TRD/AliTRDtracker.cxx

   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 /* $Id$ */
  17
  18 ///////////////////////////////////////////////////////////////////////////////
  19 //                                                                           //
  20 //  The standard TRD tracker                                                 //
  21 //  Based on Kalman filltering approach                                      //
  22 //                                                                           //
  23 ///////////////////////////////////////////////////////////////////////////////
  24
  25 #include <Riostream.h>
  26 #include <TFile.h>
  27 #include <TBranch.h>
  28 #include <TTree.h>
  29 #include <TObjArray.h>
  30
  31 #include "AliTRDgeometry.h"
  32 #include "AliTRDpadPlane.h"
  33 #include "AliTRDgeometryFull.h"
  34 #include "AliTRDcluster.h"
  35 #include "AliTRDtrack.h"
  36 #include "AliTRDseed.h"
  37 #include "AliESD.h"
  38
  39 #include "AliTRDcalibDB.h"
  40 #include "AliTRDCommonParam.h"
  41
  42 #include "TTreeStream.h"
  43 #include "TGraph.h"
  44 #include "AliTRDtracker.h"
  45 #include "TLinearFitter.h"
  46 #include "AliRieman.h"
  47 #include "AliTrackPointArray.h"
  48 #include "AliAlignObj.h"
  49 #include "AliTRDReconstructor.h"
  50
  51 ClassImp(AliTRDtracker)
  52
  53   const  Float_t     AliTRDtracker::fgkMinClustersInTrack = 0.5;
  54   const  Float_t     AliTRDtracker::fgkLabelFraction      = 0.8;
  55   const  Double_t    AliTRDtracker::fgkMaxChi2            = 12.;
  56   const  Double_t    AliTRDtracker::fgkMaxSnp             = 0.95; // correspond to tan = 3
  57   const  Double_t    AliTRDtracker::fgkMaxStep            = 2.;   // maximal step size in propagation
  58
  59 //_____________________________________________________________________________
  60 AliTRDtracker::AliTRDtracker():AliTracker(),
  61                                fGeom(0),
  62                                fNclusters(0),
  63                                fClusters(0),
  64                                fNseeds(0),
  65                                fSeeds(0),
  66                                fNtracks(0),
  67                                fTracks(0),
  68                                fTimeBinsPerPlane(0),
  69                                fAddTRDseeds(kFALSE),
  70                                fNoTilt(kFALSE)
  71 {
  72   //
  73   // Default constructor
  74   //
  75
  76   for(Int_t i=0;i<kTrackingSectors;i++) fTrSec[i]=0;
  77   for(Int_t j=0;j<5;j++)
  78   for(Int_t k=0;k<18;k++) fHoles[j][k]=kFALSE;
  79   fDebugStreamer = 0;
  80
  81 }
  82
  83 //_____________________________________________________________________________
  84 AliTRDtracker::AliTRDtracker(const TFile *geomfile):AliTracker()
  85 {
  86   //
  87   //  Main constructor
  88   //
  89
  90   fAddTRDseeds = kFALSE;
  91   fGeom = NULL;
  92   fNoTilt = kFALSE;
  93
  94   TDirectory *savedir=gDirectory;
  95   TFile *in=(TFile*)geomfile;
  96   if (!in->IsOpen()) {
  97     printf("AliTRDtracker::AliTRDtracker(): geometry file is not open!\n");
  98     printf("    FULL TRD geometry and DEFAULT TRD parameter will be used\n");
  99   }
 100   else {
 101     in->cd();
 102     fGeom = (AliTRDgeometry*) in->Get("TRDgeometry");
 103   }
 104
 105   if(fGeom) {
 106     //    printf("Found geometry version %d on file \n", fGeom->IsVersion());
 107   }
 108   else {
 109     printf("AliTRDtracker::AliTRDtracker(): can't find TRD geometry!\n");
 110
 111     fGeom = new AliTRDgeometryFull();
 112
 113   }
 114   fGeom->ReadGeoMatrices();
 115
 116   savedir->cd();
 117
 118   fNclusters = 0;
 119   fClusters  = new TObjArray(2000);
 120   fNseeds    = 0;
 121   fSeeds     = new TObjArray(2000);
 122   fNtracks   = 0;
 123   fTracks    = new TObjArray(1000);
 124
 125   for(Int_t geomS = 0; geomS < kTrackingSectors; geomS++) {
 126     Int_t trS = CookSectorIndex(geomS);
 127     fTrSec[trS] = new AliTRDtrackingSector(fGeom, geomS);
 128     for (Int_t icham=0;icham<AliTRDgeometry::kNcham; icham++){
 129       fHoles[icham][trS]=fGeom->IsHole(0,icham,geomS);
 130     }
 131   }
 132   AliTRDpadPlane *padPlane = AliTRDCommonParam::Instance()->GetPadPlane(0,0);
 133   Float_t tiltAngle = TMath::Abs(padPlane->GetTiltingAngle());
 134   if(tiltAngle < 0.1) {
 135     fNoTilt = kTRUE;
 136   }
 137
 138   fTimeBinsPerPlane =  AliTRDcalibDB::Instance()->GetNumberOfTimeBins();
 139
 140   fDebugStreamer = new TTreeSRedirector("TRDdebug.root");
 141
 142   savedir->cd();
 143
 144 }
 145
 146 //_____________________________________________________________________________
 147 AliTRDtracker::~AliTRDtracker()
 148 {
 149   //
 150   // Destructor of AliTRDtracker
 151   //
 152
 153   if (fClusters) {
 154     fClusters->Delete();
 155     delete fClusters;
 156   }
 157   if (fTracks) {
 158     fTracks->Delete();
 159     delete fTracks;
 160   }
 161   if (fSeeds) {
 162     fSeeds->Delete();
 163     delete fSeeds;
 164   }
 165   delete fGeom;
 166
 167   for(Int_t geomS = 0; geomS < kTrackingSectors; geomS++) {
 168     delete fTrSec[geomS];
 169   }
 170   if (fDebugStreamer) {
 171     //fDebugStreamer->Close();
 172     delete fDebugStreamer;
 173   }
 174
 175 }
 176
 177 //_____________________________________________________________________________
 178 Int_t  AliTRDtracker::LocalToGlobalID(Int_t lid)
 179 {
 180   //
 181   // Transform internal TRD ID to global detector ID
 182   //
 183
 184   Int_t  isector = fGeom->GetSector(lid);
 185   Int_t  ichamber= fGeom->GetChamber(lid);
 186   Int_t  iplan   = fGeom->GetPlane(lid);
 187   //
 188   AliAlignObj::ELayerID iLayer = AliAlignObj::kTRD1;
 189   switch (iplan) {
 190   case 0:
 191     iLayer = AliAlignObj::kTRD1;
 192     break;
 193   case 1:
 194     iLayer = AliAlignObj::kTRD2;
 195     break;
 196   case 2:
 197     iLayer = AliAlignObj::kTRD3;
 198     break;
 199   case 3:
 200     iLayer = AliAlignObj::kTRD4;
 201     break;
 202   case 4:
 203     iLayer = AliAlignObj::kTRD5;
 204     break;
 205   case 5:
 206     iLayer = AliAlignObj::kTRD6;
 207     break;
 208   };
 209   Int_t modId = isector*fGeom->Ncham()+ichamber;
 210   UShort_t volid = AliAlignObj::LayerToVolUID(iLayer,modId);
 211
 212   return volid;
 213
 214 }
 215
 216 //_____________________________________________________________________________
 217 Int_t  AliTRDtracker::GlobalToLocalID(Int_t gid)
 218 {
 219   //
 220   // Transform global detector ID to local detector ID
 221   //
 222
 223   Int_t modId=0;
 224   AliAlignObj::ELayerID  layerId  = AliAlignObj::VolUIDToLayer(gid, modId);
 225   Int_t     isector  = modId/fGeom->Ncham();
 226   Int_t     ichamber = modId%fGeom->Ncham();
 227   Int_t     iLayer    = -1;
 228   switch (layerId) {
 229   case AliAlignObj::kTRD1:
 230     iLayer = 0;
 231     break;
 232   case AliAlignObj::kTRD2:
 233     iLayer = 1;
 234     break;
 235   case AliAlignObj::kTRD3:
 236     iLayer = 2;
 237     break;
 238   case AliAlignObj::kTRD4:
 239     iLayer = 3;
 240     break;
 241   case AliAlignObj::kTRD5:
 242     iLayer = 4;
 243     break;
 244   case AliAlignObj::kTRD6:
 245     iLayer = 5;
 246     break;
 247   default:
 248     iLayer =-1;
 249   }
 250   if (iLayer<0) return -1;
 251   Int_t lid = fGeom->GetDetector(iLayer,ichamber,isector);
 252
 253   return lid;
 254
 255 }
 256
 257 //_____________________________________________________________________________
 258 Bool_t  AliTRDtracker::Transform(AliTRDcluster * cluster)
 259 {
 260   //
 261   // Transform something ... whatever ...
 262   //
 263
 264   const Double_t kX0shift           = 2.52;    // magic constants for geo manager transformation
 265   const Double_t kX0shift5          = 3.05;    //
 266   //
 267   //
 268   // apply alignment and calibration to transform cluster
 269   //
 270   //
 271   Int_t detector = cluster->GetDetector();
 272   Int_t plane   = fGeom->GetPlane(cluster->GetDetector());
 273   Int_t chamber = fGeom->GetChamber(cluster->GetDetector());
 274   Int_t sector  = fGeom->GetSector(cluster->GetDetector());
 275
 276   Double_t dxAmp  = (Double_t) fGeom->CamHght();          // Amplification region
 277   Double_t driftX = TMath::Max(cluster->GetX()-dxAmp*0.5,0.);  // drift distance
 278   //
 279   // ExB correction
 280   //
 281   Double_t vdrift = AliTRDcalibDB::Instance()->GetVdrift(cluster->GetDetector(),0,0);
 282   Double_t exB =   AliTRDcalibDB::Instance()->GetOmegaTau(vdrift);
 283   //
 284   AliTRDCommonParam* commonParam = AliTRDCommonParam::Instance();
 285   AliTRDpadPlane * padPlane = commonParam->GetPadPlane(plane,chamber);
 286   Double_t zshiftIdeal  = 0.5*(padPlane->GetRow0()+padPlane->GetRowEnd());
 287   Double_t localPos[3], localPosTracker[3];
 288   localPos[0] = -cluster->GetX();
 289   localPos[1] =  cluster->GetY() - driftX*exB;
 290   localPos[2] =  cluster->GetZ() -zshiftIdeal;
 291   //
 292   cluster->SetY(cluster->GetY() - driftX*exB);
 293   Double_t xplane = (Double_t) AliTRDgeometry::GetTime0(plane);
 294   cluster->SetX(xplane- cluster->GetX());
 295   //
 296   TGeoHMatrix * matrix =  fGeom->GetCorrectionMatrix(cluster->GetDetector());
 297   if (!matrix){
 298     // no matrix found - if somebody used geometry with holes
 299     AliError("Invalid Geometry - Default Geometry used\n");
 300     return kTRUE;
 301   }
 302   matrix->LocalToMaster(localPos, localPosTracker);
 303   //
 304   //
 305   //
 306   if (AliTRDReconstructor::StreamLevel()>1){
 307     (*fDebugStreamer)<<"Transform"<<
 308       "Cl.="<<cluster<<
 309       "matrix.="<<matrix<<
 310       "Detector="<<detector<<
 311       "Sector="<<sector<<
 312       "Plane="<<plane<<
 313       "Chamber="<<chamber<<
 314       "lx0="<<localPosTracker[0]<<
 315       "ly0="<<localPosTracker[1]<<
 316       "lz0="<<localPosTracker[2]<<
 317       "\n";
 318   }
 319   //
 320   if (plane==5)
 321      cluster->SetX(localPosTracker[0]+kX0shift5);
 322   else
 323     cluster->SetX(localPosTracker[0]+kX0shift);
 324
 325   cluster->SetY(localPosTracker[1]);
 326   cluster->SetZ(localPosTracker[2]);
 327
 328   return kTRUE;
 329
 330 }
 331
 332 //_____________________________________________________________________________
 333 // Bool_t  AliTRDtracker::Transform(AliTRDcluster * cluster)
 334 //{
 335 //   //
 336 //   //
 337 //   const Double_t kDriftCorrection  = 1.01;                 // drift coeficient correction
 338 //   const Double_t kTime0Cor         = 0.32;                 // time0 correction
 339 //   //
 340 //   const Double_t kX0shift           = 2.52;
 341 //   const Double_t kX0shift5          = 3.05;
 342
 343 //   //
 344 //   // apply alignment and calibration to transform cluster
 345 //   //
 346 //   //
 347 //   Int_t detector = cluster->GetDetector();
 348 //   Int_t plane   = fGeom->GetPlane(cluster->GetDetector());
 349 //   Int_t chamber = fGeom->GetChamber(cluster->GetDetector());
 350 //   Int_t sector  = fGeom->GetSector(cluster->GetDetector());
 351
 352 //   Double_t dxAmp  = (Double_t) fGeom->CamHght();          // Amplification region
 353 //   Double_t driftX = TMath::Max(cluster->GetX()-dxAmp*0.5,0.);  // drift distance
 354 //   //
 355 //   // ExB correction
 356 //   //
 357 //   Double_t vdrift = AliTRDcalibDB::Instance()->GetVdrift(cluster->GetDetector(),0,0);
 358 //   Double_t exB =   AliTRDcalibDB::Instance()->GetOmegaTau(vdrift);
 359 //   //
 360
 361 //   AliTRDCommonParam* commonParam = AliTRDCommonParam::Instance();
 362 //   AliTRDpadPlane * padPlane = commonParam->GetPadPlane(plane,chamber);
 363 //   Double_t zshiftIdeal  = 0.5*(padPlane->GetRow0()+padPlane->GetRowEnd());
 364 //   Double_t localPos[3], globalPos[3], localPosTracker[3], localPosTracker2[3];
 365 //   localPos[2] = -cluster->GetX();
 366 //   localPos[0] =  cluster->GetY() - driftX*exB;
 367 //   localPos[1] =  cluster->GetZ() -zshiftIdeal;
 368 //   TGeoHMatrix * matrix =  fGeom->GetGeoMatrix(cluster->GetDetector());
 369 //   matrix->LocalToMaster(localPos, globalPos);
 370
 371 //   Double_t sectorAngle = 20.*(sector%18)+10;
 372 //   TGeoHMatrix  rotSector;
 373 //   rotSector.RotateZ(sectorAngle);
 374 //   rotSector.LocalToMaster(globalPos, localPosTracker);
 375 //   //
 376 //   //
 377 //   TGeoHMatrix  matrix2(*matrix);
 378 //   matrix2.MultiplyLeft(&rotSector);
 379 //   matrix2.LocalToMaster(localPos,localPosTracker2);
 380 //   //
 381 //   //
 382 //   //
 383 //   cluster->SetY(cluster->GetY() - driftX*exB);
 384 //   Double_t xplane = (Double_t) AliTRDgeometry::GetTime0(plane);
 385 //   cluster->SetX(xplane- kDriftCorrection*(cluster->GetX()-kTime0Cor));
 386 //   (*fDebugStreamer)<<"Transform"<<
 387 //     "Cl.="<<cluster<<
 388 //     "matrix.="<<matrix<<
 389 //     "matrix2.="<<&matrix2<<
 390 //     "Detector="<<detector<<
 391 //     "Sector="<<sector<<
 392 //     "Plane="<<plane<<
 393 //     "Chamber="<<chamber<<
 394 //     "lx0="<<localPosTracker[0]<<
 395 //     "ly0="<<localPosTracker[1]<<
 396 //     "lz0="<<localPosTracker[2]<<
 397 //     "lx2="<<localPosTracker2[0]<<
 398 //     "ly2="<<localPosTracker2[1]<<
 399 //     "lz2="<<localPosTracker2[2]<<
 400 //     "\n";
 401 //   //
 402 //   if (plane==5)
 403 //      cluster->SetX(localPosTracker[0]+kX0shift5);
 404 //   else
 405 //     cluster->SetX(localPosTracker[0]+kX0shift);
 406
 407 //   cluster->SetY(localPosTracker[1]);
 408 //   cluster->SetZ(localPosTracker[2]);
 409 //   return kTRUE;
 410 // }
 411
 412 //_____________________________________________________________________________
 413 Bool_t AliTRDtracker::AdjustSector(AliTRDtrack *track)
 414 {
 415   //
 416   // Rotates the track when necessary
 417   //
 418
 419   Double_t alpha = AliTRDgeometry::GetAlpha();
 420   Double_t y = track->GetY();
 421   Double_t ymax = track->GetX()*TMath::Tan(0.5*alpha);
 422
 423   //Int_t ns = AliTRDgeometry::kNsect;
 424   //Int_t s=Int_t(track->GetAlpha()/alpha)%ns;
 425
 426   if (y > ymax) {
 427     //s = (s+1) % ns;
 428     if (!track->Rotate(alpha)) return kFALSE;
 429   } else if (y <-ymax) {
 430     //s = (s-1+ns) % ns;
 431     if (!track->Rotate(-alpha)) return kFALSE;
 432   }
 433
 434   return kTRUE;
 435
 436 }
 437
 438 //_____________________________________________________________________________
 439 AliTRDcluster *AliTRDtracker::GetCluster(AliTRDtrack *track, Int_t plane
 440                                        , Int_t timebin, UInt_t &index)
 441 {
 442   //
 443   // Try to find cluster in the backup list
 444   //
 445
 446   AliTRDcluster * cl =0;
 447   Int_t *indexes = track->GetBackupIndexes();
 448   for (UInt_t i=0;i<kMaxTimeBinIndex;i++){
 449     if (indexes[i]==0) break;
 450     AliTRDcluster * cli = (AliTRDcluster*)fClusters->UncheckedAt(indexes[i]);
 451     if (!cli) break;
 452     if (cli->GetLocalTimeBin()!=timebin) continue;
 453     Int_t iplane = fGeom->GetPlane(cli->GetDetector());
 454     if (iplane==plane) {
 455       cl = cli;
 456       index = indexes[i];
 457       break;
 458     }
 459   }
 460
 461   return cl;
 462
 463 }
 464
 465 //_____________________________________________________________________________
 466 Int_t  AliTRDtracker::GetLastPlane(AliTRDtrack * track)
 467 {
 468   //
 469   // Return last updated plane
 470   //
 471
 472   Int_t lastplane=0;
 473   Int_t *indexes = track->GetBackupIndexes();
 474   for (UInt_t i=0;i<kMaxTimeBinIndex;i++){
 475     AliTRDcluster * cli = (AliTRDcluster*)fClusters->UncheckedAt(indexes[i]);
 476     if (!cli) break;
 477     Int_t iplane = fGeom->GetPlane(cli->GetDetector());
 478     if (iplane>lastplane) {
 479       lastplane = iplane;
 480     }
 481   }
 482
 483   return lastplane;
 484
 485 }
 486
 487 //_____________________________________________________________________________
 488 Int_t AliTRDtracker::Clusters2Tracks(AliESD* event)
 489 {
 490   //
 491   // Finds tracks within the TRD. The ESD event is expected to contain seeds
 492   // at the outer part of the TRD. The seeds
 493   // are found within the TRD if fAddTRDseeds is TRUE.
 494   // The tracks are propagated to the innermost time bin
 495   // of the TRD and the ESD event is updated
 496   //
 497
 498   Int_t timeBins = fTrSec[0]->GetNumberOfTimeBins();
 499   Float_t foundMin = fgkMinClustersInTrack * timeBins;
 500   Int_t nseed = 0;
 501   Int_t found = 0;
 502   //  Int_t innerTB = fTrSec[0]->GetInnerTimeBin();
 503
 504   Int_t n = event->GetNumberOfTracks();
 505   for (Int_t i=0; i<n; i++) {
 506     AliESDtrack* seed=event->GetTrack(i);
 507     ULong_t status=seed->GetStatus();
 508     if ( (status & AliESDtrack::kTRDout ) == 0 ) continue;
 509     if ( (status & AliESDtrack::kTRDin) != 0 ) continue;
 510     nseed++;
 511
 512     AliTRDtrack* seed2 = new AliTRDtrack(*seed);
 513     //seed2->ResetCovariance();
 514     AliTRDtrack *pt = new AliTRDtrack(*seed2,seed2->GetAlpha());
 515     AliTRDtrack &t=*pt;
 516     FollowProlongation(t);
 517     if (t.GetNumberOfClusters() >= foundMin) {
 518       UseClusters(&t);
 519       CookLabel(pt, 1-fgkLabelFraction);
 520       //      t.CookdEdx();
 521     }
 522     found++;
 523 //    cout<<found<<'\r';
 524
 525     Double_t xTPC = 250;
 526     if (PropagateToX(t,xTPC,fgkMaxStep)) {
 527       seed->UpdateTrackParams(pt, AliESDtrack::kTRDin);
 528     }
 529     delete seed2;
 530     delete pt;
 531   }
 532
 533   cout<<"Number of loaded seeds: "<<nseed<<endl;
 534   cout<<"Number of found tracks from loaded seeds: "<<found<<endl;
 535
 536   // after tracks from loaded seeds are found and the corresponding
 537   // clusters are used, look for additional seeds from TRD
 538
 539
 540   cout<<"Total number of found tracks: "<<found<<endl;
 541
 542   return 0;
 543
 544 }
 545
 546 //_____________________________________________________________________________
 547 Int_t AliTRDtracker::PropagateBack(AliESD* event)
 548 {
 549   //
 550   // Gets seeds from ESD event. The seeds are AliTPCtrack's found and
 551   // backpropagated by the TPC tracker. Each seed is first propagated
 552   // to the TRD, and then its prolongation is searched in the TRD.
 553   // If sufficiently long continuation of the track is found in the TRD
 554   // the track is updated, otherwise it's stored as originaly defined
 555   // by the TPC tracker.
 556   //
 557
 558   Int_t found=0;
 559   Float_t foundMin = 20;
 560   Int_t n = event->GetNumberOfTracks();
 561   //
 562   //Sort tracks
 563   Float_t *quality =new Float_t[n];
 564   Int_t *index   =new Int_t[n];
 565   for (Int_t i=0; i<n; i++) {
 566     AliESDtrack* seed=event->GetTrack(i);
 567     Double_t covariance[15];
 568     seed->GetExternalCovariance(covariance);
 569     quality[i] = covariance[0]+covariance[2];
 570   }
 571   TMath::Sort(n,quality,index,kFALSE);
 572   //
 573   for (Int_t i=0; i<n; i++) {
 574     //    AliESDtrack* seed=event->GetTrack(i);
 575     AliESDtrack* seed=event->GetTrack(index[i]);
 576
 577     ULong_t status=seed->GetStatus();
 578     if ( (status & AliESDtrack::kTPCout ) == 0 ) continue;
 579     if ( (status & AliESDtrack::kTRDout) != 0 ) continue;
 580
 581     Int_t lbl = seed->GetLabel();
 582     AliTRDtrack *track = new AliTRDtrack(*seed);
 583     track->SetSeedLabel(lbl);
 584     seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup); //make backup
 585     fNseeds++;
 586     Float_t p4     = track->GetC();
 587     //
 588     Int_t expectedClr = FollowBackProlongation(*track);
 589     if (TMath::Abs(track->GetC()-p4)/TMath::Abs(p4)<0.2 || TMath::Abs(track->GetPt())>0.8 ) {
 590       //
 591       //make backup for back propagation
 592       //
 593       Int_t foundClr = track->GetNumberOfClusters();
 594       if (foundClr >= foundMin) {
 595         track->CookdEdx();
 596         CookdEdxTimBin(*track);
 597         CookLabel(track, 1-fgkLabelFraction);
 598         if (track->GetBackupTrack()) UseClusters(track->GetBackupTrack());
 599         if(track->GetChi2()/track->GetNumberOfClusters()<4) {   // sign only gold tracks
 600           if (seed->GetKinkIndex(0)==0&&TMath::Abs(track->GetPt())<1.5 ) UseClusters(track);
 601         }
 602         Bool_t isGold = kFALSE;
 603
 604         if (track->GetChi2()/track->GetNumberOfClusters()<5) {  //full gold track
 605           // seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
 606            if (track->GetBackupTrack()) seed->UpdateTrackParams(track->GetBackupTrack(), AliESDtrack::kTRDbackup);
 607           isGold = kTRUE;
 608         }
 609         if (!isGold && track->GetNCross()==0&&track->GetChi2()/track->GetNumberOfClusters()<7){ //almost gold track
 610           //      seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
 611           if (track->GetBackupTrack()) seed->UpdateTrackParams(track->GetBackupTrack(), AliESDtrack::kTRDbackup);
 612           isGold = kTRUE;
 613         }
 614         if (!isGold && track->GetBackupTrack()){
 615           if (track->GetBackupTrack()->GetNumberOfClusters()>foundMin&&
 616               (track->GetBackupTrack()->GetChi2()/(track->GetBackupTrack()->GetNumberOfClusters()+1))<7){
 617             seed->UpdateTrackParams(track->GetBackupTrack(), AliESDtrack::kTRDbackup);
 618             isGold = kTRUE;
 619           }
 620         }
 621         if (track->StatusForTOF()>0 &&track->fNCross==0 && Float_t(track->fN)/Float_t(track->fNExpected)>0.4){
 622           //seed->UpdateTrackParams(track->GetBackupTrack(), AliESDtrack::kTRDbackup);
 623         }
 624       }
 625     }
 626     // Debug part of tracking
 627     TTreeSRedirector& cstream = *fDebugStreamer;
 628     Int_t eventNr = event->GetEventNumber();
 629     if (AliTRDReconstructor::StreamLevel()>0){
 630       if (track->GetBackupTrack()){
 631         cstream<<"Tracks"<<
 632           "EventNr="<<eventNr<<
 633           "ESD.="<<seed<<
 634           "trd.="<<track<<
 635           "trdback.="<<track->GetBackupTrack()<<
 636           "\n";
 637       }else{
 638         cstream<<"Tracks"<<
 639           "EventNr="<<eventNr<<
 640           "ESD.="<<seed<<
 641           "trd.="<<track<<
 642           "trdback.="<<track<<
 643           "\n";
 644       }
 645     }
 646     //
 647     //Propagation to the TOF (I.Belikov)
 648     if (track->GetStop()==kFALSE){
 649
 650       Double_t xtof=371.;
 651       Double_t c2=track->GetC()*xtof - track->GetEta();
 652       if (TMath::Abs(c2)>=0.99) {
 653         delete track;
 654         continue;
 655       }
 656       Double_t xTOF0 = 370. ;
 657       PropagateToX(*track,xTOF0,fgkMaxStep);
 658       //
 659       //energy losses taken to the account - check one more time
 660       c2=track->GetC()*xtof - track->GetEta();
 661       if (TMath::Abs(c2)>=0.99) {
 662         delete track;
 663         continue;
 664       }
 665
 666       //
 667       Double_t ymax=xtof*TMath::Tan(0.5*AliTRDgeometry::GetAlpha());
 668       Double_t y=track->GetYat(xtof);
 669       if (y > ymax) {
 670         if (!track->Rotate(AliTRDgeometry::GetAlpha())) {
 671           delete track;
 672           continue;
 673         }
 674       } else if (y <-ymax) {
 675         if (!track->Rotate(-AliTRDgeometry::GetAlpha())) {
 676           delete track;
 677           continue;
 678         }
 679       }
 680
 681       if (track->PropagateTo(xtof)) {
 682         seed->UpdateTrackParams(track, AliESDtrack::kTRDout);
 683         for (Int_t i=0;i<AliESDtrack::kNPlane;i++) {
 684           for (Int_t j=0;j<AliESDtrack::kNSlice;j++) {
 685             seed->SetTRDsignals(track->GetPIDsignals(i,j),i,j);
 686           }
 687           seed->SetTRDTimBin(track->GetPIDTimBin(i),i);
 688         }
 689         //      seed->SetTRDtrack(new AliTRDtrack(*track));
 690         if (track->GetNumberOfClusters()>foundMin) found++;
 691       }
 692     }else{
 693       if (track->GetNumberOfClusters()>15&&track->GetNumberOfClusters()>0.5*expectedClr){
 694         seed->UpdateTrackParams(track, AliESDtrack::kTRDout);
 695         //seed->SetStatus(AliESDtrack::kTRDStop);
 696         for (Int_t i=0;i<AliESDtrack::kNPlane;i++) {
 697           for (Int_t j=0;j<AliESDtrack::kNSlice;j++) {
 698             seed->SetTRDsignals(track->GetPIDsignals(i,j),i,j);
 699           }
 700           seed->SetTRDTimBin(track->GetPIDTimBin(i),i);
 701         }
 702         //seed->SetTRDtrack(new AliTRDtrack(*track));
 703         found++;
 704       }
 705     }
 706     seed->SetTRDQuality(track->StatusForTOF());
 707     seed->SetTRDBudget(track->fBudget[0]);
 708
 709     delete track;
 710     //
 711     //End of propagation to the TOF
 712     //if (foundClr>foundMin)
 713     //  seed->UpdateTrackParams(track, AliESDtrack::kTRDout);
 714
 715
 716   }
 717
 718   cerr<<"Number of seeds: "<<fNseeds<<endl;
 719   cerr<<"Number of back propagated TRD tracks: "<<found<<endl;
 720
 721   if (AliTRDReconstructor::SeedingOn()) MakeSeedsMI(3,5,event); //new seeding
 722
 723   fSeeds->Clear(); fNseeds=0;
 724   delete [] index;
 725   delete [] quality;
 726
 727   return 0;
 728
 729 }
 730
 731 //_____________________________________________________________________________
 732 Int_t AliTRDtracker::RefitInward(AliESD* event)
 733 {
 734   //
 735   // Refits tracks within the TRD. The ESD event is expected to contain seeds
 736   // at the outer part of the TRD.
 737   // The tracks are propagated to the innermost time bin
 738   // of the TRD and the ESD event is updated
 739   // Origin: Thomas KUHR (Thomas.Kuhr@cern.ch)
 740   //
 741
 742   Int_t timeBins = fTrSec[0]->GetNumberOfTimeBins();
 743   Float_t foundMin = fgkMinClustersInTrack * timeBins;
 744   Int_t nseed = 0;
 745   Int_t found = 0;
 746   //  Int_t innerTB = fTrSec[0]->GetInnerTimeBin();
 747   AliTRDtrack seed2;
 748
 749   Int_t n = event->GetNumberOfTracks();
 750   for (Int_t i=0; i<n; i++) {
 751     AliESDtrack* seed=event->GetTrack(i);
 752     new(&seed2) AliTRDtrack(*seed);
 753     if (seed2.GetX()<270){
 754       seed->UpdateTrackParams(&seed2, AliESDtrack::kTRDbackup); // backup TPC track - only update
 755       continue;
 756     }
 757
 758     ULong_t status=seed->GetStatus();
 759     if ( (status & AliESDtrack::kTRDout ) == 0 ) {
 760       continue;
 761     }
 762     if ( (status & AliESDtrack::kTRDin) != 0 ) {
 763       continue;
 764     }
 765     nseed++;
 766 //     if (1/seed2.Get1Pt()>1.5&& seed2.GetX()>260.) {
 767 //       Double_t oldx = seed2.GetX();
 768 //       seed2.PropagateTo(500.);
 769 //       seed2.ResetCovariance(1.);
 770 //       seed2.PropagateTo(oldx);
 771 //     }
 772 //     else{
 773 //       seed2.ResetCovariance(5.);
 774 //     }
 775
 776     AliTRDtrack *pt = new AliTRDtrack(seed2,seed2.GetAlpha());
 777     Int_t * indexes2 = seed2.GetIndexes();
 778     for (Int_t i=0;i<AliESDtrack::kNPlane;i++) {
 779       for (Int_t j=0;j<AliESDtrack::kNSlice;j++) {
 780         pt->SetPIDsignals(seed2.GetPIDsignals(i,j),i,j);
 781       }
 782       pt->SetPIDTimBin(seed2.GetPIDTimBin(i),i);
 783     }
 784
 785     Int_t * indexes3 = pt->GetBackupIndexes();
 786     for (Int_t i=0;i<200;i++) {
 787       if (indexes2[i]==0) break;
 788       indexes3[i] = indexes2[i];
 789     }
 790     //AliTRDtrack *pt = seed2;
 791     AliTRDtrack &t=*pt;
 792     FollowProlongation(t);
 793     if (t.GetNumberOfClusters() >= foundMin) {
 794       //      UseClusters(&t);
 795       //CookLabel(pt, 1-fgkLabelFraction);
 796       t.CookdEdx();
 797       CookdEdxTimBin(t);
 798     }
 799     found++;
 800 //    cout<<found<<'\r';
 801     Double_t xTPC = 250;
 802     if(PropagateToX(t,xTPC,fgkMaxStep)) {
 803       seed->UpdateTrackParams(pt, AliESDtrack::kTRDrefit);
 804       for (Int_t i=0;i<AliESDtrack::kNPlane;i++) {
 805         for (Int_t j=0;j<AliESDtrack::kNSlice;j++) {
 806           seed->SetTRDsignals(pt->GetPIDsignals(i,j),i,j);
 807         }
 808         seed->SetTRDTimBin(pt->GetPIDTimBin(i),i);
 809       }
 810     }else{
 811       //if not prolongation to TPC - propagate without update
 812       AliTRDtrack* seed2 = new AliTRDtrack(*seed);
 813       seed2->ResetCovariance(5.);
 814       AliTRDtrack *pt2 = new AliTRDtrack(*seed2,seed2->GetAlpha());
 815       delete seed2;
 816       if (PropagateToX(*pt2,xTPC,fgkMaxStep)) {
 817         //pt2->CookdEdx(0.,1.);
 818         pt2->CookdEdx( ); // Modification by PS
 819         CookdEdxTimBin(*pt2);
 820         seed->UpdateTrackParams(pt2, AliESDtrack::kTRDrefit);
 821         for (Int_t i=0;i<AliESDtrack::kNPlane;i++) {
 822           for (Int_t j=0;j<AliESDtrack::kNSlice;j++) {
 823             seed->SetTRDsignals(pt2->GetPIDsignals(i,j),i,j);
 824           }
 825           seed->SetTRDTimBin(pt2->GetPIDTimBin(i),i);
 826         }
 827       }
 828       delete pt2;
 829     }
 830     delete pt;
 831   }
 832
 833   cout<<"Number of loaded seeds: "<<nseed<<endl;
 834   cout<<"Number of found tracks from loaded seeds: "<<found<<endl;
 835
 836   return 0;
 837
 838 }
 839
 840 //_____________________________________________________________________________
 841 Int_t AliTRDtracker::FollowProlongation(AliTRDtrack& t)
 842 {
 843   //
 844   // Starting from current position on track=t this function tries
 845   // to extrapolate the track up to timeBin=0 and to confirm prolongation
 846   // if a close cluster is found. Returns the number of clusters
 847   // expected to be found in sensitive layers
 848   // GeoManager used to estimate mean density
 849   //
 850
 851   Int_t sector;
 852   Int_t lastplane = GetLastPlane(&t);
 853   Double_t radLength = 0.0;
 854   Double_t rho = 0.0;
 855   Int_t expectedNumberOfClusters = 0;
 856   //
 857   //
 858   //
 859   for (Int_t iplane = lastplane; iplane>=0; iplane--){
 860     //
 861     Int_t    row0 = GetGlobalTimeBin(0, iplane,GetTimeBinsPerPlane()-1);
 862     Int_t    rowlast = GetGlobalTimeBin(0, iplane,0);
 863     //
 864     // propagate track close to the plane if neccessary
 865     //
 866     Double_t currentx  = fTrSec[0]->GetLayer(rowlast)->GetX();
 867     if (currentx < -fgkMaxStep +t.GetX()){
 868       //propagate closer to chamber - safety space fgkMaxStep
 869       if (!PropagateToX(t, currentx+fgkMaxStep, fgkMaxStep)) break;
 870     }
 871     if (!AdjustSector(&t)) break;
 872     //
 873     // get material budget
 874     //
 875     Double_t xyz0[3],xyz1[3],param[7],x,y,z;
 876     t.GetGlobalXYZ(xyz0[0],xyz0[1],xyz0[2]);   //starting global position
 877     // end global position
 878     x = fTrSec[0]->GetLayer(row0)->GetX();
 879     if (!t.GetProlongation(x,y,z)) break;
 880     xyz1[0] = x*TMath::Cos(t.GetAlpha())-y*TMath::Sin(t.GetAlpha());
 881     xyz1[1] = +x*TMath::Sin(t.GetAlpha())+y*TMath::Cos(t.GetAlpha());
 882     xyz1[2] = z;
 883     AliKalmanTrack::MeanMaterialBudget(xyz0,xyz1,param);
 884     rho = param[0];
 885     radLength = param[1];   // get mean propagation parameters
 886     //
 887     // propagate nad update
 888     //
 889     sector = t.GetSector();
 890     //    for (Int_t itime=GetTimeBinsPerPlane()-1;itime>=0;itime--) {
 891     for (Int_t itime=0 ;itime<GetTimeBinsPerPlane();itime++) {
 892       Int_t    ilayer = GetGlobalTimeBin(0, iplane,itime);
 893       expectedNumberOfClusters++;
 894       t.fNExpected++;
 895       if (t.fX>345) t.fNExpectedLast++;
 896       AliTRDpropagationLayer& timeBin=*(fTrSec[sector]->GetLayer(ilayer));
 897       AliTRDcluster *cl=0;
 898       UInt_t index=0;
 899       Double_t maxChi2=fgkMaxChi2;
 900       x = timeBin.GetX();
 901       if (timeBin) {
 902         AliTRDcluster * cl0 = timeBin[0];
 903         if (!cl0) continue;         // no clusters in given time bin
 904         Int_t plane = fGeom->GetPlane(cl0->GetDetector());
 905         if (plane>lastplane) continue;
 906         Int_t timebin = cl0->GetLocalTimeBin();
 907         AliTRDcluster * cl2= GetCluster(&t,plane, timebin,index);
 908         //
 909         if (cl2) {
 910           cl =cl2;
 911           Double_t h01 = GetTiltFactor(cl);
 912           maxChi2=t.GetPredictedChi2(cl,h01);
 913         }
 914         if (cl) {
 915           //      if (cl->GetNPads()<5)
 916           Double_t dxsample = timeBin.GetdX();
 917           t.SetSampledEdx(TMath::Abs(cl->GetQ()/dxsample));
 918           Double_t h01 = GetTiltFactor(cl);
 919           Int_t det = cl->GetDetector();
 920           Int_t plane = fGeom->GetPlane(det);
 921           if (t.fX>345){
 922             t.fNLast++;
 923             t.fChi2Last+=maxChi2;
 924           }
 925           Double_t xcluster = cl->GetX();
 926           t.PropagateTo(xcluster,radLength,rho);
 927           if(!t.UpdateMI(cl,maxChi2,index,h01,plane)) {
 928           }
 929         }
 930       }
 931     }
 932   }
 933
 934   return expectedNumberOfClusters;
 935
 936 }
 937
 938 //_____________________________________________________________________________
 939 Int_t AliTRDtracker::FollowBackProlongation(AliTRDtrack& t)
 940 {
 941   //
 942   // Starting from current radial position of track <t> this function
 943   // extrapolates the track up to outer timebin and in the sensitive
 944   // layers confirms prolongation if a close cluster is found.
 945   // Returns the number of clusters expected to be found in sensitive layers
 946   // Use GEO manager for material Description
 947   //
 948
 949   Int_t sector;
 950   Int_t clusters[1000];
 951   for (Int_t i=0;i<1000;i++) clusters[i]=-1;
 952   Double_t radLength = 0.0;
 953   Double_t rho = 0.0;
 954   Int_t expectedNumberOfClusters = 0;
 955   Float_t ratio0=0;
 956   AliTRDtracklet tracklet;
 957   //
 958   //
 959   for (Int_t iplane = 0; iplane<AliESDtrack::kNPlane; iplane++){
 960     Int_t    row0    = GetGlobalTimeBin(0, iplane,GetTimeBinsPerPlane()-1);
 961     Int_t    rowlast = GetGlobalTimeBin(0, iplane,0);
 962     //
 963     Double_t currentx  = fTrSec[0]->GetLayer(row0)->GetX();
 964     if (currentx<t.GetX()) continue;
 965     //
 966     //       propagate closer to chamber if neccessary
 967     //
 968     if (currentx > fgkMaxStep +t.GetX()){
 969       if (!PropagateToX(t, currentx-fgkMaxStep, fgkMaxStep)) break;
 970     }
 971     if (!AdjustSector(&t)) break;
 972     if (TMath::Abs(t.GetSnp())>fgkMaxSnp) break;
 973     //
 974     // get material budget inside of chamber
 975     //
 976     Double_t xyz0[3],xyz1[3],param[7],x,y,z;
 977     t.GetGlobalXYZ(xyz0[0],xyz0[1],xyz0[2]);   //starting global position
 978     // end global position
 979     x = fTrSec[0]->GetLayer(rowlast)->GetX();
 980     if (!t.GetProlongation(x,y,z)) break;
 981     xyz1[0] = x*TMath::Cos(t.GetAlpha())-y*TMath::Sin(t.GetAlpha());
 982     xyz1[1] = +x*TMath::Sin(t.GetAlpha())+y*TMath::Cos(t.GetAlpha());
 983     xyz1[2] = z;
 984     AliKalmanTrack::MeanMaterialBudget(xyz0,xyz1,param);
 985     rho = param[0];
 986     radLength = param[1];   // get mean propagation parameters
 987     //
 988     // Find clusters
 989     //
 990     sector = t.GetSector();
 991     Float_t  ncl   = FindClusters(sector,row0,rowlast,&t,clusters,tracklet);
 992     if (tracklet.GetN()<GetTimeBinsPerPlane()/3) continue;
 993     //
 994     // Propagate and update track
 995     //
 996     for (Int_t itime= GetTimeBinsPerPlane()-1;itime>=0;itime--) {
 997       Int_t    ilayer = GetGlobalTimeBin(0, iplane,itime);
 998       expectedNumberOfClusters++;
 999       t.fNExpected++;
1000       if (t.fX>345) t.fNExpectedLast++;
1001       AliTRDpropagationLayer& timeBin=*(fTrSec[sector]->GetLayer(ilayer));
1002       AliTRDcluster *cl=0;
1003       UInt_t index=0;
1004       Double_t maxChi2=fgkMaxChi2;
1005       x = timeBin.GetX();
1006       //
1007       if (timeBin) {
1008         if (clusters[ilayer]>0) {
1009           index = clusters[ilayer];
1010           cl    = (AliTRDcluster*)GetCluster(index);
1011           Double_t h01 = GetTiltFactor(cl);
1012           maxChi2=t.GetPredictedChi2(cl,h01);
1013         }
1014
1015         if (cl) {
1016           //      if (cl->GetNPads()<5)
1017           Double_t dxsample = timeBin.GetdX();
1018           t.SetSampledEdx(TMath::Abs(cl->GetQ()/dxsample));
1019           Double_t h01 = GetTiltFactor(cl);
1020           Int_t det = cl->GetDetector();
1021           Int_t plane = fGeom->GetPlane(det);
1022           if (t.fX>345){
1023             t.fNLast++;
1024             t.fChi2Last+=maxChi2;
1025           }
1026           Double_t xcluster = cl->GetX();
1027           t.PropagateTo(xcluster,radLength,rho);
1028           if(!t.UpdateMI(cl,maxChi2,index,h01,plane)) {
1029             if(!t.Update(cl,maxChi2,index,h01)) {
1030             }
1031           }
1032           //
1033           // reset material budget if 2 consecutive gold
1034           if (plane>0)
1035             if (t.fTracklets[plane].GetN()+t.fTracklets[plane-1].GetN()>20){
1036               t.fBudget[2] = 0;
1037             }
1038         }
1039       }
1040     }
1041     ratio0 = ncl/Float_t(fTimeBinsPerPlane);
1042     Float_t  ratio1 = Float_t(t.fN+1)/Float_t(t.fNExpected+1.);
1043     if (tracklet.GetChi2()<18.&&ratio0>0.8 && ratio1>0.6 && ratio0+ratio1>1.5 && t.GetNCross()==0 && TMath::Abs(t.GetSnp())<0.85&&t.fN>20){
1044       t.MakeBackupTrack();                            // make backup of the track until is gold
1045     }
1046
1047   }
1048
1049   return expectedNumberOfClusters;
1050
1051 }
1052
1053 //_____________________________________________________________________________
1054 Int_t  AliTRDtracker::PropagateToX(AliTRDtrack& t, Double_t xToGo, Double_t maxStep)
1055 {
1056   //
1057   // Starting from current radial position of track <t> this function
1058   // extrapolates the track up to radial position <xToGo>.
1059   // Returns 1 if track reaches the plane, and 0 otherwise
1060   //
1061
1062   const Double_t kEpsilon = 0.00001;
1063   //  Double_t tanmax = TMath::Tan(0.5*AliTRDgeometry::GetAlpha());
1064   Double_t xpos     = t.GetX();
1065   Double_t dir      = (xpos<xToGo) ? 1.:-1.;
1066   //
1067   while ( (xToGo-xpos)*dir > kEpsilon){
1068     Double_t step = dir*TMath::Min(TMath::Abs(xToGo-xpos), maxStep);
1069     //
1070     Double_t xyz0[3],xyz1[3],param[7],x,y,z;
1071     t.GetGlobalXYZ(xyz0[0],xyz0[1],xyz0[2]);   //starting global position
1072     x    = xpos+step;
1073     //
1074     if (!t.GetProlongation(x,y,z)) return 0;   // no prolongation
1075     //
1076     xyz1[0] = x*TMath::Cos(t.GetAlpha())-y*TMath::Sin(t.GetAlpha());
1077     xyz1[1] = +x*TMath::Sin(t.GetAlpha())+y*TMath::Cos(t.GetAlpha());
1078     xyz1[2] = z;
1079     //
1080     AliKalmanTrack::MeanMaterialBudget(xyz0,xyz1,param);
1081     if (!t.PropagateTo(x,param[1],param[0])) return 0;
1082     AdjustSector(&t);
1083     xpos = t.GetX();
1084   }
1085
1086   return 1;
1087
1088 }
1089
1090 //_____________________________________________________________________________
1091 Int_t AliTRDtracker::LoadClusters(TTree *cTree)
1092 {
1093   //
1094   // Fills clusters into TRD tracking_sectors
1095   // Note that the numbering scheme for the TRD tracking_sectors
1096   // differs from that of TRD sectors
1097   //
1098
1099   cout<<"\n Read Sectors  clusters"<<endl;
1100   if (ReadClusters(fClusters,cTree)) {
1101      Error("LoadClusters","Problem with reading the clusters !");
1102      return 1;
1103   }
1104   Int_t ncl=fClusters->GetEntriesFast();
1105   fNclusters=ncl;
1106   cout<<"\n LoadSectors: sorting "<<ncl<<" clusters"<<endl;
1107
1108   UInt_t index;
1109   for (Int_t ichamber=0;ichamber<5;ichamber++)
1110     for (Int_t isector=0;isector<18;isector++){
1111       fHoles[ichamber][isector]=kTRUE;
1112     }
1113
1114
1115   while (ncl--) {
1116 //    printf("\r %d left  ",ncl);
1117     AliTRDcluster *c=(AliTRDcluster*)fClusters->UncheckedAt(ncl);
1118     Int_t detector=c->GetDetector();
1119     Int_t localTimeBin=c->GetLocalTimeBin();
1120     Int_t sector=fGeom->GetSector(detector);
1121     Int_t plane=fGeom->GetPlane(detector);
1122
1123     Int_t trackingSector = CookSectorIndex(sector);
1124     if (c->GetLabel(0)>0){
1125       Int_t chamber = fGeom->GetChamber(detector);
1126       fHoles[chamber][trackingSector]=kFALSE;
1127     }
1128
1129     Int_t gtb = fTrSec[trackingSector]->CookTimeBinIndex(plane,localTimeBin);
1130     if(gtb < 0) continue;
1131     Int_t layer = fTrSec[trackingSector]->GetLayerNumber(gtb);
1132
1133     index=ncl;
1134     //
1135     // apply pos correction
1136     Transform(c);
1137     fTrSec[trackingSector]->GetLayer(layer)->InsertCluster(c,index);
1138   }
1139
1140   return 0;
1141
1142 }
1143
1144 //_____________________________________________________________________________
1145 void AliTRDtracker::UnloadClusters()
1146 {
1147   //
1148   // Clears the arrays of clusters and tracks. Resets sectors and timebins
1149   //
1150
1151   Int_t i, nentr;
1152
1153   nentr = fClusters->GetEntriesFast();
1154   for (i = 0; i < nentr; i++) delete fClusters->RemoveAt(i);
1155   fNclusters = 0;
1156
1157   nentr = fSeeds->GetEntriesFast();
1158   for (i = 0; i < nentr; i++) delete fSeeds->RemoveAt(i);
1159
1160   nentr = fTracks->GetEntriesFast();
1161   for (i = 0; i < nentr; i++) delete fTracks->RemoveAt(i);
1162
1163   Int_t nsec = AliTRDgeometry::kNsect;
1164
1165   for (i = 0; i < nsec; i++) {
1166     for(Int_t pl = 0; pl < fTrSec[i]->GetNumberOfLayers(); pl++) {
1167       fTrSec[i]->GetLayer(pl)->Clear();
1168     }
1169   }
1170
1171 }
1172
1173 //_____________________________________________________________________________
1174 void AliTRDtracker::MakeSeedsMI(Int_t /*inner*/, Int_t /*outer*/, AliESD * esd)
1175 {
1176   //
1177   // Creates  seeds using clusters between  position inner plane  and outer plane
1178   //
1179
1180   const Double_t kMaxTheta = 1;
1181   const Double_t kMaxPhi   = 2.0;
1182   //
1183   const Double_t kRoad0y  =  6;     // road for middle cluster
1184   const Double_t kRoad0z  =  8.5;   // road for middle cluster
1185   //
1186   const Double_t kRoad1y  =  2;    // road in y for seeded cluster
1187   const Double_t kRoad1z  =  20;    // road in z for seeded cluster
1188   //
1189   const Double_t kRoad2y  =  3;    // road in y for extrapolated cluster
1190   const Double_t kRoad2z  =  20;   // road in z for extrapolated cluster
1191   const Int_t    kMaxSeed  = 3000;
1192   Int_t maxSec=AliTRDgeometry::kNsect;
1193
1194   //
1195   // linear fitters in planes
1196   TLinearFitter fitterTC(2,"hyp2");  // fitting with tilting pads - kz fixed - kz= Z/x, + vertex const
1197   TLinearFitter fitterT2(4,"hyp4");  // fitting with tilting pads - kz not fixed
1198   fitterTC.StoreData(kTRUE);
1199   fitterT2.StoreData(kTRUE);
1200   AliRieman rieman(1000);   // rieman fitter
1201   AliRieman rieman2(1000);   // rieman fitter
1202   //
1203   // find the maximal and minimal layer for the planes
1204   //
1205   Int_t layers[6][2];
1206   AliTRDpropagationLayer* reflayers[6];
1207   for (Int_t i=0;i<6;i++){layers[i][0]=10000; layers[i][1]=0;}
1208   for (Int_t ns=0;ns<maxSec;ns++){
1209     for (Int_t ilayer=0;ilayer<fTrSec[ns]->GetNumberOfLayers();ilayer++){
1210       AliTRDpropagationLayer& layer=*(fTrSec[ns]->GetLayer(ilayer));
1211       if (layer==0) continue;
1212       Int_t det   = layer[0]->GetDetector();
1213       Int_t plane = fGeom->GetPlane(det);
1214       if (ilayer<layers[plane][0]) layers[plane][0] = ilayer;
1215       if (ilayer>layers[plane][1]) layers[plane][1] = ilayer;
1216     }
1217   }
1218   //
1219   AliTRDpadPlane *padPlane = AliTRDCommonParam::Instance()->GetPadPlane(0,0);
1220   Double_t h01 = TMath::Tan(-TMath::Pi() / 180.0 * padPlane->GetTiltingAngle());
1221   Double_t hL[6];         // tilting angle
1222   Double_t xcl[6];        // x - position of reference cluster
1223   Double_t ycl[6];        // y - position of reference cluster
1224   Double_t zcl[6];        // z - position of reference cluster
1225   AliTRDcluster *cl[6]={0,0,0,0,0,0};    // seeding clusters
1226   Float_t padlength[6]={10,10,10,10,10,10};   //current pad-length
1227   Double_t chi2R =0, chi2Z=0;
1228   Double_t chi2RF =0, chi2ZF=0;
1229   //
1230   Int_t nclusters;     // total number of clusters
1231   for (Int_t i=0;i<6;i++) {hL[i]=h01; if (i%2==1) hL[i]*=-1.;}
1232   //
1233   //
1234   //         registered seed
1235   AliTRDseed *pseed = new AliTRDseed[kMaxSeed*6];
1236   AliTRDseed *seed[kMaxSeed];
1237   for (Int_t iseed=0;iseed<kMaxSeed;iseed++) seed[iseed]= &pseed[iseed*6];
1238   AliTRDseed *cseed = seed[0];
1239   //
1240   Double_t   seedquality[kMaxSeed];
1241   Double_t   seedquality2[kMaxSeed];
1242   Double_t   seedparams[kMaxSeed][7];
1243   Int_t      seedlayer[kMaxSeed];
1244   Int_t      registered =0;
1245   Int_t      sort[kMaxSeed];
1246   //
1247   // seeding part
1248   //
1249   for (Int_t ns = 0; ns<maxSec; ns++){         //loop over sectors
1250   //for (Int_t ns = 0; ns<5; ns++){         //loop over sectors
1251     registered = 0;   // reset registerd seed counter
1252     cseed      = seed[registered];
1253     Float_t iter=0;
1254     for (Int_t sLayer=2; sLayer>=0;sLayer--){
1255       //for (Int_t dseed=5;dseed<15; dseed+=3){  //loop over central seeding time bins
1256       iter+=1.;
1257       Int_t dseed = 5+Int_t(iter)*3;
1258       // Initialize seeding layers
1259       for (Int_t ilayer=0;ilayer<6;ilayer++){
1260         reflayers[ilayer] = fTrSec[ns]->GetLayer(layers[ilayer][1]-dseed);
1261         xcl[ilayer]       = reflayers[ilayer]->GetX();
1262       }
1263       //
1264       Double_t xref                 = (xcl[sLayer+1] + xcl[sLayer+2])*0.5;
1265       AliTRDpropagationLayer& layer0=*reflayers[sLayer+0];
1266       AliTRDpropagationLayer& layer1=*reflayers[sLayer+1];
1267       AliTRDpropagationLayer& layer2=*reflayers[sLayer+2];
1268       AliTRDpropagationLayer& layer3=*reflayers[sLayer+3];
1269       //
1270       Int_t maxn3  = layer3;
1271       for (Int_t icl3=0;icl3<maxn3;icl3++){
1272         AliTRDcluster *cl3 = layer3[icl3];
1273         if (!cl3) continue;
1274         padlength[sLayer+3] = TMath::Sqrt(cl3->GetSigmaZ2()*12.);
1275         ycl[sLayer+3] = cl3->GetY();
1276         zcl[sLayer+3] = cl3->GetZ();
1277         Float_t yymin0 = ycl[sLayer+3] - 1- kMaxPhi *(xcl[sLayer+3]-xcl[sLayer+0]);
1278         Float_t yymax0 = ycl[sLayer+3] + 1+ kMaxPhi *(xcl[sLayer+3]-xcl[sLayer+0]);
1279         Int_t   maxn0 = layer0;  //
1280         for (Int_t icl0=layer0.Find(yymin0);icl0<maxn0;icl0++){
1281           AliTRDcluster *cl0 = layer0[icl0];
1282           if (!cl0) continue;
1283           if (cl3->IsUsed()&&cl0->IsUsed()) continue;
1284           ycl[sLayer+0] = cl0->GetY();
1285           zcl[sLayer+0] = cl0->GetZ();
1286           if ( ycl[sLayer+0]>yymax0) break;
1287           Double_t tanphi   = (ycl[sLayer+3]-ycl[sLayer+0])/(xcl[sLayer+3]-xcl[sLayer+0]);
1288           if (TMath::Abs(tanphi)>kMaxPhi) continue;
1289           Double_t tantheta = (zcl[sLayer+3]-zcl[sLayer+0])/(xcl[sLayer+3]-xcl[sLayer+0]);
1290           if (TMath::Abs(tantheta)>kMaxTheta) continue;
1291           padlength[sLayer+0] = TMath::Sqrt(cl0->GetSigmaZ2()*12.);
1292           //
1293           // expected position in 1 layer
1294           Double_t y1exp = ycl[sLayer+0]+(tanphi)  *(xcl[sLayer+1]-xcl[sLayer+0]);
1295           Double_t z1exp = zcl[sLayer+0]+(tantheta)*(xcl[sLayer+1]-xcl[sLayer+0]);
1296           Float_t yymin1 = y1exp - kRoad0y-tanphi;
1297           Float_t yymax1 = y1exp + kRoad0y+tanphi;
1298           Int_t   maxn1  = layer1;  //
1299           //
1300           for (Int_t icl1=layer1.Find(yymin1);icl1<maxn1;icl1++){
1301             AliTRDcluster *cl1 = layer1[icl1];
1302             if (!cl1) continue;
1303             Int_t nusedCl = 0;
1304             if (cl3->IsUsed()) nusedCl++;
1305             if (cl0->IsUsed()) nusedCl++;
1306             if (cl1->IsUsed()) nusedCl++;
1307             if (nusedCl>1) continue;
1308             ycl[sLayer+1] = cl1->GetY();
1309             zcl[sLayer+1] = cl1->GetZ();
1310             if ( ycl[sLayer+1]>yymax1) break;
1311             if (TMath::Abs(ycl[sLayer+1]-y1exp)>kRoad0y+tanphi) continue;
1312             if (TMath::Abs(zcl[sLayer+1]-z1exp)>kRoad0z)        continue;
1313             padlength[sLayer+1] = TMath::Sqrt(cl1->GetSigmaZ2()*12.);
1314             //
1315             Double_t y2exp  = ycl[sLayer+0]+(tanphi)  *(xcl[sLayer+2]-xcl[sLayer+0])+(ycl[sLayer+1]-y1exp);
1316             Double_t z2exp  = zcl[sLayer+0]+(tantheta)*(xcl[sLayer+2]-xcl[sLayer+0]);
1317             Int_t    index2 = layer2.FindNearestCluster(y2exp,z2exp,kRoad1y,  kRoad1z);
1318             if (index2<=0) continue;
1319             AliTRDcluster *cl2 = (AliTRDcluster*)GetCluster(index2);
1320             padlength[sLayer+2] = TMath::Sqrt(cl2->GetSigmaZ2()*12.);
1321             ycl[sLayer+2] = cl2->GetY();
1322             zcl[sLayer+2] = cl2->GetZ();
1323             if (TMath::Abs(cl2->GetZ()-z2exp)>kRoad0z)        continue;
1324             //
1325             rieman.Reset();
1326             rieman.AddPoint(xcl[sLayer+0],ycl[sLayer+0],zcl[sLayer+0],1,10);
1327             rieman.AddPoint(xcl[sLayer+1],ycl[sLayer+1],zcl[sLayer+1],1,10);
1328             rieman.AddPoint(xcl[sLayer+3],ycl[sLayer+3],zcl[sLayer+3],1,10);
1329             rieman.AddPoint(xcl[sLayer+2],ycl[sLayer+2],zcl[sLayer+2],1,10);
1330             rieman.Update();
1331             //
1332             // reset fitter
1333             for (Int_t iLayer=0;iLayer<6;iLayer++){
1334               cseed[iLayer].Reset();
1335             }
1336             chi2Z =0.; chi2R=0.;
1337             for (Int_t iLayer=0;iLayer<4;iLayer++){
1338               cseed[sLayer+iLayer].fZref[0] = rieman.GetZat(xcl[sLayer+iLayer]);
1339               chi2Z += (cseed[sLayer+iLayer].fZref[0]- zcl[sLayer+iLayer])*
1340                 (cseed[sLayer+iLayer].fZref[0]- zcl[sLayer+iLayer]);
1341               cseed[sLayer+iLayer].fZref[1] = rieman.GetDZat(xcl[sLayer+iLayer]);
1342               cseed[sLayer+iLayer].fYref[0] = rieman.GetYat(xcl[sLayer+iLayer]);
1343               chi2R += (cseed[sLayer+iLayer].fYref[0]- ycl[sLayer+iLayer])*
1344                 (cseed[sLayer+iLayer].fYref[0]- ycl[sLayer+iLayer]);
1345               cseed[sLayer+iLayer].fYref[1] = rieman.GetDYat(xcl[sLayer+iLayer]);
1346             }
1347             if (TMath::Sqrt(chi2R)>1./iter) continue;
1348             if (TMath::Sqrt(chi2Z)>7./iter) continue;
1349             //
1350             //
1351             //
1352             Float_t minmax[2]={-100,100};
1353             for (Int_t iLayer=0;iLayer<4;iLayer++){
1354               Float_t max = zcl[sLayer+iLayer]+padlength[sLayer+iLayer]*0.5+1 -cseed[sLayer+iLayer].fZref[0];
1355               if (max<minmax[1]) minmax[1]=max;
1356               Float_t min = zcl[sLayer+iLayer]-padlength[sLayer+iLayer]*0.5-1 -cseed[sLayer+iLayer].fZref[0];
1357               if (min>minmax[0]) minmax[0]=min;
1358             }
1359             Bool_t isFake = kFALSE;
1360             if (cl0->GetLabel(0)!=cl3->GetLabel(0)) isFake = kTRUE;
1361             if (cl1->GetLabel(0)!=cl3->GetLabel(0)) isFake = kTRUE;
1362             if (cl2->GetLabel(0)!=cl3->GetLabel(0)) isFake = kTRUE;
1363             if (AliTRDReconstructor::StreamLevel()>0){
1364               if ((!isFake) || (icl3%10)==0 ){  //debugging print
1365                 TTreeSRedirector& cstream = *fDebugStreamer;
1366                 cstream<<"Seeds0"<<
1367                   "isFake="<<isFake<<
1368                   "Cl0.="<<cl0<<
1369                   "Cl1.="<<cl1<<
1370                   "Cl2.="<<cl2<<
1371                   "Cl3.="<<cl3<<
1372                   "Xref="<<xref<<
1373                   "X0="<<xcl[sLayer+0]<<
1374                   "X1="<<xcl[sLayer+1]<<
1375                   "X2="<<xcl[sLayer+2]<<
1376                   "X3="<<xcl[sLayer+3]<<
1377                   "Y2exp="<<y2exp<<
1378                   "Z2exp="<<z2exp<<
1379                   "Chi2R="<<chi2R<<
1380                   "Chi2Z="<<chi2Z<<
1381                   "Seed0.="<<&cseed[sLayer+0]<<
1382                   "Seed1.="<<&cseed[sLayer+1]<<
1383                   "Seed2.="<<&cseed[sLayer+2]<<
1384                   "Seed3.="<<&cseed[sLayer+3]<<
1385                   "Zmin="<<minmax[0]<<
1386                   "Zmax="<<minmax[1]<<
1387                   "\n";
1388               }
1389             }
1390
1391             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1392             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1393             //<<<<<<<<<<<<<<<<<<    FIT SEEDING PART                  <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1394             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1395             cl[sLayer+0] = cl0;
1396             cl[sLayer+1] = cl1;
1397             cl[sLayer+2] = cl2;
1398             cl[sLayer+3] = cl3;
1399             Bool_t isOK=kTRUE;
1400             for (Int_t jLayer=0;jLayer<4;jLayer++){
1401               cseed[sLayer+jLayer].fTilt = hL[sLayer+jLayer];
1402               cseed[sLayer+jLayer].fPadLength = padlength[sLayer+jLayer];
1403               cseed[sLayer+jLayer].fX0   = xcl[sLayer+jLayer];
1404               for (Int_t iter=0; iter<2; iter++){
1405                 //
1406                 // in iteration 0 we try only one pad-row
1407                 // if quality not sufficient we try 2 pad-rows - about 5% of tracks cross 2 pad-rows
1408                 //
1409                 AliTRDseed tseed = cseed[sLayer+jLayer];
1410                 Float_t    roadz  = padlength[sLayer+jLayer]*0.5;
1411                 if (iter>0) roadz = padlength[sLayer+jLayer];
1412                 //
1413                 Float_t quality =10000;
1414                 for (Int_t iTime=2;iTime<20;iTime++){
1415                   AliTRDpropagationLayer& layer = *(fTrSec[ns]->GetLayer(layers[sLayer+jLayer][1]-iTime));
1416                   Double_t dxlayer= layer.GetX()-xcl[sLayer+jLayer];
1417                   Double_t zexp   = cl[sLayer+jLayer]->GetZ() ;
1418                   if (iter>0){
1419                     // try 2 pad-rows in second iteration
1420                     zexp  = tseed.fZref[0]+ tseed.fZref[1]*dxlayer;
1421                     if (zexp>cl[sLayer+jLayer]->GetZ()) zexp = cl[sLayer+jLayer]->GetZ()+padlength[sLayer+jLayer]*0.5;
1422                     if (zexp<cl[sLayer+jLayer]->GetZ()) zexp = cl[sLayer+jLayer]->GetZ()-padlength[sLayer+jLayer]*0.5;
1423                   }
1424                   //
1425                   Double_t yexp  =  tseed.fYref[0]+
1426                     tseed.fYref[1]*dxlayer;
1427                   Int_t    index = layer.FindNearestCluster(yexp,zexp,kRoad1y, roadz);
1428                   if (index<=0) continue;
1429                   AliTRDcluster *cl = (AliTRDcluster*)GetCluster(index);
1430                   //
1431                   tseed.fIndexes[iTime]  = index;
1432                   tseed.fClusters[iTime] = cl;   // register cluster
1433                   tseed.fX[iTime] = dxlayer;     // register cluster
1434                   tseed.fY[iTime] = cl->GetY();  // register cluster
1435                   tseed.fZ[iTime] = cl->GetZ();  // register cluster
1436                 }
1437                 tseed.Update();
1438                 //count the number of clusters and distortions into quality
1439                 Float_t dangle = tseed.fYfit[1]-tseed.fYref[1];
1440                 Float_t tquality   = (18-tseed.fN2)/2. + TMath::Abs(dangle)/0.1+
1441                   TMath::Abs(tseed.fYfit[0]-tseed.fYref[0])/0.2+
1442                   2.*TMath::Abs(tseed.fMeanz-tseed.fZref[0])/padlength[jLayer];
1443                 if (iter==0 && tseed.IsOK()) {
1444                   cseed[sLayer+jLayer] = tseed;
1445                   quality = tquality;
1446                   if (tquality<5) break;
1447                 }
1448                 if (tseed.IsOK() && tquality<quality)
1449                   cseed[sLayer+jLayer] = tseed;
1450               }
1451               if (!cseed[sLayer+jLayer].IsOK()){
1452                 isOK = kFALSE;
1453                 break;
1454               }
1455               cseed[sLayer+jLayer].CookLabels();
1456               cseed[sLayer+jLayer].UpdateUsed();
1457               nusedCl+= cseed[sLayer+jLayer].fNUsed;
1458               if (nusedCl>25){
1459                 isOK = kFALSE;
1460                 break;
1461               }
1462             }
1463             //
1464             if (!isOK) continue;
1465             nclusters=0;
1466             for (Int_t iLayer=0;iLayer<4;iLayer++){
1467               if (cseed[sLayer+iLayer].IsOK()){
1468                 nclusters+=cseed[sLayer+iLayer].fN2;
1469               }
1470             }
1471             //
1472             // iteration 0
1473             rieman.Reset();
1474             for (Int_t iLayer=0;iLayer<4;iLayer++){
1475               rieman.AddPoint(xcl[sLayer+iLayer],cseed[sLayer+iLayer].fYfitR[0],
1476                               cseed[sLayer+iLayer].fZProb,1,10);
1477             }
1478             rieman.Update();
1479             //
1480             //
1481             chi2R =0; chi2Z=0;
1482             for (Int_t iLayer=0;iLayer<4;iLayer++){
1483               cseed[sLayer+iLayer].fYref[0] = rieman.GetYat(xcl[sLayer+iLayer]);
1484               chi2R += (cseed[sLayer+iLayer].fYref[0]-cseed[sLayer+iLayer].fYfitR[0])*
1485                 (cseed[sLayer+iLayer].fYref[0]-cseed[sLayer+iLayer].fYfitR[0]);
1486               cseed[sLayer+iLayer].fYref[1] = rieman.GetDYat(xcl[sLayer+iLayer]);
1487               cseed[sLayer+iLayer].fZref[0] = rieman.GetZat(xcl[sLayer+iLayer]);
1488               chi2Z += (cseed[sLayer+iLayer].fZref[0]- cseed[sLayer+iLayer].fMeanz)*
1489                 (cseed[sLayer+iLayer].fZref[0]- cseed[sLayer+iLayer].fMeanz);
1490               cseed[sLayer+iLayer].fZref[1] = rieman.GetDZat(xcl[sLayer+iLayer]);
1491             }
1492             Double_t curv = rieman.GetC();
1493             //
1494             // likelihoods
1495             //
1496             Double_t sumda =
1497               TMath::Abs(cseed[sLayer+0].fYfitR[1]- cseed[sLayer+0].fYref[1])+
1498               TMath::Abs(cseed[sLayer+1].fYfitR[1]- cseed[sLayer+1].fYref[1])+
1499               TMath::Abs(cseed[sLayer+2].fYfitR[1]- cseed[sLayer+2].fYref[1])+
1500               TMath::Abs(cseed[sLayer+3].fYfitR[1]- cseed[sLayer+3].fYref[1]);
1501             Double_t likea = TMath::Exp(-sumda*10.6);
1502             Double_t likechi2 = 0.0000000001;
1503             if (chi2R<0.5) likechi2+=TMath::Exp(-TMath::Sqrt(chi2R)*7.73);
1504             Double_t likechi2z = TMath::Exp(-chi2Z*0.088)/TMath::Exp(-chi2Z*0.019);
1505             Double_t likeN    = TMath::Exp(-(72-nclusters)*0.19);
1506             Double_t like     = likea*likechi2*likechi2z*likeN;
1507             //
1508             Double_t likePrimY = TMath::Exp(-TMath::Abs(cseed[sLayer+0].fYref[1]-130*curv)*1.9);
1509             Double_t likePrimZ = TMath::Exp(-TMath::Abs(cseed[sLayer+0].fZref[1]-
1510                                                         cseed[sLayer+0].fZref[0]/xcl[sLayer+0])*5.9);
1511             Double_t likePrim  = TMath::Max(likePrimY*likePrimZ,0.0005);
1512
1513             seedquality[registered]  = like;
1514             seedlayer[registered]    = sLayer;
1515             if (TMath::Log(0.000000000000001+like)<-15) continue;
1516             AliTRDseed seedb[6];
1517             for (Int_t iLayer=0;iLayer<6;iLayer++){
1518               seedb[iLayer] = cseed[iLayer];
1519             }
1520             //
1521             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1522             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1523             //<<<<<<<<<<<<<<<   FULL TRACK FIT PART         <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1524             //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
1525             //
1526             Int_t nlayers            = 0;
1527             Int_t nusedf             = 0;
1528             Int_t findable           = 0;
1529             //
1530             // add new layers  - avoid long extrapolation
1531             //
1532             Int_t tLayer[2]={0,0};
1533             if (sLayer==2) {tLayer[0]=1; tLayer[1]=0;}
1534             if (sLayer==1) {tLayer[0]=5; tLayer[1]=0;}
1535             if (sLayer==0) {tLayer[0]=4; tLayer[1]=5;}
1536             //
1537             for (Int_t iLayer=0;iLayer<2;iLayer++){
1538               Int_t jLayer = tLayer[iLayer];      // set tracking layer
1539               cseed[jLayer].Reset();
1540               cseed[jLayer].fTilt    = hL[jLayer];
1541               cseed[jLayer].fPadLength = padlength[jLayer];
1542               cseed[jLayer].fX0      = xcl[jLayer];
1543               // get pad length and rough cluster
1544               Int_t    indexdummy = reflayers[jLayer]->FindNearestCluster(cseed[jLayer].fYref[0],
1545                                                                           cseed[jLayer].fZref[0],kRoad2y,kRoad2z);
1546               if (indexdummy<=0) continue;
1547               AliTRDcluster *cldummy = (AliTRDcluster*)GetCluster(indexdummy);
1548               padlength[jLayer]      = TMath::Sqrt(cldummy->GetSigmaZ2()*12.);
1549             }
1550             AliTRDseed::FitRiemanTilt(cseed, kTRUE);
1551             //
1552             for (Int_t iLayer=0;iLayer<2;iLayer++){
1553               Int_t jLayer = tLayer[iLayer];      // set tracking layer
1554               if ( (jLayer==0) && !(cseed[1].IsOK())) continue;  // break not allowed
1555               if ( (jLayer==5) && !(cseed[4].IsOK())) continue;  // break not allowed
1556               Float_t  zexp  = cseed[jLayer].fZref[0];
1557               Double_t zroad =  padlength[jLayer]*0.5+1.;
1558               //
1559               //
1560               for (Int_t iter=0;iter<2;iter++){
1561                 AliTRDseed tseed = cseed[jLayer];
1562                 Float_t quality = 10000;
1563                 for (Int_t iTime=2;iTime<20;iTime++){
1564                   AliTRDpropagationLayer& layer = *(fTrSec[ns]->GetLayer(layers[jLayer][1]-iTime));
1565                   Double_t dxlayer     = layer.GetX()-xcl[jLayer];
1566                   Double_t yexp        = tseed.fYref[0]+tseed.fYref[1]*dxlayer;
1567                   Float_t  yroad       = kRoad1y;
1568                   Int_t    index = layer.FindNearestCluster(yexp,zexp, yroad, zroad);
1569                   if (index<=0) continue;
1570                   AliTRDcluster *cl = (AliTRDcluster*)GetCluster(index);
1571                   //
1572                   tseed.fIndexes[iTime]  = index;
1573                   tseed.fClusters[iTime] = cl;   // register cluster
1574                   tseed.fX[iTime] = dxlayer;     // register cluster
1575                   tseed.fY[iTime] = cl->GetY();  // register cluster
1576                   tseed.fZ[iTime] = cl->GetZ();  // register cluster
1577                 }
1578                 tseed.Update();
1579                 if (tseed.IsOK()){
1580                   Float_t dangle = tseed.fYfit[1]-tseed.fYref[1];
1581                   Float_t tquality   = (18-tseed.fN2)/2. + TMath::Abs(dangle)/0.1+
1582                     TMath::Abs(tseed.fYfit[0]-tseed.fYref[0])/0.2+
1583                     2.*TMath::Abs(tseed.fMeanz-tseed.fZref[0])/padlength[jLayer];
1584                   //
1585                   if (tquality<quality){
1586                     cseed[jLayer]=tseed;
1587                     quality = tquality;
1588                   }
1589                 }
1590                 zroad*=2.;
1591               }
1592               if ( cseed[jLayer].IsOK()){
1593                 cseed[jLayer].CookLabels();
1594                 cseed[jLayer].UpdateUsed();
1595                 nusedf+= cseed[jLayer].fNUsed;
1596                 AliTRDseed::FitRiemanTilt(cseed, kTRUE);
1597               }
1598             }
1599             //
1600             //
1601             // make copy
1602             AliTRDseed bseed[6];
1603             for (Int_t jLayer=0;jLayer<6;jLayer++){
1604               bseed[jLayer] = cseed[jLayer];
1605             }
1606             Float_t lastquality = 10000;
1607             Float_t lastchi2    = 10000;
1608             Float_t chi2        = 1000;
1609
1610             //
1611             for (Int_t iter =0; iter<4;iter++){
1612               //
1613               // sort tracklets according "quality", try to "improve" 4 worst
1614               //
1615               Float_t sumquality = 0;
1616               Float_t squality[6];
1617               Int_t   sortindexes[6];
1618               for (Int_t jLayer=0;jLayer<6;jLayer++){
1619                 if (bseed[jLayer].IsOK()){
1620                   AliTRDseed &tseed = bseed[jLayer];
1621                   Double_t zcor  =  tseed.fTilt*(tseed.fZProb-tseed.fZref[0]);
1622                   Float_t dangle = tseed.fYfit[1]-tseed.fYref[1];
1623                   Float_t tquality  = (18-tseed.fN2)/2. + TMath::Abs(dangle)/0.1+
1624                     TMath::Abs(tseed.fYfit[0]-(tseed.fYref[0]-zcor))/0.2+
1625                     2.*TMath::Abs(tseed.fMeanz-tseed.fZref[0])/padlength[jLayer];
1626                   squality[jLayer] = tquality;
1627                 }
1628                 else  squality[jLayer]=-1;
1629                 sumquality +=squality[jLayer];
1630               }
1631
1632               if (sumquality>=lastquality ||  chi2>lastchi2) break;
1633               lastquality = sumquality;
1634               lastchi2    = chi2;
1635               if (iter>0){
1636                 for (Int_t jLayer=0;jLayer<6;jLayer++){
1637                   cseed[jLayer] = bseed[jLayer];
1638                 }
1639               }
1640               TMath::Sort(6,squality,sortindexes,kFALSE);
1641               //
1642               //
1643               for (Int_t jLayer=5;jLayer>1;jLayer--){
1644                 Int_t bLayer = sortindexes[jLayer];
1645                 AliTRDseed tseed = bseed[bLayer];
1646                 for (Int_t iTime=2;iTime<20;iTime++){
1647                   AliTRDpropagationLayer& layer = *(fTrSec[ns]->GetLayer(layers[bLayer][1]-iTime));
1648                   Double_t dxlayer= layer.GetX()-xcl[bLayer];
1649                   //
1650                   Double_t zexp  =  tseed.fZref[0];
1651                   Double_t zcor  =  tseed.fTilt*(tseed.fZProb-tseed.fZref[0]);
1652                   //
1653                   Float_t  roadz = padlength[bLayer]+1;
1654                   if (TMath::Abs(tseed.fZProb-zexp)> padlength[bLayer]*0.5) {roadz = padlength[bLayer]*0.5;}
1655                   if (tseed.fZfit[1]*tseed.fZref[1]<0) {roadz = padlength[bLayer]*0.5;}
1656                   if (TMath::Abs(tseed.fZProb-zexp)<0.1*padlength[bLayer]) {
1657                     zexp = tseed.fZProb;
1658                     roadz = padlength[bLayer]*0.5;
1659                   }
1660                   //
1661                   Double_t yexp  =  tseed.fYref[0]+
1662                     tseed.fYref[1]*dxlayer-zcor;
1663                   Int_t    index = layer.FindNearestCluster(yexp,zexp,kRoad1y, roadz);
1664                   if (index<=0) continue;
1665                   AliTRDcluster *cl = (AliTRDcluster*)GetCluster(index);
1666                   //
1667                   tseed.fIndexes[iTime]  = index;
1668                   tseed.fClusters[iTime] = cl;   // register cluster
1669                   tseed.fX[iTime] = dxlayer;     // register cluster
1670                   tseed.fY[iTime] = cl->GetY();  // register cluster
1671                   tseed.fZ[iTime] = cl->GetZ();  // register cluster
1672                 }
1673                 tseed.Update();
1674                 if (tseed.IsOK()) {
1675                   Float_t dangle = tseed.fYfit[1]-tseed.fYref[1];
1676                   Double_t zcor  =  tseed.fTilt*(tseed.fZProb-tseed.fZref[0]);
1677                   //
1678                   Float_t tquality   = (18-tseed.fN2)/2. + TMath::Abs(dangle)/0.1+
1679                     TMath::Abs(tseed.fYfit[0]-(tseed.fYref[0]-zcor))/0.2+
1680                     2.*TMath::Abs(tseed.fMeanz-tseed.fZref[0])/padlength[jLayer];
1681                   //
1682                   if (tquality<squality[bLayer])
1683                     bseed[bLayer] = tseed;
1684                 }
1685               }
1686               chi2 = AliTRDseed::FitRiemanTilt(bseed, kTRUE);
1687             }
1688             //
1689             //
1690             //
1691             nclusters  = 0;
1692             nlayers    = 0;
1693             findable   = 0;
1694             for (Int_t iLayer=0;iLayer<6;iLayer++) {
1695               if (TMath::Abs(cseed[iLayer].fYref[0]/cseed[iLayer].fX0)<0.15)
1696                 findable++;
1697               if (cseed[iLayer].IsOK()){
1698                 nclusters+=cseed[iLayer].fN2;
1699                 nlayers++;
1700               }
1701             }
1702             if (nlayers<3) continue;
1703             rieman.Reset();
1704             for (Int_t iLayer=0;iLayer<6;iLayer++){
1705               if (cseed[iLayer].IsOK()) rieman.AddPoint(xcl[iLayer],cseed[iLayer].fYfitR[0],
1706                                                                    cseed[iLayer].fZProb,1,10);
1707             }
1708             rieman.Update();
1709             //
1710             chi2RF =0;
1711             chi2ZF =0;
1712             for (Int_t iLayer=0;iLayer<6;iLayer++){
1713               if (cseed[iLayer].IsOK()){
1714                 cseed[iLayer].fYref[0] = rieman.GetYat(xcl[iLayer]);
1715                 chi2RF += (cseed[iLayer].fYref[0]-cseed[iLayer].fYfitR[0])*
1716                   (cseed[iLayer].fYref[0]-cseed[iLayer].fYfitR[0]);
1717                 cseed[iLayer].fYref[1] = rieman.GetDYat(xcl[iLayer]);
1718                 cseed[iLayer].fZref[0] = rieman.GetZat(xcl[iLayer]);
1719                 chi2ZF += (cseed[iLayer].fZref[0]- cseed[iLayer].fMeanz)*
1720                   (cseed[iLayer].fZref[0]- cseed[iLayer].fMeanz);
1721                 cseed[iLayer].fZref[1] = rieman.GetDZat(xcl[iLayer]);
1722               }
1723             }
1724             chi2RF/=TMath::Max((nlayers-3.),1.);
1725             chi2ZF/=TMath::Max((nlayers-3.),1.);
1726             curv = rieman.GetC();
1727
1728             //
1729
1730             Double_t xref2    = (xcl[2]+xcl[3])*0.5;  // middle of the chamber
1731             Double_t dzmf     = rieman.GetDZat(xref2);
1732             Double_t zmf      = rieman.GetZat(xref2);
1733             //
1734             // fit hyperplane
1735             //
1736             Int_t npointsT =0;
1737             fitterTC.ClearPoints();
1738             fitterT2.ClearPoints();
1739             rieman2.Reset();
1740             for (Int_t iLayer=0; iLayer<6;iLayer++){
1741               if (!cseed[iLayer].IsOK()) continue;
1742               for (Int_t itime=0;itime<25;itime++){
1743                 if (!cseed[iLayer].fUsable[itime]) continue;
1744                 Double_t x   = cseed[iLayer].fX[itime]+cseed[iLayer].fX0-xref2;  // x relative to the midle chamber
1745                 Double_t y   = cseed[iLayer].fY[itime];
1746                 Double_t z   = cseed[iLayer].fZ[itime];
1747                 // ExB correction to the correction
1748                 // tilted rieman
1749                 //
1750                 Double_t uvt[6];
1751                 Double_t x2 = cseed[iLayer].fX[itime]+cseed[iLayer].fX0;      // global x
1752                 //
1753                 Double_t t = 1./(x2*x2+y*y);
1754                 uvt[1]  = t;    // t
1755                 uvt[0]  = 2.*x2*uvt[1];      // u
1756                 //
1757                 uvt[2]  = 2.0*hL[iLayer]*uvt[1];
1758                 uvt[3]  = 2.0*hL[iLayer]*x*uvt[1];
1759                 uvt[4]  = 2.0*(y+hL[iLayer]*z)*uvt[1];
1760                 //
1761                 Double_t error = 2*0.2*uvt[1];
1762                 fitterT2.AddPoint(uvt,uvt[4],error);
1763                 //
1764                 // constrained rieman
1765                 //
1766                 z =cseed[iLayer].fZ[itime];
1767                 uvt[0]  = 2.*x2*t;           // u
1768                 uvt[1]  = 2*hL[iLayer]*x2*uvt[1];
1769                 uvt[2]  = 2*(y+hL[iLayer]*(z-GetZ()))*t;
1770                 fitterTC.AddPoint(uvt,uvt[2],error);
1771                 //
1772                 rieman2.AddPoint(x2,y,z,1,10);
1773                 npointsT++;
1774               }
1775             }
1776             rieman2.Update();
1777             fitterTC.Eval();
1778             fitterT2.Eval();
1779             Double_t rpolz0 = fitterT2.GetParameter(3);
1780             Double_t rpolz1 = fitterT2.GetParameter(4);
1781             //
1782             // linear fitter  - not possible to make boundaries
1783             // non accept non possible z and dzdx combination
1784             //
1785             Bool_t   acceptablez =kTRUE;
1786             for (Int_t iLayer=0; iLayer<6;iLayer++){
1787               if (cseed[iLayer].IsOK()){
1788                 Double_t zT2 =  rpolz0+rpolz1*(xcl[iLayer] - xref2);
1789                 if (TMath::Abs(cseed[iLayer].fZProb-zT2)>padlength[iLayer]*0.5+1)
1790                   acceptablez = kFALSE;
1791               }
1792             }
1793             if (!acceptablez){
1794               fitterT2.FixParameter(3,zmf);
1795               fitterT2.FixParameter(4,dzmf);
1796               fitterT2.Eval();
1797               fitterT2.ReleaseParameter(3);
1798               fitterT2.ReleaseParameter(4);
1799               rpolz0 = fitterT2.GetParameter(3);
1800               rpolz1 = fitterT2.GetParameter(4);
1801             }
1802             //
1803             Double_t chi2TR = fitterT2.GetChisquare()/Float_t(npointsT);
1804             Double_t chi2TC = fitterTC.GetChisquare()/Float_t(npointsT);
1805             //
1806             Double_t polz1c = fitterTC.GetParameter(2);
1807             Double_t polz0c = polz1c*xref2;
1808             //
1809             Double_t aC     =  fitterTC.GetParameter(0);
1810             Double_t bC     =  fitterTC.GetParameter(1);
1811             Double_t cC     =  aC/TMath::Sqrt(bC*bC+1.);     // curvature
1812             //
1813             Double_t aR     =  fitterT2.GetParameter(0);
1814             Double_t bR     =  fitterT2.GetParameter(1);
1815             Double_t dR     =  fitterT2.GetParameter(2);
1816             Double_t cR     =  1+bR*bR-dR*aR;
1817             Double_t dca    =  0.;
1818             if (cR>0){
1819               dca = -dR/(TMath::Sqrt(1+bR*bR-dR*aR)+TMath::Sqrt(1+bR*bR));
1820               cR  = aR/TMath::Sqrt(cR);
1821             }
1822             //
1823             Double_t chi2ZT2=0, chi2ZTC=0;
1824             for (Int_t iLayer=0; iLayer<6;iLayer++){
1825               if (cseed[iLayer].IsOK()){
1826                 Double_t zT2 =  rpolz0+rpolz1*(xcl[iLayer] - xref2);
1827                 Double_t zTC =  polz0c+polz1c*(xcl[iLayer] - xref2);
1828                 chi2ZT2 += TMath::Abs(cseed[iLayer].fMeanz-zT2);
1829                 chi2ZTC += TMath::Abs(cseed[iLayer].fMeanz-zTC);
1830               }
1831             }
1832             chi2ZT2/=TMath::Max((nlayers-3.),1.);
1833             chi2ZTC/=TMath::Max((nlayers-3.),1.);
1834             //
1835             //
1836             //
1837             AliTRDseed::FitRiemanTilt(cseed, kTRUE);
1838             Float_t sumdaf = 0;
1839             for (Int_t iLayer=0;iLayer<6;iLayer++){
1840               if (cseed[iLayer].IsOK())
1841                 sumdaf += TMath::Abs((cseed[iLayer].fYfit[1]-cseed[iLayer].fYref[1])/cseed[iLayer].fSigmaY2);
1842             }
1843             sumdaf /= Float_t (nlayers-2.);
1844             //
1845             // likelihoods for full track
1846             //
1847             Double_t likezf      = TMath::Exp(-chi2ZF*0.14);
1848             Double_t likechi2C   = TMath::Exp(-chi2TC*0.677);
1849             Double_t likechi2TR  = TMath::Exp(-chi2TR*0.78);
1850             Double_t likeaf      = TMath::Exp(-sumdaf*3.23);
1851             seedquality2[registered] = likezf*likechi2TR*likeaf;
1852 //          Bool_t isGold = kFALSE;
1853 //
1854 //          if (nlayers == 6        && TMath::Log(0.000000001+seedquality2[index])<-5.) isGold =kTRUE;   // gold
1855 //          if (nlayers == findable && TMath::Log(0.000000001+seedquality2[index])<-4.) isGold =kTRUE;   // gold
1856 //          if (isGold &&nusedf<10){
1857 //            for (Int_t jLayer=0;jLayer<6;jLayer++){
1858 //              if ( seed[index][jLayer].IsOK()&&TMath::Abs(seed[index][jLayer].fYfit[1]-seed[index][jLayer].fYfit[1])<0.1)
1859 //                seed[index][jLayer].UseClusters();  //sign gold
1860 //            }
1861 //          }
1862             //
1863             //
1864             //
1865             Int_t index0=0;
1866             if (!cseed[0].IsOK()){
1867               index0 = 1;
1868               if (!cseed[1].IsOK()) index0 = 2;
1869             }
1870             seedparams[registered][0] = cseed[index0].fX0;
1871             seedparams[registered][1] = cseed[index0].fYref[0];
1872             seedparams[registered][2] = cseed[index0].fZref[0];
1873             seedparams[registered][5] = cR;
1874             seedparams[registered][3] = cseed[index0].fX0*cR - TMath::Sin(TMath::ATan(cseed[0].fYref[1]));
1875             seedparams[registered][4] = cseed[index0].fZref[1]/
1876               TMath::Sqrt(1+cseed[index0].fYref[1]*cseed[index0].fYref[1]);
1877             seedparams[registered][6] = ns;
1878             //
1879             //
1880             Int_t labels[12], outlab[24];
1881             Int_t nlab=0;
1882             for (Int_t iLayer=0;iLayer<6;iLayer++){
1883               if (!cseed[iLayer].IsOK()) continue;
1884               if (cseed[iLayer].fLabels[0]>=0) {
1885                 labels[nlab] = cseed[iLayer].fLabels[0];
1886                 nlab++;
1887               }
1888               if (cseed[iLayer].fLabels[1]>=0) {
1889                 labels[nlab] = cseed[iLayer].fLabels[1];
1890                 nlab++;
1891               }
1892             }
1893             Freq(nlab,labels,outlab,kFALSE);
1894             Int_t label = outlab[0];
1895             Int_t frequency  = outlab[1];
1896             for (Int_t iLayer=0;iLayer<6;iLayer++){
1897               cseed[iLayer].fFreq  = frequency;
1898               cseed[iLayer].fC     = cR;
1899               cseed[iLayer].fCC     = cC;
1900               cseed[iLayer].fChi2  = chi2TR;
1901               cseed[iLayer].fChi2Z = chi2ZF;
1902             }
1903             //
1904             if (1||(!isFake)){  //debugging print
1905               Float_t zvertex = GetZ();
1906               TTreeSRedirector& cstream = *fDebugStreamer;
1907               if (AliTRDReconstructor::StreamLevel()>0)
1908               cstream<<"Seeds1"<<
1909                 "isFake="<<isFake<<
1910                 "Vertex="<<zvertex<<
1911                 "Rieman2.="<<&rieman2<<
1912                 "Rieman.="<<&rieman<<
1913                 "Xref="<<xref<<
1914                 "X0="<<xcl[0]<<
1915                 "X1="<<xcl[1]<<
1916                 "X2="<<xcl[2]<<
1917                 "X3="<<xcl[3]<<
1918                 "X4="<<xcl[4]<<
1919                 "X5="<<xcl[5]<<
1920                 "Chi2R="<<chi2R<<
1921                 "Chi2Z="<<chi2Z<<
1922                 "Chi2RF="<<chi2RF<<                          //chi2 of trackletes on full track
1923                 "Chi2ZF="<<chi2ZF<<                          //chi2 z on tracklets on full track
1924                 "Chi2ZT2="<<chi2ZT2<<                        //chi2 z on tracklets on full track  - rieman tilt
1925                 "Chi2ZTC="<<chi2ZTC<<                        //chi2 z on tracklets on full track  - rieman tilt const
1926                 //
1927                 "Chi2TR="<<chi2TR<<                           //chi2 without vertex constrain
1928                 "Chi2TC="<<chi2TC<<                           //chi2 with    vertex constrain
1929                 "C="<<curv<<                                  // non constrained - no tilt correction
1930                 "DR="<<dR<<                                   // DR parameter          - tilt correction
1931                 "DCA="<<dca<<                                 // DCA                   - tilt correction
1932                 "CR="<<cR<<                                   // non constrained curvature - tilt correction
1933                 "CC="<<cC<<                                   // constrained curvature
1934                 "Polz0="<<polz0c<<
1935                 "Polz1="<<polz1c<<
1936                 "RPolz0="<<rpolz0<<
1937                 "RPolz1="<<rpolz1<<
1938                 "Ncl="<<nclusters<<
1939                 "Nlayers="<<nlayers<<
1940                 "NUsedS="<<nusedCl<<
1941                 "NUsed="<<nusedf<<
1942                 "Findable="<<findable<<
1943                 "Like="<<like<<
1944                 "LikePrim="<<likePrim<<
1945                 "Likechi2C="<<likechi2C<<
1946                 "Likechi2TR="<<likechi2TR<<
1947                 "Likezf="<<likezf<<
1948                 "LikeF="<<seedquality2[registered]<<
1949                 "S0.="<<&cseed[0]<<
1950                 "S1.="<<&cseed[1]<<
1951                 "S2.="<<&cseed[2]<<
1952                 "S3.="<<&cseed[3]<<
1953                 "S4.="<<&cseed[4]<<
1954                 "S5.="<<&cseed[5]<<
1955                 "SB0.="<<&seedb[0]<<
1956                 "SB1.="<<&seedb[1]<<
1957                 "SB2.="<<&seedb[2]<<
1958                 "SB3.="<<&seedb[3]<<
1959                 "SB4.="<<&seedb[4]<<
1960                 "SB5.="<<&seedb[5]<<
1961                 "Label="<<label<<
1962                 "Freq="<<frequency<<
1963                 "sLayer="<<sLayer<<
1964                 "\n";
1965             }
1966             if (registered<kMaxSeed-1) {
1967               registered++;
1968               cseed = seed[registered];
1969             }
1970           }// end of loop over layer 1
1971         }  // end of loop over layer 0
1972       }    // end of loop over layer 3
1973     }      // end of loop over seeding time bins
1974     //
1975     // choos best
1976     //
1977     TMath::Sort(registered,seedquality2,sort,kTRUE);
1978     Bool_t signedseed[kMaxSeed];
1979     for (Int_t i=0;i<registered;i++){
1980       signedseed[i]= kFALSE;
1981     }
1982     for (Int_t iter=0; iter<5; iter++){
1983       for (Int_t iseed=0;iseed<registered;iseed++){
1984         Int_t index = sort[iseed];
1985         if (signedseed[index]) continue;
1986         Int_t labelsall[1000];
1987         Int_t nlabelsall=0;
1988         Int_t naccepted=0;;
1989         Int_t sLayer = seedlayer[index];
1990         Int_t ncl   = 0;
1991         Int_t nused = 0;
1992         Int_t nlayers =0;
1993         Int_t findable   = 0;
1994         for (Int_t jLayer=0;jLayer<6;jLayer++){
1995           if (TMath::Abs(seed[index][jLayer].fYref[0]/xcl[jLayer])<0.15)
1996             findable++;
1997           if (seed[index][jLayer].IsOK()){
1998             seed[index][jLayer].UpdateUsed();
1999             ncl   +=seed[index][jLayer].fN2;
2000             nused +=seed[index][jLayer].fNUsed;
2001             nlayers++;
2002             //cooking label
2003             for (Int_t itime=0;itime<25;itime++){
2004               if (seed[index][jLayer].fUsable[itime]){
2005                 naccepted++;
2006                 for (Int_t ilab=0;ilab<3;ilab++){
2007                   Int_t tindex = seed[index][jLayer].fClusters[itime]->GetLabel(ilab);
2008                   if (tindex>=0){
2009                     labelsall[nlabelsall] = tindex;
2010                     nlabelsall++;
2011                   }
2012                 }
2013               }
2014             }
2015           }
2016         }
2017         //
2018         if (nused>30) continue;
2019         //
2020         if (iter==0){
2021           if (nlayers<6) continue;
2022           if (TMath::Log(0.000000001+seedquality2[index])<-5.) continue;   // gold
2023         }
2024         //
2025         if (iter==1){
2026           if (nlayers<findable) continue;
2027           if (TMath::Log(0.000000001+seedquality2[index])<-4.) continue;  //
2028         }
2029         //
2030         //
2031         if (iter==2){
2032           if (nlayers==findable || nlayers==6) continue;
2033           if (TMath::Log(0.000000001+seedquality2[index])<-6.) continue;
2034         }
2035         //
2036         if (iter==3){
2037           if (TMath::Log(0.000000001+seedquality2[index])<-5.) continue;
2038         }
2039         //
2040         if (iter==4){
2041           if (TMath::Log(0.000000001+seedquality2[index])-nused/(nlayers-3.)<-15.) continue;
2042         }
2043         //
2044         signedseed[index] = kTRUE;
2045         //
2046         Int_t labels[1000], outlab[1000];
2047         Int_t nlab=0;
2048         for (Int_t iLayer=0;iLayer<6;iLayer++){
2049           if (seed[index][iLayer].IsOK()){
2050             if (seed[index][iLayer].fLabels[0]>=0) {
2051               labels[nlab] = seed[index][iLayer].fLabels[0];
2052               nlab++;
2053             }
2054             if (seed[index][iLayer].fLabels[1]>=0) {
2055               labels[nlab] = seed[index][iLayer].fLabels[1];
2056               nlab++;
2057             }
2058           }
2059         }
2060         Freq(nlab,labels,outlab,kFALSE);
2061         Int_t label  = outlab[0];
2062         Int_t frequency  = outlab[1];
2063         Freq(nlabelsall,labelsall,outlab,kFALSE);
2064         Int_t label1 = outlab[0];
2065         Int_t label2 = outlab[2];
2066         Float_t fakeratio = (naccepted-outlab[1])/Float_t(naccepted);
2067         Float_t ratio = Float_t(nused)/Float_t(ncl);
2068         if (ratio<0.25){
2069           for (Int_t jLayer=0;jLayer<6;jLayer++){
2070             if ( seed[index][jLayer].IsOK()&&TMath::Abs(seed[index][jLayer].fYfit[1]-seed[index][jLayer].fYfit[1])<0.2 )
2071               seed[index][jLayer].UseClusters();  //sign gold
2072           }
2073         }
2074         //
2075         Int_t eventNr = esd->GetEventNumber();
2076         TTreeSRedirector& cstream = *fDebugStreamer;
2077         //
2078         // register seed
2079         //
2080         AliTRDtrack * track = RegisterSeed(seed[index],seedparams[index]);
2081         AliTRDtrack dummy;
2082         if (!track) track=&dummy;
2083         else{
2084           AliESDtrack esdtrack;
2085           esdtrack.UpdateTrackParams(track, AliESDtrack::kTRDout);
2086           esdtrack.SetLabel(label);
2087           esd->AddTrack(&esdtrack);
2088           TTreeSRedirector& cstream = *fDebugStreamer;
2089           if (AliTRDReconstructor::StreamLevel()>0)
2090             cstream<<"Tracks"<<
2091               "EventNr="<<eventNr<<
2092               "ESD.="<<&esdtrack<<
2093               "trd.="<<track<<
2094               "trdback.="<<track<<
2095               "\n";
2096         }
2097         if (AliTRDReconstructor::StreamLevel()>0)
2098           cstream<<"Seeds2"<<
2099           "Iter="<<iter<<
2100           "Track.="<<track<<
2101           "Like="<<seedquality[index]<<
2102           "LikeF="<<seedquality2[index]<<
2103           "S0.="<<&seed[index][0]<<
2104           "S1.="<<&seed[index][1]<<
2105           "S2.="<<&seed[index][2]<<
2106           "S3.="<<&seed[index][3]<<
2107           "S4.="<<&seed[index][4]<<
2108           "S5.="<<&seed[index][5]<<
2109           "Label="<<label<<
2110           "Label1="<<label1<<
2111           "Label2="<<label2<<
2112           "FakeRatio="<<fakeratio<<
2113           "Freq="<<frequency<<
2114           "Ncl="<<ncl<<
2115           "Nlayers="<<nlayers<<
2116           "Findable="<<findable<<
2117           "NUsed="<<nused<<
2118           "sLayer="<<sLayer<<
2119           "EventNr="<<eventNr<<
2120           "\n";
2121       }
2122     }
2123   }        // end of loop over sectors
2124
2125   delete [] pseed;
2126
2127 }
2128
2129 //_____________________________________________________________________________
2130 Int_t AliTRDtracker::ReadClusters(TObjArray *array, TTree *ClusterTree) const
2131 {
2132   //
2133   // Reads AliTRDclusters (option >= 0) or AliTRDrecPoints (option < 0)
2134   // from the file. The names of the cluster tree and branches
2135   // should match the ones used in AliTRDclusterizer::WriteClusters()
2136   //
2137
2138   Int_t nsize = Int_t(ClusterTree->GetTotBytes()/(sizeof(AliTRDcluster)));
2139   TObjArray *clusterArray = new TObjArray(nsize+1000);
2140
2141   TBranch *branch=ClusterTree->GetBranch("TRDcluster");
2142   if (!branch) {
2143     Error("ReadClusters","Can't get the branch !");
2144     return 1;
2145   }
2146   branch->SetAddress(&clusterArray);
2147
2148   Int_t nEntries = (Int_t) ClusterTree->GetEntries();
2149   //  printf("found %d entries in %s.\n",nEntries,ClusterTree->GetName());
2150
2151   // Loop through all entries in the tree
2152   Int_t nbytes = 0;
2153   AliTRDcluster *c = 0;
2154   //  printf("\n");
2155   for (Int_t iEntry = 0; iEntry < nEntries; iEntry++) {
2156
2157     // Import the tree
2158     nbytes += ClusterTree->GetEvent(iEntry);
2159
2160     // Get the number of points in the detector
2161     Int_t nCluster = clusterArray->GetEntriesFast();
2162 //    printf("\r Read %d clusters from entry %d", nCluster, iEntry);
2163
2164     // Loop through all TRD digits
2165     for (Int_t iCluster = 0; iCluster < nCluster; iCluster++) {
2166       c = (AliTRDcluster*)clusterArray->UncheckedAt(iCluster);
2167       AliTRDcluster *co = c;
2168       array->AddLast(co);
2169       //      delete clusterArray->RemoveAt(iCluster);
2170       clusterArray->RemoveAt(iCluster);
2171     }
2172   }
2173 //   cout<<"Allocated"<<nsize<<"\tLoaded"<<array->GetEntriesFast()<<"\n";
2174
2175   delete clusterArray;
2176
2177   return 0;
2178
2179 }
2180
2181 //_____________________________________________________________________________
2182 Bool_t AliTRDtracker::GetTrackPoint(Int_t index, AliTrackPoint& p) const
2183 {
2184   //
2185   // Get track space point with index i
2186   // Origin: C.Cheshkov
2187   //
2188
2189   AliTRDcluster *cl = (AliTRDcluster*)fClusters->UncheckedAt(index);
2190   Int_t  idet = cl->GetDetector();
2191   Int_t  isector = fGeom->GetSector(idet);
2192   Int_t  ichamber= fGeom->GetChamber(idet);
2193   Int_t  iplan   = fGeom->GetPlane(idet);
2194   Double_t local[3];
2195   local[0]=GetX(isector,iplan,cl->GetLocalTimeBin());
2196   local[1]=cl->GetY();
2197   local[2]=cl->GetZ();
2198   Double_t global[3];
2199   fGeom->RotateBack(idet,local,global);
2200   p.SetXYZ(global[0],global[1],global[2]);
2201   AliAlignObj::ELayerID iLayer = AliAlignObj::kTRD1;
2202   switch (iplan) {
2203   case 0:
2204     iLayer = AliAlignObj::kTRD1;
2205     break;
2206   case 1:
2207     iLayer = AliAlignObj::kTRD2;
2208     break;
2209   case 2:
2210     iLayer = AliAlignObj::kTRD3;
2211     break;
2212   case 3:
2213     iLayer = AliAlignObj::kTRD4;
2214     break;
2215   case 4:
2216     iLayer = AliAlignObj::kTRD5;
2217     break;
2218   case 5:
2219     iLayer = AliAlignObj::kTRD6;
2220     break;
2221   };
2222   Int_t modId = isector*fGeom->Ncham()+ichamber;
2223   UShort_t volid = AliAlignObj::LayerToVolUID(iLayer,modId);
2224   p.SetVolumeID(volid);
2225
2226   return kTRUE;
2227
2228 }
2229
2230 //_____________________________________________________________________________
2231 void AliTRDtracker::CookLabel(AliKalmanTrack* pt, Float_t wrong) const
2232 {
2233   //
2234   // This cooks a label. Mmmmh, smells good...
2235   //
2236
2237   Int_t label=123456789, index, i, j;
2238   Int_t ncl=pt->GetNumberOfClusters();
2239   const Int_t kRange = fTrSec[0]->GetOuterTimeBin()+1;
2240
2241   Bool_t labelAdded;
2242
2243   //  Int_t s[kRange][2];
2244   Int_t **s = new Int_t* [kRange];
2245   for (i=0; i<kRange; i++) {
2246     s[i] = new Int_t[2];
2247   }
2248   for (i=0; i<kRange; i++) {
2249     s[i][0]=-1;
2250     s[i][1]=0;
2251   }
2252
2253   Int_t t0,t1,t2;
2254   for (i=0; i<ncl; i++) {
2255     index=pt->GetClusterIndex(i);
2256     AliTRDcluster *c=(AliTRDcluster*)fClusters->UncheckedAt(index);
2257     t0=c->GetLabel(0);
2258     t1=c->GetLabel(1);
2259     t2=c->GetLabel(2);
2260   }
2261
2262   for (i=0; i<ncl; i++) {
2263     index=pt->GetClusterIndex(i);
2264     AliTRDcluster *c=(AliTRDcluster*)fClusters->UncheckedAt(index);
2265     for (Int_t k=0; k<3; k++) {
2266       label=c->GetLabel(k);
2267       labelAdded=kFALSE; j=0;
2268       if (label >= 0) {
2269         while ( (!labelAdded) && ( j < kRange ) ) {
2270           if (s[j][0]==label || s[j][1]==0) {
2271             s[j][0]=label;
2272             s[j][1]=s[j][1]+1;
2273             labelAdded=kTRUE;
2274           }
2275           j++;
2276         }
2277       }
2278     }
2279   }
2280
2281   Int_t max=0;
2282   label = -123456789;
2283
2284   for (i=0; i<kRange; i++) {
2285     if (s[i][1]>max) {
2286       max=s[i][1]; label=s[i][0];
2287     }
2288   }
2289
2290   for (i=0; i<kRange; i++) {
2291     delete []s[i];
2292   }
2293
2294   delete []s;
2295
2296   if ((1.- Float_t(max)/ncl) > wrong) label=-label;
2297
2298   pt->SetLabel(label);
2299
2300 }
2301
2302 //_____________________________________________________________________________
2303 void AliTRDtracker::UseClusters(const AliKalmanTrack* t, Int_t from) const
2304 {
2305   //
2306   // Use clusters, but don't abuse them!
2307   //
2308
2309   const Float_t kmaxchi2 =18;
2310   const Float_t kmincl   =10;
2311   AliTRDtrack * track  = (AliTRDtrack*)t;
2312   //
2313   Int_t ncl=t->GetNumberOfClusters();
2314   for (Int_t i=from; i<ncl; i++) {
2315     Int_t index = t->GetClusterIndex(i);
2316     AliTRDcluster *c=(AliTRDcluster*)fClusters->UncheckedAt(index);
2317     //
2318     Int_t iplane = fGeom->GetPlane(c->GetDetector());
2319     if (track->fTracklets[iplane].GetChi2()>kmaxchi2) continue;
2320     if (track->fTracklets[iplane].GetN()<kmincl) continue;
2321     if (!(c->IsUsed())) c->Use();
2322   }
2323
2324 }
2325
2326 //_____________________________________________________________________________
2327 Double_t AliTRDtracker::ExpectedSigmaY2(Double_t , Double_t , Double_t ) const
2328 {
2329   //
2330   // Parametrised "expected" error of the cluster reconstruction in Y
2331   //
2332
2333   Double_t s = 0.08 * 0.08;
2334   return s;
2335
2336 }
2337
2338 //_____________________________________________________________________________
2339 Double_t AliTRDtracker::ExpectedSigmaZ2(Double_t , Double_t ) const
2340 {
2341   //
2342   // Parametrised "expected" error of the cluster reconstruction in Z
2343   //
2344
2345   Double_t s = 9 * 9 /12.;
2346   return s;
2347
2348 }
2349
2350 //_____________________________________________________________________________
2351 Double_t AliTRDtracker::GetX(Int_t sector, Int_t plane, Int_t localTB) const
2352 {
2353   //
2354   // Returns radial position which corresponds to time bin <localTB>
2355   // in tracking sector <sector> and plane <plane>
2356   //
2357
2358   Int_t index = fTrSec[sector]->CookTimeBinIndex(plane, localTB);
2359   Int_t pl = fTrSec[sector]->GetLayerNumber(index);
2360   return fTrSec[sector]->GetLayer(pl)->GetX();
2361
2362 }
2363
2364 //_____________________________________________________________________________
2365 AliTRDtracker::AliTRDpropagationLayer
2366              ::AliTRDpropagationLayer(Double_t x, Double_t dx, Double_t rho
2367                                     , Double_t radLength, Int_t tbIndex, Int_t plane)
2368 {
2369   //
2370   // AliTRDpropagationLayer constructor
2371   //
2372
2373   fN = 0; fX = x; fdX = dx; fRho = rho; fX0 = radLength;
2374   fClusters = NULL; fIndex = NULL; fTimeBinIndex = tbIndex;
2375   fPlane = plane;
2376
2377   for(Int_t i=0; i < (Int_t) kZones; i++) {
2378     fZc[i]=0; fZmax[i] = 0;
2379   }
2380
2381   fYmax = 0;
2382
2383   if(fTimeBinIndex >= 0) {
2384     fClusters = new AliTRDcluster*[kMaxClusterPerTimeBin];
2385     fIndex = new UInt_t[kMaxClusterPerTimeBin];
2386   }
2387
2388   for (Int_t i=0;i<5;i++) fIsHole[i] = kFALSE;
2389   fHole = kFALSE;
2390   fHoleZc = 0;
2391   fHoleZmax = 0;
2392   fHoleYc = 0;
2393   fHoleYmax = 0;
2394   fHoleRho = 0;
2395   fHoleX0 = 0;
2396
2397 }
2398
2399 //_____________________________________________________________________________
2400 void AliTRDtracker::AliTRDpropagationLayer
2401                   ::SetHole(Double_t Zmax, Double_t Ymax, Double_t rho
2402                           , Double_t radLength, Double_t Yc, Double_t Zc)
2403 {
2404   //
2405   // Sets hole in the layer
2406   //
2407
2408   fHole = kTRUE;
2409   fHoleZc = Zc;
2410   fHoleZmax = Zmax;
2411   fHoleYc = Yc;
2412   fHoleYmax = Ymax;
2413   fHoleRho = rho;
2414   fHoleX0 = radLength;
2415
2416 }
2417
2418 //_____________________________________________________________________________
2419 AliTRDtracker::AliTRDtrackingSector
2420              ::AliTRDtrackingSector(AliTRDgeometry* geo, Int_t gs)
2421 {
2422   //
2423   // AliTRDtrackingSector Constructor
2424   //
2425
2426   AliTRDpadPlane *padPlane = 0;
2427
2428   fGeom = geo;
2429   fGeomSector = gs;
2430   fN = 0;
2431   //
2432   // get holes description from geometry
2433   Bool_t holes[AliTRDgeometry::kNcham];
2434   //printf("sector\t%d\t",gs);
2435   for (Int_t icham=0; icham<AliTRDgeometry::kNcham;icham++){
2436     holes[icham] = fGeom->IsHole(0,icham,gs);
2437     //printf("%d",holes[icham]);
2438   }
2439   //printf("\n");
2440
2441   for(UInt_t i=0; i < kMaxTimeBinIndex; i++) fTimeBinIndex[i] = -1;
2442
2443
2444   AliTRDpropagationLayer* ppl;
2445
2446   Double_t x, dx, rho, radLength;
2447   //  Int_t    steps;
2448
2449   // add layers for each of the planes
2450   Double_t dxAmp = (Double_t) fGeom->CamHght();   // Amplification region
2451   //Double_t dxDrift = (Double_t) fGeom->CdrHght(); // Drift region
2452
2453   Int_t    tbIndex;
2454   const Int_t  kNchambers = AliTRDgeometry::Ncham();
2455   Double_t  ymax = 0;
2456   Double_t ymaxsensitive=0;
2457   Double_t *zc = new Double_t[kNchambers];
2458   Double_t *zmax = new Double_t[kNchambers];
2459   Double_t *zmaxsensitive = new Double_t[kNchambers];
2460
2461   AliTRDCommonParam* commonParam = AliTRDCommonParam::Instance();
2462   if (!commonParam)
2463   {
2464     printf("<AliTRDtracker::AliTRDtrackingSector::AliTRDtrackingSector> ");
2465     printf("Could not get common params\n");
2466     return;
2467   }
2468
2469   for(Int_t plane = 0; plane < AliTRDgeometry::Nplan(); plane++) {
2470
2471     ymax          = fGeom->GetChamberWidth(plane)/2.;
2472     // Modidified for new pad plane class, 22.04.05 (C.B.)
2473     padPlane = commonParam->GetPadPlane(plane,0);
2474     ymaxsensitive = (padPlane->GetColSize(1)*padPlane->GetNcols()-4)/2.;
2475     for(Int_t ch = 0; ch < kNchambers; ch++) {
2476       zmax[ch] = fGeom->GetChamberLength(plane,ch)/2;
2477       //
2478       // Modidified for new pad plane class, 22.04.05 (C.B.)
2479       Float_t pad = padPlane->GetRowSize(1);
2480       Float_t row0 = commonParam->GetRow0(plane,ch,0);
2481       Int_t nPads = commonParam->GetRowMax(plane,ch,0);
2482       zmaxsensitive[ch] = Float_t(nPads)*pad/2.;
2483       zc[ch] = -(pad * nPads)/2 + row0;
2484     }
2485
2486     dx  = AliTRDcalibDB::Instance()->GetVdrift(0,0,0)
2487         / AliTRDcalibDB::Instance()->GetSamplingFrequency();
2488     rho = 0.00295 * 0.85; radLength = 11.0;
2489
2490     Double_t x0 = (Double_t) AliTRDgeometry::GetTime0(plane);
2491     //Double_t xbottom = x0 - dxDrift;
2492     //Double_t xtop = x0 + dxAmp;
2493     //
2494     Int_t nTimeBins =  AliTRDcalibDB::Instance()->GetNumberOfTimeBins();
2495     for (Int_t iTime = 0; iTime<nTimeBins; iTime++){
2496       Double_t xlayer  = iTime*dx - dxAmp;
2497       //if (xlayer<0) xlayer=dxAmp/2.;
2498       x = x0 - xlayer;
2499       //
2500       tbIndex = CookTimeBinIndex(plane, iTime);
2501       ppl = new AliTRDpropagationLayer(x,dx,rho,radLength,tbIndex, plane);
2502       ppl->SetYmax(ymax,ymaxsensitive);
2503       ppl->SetZ(zc, zmax, zmaxsensitive);
2504       ppl->SetHoles(holes);
2505       InsertLayer(ppl);
2506     }
2507   }
2508
2509   MapTimeBinLayers();
2510   delete [] zc;
2511   delete [] zmax;
2512   delete [] zmaxsensitive;
2513
2514 }
2515
2516 //_____________________________________________________________________________
2517 Int_t  AliTRDtracker::AliTRDtrackingSector
2518                     ::CookTimeBinIndex(Int_t plane, Int_t localTB) const
2519 {
2520   //
2521   // depending on the digitization parameters calculates "global"
2522   // time bin index for timebin <localTB> in plane <plane>
2523   //
2524   //
2525
2526   Int_t tbPerPlane = AliTRDcalibDB::Instance()->GetNumberOfTimeBins();
2527   Int_t gtb = (plane+1) * tbPerPlane - localTB -1;
2528   if (localTB<0) return -1;
2529   if (gtb<0)     return -1;
2530
2531   return gtb;
2532
2533 }
2534
2535 //_____________________________________________________________________________
2536 void AliTRDtracker::AliTRDtrackingSector
2537                   ::MapTimeBinLayers()
2538 {
2539   //
2540   // For all sensitive time bins sets corresponding layer index
2541   // in the array fTimeBins
2542   //
2543
2544   Int_t index;
2545
2546   for(Int_t i = 0; i < fN; i++) {
2547     index = fLayers[i]->GetTimeBinIndex();
2548
2549     //    printf("gtb %d -> pl %d -> x %f \n", index, i, fLayers[i]->GetX());
2550
2551     if(index < 0) continue;
2552     if(index >= (Int_t) kMaxTimeBinIndex) {
2553       printf("*** AliTRDtracker::MapTimeBinLayers: \n");
2554       printf("    index %d exceeds allowed maximum of %d!\n",
2555              index, kMaxTimeBinIndex-1);
2556       continue;
2557     }
2558     fTimeBinIndex[index] = i;
2559   }
2560
2561 }
2562
2563 //_____________________________________________________________________________
2564 Int_t AliTRDtracker::AliTRDtrackingSector
2565                    ::GetLayerNumber(Double_t x) const
2566 {
2567   //
2568   // Returns the number of time bin which in radial position is closest to <x>
2569   //
2570
2571   if(x >= fLayers[fN-1]->GetX()) return fN-1;
2572   if(x <= fLayers[0]->GetX()) return 0;
2573
2574   Int_t b=0, e=fN-1, m=(b+e)/2;
2575   for (; b<e; m=(b+e)/2) {
2576     if (x > fLayers[m]->GetX()) b=m+1;
2577     else e=m;
2578   }
2579   if(TMath::Abs(x - fLayers[m]->GetX()) >
2580      TMath::Abs(x - fLayers[m+1]->GetX())) return m+1;
2581
2582   else return m;
2583
2584 }
2585
2586 //_____________________________________________________________________________
2587 Int_t AliTRDtracker::AliTRDtrackingSector
2588                    ::GetInnerTimeBin() const
2589 {
2590   //
2591   // Returns number of the innermost SENSITIVE propagation layer
2592   //
2593
2594   return GetLayerNumber(0);
2595
2596 }
2597
2598 //_____________________________________________________________________________
2599 Int_t AliTRDtracker::AliTRDtrackingSector
2600                    ::GetOuterTimeBin() const
2601 {
2602   //
2603   // Returns number of the outermost SENSITIVE time bin
2604   //
2605
2606   return GetLayerNumber(GetNumberOfTimeBins() - 1);
2607
2608 }
2609
2610 //_____________________________________________________________________________
2611 Int_t AliTRDtracker::AliTRDtrackingSector
2612                    ::GetNumberOfTimeBins() const
2613 {
2614   //
2615   // Returns number of SENSITIVE time bins
2616   //
2617
2618   Int_t tb, layer;
2619   for(tb = kMaxTimeBinIndex-1; tb >=0; tb--) {
2620     layer = GetLayerNumber(tb);
2621     if(layer>=0) break;
2622   }
2623
2624   return tb+1;
2625
2626 }
2627
2628 //_____________________________________________________________________________
2629 void AliTRDtracker::AliTRDtrackingSector
2630                   ::InsertLayer(AliTRDpropagationLayer* pl)
2631 {
2632   //
2633   // Insert layer <pl> in fLayers array.
2634   // Layers are sorted according to X coordinate.
2635   //
2636
2637   if ( fN == ((Int_t) kMaxLayersPerSector)) {
2638     printf("AliTRDtrackingSector::InsertLayer(): Too many layers !\n");
2639     return;
2640   }
2641   if (fN==0) {fLayers[fN++] = pl; return;}
2642   Int_t i=Find(pl->GetX());
2643
2644   memmove(fLayers+i+1 ,fLayers+i,(fN-i)*sizeof(AliTRDpropagationLayer*));
2645   fLayers[i]=pl; fN++;
2646
2647 }
2648
2649 //_____________________________________________________________________________
2650 Int_t AliTRDtracker::AliTRDtrackingSector
2651                    ::Find(Double_t x) const
2652 {
2653   //
2654   // Returns index of the propagation layer nearest to X
2655   //
2656
2657   if (x <= fLayers[0]->GetX()) return 0;
2658   if (x > fLayers[fN-1]->GetX()) return fN;
2659   Int_t b=0, e=fN-1, m=(b+e)/2;
2660   for (; b<e; m=(b+e)/2) {
2661     if (x > fLayers[m]->GetX()) b=m+1;
2662     else e=m;
2663   }
2664
2665   return m;
2666
2667 }
2668
2669 //_____________________________________________________________________________
2670 void AliTRDtracker::AliTRDpropagationLayer
2671                   ::SetZ(Double_t* center, Double_t *w, Double_t *wsensitive )
2672 {
2673   //
2674   // set centers and the width of sectors
2675   //
2676
2677   for (Int_t icham=0;icham< AliTRDgeometry::kNcham;icham++){
2678     fZc[icham] = center[icham];
2679     fZmax[icham] = w[icham];
2680     fZmaxSensitive[icham] = wsensitive[icham];
2681     // printf("chamber\t%d\tzc\t%f\tzmax\t%f\tzsens\t%f\n",icham,fZc[icham],fZmax[icham],fZmaxSensitive[icham]);
2682   }
2683
2684 }
2685
2686 //_____________________________________________________________________________
2687 void AliTRDtracker::AliTRDpropagationLayer::SetHoles(Bool_t *holes)
2688 {
2689   //
2690   // set centers and the width of sectors
2691   //
2692
2693   fHole = kFALSE;
2694   for (Int_t icham=0;icham< AliTRDgeometry::kNcham;icham++){
2695     fIsHole[icham] = holes[icham];
2696     if (holes[icham]) fHole = kTRUE;
2697   }
2698
2699 }
2700
2701 //_____________________________________________________________________________
2702 void AliTRDtracker::AliTRDpropagationLayer
2703                   ::InsertCluster(AliTRDcluster* c, UInt_t index)
2704 {
2705   //
2706   // Insert cluster in cluster array.
2707   // Clusters are sorted according to Y coordinate.
2708   //
2709
2710   if(fTimeBinIndex < 0) {
2711     printf("*** attempt to insert cluster into non-sensitive time bin!\n");
2712     return;
2713   }
2714
2715   if (fN== (Int_t) kMaxClusterPerTimeBin) {
2716     printf("AliTRDpropagationLayer::InsertCluster(): Too many clusters !\n");
2717     return;
2718   }
2719   if (fN==0) {fIndex[0]=index; fClusters[fN++]=c; return;}
2720   Int_t i=Find(c->GetY());
2721   memmove(fClusters+i+1 ,fClusters+i,(fN-i)*sizeof(AliTRDcluster*));
2722   memmove(fIndex   +i+1 ,fIndex   +i,(fN-i)*sizeof(UInt_t));
2723   fIndex[i]=index; fClusters[i]=c; fN++;
2724
2725 }
2726
2727 //_____________________________________________________________________________
2728 Int_t AliTRDtracker::AliTRDpropagationLayer::Find(Float_t y) const
2729 {
2730   //
2731   // Returns index of the cluster nearest in Y
2732   //
2733
2734   if (fN<=0) return 0;
2735   if (y <= fClusters[0]->GetY()) return 0;
2736   if (y > fClusters[fN-1]->GetY()) return fN;
2737   Int_t b=0, e=fN-1, m=(b+e)/2;
2738   for (; b<e; m=(b+e)/2) {
2739     if (y > fClusters[m]->GetY()) b=m+1;
2740     else e=m;
2741   }
2742
2743   return m;
2744
2745 }
2746
2747 //_____________________________________________________________________________
2748 Int_t AliTRDtracker::AliTRDpropagationLayer
2749                    ::FindNearestCluster(Float_t y, Float_t z, Float_t maxroad
2750                                       , Float_t maxroadz) const
2751 {
2752   //
2753   // Returns index of the cluster nearest to the given y,z
2754   //
2755
2756   Int_t index = -1;
2757   Int_t maxn = fN;
2758   Float_t mindist = maxroad;
2759   //
2760   for (Int_t i=Find(y-maxroad); i<maxn; i++) {
2761     AliTRDcluster* c=(AliTRDcluster*)(fClusters[i]);
2762     Float_t ycl = c->GetY();
2763     //
2764     if (ycl > y+maxroad) break;
2765     if (TMath::Abs(c->GetZ()-z) > maxroadz) continue;
2766     if (TMath::Abs(ycl-y)<mindist){
2767       mindist = TMath::Abs(ycl-y);
2768       index = fIndex[i];
2769     }
2770   }
2771
2772   return index;
2773
2774 }
2775
2776 //_____________________________________________________________________________
2777 Double_t AliTRDtracker::GetTiltFactor(const AliTRDcluster* c)
2778 {
2779   //
2780   // Returns correction factor for tilted pads geometry
2781   //
2782
2783   Int_t det = c->GetDetector();
2784   Int_t plane = fGeom->GetPlane(det);
2785   AliTRDpadPlane *padPlane = AliTRDCommonParam::Instance()->GetPadPlane(plane,0);
2786   Double_t h01 = TMath::Tan(-TMath::Pi() / 180.0 * padPlane->GetTiltingAngle());
2787
2788   if(fNoTilt) h01 = 0;
2789
2790   return h01;
2791
2792 }
2793
2794 //_____________________________________________________________________________
2795 void AliTRDtracker::CookdEdxTimBin(AliTRDtrack& TRDtrack)
2796 {
2797   //
2798   // *** ADDED TO GET MORE INFORMATION FOR TRD PID  ---- PS
2799   // This is setting fdEdxPlane and fTimBinPlane
2800   // Sums up the charge in each plane for track TRDtrack and also get the
2801   // Time bin for Max. Cluster
2802   // Prashant Shukla (shukla@physi.uni-heidelberg.de)
2803   //
2804
2805   Double_t  clscharge[AliESDtrack::kNPlane][AliESDtrack::kNSlice];
2806   Double_t  maxclscharge[AliESDtrack::kNPlane];
2807   Int_t     nCluster[AliESDtrack::kNPlane][AliESDtrack::kNSlice];
2808   Int_t     timebin[AliESDtrack::kNPlane];
2809
2810   //Initialization of cluster charge per plane.
2811   for (Int_t iPlane = 0; iPlane < AliESDtrack::kNPlane; iPlane++) {
2812     for (Int_t iSlice = 0; iSlice < AliESDtrack::kNSlice; iSlice++) {
2813       clscharge[iPlane][iSlice] = 0.0;
2814       nCluster[iPlane][iSlice] = 0;
2815     }
2816   }
2817
2818   //Initialization of cluster charge per plane.
2819   for (Int_t iPlane = 0; iPlane < AliESDtrack::kNPlane; iPlane++) {
2820     timebin[iPlane] = -1;
2821     maxclscharge[iPlane] = 0.0;
2822   }
2823
2824   // Loop through all clusters associated to track TRDtrack
2825   Int_t nClus = TRDtrack.GetNumberOfClusters();  // from Kalmantrack
2826   for (Int_t iClus = 0; iClus < nClus; iClus++) {
2827     Double_t charge = TRDtrack.GetClusterdQdl(iClus);
2828     Int_t index = TRDtrack.GetClusterIndex(iClus);
2829     AliTRDcluster *pTRDcluster = (AliTRDcluster *) GetCluster(index);
2830     if (!pTRDcluster) continue;
2831     Int_t tb = pTRDcluster->GetLocalTimeBin();
2832     if (!tb) continue;
2833     Int_t detector = pTRDcluster->GetDetector();
2834     Int_t iPlane   = fGeom->GetPlane(detector);
2835     Int_t iSlice = tb*AliESDtrack::kNSlice/AliTRDtrack::kNtimeBins;
2836     clscharge[iPlane][iSlice] = clscharge[iPlane][iSlice]+charge;
2837     if(charge > maxclscharge[iPlane]) {
2838       maxclscharge[iPlane] = charge;
2839       timebin[iPlane] = tb;
2840     }
2841     nCluster[iPlane][iSlice]++;
2842   } // end of loop over cluster
2843
2844   // Setting the fdEdxPlane and fTimBinPlane variabales
2845   Double_t totalCharge = 0;
2846
2847   for (Int_t iPlane = 0; iPlane < AliESDtrack::kNPlane; iPlane++) {
2848     for (Int_t iSlice = 0; iSlice < AliESDtrack::kNSlice; iSlice++) {
2849       if (nCluster[iPlane][iSlice]) clscharge[iPlane][iSlice] /= nCluster[iPlane][iSlice];
2850       TRDtrack.SetPIDsignals(clscharge[iPlane][iSlice], iPlane, iSlice);
2851       totalCharge= totalCharge+clscharge[iPlane][iSlice];
2852     }
2853     TRDtrack.SetPIDTimBin(timebin[iPlane], iPlane);
2854   }
2855
2856   //  Int_t i;
2857   //  Int_t nc=TRDtrack.GetNumberOfClusters();
2858   //  Float_t dedx=0;
2859   //  for (i=0; i<nc; i++) dedx += TRDtrack.GetClusterdQdl(i);
2860   //  dedx /= nc;
2861   //  for (Int_t iPlane = 0; iPlane < kNPlane; iPlane++) {
2862   //    TRDtrack.SetPIDsignals(dedx, iPlane);
2863   //    TRDtrack.SetPIDTimBin(timbin[iPlane], iPlane);
2864   //  }
2865
2866 }
2867
2868 //_____________________________________________________________________________
2869 Int_t AliTRDtracker::FindClusters(Int_t sector, Int_t t0, Int_t t1
2870                                 , AliTRDtrack * track
2871                                 , Int_t *clusters,AliTRDtracklet&tracklet)
2872 {
2873   //
2874   //
2875   // Try to find nearest clusters to the track in timebins from t0 to t1
2876   //
2877   //
2878   //
2879   // correction coeficients   - depends on TRD parameters  - to be changed according it
2880   //
2881
2882   Double_t x[100],yt[100],zt[100];
2883   Double_t xmean=0;   //reference x
2884   Double_t dz[10][100],dy[10][100];
2885   Float_t zmean[100], nmean[100];
2886   Int_t    clfound=0;
2887   Int_t    indexes[10][100];    // indexes of the clusters in the road
2888   AliTRDcluster *cl[10][100];   // pointers to the clusters in the road
2889   Int_t    best[10][100];       // index of best matching cluster
2890   //
2891   //
2892
2893   for (Int_t it=0;it<100; it++){
2894     x[it]=0;
2895     yt[it]=0;
2896     zt[it]=0;
2897     clusters[it]=-2;
2898     zmean[it]=0;
2899     nmean[it]=0;
2900     //
2901     for (Int_t ih=0;ih<10;ih++){
2902       indexes[ih][it]=-2;              //reset indexes1
2903       cl[ih][it]=0;
2904       dz[ih][it]=-100;
2905       dy[ih][it]=-100;
2906       best[ih][it]=0;
2907     }
2908   }
2909   //
2910   Double_t x0 = track->GetX();
2911   Double_t sigmaz = TMath::Sqrt(TMath::Abs(track->GetSigmaZ2()));
2912   Int_t nall=0;
2913   Int_t nfound=0;
2914   Double_t h01 =0;
2915   Int_t plane =-1;
2916   Int_t detector =-1;
2917   Float_t padlength=0;
2918   AliTRDtrack track2(*track);
2919   Float_t snpy = track->GetSnp();
2920   Float_t tany = TMath::Sqrt(snpy*snpy/(1.-snpy*snpy));
2921   if (snpy<0) tany*=-1;
2922   //
2923   Double_t sy2=ExpectedSigmaY2(x0,track->GetTgl(),track->GetPt());
2924   Double_t sz2=ExpectedSigmaZ2(x0,track->GetTgl());
2925   Double_t road = 15.*sqrt(track->GetSigmaY2() + sy2);
2926   if (road>6.) road=6.;
2927
2928   //
2929   for (Int_t it=0;it<t1-t0;it++){
2930     Double_t maxChi2[2]={fgkMaxChi2,fgkMaxChi2};
2931     AliTRDpropagationLayer& timeBin=*(fTrSec[sector]->GetLayer(it+t0));
2932     if (timeBin==0) continue;  // no indexes1
2933     Int_t maxn = timeBin;
2934     x[it] = timeBin.GetX();
2935     track2.PropagateTo(x[it]);
2936     yt[it] = track2.GetY();
2937     zt[it] = track2.GetZ();
2938
2939     Double_t  y=yt[it],z=zt[it];
2940     Double_t chi2 =1000000;
2941     nall++;
2942     //
2943     // find 2 nearest cluster at given time bin
2944     //
2945     //
2946     for (Int_t i=timeBin.Find(y-road); i<maxn; i++) {
2947       AliTRDcluster* c=(AliTRDcluster*)(timeBin[i]);
2948       h01 = GetTiltFactor(c);
2949       if (plane<0){
2950         Int_t det = c->GetDetector();
2951         plane = fGeom->GetPlane(det);
2952         padlength = TMath::Sqrt(c->GetSigmaZ2()*12.);
2953       }
2954       //      if (c->GetLocalTimeBin()==0) continue;
2955       if (c->GetY() > y+road) break;
2956       if((c->GetZ()-z)*(c->GetZ()-z) > 12. * sz2) continue;
2957
2958       Double_t dist = TMath::Abs(c->GetZ()-z);
2959       if (dist> (0.5*padlength+6.*sigmaz)) continue;   // 6 sigma boundary cut
2960       Double_t cost = 0;
2961       //
2962       if (dist> (0.5*padlength-sigmaz)){   //  sigma boundary cost function
2963         cost =  (dist-0.5*padlength)/(2.*sigmaz);
2964         if (cost>-1) cost= (cost+1.)*(cost+1.);
2965         else cost=0;
2966       }
2967       //      Int_t label = TMath::Abs(track->GetLabel());
2968       //      if (c->GetLabel(0)!=label && c->GetLabel(1)!=label&&c->GetLabel(2)!=label) continue;
2969       chi2=track2.GetPredictedChi2(c,h01)+cost;
2970       //
2971       clfound++;
2972       if (chi2 > maxChi2[1]) continue;
2973       detector = c->GetDetector();
2974
2975       for (Int_t ih=2;ih<9; ih++){  //store the clusters in the road
2976         if (cl[ih][it]==0){
2977           cl[ih][it] = c;
2978           indexes[ih][it] =timeBin.GetIndex(i);   // index - 9 - reserved for outliers
2979           break;
2980         }
2981       }
2982       //
2983       if (chi2 <maxChi2[0]){
2984         maxChi2[1]     = maxChi2[0];
2985         maxChi2[0]     = chi2;
2986         indexes[1][it] = indexes[0][it];
2987         cl[1][it]      = cl[0][it];
2988         indexes[0][it] = timeBin.GetIndex(i);
2989         cl[0][it]      = c;
2990         continue;
2991       }
2992       maxChi2[1]=chi2;
2993       cl[1][it] = c;
2994       indexes[1][it] =timeBin.GetIndex(i);
2995     }
2996     if (cl[0][it]){
2997       nfound++;
2998       xmean += x[it];
2999     }
3000   }
3001   //
3002   if (nfound<4) return 0;
3003   xmean /=Float_t(nfound);     // middle x
3004   track2.PropagateTo(xmean);   // propagate track to the center
3005   //
3006   // choose one of the variants
3007   //
3008   Int_t changes[10];
3009   Float_t sumz      = 0;
3010   Float_t sum       = 0;
3011   Double_t sumdy    = 0;
3012   Double_t sumdy2   = 0;
3013   Double_t sumx     = 0;
3014   Double_t sumxy    = 0;
3015   Double_t sumx2    = 0;
3016   Double_t mpads    = 0;
3017   //
3018   Int_t   ngood[10];
3019   Int_t   nbad[10];
3020   //
3021   Double_t meanz[10];
3022   Double_t moffset[10];    // mean offset
3023   Double_t mean[10];       // mean value
3024   Double_t angle[10];      // angle
3025   //
3026   Double_t smoffset[10];   // sigma of mean offset
3027   Double_t smean[10];      // sigma of mean value
3028   Double_t sangle[10];     // sigma of angle
3029   Double_t smeanangle[10]; // correlation
3030   //
3031   Double_t sigmas[10];
3032   Double_t tchi2s[10];      // chi2s for tracklet
3033
3034   for (Int_t it=0;it<10;it++) {
3035
3036     ngood[it] = 0;
3037     nbad[it] = 0;
3038   //
3039     meanz[it] = 0;
3040     moffset[it] = 0;    // mean offset
3041     mean[it] = 0;       // mean value
3042     angle[it] = 0;      // angle
3043   //
3044     smoffset[it] = 1e10;   // sigma of mean offset
3045     smean[it] = 1e10;      // sigma of mean value
3046     sangle[it] = 1e10;     // sigma of angle
3047     smeanangle[it] = 0; // correlation
3048   //
3049     sigmas[it] = 1e10;
3050     tchi2s[it] = 1e10;      // chi2s for tracklet
3051
3052   }
3053
3054   //
3055   // calculate zmean
3056   //
3057   for (Int_t it=0;it<t1-t0;it++){
3058     if (!cl[0][it]) continue;
3059     for (Int_t dt=-3;dt<=3;dt++){
3060       if (it+dt<0) continue;
3061       if (it+dt>t1-t0) continue;
3062       if (!cl[0][it+dt]) continue;
3063       zmean[it]+=cl[0][it+dt]->GetZ();
3064       nmean[it]+=1.;
3065     }
3066     zmean[it]/=nmean[it];
3067   }
3068   //
3069   for (Int_t it=0; it<t1-t0;it++){
3070     best[0][it]=0;
3071     for (Int_t ih=0;ih<10;ih++){
3072       dz[ih][it]=-100;
3073       dy[ih][it]=-100;
3074       if (!cl[ih][it]) continue;
3075       Double_t  xcluster = cl[ih][it]->GetX();
3076       Double_t ytrack,ztrack;
3077       track2.GetProlongation(xcluster, ytrack, ztrack );
3078       dz[ih][it]  = cl[ih][it]->GetZ()- ztrack;                               // calculate distance from track  in z
3079       dy[ih][it]  = cl[ih][it]->GetY()+ dz[ih][it]*h01  -ytrack;     //                                in y
3080     }
3081     // minimize changes
3082     if (!cl[0][it]) continue;
3083     if (TMath::Abs(cl[0][it]->GetZ()-zmean[it])> padlength*0.8 &&cl[1][it])
3084       if (TMath::Abs(cl[1][it]->GetZ()-zmean[it])< padlength*0.5){
3085         best[0][it]=1;
3086       }
3087   }
3088   //
3089   // iterative choosing of "best path"
3090   //
3091   //
3092   Int_t label = TMath::Abs(track->GetLabel());
3093   Int_t bestiter=0;
3094   //
3095   for (Int_t iter=0;iter<9;iter++){
3096     //
3097     changes[iter]= 0;
3098     sumz      = 0; sum=0; sumdy=0;sumdy2=0;sumx=0;sumx2=0;sumxy=0;mpads=0; ngood[iter]=0; nbad[iter]=0;
3099     // linear fit
3100     for (Int_t it=0;it<t1-t0;it++){
3101       if (!cl[best[iter][it]][it]) continue;
3102       //calculates pad-row changes
3103       Double_t zbefore= cl[best[iter][it]][it]->GetZ();
3104       Double_t zafter = cl[best[iter][it]][it]->GetZ();
3105       for (Int_t itd = it-1; itd>=0;itd--) {
3106         if (cl[best[iter][itd]][itd]) {
3107           zbefore= cl[best[iter][itd]][itd]->GetZ();
3108           break;
3109         }
3110       }
3111       for (Int_t itd = it+1; itd<t1-t0;itd++) {
3112         if (cl[best[iter][itd]][itd]) {
3113           zafter= cl[best[iter][itd]][itd]->GetZ();
3114           break;
3115         }
3116       }
3117       if (TMath::Abs(cl[best[iter][it]][it]->GetZ()-zbefore)>0.1&&TMath::Abs(cl[best[iter][it]][it]->GetZ()-zafter)>0.1) changes[iter]++;
3118       //
3119       Double_t dx = x[it]-xmean;  // distance to reference x
3120       sumz += cl[best[iter][it]][it]->GetZ();
3121       sum++;
3122       sumdy += dy[best[iter][it]][it];
3123       sumdy2+= dy[best[iter][it]][it]*dy[best[iter][it]][it];
3124       sumx  += dx;
3125       sumx2 += dx*dx;
3126       sumxy  += dx*dy[best[iter][it]][it];
3127       mpads += cl[best[iter][it]][it]->GetNPads();
3128       if (cl[best[iter][it]][it]->GetLabel(0)==label || cl[best[iter][it]][it]->GetLabel(1)==label||cl[best[iter][it]][it]->GetLabel(2)==label){
3129         ngood[iter]++;
3130       }
3131       else{
3132         nbad[iter]++;
3133       }
3134     }
3135     //
3136     // calculates line parameters
3137     //
3138     Double_t det  = sum*sumx2-sumx*sumx;
3139     angle[iter]   = (sum*sumxy-sumx*sumdy)/det;
3140     mean[iter]    = (sumx2*sumdy-sumx*sumxy)/det;
3141     meanz[iter]   = sumz/sum;
3142     moffset[iter] = sumdy/sum;
3143     mpads        /= sum;                         // mean number of pads
3144     //
3145     //
3146     Double_t  sigma2 = 0;   // normalized residuals - for line fit
3147     Double_t  sigma1 = 0;   // normalized residuals - constant fit
3148     //
3149     for (Int_t it=0;it<t1-t0;it++){
3150       if (!cl[best[iter][it]][it]) continue;
3151       Double_t dx = x[it]-xmean;
3152       Double_t ytr = mean[iter]+angle[iter]*dx;
3153       sigma2 += (dy[best[iter][it]][it]-ytr)*(dy[best[iter][it]][it]-ytr);
3154       sigma1 +=  (dy[best[iter][it]][it]-moffset[iter])*(dy[best[iter][it]][it]-moffset[iter]);
3155       sum++;
3156     }
3157     sigma2      /=(sum-2);                    // normalized residuals
3158     sigma1      /=(sum-1);                    // normalized residuals
3159     //
3160     smean[iter]       = sigma2*(sumx2/det);   // estimated error2 of mean
3161     sangle[iter]      = sigma2*(sum/det);     // estimated error2 of angle
3162     smeanangle[iter]  = sigma2*(-sumx/det);   // correlation
3163     //
3164     //
3165     sigmas[iter]  = TMath::Sqrt(sigma1);      //
3166     smoffset[iter]= (sigma1/sum)+0.01*0.01;             // sigma of mean offset + unisochronity sigma
3167     //
3168     // iterative choosing of "better path"
3169     //
3170     for (Int_t it=0;it<t1-t0;it++){
3171       if (!cl[best[iter][it]][it]) continue;
3172       //
3173       Double_t sigmatr2 = smoffset[iter]+0.5*tany*tany;             //add unisochronity + angular effect contribution
3174       Double_t sweight  = 1./sigmatr2+1./track->GetSigmaY2();
3175       Double_t weighty  = (moffset[iter]/sigmatr2)/sweight;         // weighted mean
3176       Double_t sigmacl  = TMath::Sqrt(sigma1*sigma1+track->GetSigmaY2());   //
3177       Double_t mindist=100000;
3178       Int_t ihbest=0;
3179       for (Int_t ih=0;ih<10;ih++){
3180         if (!cl[ih][it]) break;
3181         Double_t dist2 = (dy[ih][it]-weighty)/sigmacl;
3182         dist2*=dist2;    //chi2 distance
3183         if (dist2<mindist){
3184           mindist = dist2;
3185           ihbest =ih;
3186         }
3187       }
3188       best[iter+1][it]=ihbest;
3189     }
3190     //
3191     //  update best hypothesy if better chi2 according tracklet position and angle
3192     //
3193     Double_t sy2 = smean[iter]  + track->GetSigmaY2();
3194     Double_t sa2 = sangle[iter] + track->fCee;
3195     Double_t say = track->fCey;
3196     //    Double_t chi20 = mean[bestiter]*mean[bestiter]/sy2+angle[bestiter]*angle[bestiter]/sa2;
3197     // Double_t chi21 = mean[iter]*mean[iter]/sy2+angle[iter]*angle[iter]/sa2;
3198
3199     Double_t detchi    = sy2*sa2-say*say;
3200     Double_t invers[3] = {sa2/detchi, sy2/detchi, -say/detchi};   //inverse value of covariance matrix
3201
3202     Double_t chi20 = mean[bestiter]*mean[bestiter]*invers[0]+angle[bestiter]*angle[bestiter]*invers[1]+
3203       2.*mean[bestiter]*angle[bestiter]*invers[2];
3204     Double_t chi21 = mean[iter]*mean[iter]*invers[0]+angle[iter]*angle[iter]*invers[1]+
3205       2*mean[iter]*angle[iter]*invers[2];
3206     tchi2s[iter] =chi21;
3207     //
3208     if (changes[iter]<=changes[bestiter] && chi21<chi20) {
3209       bestiter =iter;
3210     }
3211   }
3212   //
3213   //set clusters
3214   //
3215   Double_t sigma2 = sigmas[0];   // choose as sigma  from 0 iteration
3216   Short_t maxpos    = -1;
3217   Float_t maxcharge =  0;
3218   Short_t maxpos4    = -1;
3219   Float_t maxcharge4 =  0;
3220   Short_t maxpos5    = -1;
3221   Float_t maxcharge5 =  0;
3222
3223   //if (tchi2s[bestiter]>25.) sigma2*=tchi2s[bestiter]/25.;
3224   //if (tchi2s[bestiter]>25.) sigma2=1000.;  // dont'accept
3225
3226   Double_t exB = AliTRDcalibDB::Instance()->GetOmegaTau(AliTRDcalibDB::Instance()->GetVdrift(0,0,0));
3227   Double_t expectederr = sigma2*sigma2+0.01*0.01;
3228   if (mpads>3.5) expectederr  +=   (mpads-3.5)*0.04;
3229   if (changes[bestiter]>1) expectederr+=   changes[bestiter]*0.01;
3230   expectederr+=(0.03*(tany-exB)*(tany-exB))*15;
3231   //  if (tchi2s[bestiter]>18.) expectederr*= tchi2s[bestiter]/18.;
3232   //expectederr+=10000;
3233   for (Int_t it=0;it<t1-t0;it++){
3234     if (!cl[best[bestiter][it]][it]) continue;
3235     cl[best[bestiter][it]][it]->SetSigmaY2(expectederr);  // set cluster error
3236     if (!cl[best[bestiter][it]][it]->IsUsed()){
3237       cl[best[bestiter][it]][it]->SetY( cl[best[bestiter][it]][it]->GetY());
3238       //      cl[best[bestiter][it]][it]->Use();
3239     }
3240     //
3241     //  time bins with maximal charge
3242     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge){
3243       maxcharge = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3244       maxpos = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3245     }
3246
3247     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge4){
3248       if (cl[best[bestiter][it]][it]->GetLocalTimeBin()>=4){
3249         maxcharge4 = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3250         maxpos4 = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3251       }
3252     }
3253     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge5){
3254       if (cl[best[bestiter][it]][it]->GetLocalTimeBin()>=5){
3255         maxcharge5 = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3256         maxpos5 = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3257       }
3258     }
3259     //
3260     //  time bins with maximal charge
3261     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge){
3262       maxcharge = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3263       maxpos = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3264     }
3265
3266     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge4){
3267       if (cl[best[bestiter][it]][it]->GetLocalTimeBin()>=4){
3268         maxcharge4 = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3269         maxpos4 = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3270       }
3271     }
3272     if (TMath::Abs(cl[best[bestiter][it]][it]->GetQ())> maxcharge5){
3273       if (cl[best[bestiter][it]][it]->GetLocalTimeBin()>=5){
3274         maxcharge5 = TMath::Abs(cl[best[bestiter][it]][it]->GetQ());
3275         maxpos5 = cl[best[bestiter][it]][it]->GetLocalTimeBin();
3276       }
3277     }
3278     clusters[it+t0] = indexes[best[bestiter][it]][it];
3279     //if (cl[best[bestiter][it]][it]->GetLocalTimeBin()>4 && cl[best[bestiter][it]][it]->GetLocalTimeBin()<18) clusters[it+t0] = indexes[best[bestiter][it]][it];    //Test
3280   }
3281   //
3282   // set tracklet parameters
3283   //
3284   Double_t trackleterr2 = smoffset[bestiter]+0.01*0.01;
3285   if (mpads>3.5) trackleterr2  +=   (mpads-3.5)*0.04;
3286   trackleterr2+=   changes[bestiter]*0.01;
3287   trackleterr2*=   TMath::Max(14.-nfound,1.);
3288   trackleterr2+=   0.2*(tany-exB)*(tany-exB);
3289   //
3290   tracklet.Set(xmean, track2.GetY()+moffset[bestiter], meanz[bestiter], track2.GetAlpha(), trackleterr2);  //set tracklet parameters
3291   tracklet.SetTilt(h01);
3292   tracklet.SetP0(mean[bestiter]);
3293   tracklet.SetP1(angle[bestiter]);
3294   tracklet.SetN(nfound);
3295   tracklet.SetNCross(changes[bestiter]);
3296   tracklet.SetPlane(plane);
3297   tracklet.SetSigma2(expectederr);
3298   tracklet.SetChi2(tchi2s[bestiter]);
3299   tracklet.SetMaxPos(maxpos,maxpos4,maxpos5);
3300   track->fTracklets[plane] = tracklet;
3301   track->fNWrong+=nbad[0];
3302   //
3303   // Debuging part
3304   //
3305   TClonesArray array0("AliTRDcluster");
3306   TClonesArray array1("AliTRDcluster");
3307   array0.ExpandCreateFast(t1-t0+1);
3308   array1.ExpandCreateFast(t1-t0+1);
3309   TTreeSRedirector& cstream = *fDebugStreamer;
3310   AliTRDcluster dummy;
3311   Double_t dy0[100];
3312   Double_t dyb[100];
3313
3314   for (Int_t it=0;it<t1-t0;it++){
3315     dy0[it] = dy[0][it];
3316     dyb[it] = dy[best[bestiter][it]][it];
3317     if(cl[0][it]) {
3318       new(array0[it]) AliTRDcluster(*cl[0][it]);
3319     }
3320     else{
3321       new(array0[it]) AliTRDcluster(dummy);
3322     }
3323     if(cl[best[bestiter][it]][it]) {
3324       new(array1[it]) AliTRDcluster(*cl[best[bestiter][it]][it]);
3325     }
3326     else{
3327       new(array1[it]) AliTRDcluster(dummy);
3328     }
3329   }
3330   TGraph graph0(t1-t0,x,dy0);
3331   TGraph graph1(t1-t0,x,dyb);
3332   TGraph graphy(t1-t0,x,yt);
3333   TGraph graphz(t1-t0,x,zt);
3334   //
3335   //
3336   if (AliTRDReconstructor::StreamLevel()>0)
3337   cstream<<"tracklet"<<
3338     "track.="<<track<<                                       // track parameters
3339     "tany="<<tany<<                                          // tangent of the local track angle
3340     "xmean="<<xmean<<                                        // xmean - reference x of tracklet
3341     "tilt="<<h01<<                                           // tilt angle
3342     "nall="<<nall<<                                          // number of foundable clusters
3343     "nfound="<<nfound<<                                      // number of found clusters
3344     "clfound="<<clfound<<                                    // total number of found clusters in road
3345     "mpads="<<mpads<<                                        // mean number of pads per cluster
3346     "plane="<<plane<<                                        // plane number
3347     "detector="<<detector<<                                  // detector number
3348     "road="<<road<<                                          // the width of the used road
3349     "graph0.="<<&graph0<<                                    // x - y = dy for closest cluster
3350     "graph1.="<<&graph1<<                                    // x - y = dy for second closest cluster
3351     "graphy.="<<&graphy<<                                    // y position of the track
3352     "graphz.="<<&graphz<<                                    // z position of the track
3353     //    "fCl.="<<&array0<<                                       // closest cluster
3354     //"fCl2.="<<&array1<<                                      // second closest cluster
3355     "maxpos="<<maxpos<<                                      // maximal charge postion
3356     "maxcharge="<<maxcharge<<                                // maximal charge
3357     "maxpos4="<<maxpos4<<                                    // maximal charge postion - after bin 4
3358     "maxcharge4="<<maxcharge4<<                              // maximal charge         - after bin 4
3359     "maxpos5="<<maxpos5<<                                    // maximal charge postion - after bin 5
3360     "maxcharge5="<<maxcharge5<<                              // maximal charge         - after bin 5
3361     //
3362     "bestiter="<<bestiter<<                                  // best iteration number
3363     "tracklet.="<<&tracklet<<                                // corrspond to the best iteration
3364     "tchi20="<<tchi2s[0]<<                                   // chi2 of cluster in the 0 iteration
3365     "tchi2b="<<tchi2s[bestiter]<<                            // chi2 of cluster in the best  iteration
3366     "sigmas0="<<sigmas[0]<<                                  // residuals sigma
3367     "sigmasb="<<sigmas[bestiter]<<                           // residulas sigma
3368     //
3369     "ngood0="<<ngood[0]<<                                    // number of good clusters in 0 iteration
3370     "nbad0="<<nbad[0]<<                                      // number of bad clusters in 0 iteration
3371     "ngoodb="<<ngood[bestiter]<<                             //                        in  best iteration
3372     "nbadb="<<nbad[bestiter]<<                               //                        in  best iteration
3373     //
3374     "changes0="<<changes[0]<<                                // changes of pardrows in iteration number 0
3375     "changesb="<<changes[bestiter]<<                         // changes of pardrows in best iteration
3376     //
3377     "moffset0="<<moffset[0]<<                                // offset fixing angle in iter=0
3378     "smoffset0="<<smoffset[0]<<                              // sigma of offset fixing angle in iter=0
3379     "moffsetb="<<moffset[bestiter]<<                         // offset fixing angle in iter=best
3380     "smoffsetb="<<smoffset[bestiter]<<                       // sigma of offset fixing angle in iter=best
3381     //
3382     "mean0="<<mean[0]<<                                      // mean dy in iter=0;
3383     "smean0="<<smean[0]<<                                    // sigma of mean dy in iter=0
3384     "meanb="<<mean[bestiter]<<                               // mean dy in iter=best
3385     "smeanb="<<smean[bestiter]<<                             // sigma of mean dy in iter=best
3386     //
3387     "angle0="<<angle[0]<<                                    // angle deviation in the iteration number 0
3388     "sangle0="<<sangle[0]<<                                  // sigma of angular deviation in iteration number 0
3389     "angleb="<<angle[bestiter]<<                             // angle deviation in the best iteration
3390     "sangleb="<<sangle[bestiter]<<                           // sigma of angle deviation in the best iteration
3391     //
3392     "expectederr="<<expectederr<<                            // expected error of cluster position
3393     "\n";
3394   //
3395   //
3396   return nfound;
3397
3398 }
3399
3400 //_____________________________________________________________________________
3401 Int_t AliTRDtracker::Freq(Int_t n, const Int_t *inlist
3402                         , Int_t *outlist, Bool_t down)
3403 {
3404   //
3405   //  Sort eleements according occurancy
3406   //  The size of output array has is 2*n
3407   //
3408
3409   Int_t * sindexS = new Int_t[n];     // temp array for sorting
3410   Int_t * sindexF = new Int_t[2*n];
3411   for (Int_t i=0;i<n;i++) sindexF[i]=0;
3412   //
3413   TMath::Sort(n,inlist, sindexS, down);
3414   Int_t last      = inlist[sindexS[0]];
3415   Int_t val       = last;
3416   sindexF[0]      = 1;
3417   sindexF[0+n]    = last;
3418   Int_t countPos  = 0;
3419   //
3420   //  find frequency
3421   for(Int_t i=1;i<n; i++){
3422     val = inlist[sindexS[i]];
3423     if (last == val)   sindexF[countPos]++;
3424     else{
3425       countPos++;
3426       sindexF[countPos+n] = val;
3427       sindexF[countPos]++;
3428       last =val;
3429     }
3430   }
3431   if (last==val) countPos++;
3432   // sort according frequency
3433   TMath::Sort(countPos, sindexF, sindexS, kTRUE);
3434   for (Int_t i=0;i<countPos;i++){
3435     outlist[2*i  ] = sindexF[sindexS[i]+n];
3436     outlist[2*i+1] = sindexF[sindexS[i]];
3437   }
3438   delete [] sindexS;
3439   delete [] sindexF;
3440
3441   return countPos;
3442
3443 }
3444
3445 //_____________________________________________________________________________
3446 AliTRDtrack *AliTRDtracker::RegisterSeed(AliTRDseed * seeds, Double_t * params)
3447 {
3448   //
3449   // Register a seed
3450   //
3451   Double_t alpha=AliTRDgeometry::GetAlpha();
3452   Double_t shift=AliTRDgeometry::GetAlpha()/2.;
3453   Double_t c[15];
3454   c[0] = 0.2;
3455   c[1] = 0  ; c[2] = 2;
3456   c[3] = 0  ; c[4] = 0; c[5] = 0.02;
3457   c[6] = 0  ; c[7] = 0; c[8] = 0;      c[9] = 0.1;
3458   c[10] = 0  ; c[11] = 0; c[12] = 0;   c[13] = 0.0; c[14] = params[5]*params[5]*0.01;
3459   //
3460   Int_t index =0;
3461   AliTRDcluster *cl =0;
3462   for (Int_t ilayer=0;ilayer<6;ilayer++){
3463     if (seeds[ilayer].IsOK()){
3464       for (Int_t itime=22;itime>0;itime--){
3465         if (seeds[ilayer].fIndexes[itime]>0){
3466           index = seeds[ilayer].fIndexes[itime];
3467           cl = seeds[ilayer].fClusters[itime];
3468           break;
3469         }
3470       }
3471     }
3472     if (index>0) break;
3473   }
3474   if (cl==0) return 0;
3475   AliTRDtrack * track  = new AliTRDtrack(cl,index,&params[1],c, params[0],params[6]*alpha+shift);
3476   track->PropagateTo(params[0]-5.);
3477   track->ResetCovariance(1);
3478   //
3479   Int_t rc=FollowBackProlongation(*track);
3480   if (rc<30) {
3481     delete track;
3482     track =0;
3483   }else{
3484     track->CookdEdx();
3485     CookdEdxTimBin(*track);
3486     CookLabel(track, 0.9);
3487   }
3488
3489   return track;
3490
3491 }