex(i);
828 clusters[i]=GetCluster(index);
829 }
830
831 Int_t lab=123456789;
832 for (i=0; i<noc; i++) {
833 AliCluster *c=clusters[i];
834 lab=TMath::Abs(c->GetLabel(0));
835 Int_t j;
836 for (j=0; j<noc; j++) if (lb[j]==lab || mx[j]==0) break;
837 lb[j]=lab;
838 (mx[j])++;
839 }
840
841 Int_t max=0;
842 for (i=0; i<noc; i++) if (mx[i]>max) {max=mx[i]; lab=lb[i];}
843
844 for (i=0; i<noc; i++) {
845 AliCluster *c=clusters[i];
846 if (TMath::Abs(c->GetLabel(1)) == lab ||
847 TMath::Abs(c->GetLabel(2)) == lab ) max++;
848 }
849
850 if ((1.- Float_t(max)/noc) > wrong) lab=-lab;
851
852 else {
853 Int_t tail=Int_t(0.10*noc);
854 max=0;
855 for (i=1; i<=tail; i++) {
856 AliCluster *c=clusters[noc-i];
857 if (lab == TMath::Abs(c->GetLabel(0)) ||
858 lab == TMath::Abs(c->GetLabel(1)) ||
859 lab == TMath::Abs(c->GetLabel(2))) max++;
860 }
861 if (max < Int_t(0.5*tail)) lab=-lab;
862 }
863
864 t->SetLabel(lab);
865
866 delete[] lb;
867 delete[] mx;
868 delete[] clusters;
869}
870
871//_________________________________________________________________________
872void AliTPCtracker::AliTPCSector::Setup(const AliTPCParam *par, Int_t f) {
873 //-----------------------------------------------------------------------
874 // Setup inner sector
875 //-----------------------------------------------------------------------
876 if (f==0) {
877 fAlpha=par->GetInnerAngle();
878 fAlphaShift=par->GetInnerAngleShift();
879 fPadPitchWidth=par->GetInnerPadPitchWidth();
880 fPadPitchLength=par->GetInnerPadPitchLength();
881
882 fN=par->GetNRowLow();
883 fRow=new AliTPCRow[fN];
884 for (Int_t i=0; i<fN; i++) fRow[i].SetX(par->GetPadRowRadiiLow(i));
885 } else {
886 fAlpha=par->GetOuterAngle();
887 fAlphaShift=par->GetOuterAngleShift();
888 fPadPitchWidth=par->GetOuterPadPitchWidth();
889 fPadPitchLength=par->GetOuterPadPitchLength();
890
891 fN=par->GetNRowUp();
892 fRow=new AliTPCRow[fN];
893 for (Int_t i=0; i<fN; i++) fRow[i].SetX(par->GetPadRowRadiiUp(i));
894 }
895}
896
73042f01 897//_________________________________________________________________________
898void
899AliTPCtracker::AliTPCRow::InsertCluster(const AliTPCcluster* c, UInt_t index) {
900 //-----------------------------------------------------------------------
901 // Insert a cluster into this pad row in accordence with its y-coordinate
902 //-----------------------------------------------------------------------
b9de75e1 903 if (fN==kMaxClusterPerRow) {
73042f01 904 cerr<<"AliTPCRow::InsertCluster(): Too many clusters !\n"; return;
905 }
906 if (fN==0) {fIndex[0]=index; fClusters[fN++]=c; return;}
907 Int_t i=Find(c->GetY());
908 memmove(fClusters+i+1 ,fClusters+i,(fN-i)*sizeof(AliTPCcluster*));
909 memmove(fIndex +i+1 ,fIndex +i,(fN-i)*sizeof(UInt_t));
910 fIndex[i]=index; fClusters[i]=c; fN++;
911}
912
913//___________________________________________________________________
914Int_t AliTPCtracker::AliTPCRow::Find(Double_t y) const {
915 //-----------------------------------------------------------------------
916 // Return the index of the nearest cluster
917 //-----------------------------------------------------------------------
918 if (y <= fClusters[0]->GetY()) return 0;
919 if (y > fClusters[fN-1]->GetY()) return fN;
920 Int_t b=0, e=fN-1, m=(b+e)/2;
921 for (; b<e; m=(b+e)/2) {
922 if (y > fClusters[m]->GetY()) b=m+1;
923 else e=m;
924 }
925 return m;
926}
927
928//_____________________________________________________________________________
929void AliTPCtracker::AliTPCseed::CookdEdx(Double_t low, Double_t up) {
930 //-----------------------------------------------------------------
931 // This funtion calculates dE/dX within the "low" and "up" cuts.
932 //-----------------------------------------------------------------
933 Int_t i;
be9c5115 934 Int_t nc=GetNumberOfClusters();
73042f01 935
936 Int_t swap;//stupid sorting
937 do {
938 swap=0;
be9c5115 939 for (i=0; i<nc-1; i++) {
d4cf1daa 940 if (fdEdxSample[i]<=fdEdxSample[i+1]) continue;
941 Float_t tmp=fdEdxSample[i];
942 fdEdxSample[i]=fdEdxSample[i+1]; fdEdxSample[i+1]=tmp;
73042f01 943 swap++;
944 }
945 } while (swap);
946
be9c5115 947 Int_t nl=Int_t(low*nc), nu=Int_t(up*nc);
73042f01 948 Float_t dedx=0;
d4cf1daa 949 for (i=nl; i<=nu; i++) dedx += fdEdxSample[i];
73042f01 950 dedx /= (nu-nl+1);
951 SetdEdx(dedx);
952}
953
73042f01 954
955