TRD/AliTRDtrackerV1.cxx

   1
   2 /**************************************************************************
   3  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   4  *                                                                        *
   5  * Author: The ALICE Off-line Project.                                    *
   6  * Contributors are mentioned in the code where appropriate.              *
   7  *                                                                        *
   8  * Permission to use, copy, modify and distribute this software and its   *
   9  * documentation strictly for non-commercial purposes is hereby granted   *
  10  * without fee, provided that the above copyright notice appears in all   *
  11  * copies and that both the copyright notice and this permission notice   *
  12  * appear in the supporting documentation. The authors make no claims     *
  13  * about the suitability of this software for any purpose. It is          *
  14  * provided "as is" without express or implied warranty.                  *
  15  **************************************************************************/
  16
  17 /* $Id$ */
  18
  19 ///////////////////////////////////////////////////////////////////////////////
  20 //                                                                           //
  21 //  Track finder                                                             //
  22 //                                                                           //
  23 //  Authors:                                                                 //
  24 //    Alex Bercuci <A.Bercuci@gsi.de>                                        //
  25 //    Markus Fasel <M.Fasel@gsi.de>                                          //
  26 //                                                                           //
  27 ///////////////////////////////////////////////////////////////////////////////
  28
  29 // #include <Riostream.h>
  30 // #include <stdio.h>
  31 // #include <string.h>
  32
  33 #include <TBranch.h>
  34 #include <TDirectory.h>
  35 #include <TLinearFitter.h>
  36 #include <TTree.h>
  37 #include <TClonesArray.h>
  38 #include <TTreeStream.h>
  39
  40 #include "AliLog.h"
  41 #include "AliESDEvent.h"
  42 #include "AliGeomManager.h"
  43 #include "AliRieman.h"
  44 #include "AliTrackPointArray.h"
  45
  46 #include "AliTRDgeometry.h"
  47 #include "AliTRDpadPlane.h"
  48 #include "AliTRDcalibDB.h"
  49 #include "AliTRDReconstructor.h"
  50 #include "AliTRDCalibraFillHisto.h"
  51 #include "AliTRDrecoParam.h"
  52
  53 #include "AliTRDcluster.h"
  54 #include "AliTRDseedV1.h"
  55 #include "AliTRDtrackV1.h"
  56 #include "AliTRDtrackerV1.h"
  57 #include "AliTRDtrackerDebug.h"
  58 #include "AliTRDtrackingChamber.h"
  59 #include "AliTRDchamberTimeBin.h"
  60
  61
  62
  63 ClassImp(AliTRDtrackerV1)
  64
  65
  66 const  Float_t  AliTRDtrackerV1::fgkMinClustersInTrack =  0.5;  //
  67 const  Float_t  AliTRDtrackerV1::fgkLabelFraction      =  0.8;  //
  68 const  Double_t AliTRDtrackerV1::fgkMaxChi2            = 12.0;  //
  69 const  Double_t AliTRDtrackerV1::fgkMaxSnp             =  0.95; // Maximum local sine of the azimuthal angle
  70 const  Double_t AliTRDtrackerV1::fgkMaxStep            =  2.0;  // Maximal step size in propagation
  71 Double_t AliTRDtrackerV1::fgTopologicQA[kNConfigs] = {
  72                 0.1112, 0.1112, 0.1112, 0.0786, 0.0786,
  73                 0.0786, 0.0786, 0.0579, 0.0579, 0.0474,
  74                 0.0474, 0.0408, 0.0335, 0.0335, 0.0335
  75 };
  76 Int_t AliTRDtrackerV1::fgNTimeBins = 0;
  77 TTreeSRedirector *AliTRDtrackerV1::fgDebugStreamer = 0x0;
  78 AliRieman* AliTRDtrackerV1::fgRieman = 0x0;
  79 TLinearFitter* AliTRDtrackerV1::fgTiltedRieman = 0x0;
  80 TLinearFitter* AliTRDtrackerV1::fgTiltedRiemanConstrained = 0x0;
  81
  82 //____________________________________________________________________
  83 AliTRDtrackerV1::AliTRDtrackerV1()
  84   :AliTracker()
  85   ,fGeom(new AliTRDgeometry())
  86   ,fClusters(0x0)
  87   ,fTracklets(0x0)
  88   ,fTracks(0x0)
  89   ,fSieveSeeding(0)
  90 {
  91   //
  92   // Default constructor.
  93   //
  94   if (!AliTRDcalibDB::Instance()) {
  95     AliFatal("Could not get calibration object");
  96   }
  97   fgNTimeBins = AliTRDcalibDB::Instance()->GetNumberOfTimeBins();
  98
  99         for (Int_t isector = 0; isector < AliTRDgeometry::kNsect; isector++) new(&fTrSec[isector]) AliTRDtrackingSector(fGeom, isector);
 100
 101   if(AliTRDReconstructor::StreamLevel() > 1){
 102                 TDirectory *savedir = gDirectory;
 103                 fgDebugStreamer    = new TTreeSRedirector("TRD.TrackerDebug.root");
 104         savedir->cd();
 105         }
 106 }
 107
 108 //____________________________________________________________________
 109 AliTRDtrackerV1::~AliTRDtrackerV1()
 110 {
 111   //
 112   // Destructor
 113   //
 114
 115         if(fgDebugStreamer) delete fgDebugStreamer;
 116         if(fgRieman) delete fgRieman;
 117         if(fgTiltedRieman) delete fgTiltedRieman;
 118         if(fgTiltedRiemanConstrained) delete fgTiltedRiemanConstrained;
 119         if(fTracks) {fTracks->Delete(); delete fTracks;}
 120         if(fTracklets) {fTracklets->Delete(); delete fTracklets;}
 121         if(fClusters) {fClusters->Delete(); delete fClusters;}
 122         if(fGeom) delete fGeom;
 123 }
 124
 125 //____________________________________________________________________
 126 Int_t AliTRDtrackerV1::Clusters2Tracks(AliESDEvent *esd)
 127 {
 128   //
 129   // Steering stand alone tracking for full TRD detector
 130   //
 131   // Parameters :
 132   //   esd     : The ESD event. On output it contains
 133   //             the ESD tracks found in TRD.
 134   //
 135   // Output :
 136   //   Number of tracks found in the TRD detector.
 137   //
 138   // Detailed description
 139   // 1. Launch individual SM trackers.
 140   //    See AliTRDtrackerV1::Clusters2TracksSM() for details.
 141   //
 142
 143         if(!AliTRDReconstructor::RecoParam()){
 144                 AliError("Reconstruction configuration not initialized. Call first AliTRDReconstructor::SetRecoParam().");
 145                 return 0;
 146         }
 147
 148         //AliInfo("Start Track Finder ...");
 149         Int_t ntracks = 0;
 150         for(int ism=0; ism<AliTRDgeometry::kNsect; ism++){
 151 //      for(int ism=1; ism<2; ism++){
 152                         //AliInfo(Form("Processing supermodule %i ...", ism));
 153                         ntracks += Clusters2TracksSM(ism, esd);
 154         }
 155   AliInfo(Form("Number of found tracks : %d", ntracks));
 156         return ntracks;
 157 }
 158
 159
 160 //_____________________________________________________________________________
 161 Bool_t AliTRDtrackerV1::GetTrackPoint(Int_t index, AliTrackPoint &p) const
 162 {
 163         //AliInfo(Form("Asking for tracklet %d", index));
 164
 165         if(index<0) return kFALSE;
 166         AliTRDseedV1 *tracklet = 0x0;
 167         if(!(tracklet = (AliTRDseedV1*)fTracklets->UncheckedAt(index))) return kFALSE;
 168
 169         // get detector for this tracklet
 170         AliTRDcluster *cl = 0x0;
 171         Int_t ic = 0; do; while(!(cl = tracklet->GetClusters(ic++)));
 172         Int_t  idet     = cl->GetDetector();
 173
 174         Double_t local[3];
 175         local[0] = tracklet->GetX0();
 176         local[1] = tracklet->GetYfit(0);
 177         local[2] = tracklet->GetZfit(0);
 178         Double_t global[3];
 179         fGeom->RotateBack(idet, local, global);
 180         p.SetXYZ(global[0],global[1],global[2]);
 181
 182
 183         // setting volume id
 184         AliGeomManager::ELayerID iLayer = AliGeomManager::kTRD1;
 185         switch (fGeom->GetPlane(idet)) {
 186         case 0:
 187                 iLayer = AliGeomManager::kTRD1;
 188                 break;
 189         case 1:
 190                 iLayer = AliGeomManager::kTRD2;
 191                 break;
 192         case 2:
 193                 iLayer = AliGeomManager::kTRD3;
 194                 break;
 195         case 3:
 196                 iLayer = AliGeomManager::kTRD4;
 197                 break;
 198         case 4:
 199                 iLayer = AliGeomManager::kTRD5;
 200                 break;
 201         case 5:
 202                 iLayer = AliGeomManager::kTRD6;
 203                 break;
 204         };
 205         Int_t    modId = fGeom->GetSector(idet) * fGeom->Ncham() + fGeom->GetChamber(idet);
 206         UShort_t volid = AliGeomManager::LayerToVolUID(iLayer, modId);
 207         p.SetVolumeID(volid);
 208
 209         return kTRUE;
 210 }
 211
 212 //____________________________________________________________________
 213 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitter()
 214 {
 215         if(!fgTiltedRieman) fgTiltedRieman = new TLinearFitter(4, "hyp4");
 216         return fgTiltedRieman;
 217 }
 218
 219 //____________________________________________________________________
 220 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitterConstraint()
 221 {
 222         if(!fgTiltedRiemanConstrained) fgTiltedRiemanConstrained = new TLinearFitter(2, "hyp2");
 223         return fgTiltedRiemanConstrained;
 224 }
 225
 226 //____________________________________________________________________
 227 AliRieman* AliTRDtrackerV1::GetRiemanFitter()
 228 {
 229         if(!fgRieman) fgRieman = new AliRieman(AliTRDtrackingChamber::kNTimeBins * AliTRDgeometry::kNplan);
 230         return fgRieman;
 231 }
 232
 233 //_____________________________________________________________________________
 234 Int_t AliTRDtrackerV1::PropagateBack(AliESDEvent *event)
 235 {
 236   //
 237   // Gets seeds from ESD event. The seeds are AliTPCtrack's found and
 238   // backpropagated by the TPC tracker. Each seed is first propagated
 239   // to the TRD, and then its prolongation is searched in the TRD.
 240   // If sufficiently long continuation of the track is found in the TRD
 241   // the track is updated, otherwise it's stored as originaly defined
 242   // by the TPC tracker.
 243   //
 244
 245         Int_t   found    = 0;     // number of tracks found
 246         Float_t foundMin = 20.0;
 247
 248         Int_t    nSeed   = event->GetNumberOfTracks();
 249         if(!nSeed){
 250                 // run stand alone tracking
 251                 if (AliTRDReconstructor::SeedingOn()) Clusters2Tracks(event);
 252                 return 0;
 253         }
 254
 255         Float_t *quality = new Float_t[nSeed];
 256         Int_t   *index   = new Int_t[nSeed];
 257         for (Int_t iSeed = 0; iSeed < nSeed; iSeed++) {
 258                 AliESDtrack *seed = event->GetTrack(iSeed);
 259                 Double_t covariance[15];
 260                 seed->GetExternalCovariance(covariance);
 261                 quality[iSeed] = covariance[0] + covariance[2];
 262         }
 263         // Sort tracks according to covariance of local Y and Z
 264         TMath::Sort(nSeed,quality,index,kFALSE);
 265
 266         // Backpropagate all seeds
 267         for (Int_t iSeed = 0; iSeed < nSeed; iSeed++) {
 268
 269                 // Get the seeds in sorted sequence
 270                 AliESDtrack *seed = event->GetTrack(index[iSeed]);
 271
 272                 // Check the seed status
 273                 ULong_t status = seed->GetStatus();
 274                 if ((status & AliESDtrack::kTPCout) == 0) continue;
 275                 if ((status & AliESDtrack::kTRDout) != 0) continue;
 276
 277                 // Do the back prolongation
 278                 Int_t   lbl         = seed->GetLabel();
 279                 AliTRDtrackV1 *track  = new AliTRDtrackV1(*seed);
 280                 //track->Print();
 281                 track->SetSeedLabel(lbl);
 282                 seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup); // Make backup
 283                 Float_t p4          = track->GetC();
 284                 Int_t   expectedClr = FollowBackProlongation(*track);
 285                 //AliInfo(Form("\nTRACK %d Clusters %d [%d] in chi2 %f", index[iSeed], expectedClr, track->GetNumberOfClusters(), track->GetChi2()));
 286                 //track->Print();
 287
 288                 //Double_t cov[15];
 289                 //seed->GetExternalCovariance(cov);
 290                 //AliInfo(Form("track %d cov[%f %f] 0", index[iSeed], cov[0], cov[2]));
 291
 292                 if ((TMath::Abs(track->GetC() - p4) / TMath::Abs(p4) < 0.2) ||
 293                                 (track->Pt() > 0.8)) {
 294                         //
 295                         // Make backup for back propagation
 296                         //
 297                         Int_t foundClr = track->GetNumberOfClusters();
 298                         if (foundClr >= foundMin) {
 299                                 //AliInfo(Form("Making backup track ncls [%d]...", foundClr));
 300                                 track->CookdEdx();
 301                                 track->CookdEdxTimBin(seed->GetID()); // A.Bercuci 25.07.07
 302                                 track->CookLabel(1. - fgkLabelFraction);
 303                                 if (track->GetBackupTrack()) UseClusters(track->GetBackupTrack());
 304
 305
 306                 //seed->GetExternalCovariance(cov);
 307                 //AliInfo(Form("track %d cov[%f %f] 0 test", index[iSeed], cov[0], cov[2]));
 308
 309                                 // Sign only gold tracks
 310                                 if (track->GetChi2() / track->GetNumberOfClusters() < 4) {
 311                                         if ((seed->GetKinkIndex(0)      ==   0) &&
 312                                                         (track->Pt()                <  1.5)) UseClusters(track);
 313                                 }
 314                                 Bool_t isGold = kFALSE;
 315
 316                                 // Full gold track
 317                                 if (track->GetChi2() / track->GetNumberOfClusters() < 5) {
 318                                         if (track->GetBackupTrack()) seed->UpdateTrackParams(track->GetBackupTrack(),AliESDtrack::kTRDbackup);
 319
 320                                         isGold = kTRUE;
 321                                 }
 322                 //seed->GetExternalCovariance(cov);
 323                 //AliInfo(Form("track %d cov[%f %f] 00", index[iSeed], cov[0], cov[2]));
 324
 325                                 // Almost gold track
 326                                 if ((!isGold)  && (track->GetNCross() == 0) &&
 327                                                 (track->GetChi2() / track->GetNumberOfClusters()  < 7)) {
 328                                         //seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
 329                                         if (track->GetBackupTrack()) seed->UpdateTrackParams(track->GetBackupTrack(),AliESDtrack::kTRDbackup);
 330
 331                                         isGold = kTRUE;
 332                                 }
 333                 //seed->GetExternalCovariance(cov);
 334                 //AliInfo(Form("track %d cov[%f %f] 01", index[iSeed], cov[0], cov[2]));
 335
 336                                 if ((!isGold) && (track->GetBackupTrack())) {
 337                                         if ((track->GetBackupTrack()->GetNumberOfClusters() > foundMin) && ((track->GetBackupTrack()->GetChi2()/(track->GetBackupTrack()->GetNumberOfClusters()+1)) < 7)) {
 338                                                 seed->UpdateTrackParams(track->GetBackupTrack(),AliESDtrack::kTRDbackup);
 339                                                 isGold = kTRUE;
 340                                         }
 341                                 }
 342                 //seed->GetExternalCovariance(cov);
 343                 //AliInfo(Form("track %d cov[%f %f] 02", index[iSeed], cov[0], cov[2]));
 344
 345                                 //if ((track->StatusForTOF() > 0) && (track->GetNCross() == 0) && (Float_t(track->GetNumberOfClusters()) / Float_t(track->GetNExpected())  > 0.4)) {
 346                                         //seed->UpdateTrackParams(track->GetBackupTrack(), AliESDtrack::kTRDbackup);
 347                                 //}
 348                         }
 349                 }
 350                 /**/
 351
 352                 /**/
 353                 // Debug part of tracking
 354 /*              TTreeSRedirector &cstream = *fgDebugStreamer;
 355                 Int_t eventNrInFile = event->GetEventNumberInFile(); // This is most likely NOT the event number you'd like to use. It has nothing to do with the 'real' event number.
 356                 if (AliTRDReconstructor::StreamLevel() > 0) {
 357                         if (track->GetBackupTrack()) {
 358                                 cstream << "Tracks"
 359                                 << "EventNrInFile="  << eventNrInFile
 360                                 << "ESD.="     << seed
 361                                 << "trd.="     << track
 362                                 << "trdback.=" << track->GetBackupTrack()
 363                                 << "\n";
 364                         }
 365                         else {
 366                                 cstream << "Tracks"
 367                                 << "EventNrInFile="  << eventNrInFile
 368                                 << "ESD.="     << seed
 369                                 << "trd.="     << track
 370                                 << "trdback.=" << track
 371                                 << "\n";
 372                         }
 373                 }*/
 374                 /**/
 375
 376                 //seed->GetExternalCovariance(cov);
 377                 //AliInfo(Form("track %d cov[%f %f] 1", index[iSeed], cov[0], cov[2]));
 378
 379                 // Propagation to the TOF (I.Belikov)
 380                 if (track->GetStop() == kFALSE) {
 381                         //AliInfo("Track not stopped in TRD ...");
 382                         Double_t xtof  = 371.0;
 383                         Double_t xTOF0 = 370.0;
 384
 385                         Double_t c2    = track->GetSnp() + track->GetC() * (xtof - track->GetX());
 386                         if (TMath::Abs(c2) >= 0.99) {
 387                                 delete track;
 388                                 continue;
 389                         }
 390
 391                         PropagateToX(*track,xTOF0,fgkMaxStep);
 392
 393                         // Energy losses taken to the account - check one more time
 394                         c2 = track->GetSnp() + track->GetC() * (xtof - track->GetX());
 395                         if (TMath::Abs(c2) >= 0.99) {
 396                                 delete track;
 397                                 continue;
 398                         }
 399
 400                         //if (!PropagateToX(*track,xTOF0,fgkMaxStep)) {
 401                         //      fHBackfit->Fill(7);
 402                         //delete track;
 403                         //      continue;
 404                         //}
 405
 406                         Double_t ymax = xtof * TMath::Tan(0.5 * AliTRDgeometry::GetAlpha());
 407                         Double_t y;
 408                         track->GetYAt(xtof,GetBz(),y);
 409                         if (y >  ymax) {
 410                                 if (!track->Rotate( AliTRDgeometry::GetAlpha())) {
 411                                         delete track;
 412                                         continue;
 413                                 }
 414                         }else if (y < -ymax) {
 415                                 if (!track->Rotate(-AliTRDgeometry::GetAlpha())) {
 416                                         delete track;
 417                                         continue;
 418                                 }
 419                         }
 420
 421                         if (track->PropagateTo(xtof)) {
 422                                 //AliInfo("set kTRDout");
 423                                 seed->UpdateTrackParams(track,AliESDtrack::kTRDout);
 424
 425                                 for (Int_t i = 0; i < AliESDtrack::kNPlane; i++) {
 426                                         for (Int_t j = 0; j < AliESDtrack::kNSlice; j++) {
 427                                                 seed->SetTRDsignals(track->GetPIDsignals(i,j),i,j);
 428                                         }
 429                                         seed->SetTRDTimBin(track->GetPIDTimBin(i),i);
 430                                 }
 431                                 //seed->SetTRDtrack(new AliTRDtrack(*track));
 432                                 if (track->GetNumberOfClusters() > foundMin) found++;
 433                         }
 434                 } else {
 435                         //AliInfo("Track stopped in TRD ...");
 436
 437                         if ((track->GetNumberOfClusters() >              15) &&
 438                                         (track->GetNumberOfClusters() > 0.5*expectedClr)) {
 439                                 seed->UpdateTrackParams(track,AliESDtrack::kTRDout);
 440
 441                                 //seed->SetStatus(AliESDtrack::kTRDStop);
 442                                 for (Int_t i = 0; i < AliESDtrack::kNPlane; i++) {
 443                                         for (Int_t j = 0; j <AliESDtrack::kNSlice; j++) {
 444                                                 seed->SetTRDsignals(track->GetPIDsignals(i,j),i,j);
 445                                         }
 446                                         seed->SetTRDTimBin(track->GetPIDTimBin(i),i);
 447                                 }
 448                                 //seed->SetTRDtrack(new AliTRDtrack(*track));
 449                                 found++;
 450                         }
 451                 }
 452
 453                 //if (((t->GetStatus()&AliESDtrack::kTRDout)!=0 )
 454
 455                 seed->SetTRDQuality(track->StatusForTOF());
 456                 seed->SetTRDBudget(track->GetBudget(0));
 457                 delete track;
 458         }
 459
 460
 461         AliInfo(Form("Number of seeds: %d", nSeed));
 462         AliInfo(Form("Number of back propagated TRD tracks: %d", found));
 463
 464         delete [] index;
 465         delete [] quality;
 466
 467   return 0;
 468 }
 469
 470
 471 //____________________________________________________________________
 472 Int_t AliTRDtrackerV1::RefitInward(AliESDEvent *event)
 473 {
 474   //
 475   // Refits tracks within the TRD. The ESD event is expected to contain seeds
 476   // at the outer part of the TRD.
 477   // The tracks are propagated to the innermost time bin
 478   // of the TRD and the ESD event is updated
 479   // Origin: Thomas KUHR (Thomas.Kuhr@cern.ch)
 480   //
 481
 482   Int_t   nseed    = 0; // contor for loaded seeds
 483   Int_t   found    = 0; // contor for updated TRD tracks
 484
 485   // Calibration monitor
 486   AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance();
 487   if (!calibra) AliInfo("Could not get Calibra instance\n");
 488
 489
 490   AliTRDtrackV1 track;
 491   for (Int_t itrack = 0; itrack < event->GetNumberOfTracks(); itrack++) {
 492     AliESDtrack *seed = event->GetTrack(itrack);
 493                 new(&track) AliTRDtrackV1(*seed);
 494
 495     if (track.GetX() < 270.0) {
 496       seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
 497       //AliInfo(Form("Remove for X = %7.3f [270.]\n", track.GetX()));
 498                         continue;
 499     }
 500
 501     ULong_t status = seed->GetStatus();
 502     if((status & AliESDtrack::kTRDout) == 0) continue;
 503     if((status & AliESDtrack::kTRDin)  != 0) continue;
 504     nseed++;
 505
 506     track.ResetCovariance(50.0);
 507
 508                 // do the propagation and processing
 509     Bool_t kUPDATE = kFALSE;
 510                 Double_t xTPC = 250.0;
 511     if(FollowProlongation(track)){
 512                         // computes PID for track
 513                         track.CookPID();
 514                         // update calibration references using this track
 515                         if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(&track);
 516
 517                         // Prolongate to TPC
 518                         if (PropagateToX(track, xTPC, fgkMaxStep)) { //  -with update
 519                                 seed->UpdateTrackParams(&track, AliESDtrack::kTRDrefit);
 520                                 track.UpdateESDtrack(seed);
 521                                 // Add TRD track to ESDfriendTrack
 522                                 if (AliTRDReconstructor::StreamLevel() > 0 /*&& quality TODO*/){
 523                                         AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(track);
 524                                         calibTrack->SetOwner();
 525                                         seed->AddCalibObject(calibTrack);
 526                                 }
 527                                 found++;
 528                                 kUPDATE = kTRUE;
 529                         }
 530                 }
 531
 532                 // Prolongate to TPC without update
 533                 if(!kUPDATE) {
 534       AliTRDtrackV1 tt(*seed);
 535       if (PropagateToX(tt, xTPC, fgkMaxStep)) seed->UpdateTrackParams(&tt, AliESDtrack::kTRDrefit);
 536     }
 537   }
 538   AliInfo(Form("Number of loaded seeds: %d",nseed));
 539   AliInfo(Form("Number of found tracks from loaded seeds: %d",found));
 540
 541         return 0;
 542 }
 543
 544
 545 //____________________________________________________________________
 546 Int_t AliTRDtrackerV1::FollowProlongation(AliTRDtrackV1 &t)
 547 {
 548 // Extrapolates the TRD track in the TPC direction.
 549 //
 550 // Parameters
 551 //   t : the TRD track which has to be extrapolated
 552 //
 553 // Output
 554 //   number of clusters attached to the track
 555 //
 556 // Detailed description
 557 //
 558 // Starting from current radial position of track <t> this function
 559 // extrapolates the track through the 6 TRD layers. The following steps
 560 // are being performed for each plane:
 561 // 1. prepare track:
 562 //   a. get plane limits in the local x direction
 563 //   b. check crossing sectors
 564 //   c. check track inclination
 565 // 2. search tracklet in the tracker list (see GetTracklet() for details)
 566 // 3. evaluate material budget using the geo manager
 567 // 4. propagate and update track using the tracklet information.
 568 //
 569 // Debug level 2
 570 //
 571
 572         //AliInfo("");
 573         Int_t    nClustersExpected = 0;
 574         Int_t lastplane = 5; //GetLastPlane(&t);
 575         for (Int_t iplane = lastplane; iplane >= 0; iplane--) {
 576     Int_t   index   = 0;
 577     AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
 578                 if(!tracklet) continue;
 579                 if(!tracklet->IsOK()) AliWarning("tracklet not OK");
 580
 581                 t.SetTracklet(tracklet, iplane, index);
 582
 583                 Double_t x  = tracklet->GetX0();
 584     if (x < (t.GetX()-fgkMaxStep) && !PropagateToX(t, x+fgkMaxStep, fgkMaxStep)) break;
 585     if (!AdjustSector(&t)) break;
 586
 587     // Start global position
 588     Double_t xyz0[3];
 589     t.GetXYZ(xyz0);
 590
 591                 // End global position
 592     Double_t alpha = t.GetAlpha(), y, z;
 593     if (!t.GetProlongation(x,y,z)) break;
 594     Double_t xyz1[3];
 595     xyz1[0] =  x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
 596     xyz1[1] =  x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
 597     xyz1[2] =  z;
 598
 599     // Get material budget
 600     Double_t param[7];
 601     AliTracker::MeanMaterialBudget(xyz0, xyz1, param);
 602     Double_t xrho= param[0]*param[4];
 603     Double_t xx0 = param[1]; // Get mean propagation parameters
 604
 605     // Propagate and update
 606                 t.PropagateTo(x, xx0, xrho);
 607           if (!AdjustSector(&t)) break;
 608
 609     Double_t maxChi2 = t.GetPredictedChi2(tracklet);
 610           if (maxChi2 < 1e+10 && t.Update(tracklet, maxChi2)){
 611                 nClustersExpected += tracklet->GetN();
 612         }
 613   }
 614
 615         if(AliTRDReconstructor::StreamLevel() > 1){
 616                 Int_t index;
 617                 for(int iplane=0; iplane<6; iplane++){
 618                         AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
 619                         if(!tracklet) continue;
 620                         t.SetTracklet(tracklet, iplane, index);
 621                 }
 622
 623                 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
 624                 TTreeSRedirector &cstreamer = *fgDebugStreamer;
 625                 cstreamer << "FollowProlongation"
 626                         << "EventNumber="       << eventNumber
 627                         << "ncl="                                       << nClustersExpected
 628                         << "track.="                    << &t
 629                         << "\n";
 630         }
 631
 632   return nClustersExpected;
 633
 634 }
 635
 636 //_____________________________________________________________________________
 637 Int_t AliTRDtrackerV1::FollowBackProlongation(AliTRDtrackV1 &t)
 638 {
 639 // Extrapolates the TRD track in the TOF direction.
 640 //
 641 // Parameters
 642 //   t : the TRD track which has to be extrapolated
 643 //
 644 // Output
 645 //   number of clusters attached to the track
 646 //
 647 // Detailed description
 648 //
 649 // Starting from current radial position of track <t> this function
 650 // extrapolates the track through the 6 TRD layers. The following steps
 651 // are being performed for each plane:
 652 // 1. prepare track:
 653 //   a. get plane limits in the local x direction
 654 //   b. check crossing sectors
 655 //   c. check track inclination
 656 // 2. build tracklet (see AliTRDseed::AttachClusters() for details)
 657 // 3. evaluate material budget using the geo manager
 658 // 4. propagate and update track using the tracklet information.
 659 //
 660 // Debug level 2
 661 //
 662
 663         Int_t nClustersExpected = 0;
 664   Double_t clength = AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick();
 665   AliTRDtrackingChamber *chamber = 0x0;
 666
 667   // Loop through the TRD planes
 668   for (Int_t iplane = 0; iplane < AliTRDgeometry::Nplan(); iplane++) {
 669                 // BUILD TRACKLET IF NOT ALREADY BUILT
 670                 Double_t x = 0., y, z, alpha;
 671     AliTRDseedV1 tracklet(*t.GetTracklet(iplane));
 672                 if(!tracklet.IsOK()){
 673                 alpha = t.GetAlpha();
 674                 Int_t sector = Int_t(alpha/AliTRDgeometry::GetAlpha() + (alpha>0. ? 0 : AliTRDgeometry::kNsect));
 675
 676                 if(!fTrSec[sector].GetNChambers()) continue;
 677
 678                 if((x = fTrSec[sector].GetX(iplane)) < 1.) continue;
 679
 680                         if (!t.GetProlongation(x, y, z)) break;
 681                         Int_t stack = fGeom->GetChamber(z, iplane);
 682                         Int_t nCandidates = stack >= 0 ? 1 : 2;
 683                         z -= stack >= 0 ? 0. : 4.;
 684
 685                         for(int icham=0; icham<nCandidates; icham++, z+=8){
 686                                 if((stack = fGeom->GetChamber(z, iplane)) < 0) continue;
 687
 688                                 if(!(chamber = fTrSec[sector].GetChamber(stack, iplane))) continue;
 689
 690                                 if(chamber->GetNClusters() < fgNTimeBins*AliTRDReconstructor::RecoParam()->GetFindableClusters()) continue;
 691
 692                                 x = chamber->GetX();
 693
 694                                 AliTRDpadPlane *pp = fGeom->GetPadPlane(iplane, stack);
 695                                 tracklet.SetTilt(TMath::Tan(-TMath::DegToRad()*pp->GetTiltingAngle()));
 696                                 tracklet.SetPadLength(pp->GetLengthIPad());
 697                                 tracklet.SetPlane(iplane);
 698                                 tracklet.SetX0(x);
 699                                 tracklet.Init(&t);
 700                                 if(!tracklet.AttachClustersIter(chamber, 1000.)) continue;
 701                                 tracklet.Init(&t);
 702
 703                 if(tracklet.GetN() < fgNTimeBins * AliTRDReconstructor::RecoParam()->GetFindableClusters()) continue;
 704
 705                                 break;
 706                         }
 707                 }
 708     if(!tracklet.IsOK()){
 709                         if(x < 1.) continue; //temporary
 710                         if(!PropagateToX(t, x-fgkMaxStep, fgkMaxStep)) break;
 711                         if(!AdjustSector(&t)) break;
 712                         if(TMath::Abs(t.GetSnp()) > fgkMaxSnp) break;
 713         continue;
 714     }
 715
 716                 // Propagate closer to the current chamber if neccessary
 717     x -= clength;
 718     if (x > (fgkMaxStep + t.GetX()) && !PropagateToX(t, x-fgkMaxStep, fgkMaxStep)) break;
 719     if (!AdjustSector(&t)) break;
 720     if (TMath::Abs(t.GetSnp()) > fgkMaxSnp) break;
 721
 722                 // load tracklet to the tracker and the track
 723                 Int_t index = SetTracklet(&tracklet);
 724                 t.SetTracklet(&tracklet, iplane, index);
 725
 726
 727                 // Calculate the mean material budget along the path inside the chamber
 728     //Calculate global entry and exit positions of the track in chamber (only track prolongation)
 729     Double_t xyz0[3]; // entry point
 730                 t.GetXYZ(xyz0);
 731                 alpha = t.GetAlpha();
 732                 x = tracklet.GetX0();
 733                 if (!t.GetProlongation(x, y, z)) break;
 734                 Double_t xyz1[3]; // exit point
 735                 xyz1[0] =  x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
 736     xyz1[1] = +x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
 737     xyz1[2] =  z;
 738     Double_t param[7];
 739                 AliTracker::MeanMaterialBudget(xyz0, xyz1, param);
 740     // The mean propagation parameters
 741     Double_t xrho = param[0]*param[4]; // density*length
 742     Double_t xx0  = param[1]; // radiation length
 743
 744                 // Propagate and update track
 745                 t.PropagateTo(x, xx0, xrho);
 746           if (!AdjustSector(&t)) break;
 747                 Double_t maxChi2 = t.GetPredictedChi2(&tracklet);
 748                 if (maxChi2<1e+10 && t.Update(&tracklet, maxChi2)){
 749                         nClustersExpected += tracklet.GetN();
 750                 }
 751                 // Reset material budget if 2 consecutive gold
 752                 if(iplane>0 && tracklet.GetN() + t.GetTracklet(iplane-1)->GetN() > 20) t.SetBudget(2, 0.);
 753
 754                 // Make backup of the track until is gold
 755                 // TO DO update quality check of the track.
 756                 // consider comparison with fTimeBinsRange
 757                 Float_t ratio0 = tracklet.GetN() / Float_t(fgNTimeBins);
 758                 //Float_t ratio1 = Float_t(t.GetNumberOfClusters()+1) / Float_t(t.GetNExpected()+1);
 759     //printf("tracklet.GetChi2() %f     [< 18.0]\n", tracklet.GetChi2());
 760                 //printf("ratio0    %f              [>   0.8]\n", ratio0);
 761                 //printf("ratio1     %f             [>   0.6]\n", ratio1);
 762                 //printf("ratio0+ratio1 %f          [>   1.5]\n", ratio0+ratio1);
 763                 //printf("t.GetNCross()  %d         [==    0]\n", t.GetNCross());
 764                 //printf("TMath::Abs(t.GetSnp()) %f [<  0.85]\n", TMath::Abs(t.GetSnp()));
 765                 //printf("t.GetNumberOfClusters() %d [>    20]\n", t.GetNumberOfClusters());
 766
 767                 if (//(tracklet.GetChi2()      <  18.0) && TO DO check with FindClusters and move it to AliTRDseed::Update
 768         (ratio0                  >   0.8) &&
 769         //(ratio1                  >   0.6) &&
 770         //(ratio0+ratio1           >   1.5) &&
 771         (t.GetNCross()           ==    0) &&
 772         (TMath::Abs(t.GetSnp())  <  0.85) &&
 773         (t.GetNumberOfClusters() >    20)) t.MakeBackupTrack();
 774
 775         } // end planes loop
 776
 777         if(AliTRDReconstructor::StreamLevel() > 1){
 778                 TTreeSRedirector &cstreamer = *fgDebugStreamer;
 779                 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
 780                 cstreamer << "FollowBackProlongation"
 781                         << "EventNumber="                       << eventNumber
 782                         << "ncl="                                                       << nClustersExpected
 783                         << "track.="                                    << &t
 784                         << "\n";
 785         }
 786
 787         return nClustersExpected;
 788 }
 789
 790 //_____________________________________________________________________________
 791 void AliTRDtrackerV1::FitLeastSquare(Int_t nPoints, Float_t *x, Float_t *y, Float_t *error, Float_t *fitparams){
 792 //
 793 // Performing a least square fit
 794 //
 795 // Parameters:  - Number of Points
 796 //                              - x-data (array)
 797 //                              - y-data (array)
 798 //                              - error assumption in y-coordinate
 799 //                              - fitparams (array with length 2, as output)
 800 // Output:              -
 801 //
 802 // The first entry in fitparams is the offset, the second entry the slope
 803 //
 804 // @TODO: Implement error paramterisation
 805 //
 806         Float_t sumweights = 0,
 807                         sumx = 0,
 808                         sumy = 0,
 809                         sumxy = 0,
 810                         sumx2 = 0;
 811         for(Int_t ipt = 0; ipt < nPoints; ipt++){
 812                 sumweights += error[ipt];
 813                 sumx += x[ipt] * error[ipt];
 814                 sumy += y[ipt] * error[ipt];
 815                 sumxy += x[ipt] * y[ipt] * error[ipt];
 816                 sumx2 += x[ipt] * x[ipt] * error[ipt];
 817         }
 818         Float_t denominator = sumweights * sumx2 - sumx * sumx;
 819         fitparams[0] = (sumy * sumx2 - sumx * sumxy) / denominator;
 820         fitparams[1] = (sumweights * sumxy - sumx * sumy)/ denominator;
 821 }
 822
 823 //_________________________________________________________________________
 824 Float_t AliTRDtrackerV1::FitRieman(AliTRDseedV1 *tracklets, Double_t *chi2, Int_t *planes){
 825 //
 826 // Fits a Riemann-circle to the given points without tilting pad correction.
 827 // The fit is performed using an instance of the class AliRieman (equations
 828 // and transformations see documentation of this class)
 829 // Afterwards all the tracklets are Updated
 830 //
 831 // Parameters: - Array of tracklets (AliTRDseedV1)
 832 //             - Storage for the chi2 values (beginning with direction z)
 833 //             - Seeding configuration
 834 // Output:     - The curvature
 835 //
 836   AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
 837         fitter->Reset();
 838   Int_t allplanes[] = {0, 1, 2, 3, 4, 5};
 839   Int_t *ppl = &allplanes[0];
 840         Int_t maxLayers = 6;
 841   if(planes){
 842     maxLayers = 4;
 843     ppl = planes;
 844   }
 845   for(Int_t il = 0; il < maxLayers; il++){
 846                 if(!tracklets[ppl[il]].IsOK()) continue;
 847     fitter->AddPoint(tracklets[ppl[il]].GetX0(), tracklets[ppl[il]].GetYfitR(0), tracklets[ppl[il]].GetZProb(),1,10);
 848   }
 849   fitter->Update();
 850   // Set the reference position of the fit and calculate the chi2 values
 851   memset(chi2, 0, sizeof(Double_t) * 2);
 852         for(Int_t il = 0; il < maxLayers; il++){
 853                 // Reference positions
 854                 tracklets[ppl[il]].Init(fitter);
 855
 856                 // chi2
 857                 if((!tracklets[ppl[il]].IsOK()) && (!planes)) continue;
 858                 chi2[0] += tracklets[ppl[il]].GetChi2Y();
 859                 chi2[1] += tracklets[ppl[il]].GetChi2Z();
 860         }
 861         return fitter->GetC();
 862 }
 863
 864 //_________________________________________________________________________
 865 void AliTRDtrackerV1::FitRieman(AliTRDcluster **seedcl, Double_t chi2[2])
 866 {
 867 //
 868 // Performs a Riemann helix fit using the seedclusters as spacepoints
 869 // Afterwards the chi2 values are calculated and the seeds are updated
 870 //
 871 // Parameters: - The four seedclusters
 872 //             - The tracklet array (AliTRDseedV1)
 873 //             - The seeding configuration
 874 //             - Chi2 array
 875 //
 876 // debug level 2
 877 //
 878         AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
 879         fitter->Reset();
 880         for(Int_t i = 0; i < 4; i++)
 881                 fitter->AddPoint(seedcl[i]->GetX(), seedcl[i]->GetY(), seedcl[i]->GetZ(), 1, 10);
 882         fitter->Update();
 883
 884
 885         // Update the seed and calculated the chi2 value
 886         chi2[0] = 0; chi2[1] = 0;
 887         for(Int_t ipl = 0; ipl < kNSeedPlanes; ipl++){
 888                 // chi2
 889                 chi2[0] += (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX()));
 890                 chi2[1] += (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX()));
 891         }
 892 }
 893
 894
 895 //_________________________________________________________________________
 896 Float_t AliTRDtrackerV1::FitTiltedRiemanConstraint(AliTRDseedV1 *tracklets, Double_t zVertex)
 897 {
 898 //
 899 // Fits a helix to the clusters. Pad tilting is considered. As constraint it is
 900 // assumed that the vertex position is set to 0.
 901 // This method is very usefull for high-pt particles
 902 // Basis for the fit: (x - x0)^2 + (y - y0)^2 - R^2 = 0
 903 //      x0, y0: Center of the circle
 904 // Measured y-position: ymeas = y - tan(phiT)(zc - zt)
 905 //      zc: center of the pad row
 906 // Equation which has to be fitted (after transformation):
 907 // a + b * u + e * v + 2*(ymeas + tan(phiT)(z - zVertex))*t = 0
 908 // Transformation:
 909 // t = 1/(x^2 + y^2)
 910 // u = 2 * x * t
 911 // v = 2 * x * tan(phiT) * t
 912 // Parameters in the equation:
 913 //    a = -1/y0, b = x0/y0, e = dz/dx
 914 //
 915 // The Curvature is calculated by the following equation:
 916 //               - curv = a/Sqrt(b^2 + 1) = 1/R
 917 // Parameters:   - the 6 tracklets
 918 //               - the Vertex constraint
 919 // Output:       - the Chi2 value of the track
 920 //
 921 // debug level 5
 922 //
 923
 924         TLinearFitter *fitter = GetTiltedRiemanFitterConstraint();
 925         fitter->StoreData(kTRUE);
 926         fitter->ClearPoints();
 927
 928         Float_t x, y, z, w, t, error, tilt;
 929         Double_t uvt[2];
 930         Int_t nPoints = 0;
 931         for(Int_t ipl = 0; ipl < AliTRDgeometry::kNplan; ipl++){
 932                 if(!tracklets[ipl].IsOK()) continue;
 933                 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
 934                         if(!tracklets[ipl].IsUsable(itb)) continue;
 935                         x = tracklets[ipl].GetX(itb) + tracklets[ipl].GetX0();
 936                         y = tracklets[ipl].GetY(itb);
 937                         z = tracklets[ipl].GetZ(itb);
 938                         tilt = tracklets[ipl].GetTilt();
 939                         // Transformation
 940                         t = 1/(x * x + y * y);
 941                         uvt[0] = 2 * x* t;
 942                         uvt[1] =  2.0 * tilt * x * t;
 943                         w = 2.0 * (y + tilt * (z - zVertex)) * t;
 944                         error = 2 * 0.2 * t;
 945                         fitter->AddPoint(uvt, w, error);
 946                         nPoints++;
 947                 }
 948         }
 949         fitter->Eval();
 950
 951         // Calculate curvature
 952         Double_t a = fitter->GetParameter(0);
 953         Double_t b = fitter->GetParameter(1);
 954         Double_t curvature = a/TMath::Sqrt(b*b + 1);
 955
 956         Float_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
 957         for(Int_t ip = 0; ip < AliTRDtrackerV1::kNPlanes; ip++)
 958                 tracklets[ip].SetCC(curvature);
 959
 960         if(AliTRDReconstructor::StreamLevel() >= 5){
 961                 //Linear Model on z-direction
 962                 Double_t xref = CalculateReferenceX(tracklets);         // Relative to the middle of the stack
 963                 Double_t slope = fitter->GetParameter(2);
 964                 Double_t zref = slope * xref;
 965                 Float_t chi2Z = CalculateChi2Z(tracklets, zref, slope, xref);
 966                 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
 967                 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
 968                 TTreeSRedirector &treeStreamer = *fgDebugStreamer;
 969                 treeStreamer << "FitTiltedRiemanConstraint"
 970                         << "EventNumber="               << eventNumber
 971                         << "CandidateNumber="   << candidateNumber
 972                         << "Curvature="                         << curvature
 973                         << "Chi2Track="                         << chi2track
 974                         << "Chi2Z="                                             << chi2Z
 975                         << "zref="                                              << zref
 976                         << "\n";
 977         }
 978         return chi2track;
 979 }
 980
 981 //_________________________________________________________________________
 982 Float_t AliTRDtrackerV1::FitTiltedRieman(AliTRDseedV1 *tracklets, Bool_t sigError)
 983 {
 984 //
 985 // Performs a Riemann fit taking tilting pad correction into account
 986 // The equation of a Riemann circle, where the y position is substituted by the
 987 // measured y-position taking pad tilting into account, has to be transformed
 988 // into a 4-dimensional hyperplane equation
 989 // Riemann circle: (x-x0)^2 + (y-y0)^2 -R^2 = 0
 990 // Measured y-Position: ymeas = y - tan(phiT)(zc - zt)
 991 //          zc: center of the pad row
 992 //          zt: z-position of the track
 993 // The z-position of the track is assumed to be linear dependent on the x-position
 994 // Transformed equation: a + b * u + c * t + d * v  + e * w - 2 * (ymeas + tan(phiT) * zc) * t = 0
 995 // Transformation:       u = 2 * x * t
 996 //                       v = 2 * tan(phiT) * t
 997 //                       w = 2 * tan(phiT) * (x - xref) * t
 998 //                       t = 1 / (x^2 + ymeas^2)
 999 // Parameters:           a = -1/y0
1000 //                       b = x0/y0
1001 //                       c = (R^2 -x0^2 - y0^2)/y0
1002 //                       d = offset
1003 //                       e = dz/dx
1004 // If the offset respectively the slope in z-position is impossible, the parameters are fixed using
1005 // results from the simple riemann fit. Afterwards the fit is redone.
1006 // The curvature is calculated according to the formula:
1007 //                       curv = a/(1 + b^2 + c*a) = 1/R
1008 //
1009 // Paramters:   - Array of tracklets (connected to the track candidate)
1010 //              - Flag selecting the error definition
1011 // Output:      - Chi2 values of the track (in Parameter list)
1012 //
1013         TLinearFitter *fitter = GetTiltedRiemanFitter();
1014         fitter->StoreData(kTRUE);
1015         fitter->ClearPoints();
1016
1017         Double_t xref = CalculateReferenceX(tracklets);
1018         Double_t x, y, z, t, tilt, xdelta, rhs, error;
1019         Double_t uvt[4];
1020         Int_t nPoints = 0;
1021         // Containers for Least-square fitter
1022         Float_t x0[kNPlanes], zfit[kNPlanes], errors[kNPlanes];
1023         Int_t nLayers = 0;
1024         for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1025                 if(!tracklets[ipl].IsOK()) continue;
1026                 x0[nLayers] = tracklets[ipl].GetX0();
1027                 zfit[nLayers] = tracklets[ipl].GetZfit(0);
1028                 Double_t meanError = 0;
1029                 Int_t ncls = 0;
1030                 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1031                         if (!tracklets[ipl].IsUsable(itb)) continue;
1032                         x = tracklets[ipl].GetX(itb) + tracklets[ipl].GetX0();
1033                         y = tracklets[ipl].GetY(itb);
1034                         z = tracklets[ipl].GetZ(itb);
1035                         tilt = tracklets[ipl].GetTilt();
1036                         xdelta = x - xref;
1037                         // Transformation
1038                         t = 1/(x*x + y*y);
1039                         uvt[0] = 2.0 * x * t;
1040                         uvt[1] = t;
1041                         uvt[2] = 2.0 * tilt * t;
1042                         uvt[3] = 2.0 * tilt * xdelta * t;
1043                         rhs = 2.0 * (y + tilt*z) * t;
1044                         // error definition changes for the different calls
1045                         error = 2.0 * t;
1046                         error *= sigError ? tracklets[ipl].GetSigmaY() : 0.2;
1047                         fitter->AddPoint(uvt, rhs, error);
1048                         nPoints++;
1049                         meanError += tracklets[ipl].GetClusters(itb)->GetSigmaZ2();
1050                         ncls++;
1051                 }
1052                 errors[nLayers] = meanError / ncls;
1053                 nLayers++;
1054         }
1055
1056         fitter->Eval();
1057
1058         Double_t offset = fitter->GetParameter(3);
1059         Double_t slope  = fitter->GetParameter(4);
1060
1061         // Linear fitter  - not possible to make boundaries
1062         // Do not accept non possible z and dzdx combinations
1063         Bool_t acceptablez = kTRUE;
1064         Double_t zref = 0.0;
1065         for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1066                 if(!tracklets[iLayer].IsOK()) continue;
1067                 zref = offset + slope * (tracklets[iLayer].GetX0() - xref);
1068                 if (TMath::Abs(tracklets[iLayer].GetZProb() - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1069                         acceptablez = kFALSE;
1070         }
1071         if (!acceptablez) {
1072                 Float_t fitparams[2];
1073                 FitLeastSquare(nLayers, x0, zfit, errors, fitparams);
1074                 Double_t dzmf   = fitparams[1];
1075                 Double_t zmf    = fitparams[0] + dzmf * xref;
1076                 //printf("In FitTilted Rieman: zmf = %f, meandz = %f\n", zmf, dzmf);
1077                 fgTiltedRieman->FixParameter(3, zmf);
1078                 fgTiltedRieman->FixParameter(4, dzmf);
1079                 fitter->Eval();
1080                 fitter->ReleaseParameter(3);
1081                 fitter->ReleaseParameter(4);
1082                 offset = fitter->GetParameter(3);
1083                 slope = fitter->GetParameter(4);
1084         }
1085
1086         // Calculate Curvarture
1087         Double_t a     =  fitter->GetParameter(0);
1088         Double_t b     =  fitter->GetParameter(1);
1089         Double_t c     =  fitter->GetParameter(2);
1090         Double_t curvature =  1.0 + b*b - c*a;
1091         if (curvature > 0.0)
1092                 curvature  =  a / TMath::Sqrt(curvature);
1093
1094         Double_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1095
1096         // Update the tracklets
1097         Double_t dy, dz;
1098         for(Int_t iLayer = 0; iLayer < AliTRDtrackerV1::kNPlanes; iLayer++) {
1099
1100                 x  = tracklets[iLayer].GetX0();
1101                 y  = 0;
1102                 z  = 0;
1103                 dy = 0;
1104                 dz = 0;
1105
1106                 // y:     R^2 = (x - x0)^2 + (y - y0)^2
1107                 //     =>   y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1108                 //          R = Sqrt() = 1/Curvature
1109                 //     =>   y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
1110                 Double_t res = (x * a + b);                                                             // = (x - x0)/y0
1111                 res *= res;
1112                 res  = 1.0 - c * a + b * b - res;                                       // = (R^2 - (x - x0)^2)/y0^2
1113                 if (res >= 0) {
1114                         res = TMath::Sqrt(res);
1115                         y    = (1.0 - res) / a;
1116                 }
1117
1118                 // dy:      R^2 = (x - x0)^2 + (y - y0)^2
1119                 //     =>     y = +/- Sqrt(R^2 - (x - x0)^2) + y0
1120                 //     => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1121                 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
1122                 //     => dy/dx =  (x - x0)/(1/(cr^2) - (x - x0)^2)
1123                 Double_t x0 = -b / a;
1124                 if (-c * a + b * b + 1 > 0) {
1125                         if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
1126                                 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
1127                                 if (a < 0) yderiv *= -1.0;
1128                                 dy = yderiv;
1129                         }
1130                 }
1131                 z  = offset + slope * (x - xref);
1132                 dz = slope;
1133                 tracklets[iLayer].SetYref(0, y);
1134                 tracklets[iLayer].SetYref(1, dy);
1135                 tracklets[iLayer].SetZref(0, z);
1136                 tracklets[iLayer].SetZref(1, dz);
1137                 tracklets[iLayer].SetC(curvature);
1138                 tracklets[iLayer].SetChi2(chi2track);
1139   }
1140
1141         if(AliTRDReconstructor::StreamLevel() >=5){
1142                 TTreeSRedirector &cstreamer = *fgDebugStreamer;
1143                 Int_t eventNumber                       = AliTRDtrackerDebug::GetEventNumber();
1144                 Int_t candidateNumber   = AliTRDtrackerDebug::GetCandidateNumber();
1145                 Double_t chi2z = CalculateChi2Z(tracklets, offset, slope, xref);
1146                 cstreamer << "FitTiltedRieman0"
1147                 << "EventNumber="                       << eventNumber
1148                 << "CandidateNumber="   << candidateNumber
1149                 << "xref="                                              << xref
1150                 << "Chi2Z="                                             << chi2z
1151                 << "\n";
1152         }
1153         return chi2track;
1154 }
1155
1156 //_________________________________________________________________________
1157 Float_t AliTRDtrackerV1::CalculateChi2Z(AliTRDseedV1 *tracklets, Double_t offset, Double_t slope, Double_t xref)
1158 {
1159 //
1160 // Calculates the chi2-value of the track in z-Direction including tilting pad correction.
1161 // A linear dependence on the x-value serves as a model.
1162 // The parameters are related to the tilted Riemann fit.
1163 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
1164 //             - the offset for the reference x
1165 //             - the slope
1166 //             - the reference x position
1167 // Output:     - The Chi2 value of the track in z-Direction
1168 //
1169         Float_t chi2Z = 0, nLayers = 0;
1170         for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNplan; iLayer++) {
1171                 if(!tracklets[iLayer].IsOK()) continue;
1172                 Double_t z = offset + slope * (tracklets[iLayer].GetX0() - xref);
1173                 chi2Z += TMath::Abs(tracklets[iLayer].GetMeanz() - z);
1174                 nLayers++;
1175         }
1176         chi2Z /= TMath::Max((nLayers - 3.0),1.0);
1177         return chi2Z;
1178 }
1179
1180 //_____________________________________________________________________________
1181 Int_t AliTRDtrackerV1::PropagateToX(AliTRDtrackV1 &t, Double_t xToGo, Double_t maxStep)
1182 {
1183   //
1184   // Starting from current X-position of track <t> this function
1185   // extrapolates the track up to radial position <xToGo>.
1186   // Returns 1 if track reaches the plane, and 0 otherwise
1187   //
1188
1189   const Double_t kEpsilon = 0.00001;
1190
1191   // Current track X-position
1192   Double_t xpos = t.GetX();
1193
1194   // Direction: inward or outward
1195   Double_t dir  = (xpos < xToGo) ? 1.0 : -1.0;
1196
1197   while (((xToGo - xpos) * dir) > kEpsilon) {
1198
1199     Double_t xyz0[3];
1200     Double_t xyz1[3];
1201     Double_t param[7];
1202     Double_t x;
1203     Double_t y;
1204     Double_t z;
1205
1206     // The next step size
1207     Double_t step = dir * TMath::Min(TMath::Abs(xToGo-xpos),maxStep);
1208
1209     // Get the global position of the starting point
1210     t.GetXYZ(xyz0);
1211
1212     // X-position after next step
1213     x = xpos + step;
1214
1215     // Get local Y and Z at the X-position of the next step
1216     if (!t.GetProlongation(x,y,z)) {
1217       return 0; // No prolongation possible
1218     }
1219
1220     // The global position of the end point of this prolongation step
1221     xyz1[0] =  x * TMath::Cos(t.GetAlpha()) - y * TMath::Sin(t.GetAlpha());
1222     xyz1[1] = +x * TMath::Sin(t.GetAlpha()) + y * TMath::Cos(t.GetAlpha());
1223     xyz1[2] =  z;
1224
1225     // Calculate the mean material budget between start and
1226     // end point of this prolongation step
1227     AliTracker::MeanMaterialBudget(xyz0, xyz1, param);
1228
1229     // Propagate the track to the X-position after the next step
1230     if (!t.PropagateTo(x,param[1],param[0]*param[4])) {
1231       return 0;
1232     }
1233
1234     // Rotate the track if necessary
1235     AdjustSector(&t);
1236
1237     // New track X-position
1238     xpos = t.GetX();
1239
1240   }
1241
1242   return 1;
1243
1244 }
1245
1246
1247 //_____________________________________________________________________________
1248 Int_t AliTRDtrackerV1::ReadClusters(TClonesArray* &array, TTree *clusterTree) const
1249 {
1250   //
1251   // Reads AliTRDclusters from the file.
1252   // The names of the cluster tree and branches
1253   // should match the ones used in AliTRDclusterizer::WriteClusters()
1254   //
1255
1256   Int_t nsize = Int_t(clusterTree->GetTotBytes() / (sizeof(AliTRDcluster)));
1257   TObjArray *clusterArray = new TObjArray(nsize+1000);
1258
1259   TBranch *branch = clusterTree->GetBranch("TRDcluster");
1260   if (!branch) {
1261     AliError("Can't get the branch !");
1262     return 1;
1263   }
1264   branch->SetAddress(&clusterArray);
1265
1266   if(!fClusters){
1267         array = new TClonesArray("AliTRDcluster", nsize);
1268         array->SetOwner(kTRUE);
1269   }
1270
1271   // Loop through all entries in the tree
1272   Int_t nEntries   = (Int_t) clusterTree->GetEntries();
1273   Int_t nbytes     = 0;
1274   Int_t ncl        = 0;
1275   AliTRDcluster *c = 0x0;
1276   for (Int_t iEntry = 0; iEntry < nEntries; iEntry++) {
1277     // Import the tree
1278     nbytes += clusterTree->GetEvent(iEntry);
1279
1280     // Get the number of points in the detector
1281     Int_t nCluster = clusterArray->GetEntriesFast();
1282     for (Int_t iCluster = 0; iCluster < nCluster; iCluster++) {
1283       if(!(c = (AliTRDcluster *) clusterArray->UncheckedAt(iCluster))) continue;
1284                         c->SetInChamber();
1285       new((*fClusters)[ncl++]) AliTRDcluster(*c);
1286       clusterArray->RemoveAt(iCluster);
1287     }
1288
1289   }
1290   delete clusterArray;
1291
1292   return 0;
1293 }
1294
1295 //_____________________________________________________________________________
1296 Int_t AliTRDtrackerV1::LoadClusters(TTree *cTree)
1297 {
1298   //
1299   // Fills clusters into TRD tracking_sectors
1300   // Note that the numbering scheme for the TRD tracking_sectors
1301   // differs from that of TRD sectors
1302   //
1303
1304
1305   if (ReadClusters(fClusters, cTree)) {
1306     AliError("Problem with reading the clusters !");
1307     return 1;
1308   }
1309   Int_t ncl  = fClusters->GetEntriesFast(), nin = 0;
1310         if(!ncl){
1311         AliInfo("Clusters 0");
1312                 return 1;
1313         }
1314
1315   Int_t icl = ncl;
1316   while (icl--) {
1317     AliTRDcluster *c = (AliTRDcluster *) fClusters->UncheckedAt(icl);
1318                 if(c->IsInChamber()) nin++;
1319     Int_t detector       = c->GetDetector();
1320     Int_t sector         = fGeom->GetSector(detector);
1321     Int_t stack          = fGeom->GetChamber(detector);
1322     Int_t plane          = fGeom->GetPlane(detector);
1323
1324                 fTrSec[sector].GetChamber(stack, plane, kTRUE)->InsertCluster(c, icl);
1325   }
1326   AliInfo(Form("Clusters %d in %6.2f %%", ncl, 100.*float(nin)/ncl));
1327
1328         for(int isector =0; isector<AliTRDgeometry::kNsect; isector++){
1329                 if(!fTrSec[isector].GetNChambers()) continue;
1330                 fTrSec[isector].Init();
1331   }
1332
1333   return 0;
1334 }
1335
1336
1337 //____________________________________________________________________
1338 void AliTRDtrackerV1::UnloadClusters()
1339 {
1340   //
1341   // Clears the arrays of clusters and tracks. Resets sectors and timebins
1342   //
1343
1344         if(fTracks) fTracks->Delete();
1345   if(fTracklets) fTracklets->Delete();
1346   if(fClusters) fClusters->Delete();
1347
1348   for (int i = 0; i < AliTRDgeometry::kNsect; i++) fTrSec[i].Clear();
1349
1350         // Increment the Event Number
1351         AliTRDtrackerDebug::SetEventNumber(AliTRDtrackerDebug::GetEventNumber()  + 1);
1352 }
1353
1354 //_____________________________________________________________________________
1355 Bool_t AliTRDtrackerV1::AdjustSector(AliTRDtrackV1 *track)
1356 {
1357   //
1358   // Rotates the track when necessary
1359   //
1360
1361   Double_t alpha = AliTRDgeometry::GetAlpha();
1362   Double_t y     = track->GetY();
1363   Double_t ymax  = track->GetX()*TMath::Tan(0.5*alpha);
1364
1365   if      (y >  ymax) {
1366     if (!track->Rotate( alpha)) {
1367       return kFALSE;
1368     }
1369   }
1370   else if (y < -ymax) {
1371     if (!track->Rotate(-alpha)) {
1372       return kFALSE;
1373     }
1374   }
1375
1376   return kTRUE;
1377
1378 }
1379
1380
1381 //____________________________________________________________________
1382 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(AliTRDtrackV1 *track, Int_t p, Int_t &idx)
1383 {
1384 // Find tracklet for TRD track <track>
1385 // Parameters
1386 // - track
1387 // - sector
1388 // - plane
1389 // - index
1390 // Output
1391 // tracklet
1392 // index
1393 // Detailed description
1394 //
1395         idx = track->GetTrackletIndex(p);
1396         AliTRDseedV1 *tracklet = idx<0 ? 0x0 : (AliTRDseedV1*)fTracklets->UncheckedAt(idx);
1397
1398         return tracklet;
1399 }
1400
1401 //____________________________________________________________________
1402 Int_t AliTRDtrackerV1::SetTracklet(AliTRDseedV1 *tracklet)
1403 {
1404 // Add this tracklet to the list of tracklets stored in the tracker
1405 //
1406 // Parameters
1407 //   - tracklet : pointer to the tracklet to be added to the list
1408 //
1409 // Output
1410 //   - the index of the new tracklet in the tracker tracklets list
1411 //
1412 // Detailed description
1413 // Build the tracklets list if it is not yet created (late initialization)
1414 // and adds the new tracklet to the list.
1415 //
1416         if(!fTracklets){
1417                 fTracklets = new TClonesArray("AliTRDseedV1", AliTRDgeometry::Nsect()*kMaxTracksStack);
1418                 fTracklets->SetOwner(kTRUE);
1419         }
1420         Int_t nentries = fTracklets->GetEntriesFast();
1421         new ((*fTracklets)[nentries]) AliTRDseedV1(*tracklet);
1422         return nentries;
1423 }
1424
1425 //____________________________________________________________________
1426 Int_t AliTRDtrackerV1::Clusters2TracksSM(Int_t sector, AliESDEvent *esd)
1427 {
1428   //
1429   // Steer tracking for one SM.
1430   //
1431   // Parameters :
1432   //   sector  : Array of (SM) propagation layers containing clusters
1433   //   esd     : The current ESD event. On output it contains the also
1434   //             the ESD (TRD) tracks found in this SM.
1435   //
1436   // Output :
1437   //   Number of tracks found in this TRD supermodule.
1438   //
1439   // Detailed description
1440   //
1441   // 1. Unpack AliTRDpropagationLayers objects for each stack.
1442   // 2. Launch stack tracking.
1443   //    See AliTRDtrackerV1::Clusters2TracksStack() for details.
1444   // 3. Pack results in the ESD event.
1445   //
1446
1447         // allocate space for esd tracks in this SM
1448         TClonesArray esdTrackList("AliESDtrack", 2*kMaxTracksStack);
1449         esdTrackList.SetOwner();
1450
1451         Int_t nTracks   = 0;
1452         Int_t nChambers = 0;
1453         AliTRDtrackingChamber **stack = 0x0, *chamber = 0x0;
1454         for(int istack = 0; istack<AliTRDgeometry::kNcham; istack++){
1455                 if(!(stack = fTrSec[sector].GetStack(istack))) continue;
1456                 nChambers = 0;
1457                 for(int iplane=0; iplane<AliTRDgeometry::kNplan; iplane++){
1458                         if(!(chamber = stack[iplane])) continue;
1459                         if(chamber->GetNClusters() < fgNTimeBins * AliTRDReconstructor::RecoParam()->GetFindableClusters()) continue;
1460                         nChambers++;
1461                         //AliInfo(Form("sector %d stack %d plane %d clusters %d", sector, istack, iplane, chamber->GetNClusters()));
1462                 }
1463                 if(nChambers < 4) continue;
1464                 //AliInfo(Form("Doing stack %d", istack));
1465                 nTracks += Clusters2TracksStack(stack, &esdTrackList);
1466         }
1467         //AliInfo(Form("Found %d tracks in SM %d [%d]\n", nTracks, sector, esd->GetNumberOfTracks()));
1468
1469         for(int itrack=0; itrack<nTracks; itrack++)
1470           esd->AddTrack((AliESDtrack*)esdTrackList[itrack]);
1471
1472         // Reset Track and Candidate Number
1473         AliTRDtrackerDebug::SetCandidateNumber(0);
1474         AliTRDtrackerDebug::SetTrackNumber(0);
1475         return nTracks;
1476 }
1477
1478 //____________________________________________________________________
1479 Int_t AliTRDtrackerV1::Clusters2TracksStack(AliTRDtrackingChamber **stack, TClonesArray *esdTrackList)
1480 {
1481   //
1482   // Make tracks in one TRD stack.
1483   //
1484   // Parameters :
1485   //   layer  : Array of stack propagation layers containing clusters
1486   //   esdTrackList  : Array of ESD tracks found by the stand alone tracker.
1487   //                   On exit the tracks found in this stack are appended.
1488   //
1489   // Output :
1490   //   Number of tracks found in this stack.
1491   //
1492   // Detailed description
1493   //
1494   // 1. Find the 3 most useful seeding chambers. See BuildSeedingConfigs() for details.
1495   // 2. Steer AliTRDtrackerV1::MakeSeeds() for 3 seeding layer configurations.
1496   //    See AliTRDtrackerV1::MakeSeeds() for more details.
1497   // 3. Arrange track candidates in decreasing order of their quality
1498   // 4. Classify tracks in 5 categories according to:
1499   //    a) number of layers crossed
1500   //    b) track quality
1501   // 5. Sign clusters by tracks in decreasing order of track quality
1502   // 6. Build AliTRDtrack out of seeding tracklets
1503   // 7. Cook MC label
1504   // 8. Build ESD track and register it to the output list
1505   //
1506
1507         AliTRDtrackingChamber *chamber = 0x0;
1508         AliTRDseedV1 sseed[kMaxTracksStack*6]; // to be initialized
1509         Int_t pars[4]; // MakeSeeds parameters
1510
1511         //Double_t alpha = AliTRDgeometry::GetAlpha();
1512         //Double_t shift = .5 * alpha;
1513         Int_t configs[kNConfigs];
1514
1515         // Build initial seeding configurations
1516         Double_t quality = BuildSeedingConfigs(stack, configs);
1517         if(AliTRDReconstructor::StreamLevel() > 1){
1518         AliInfo(Form("Plane config %d %d %d Quality %f"
1519     , configs[0], configs[1], configs[2], quality));
1520         }
1521
1522         // Initialize contors
1523         Int_t ntracks,      // number of TRD track candidates
1524               ntracks1,     // number of registered TRD tracks/iter
1525               ntracks2 = 0; // number of all registered TRD tracks in stack
1526         fSieveSeeding = 0;
1527         do{
1528                 // Loop over seeding configurations
1529                 ntracks = 0; ntracks1 = 0;
1530                 for (Int_t iconf = 0; iconf<3; iconf++) {
1531                         pars[0] = configs[iconf];
1532                         pars[1] = ntracks;
1533                         ntracks = MakeSeeds(stack, &sseed[6*ntracks], pars);
1534                         if(ntracks == kMaxTracksStack) break;
1535                 }
1536                 if(AliTRDReconstructor::StreamLevel() > 1) AliInfo(Form("Candidate TRD tracks %d in iteration %d.", ntracks, fSieveSeeding));
1537
1538                 if(!ntracks) break;
1539
1540                 // Sort the seeds according to their quality
1541                 Int_t sort[kMaxTracksStack];
1542                 TMath::Sort(ntracks, fTrackQuality, sort, kTRUE);
1543
1544                 // Initialize number of tracks so far and logic switches
1545                 Int_t ntracks0 = esdTrackList->GetEntriesFast();
1546                 Bool_t signedTrack[kMaxTracksStack];
1547                 Bool_t fakeTrack[kMaxTracksStack];
1548                 for (Int_t i=0; i<ntracks; i++){
1549                         signedTrack[i] = kFALSE;
1550                         fakeTrack[i] = kFALSE;
1551                 }
1552                 //AliInfo("Selecting track candidates ...");
1553
1554                 // Sieve clusters in decreasing order of track quality
1555                 Double_t trackParams[7];
1556 //              AliTRDseedV1 *lseed = 0x0;
1557                 Int_t jSieve = 0, candidates;
1558                 do{
1559                         //AliInfo(Form("\t\tITER = %i ", jSieve));
1560
1561                         // Check track candidates
1562                         candidates = 0;
1563                         for (Int_t itrack = 0; itrack < ntracks; itrack++) {
1564                                 Int_t trackIndex = sort[itrack];
1565                                 if (signedTrack[trackIndex] || fakeTrack[trackIndex]) continue;
1566
1567
1568                                 // Calculate track parameters from tracklets seeds
1569                                 Int_t labelsall[1000];
1570                                 Int_t nlabelsall = 0;
1571                                 Int_t naccepted  = 0;
1572                                 Int_t ncl        = 0;
1573                                 Int_t nused      = 0;
1574                                 Int_t nlayers    = 0;
1575                                 Int_t findable   = 0;
1576                                 for (Int_t jLayer = 0; jLayer < kNPlanes; jLayer++) {
1577                                         Int_t jseed = kNPlanes*trackIndex+jLayer;
1578                                         if(!sseed[jseed].IsOK()) continue;
1579                                         if (TMath::Abs(sseed[jseed].GetYref(0) / sseed[jseed].GetX0()) < 0.15) findable++;
1580
1581                                         sseed[jseed].UpdateUsed();
1582                                         ncl   += sseed[jseed].GetN2();
1583                                         nused += sseed[jseed].GetNUsed();
1584                                         nlayers++;
1585
1586                                         // Cooking label
1587                                         for (Int_t itime = 0; itime < fgNTimeBins; itime++) {
1588                                                 if(!sseed[jseed].IsUsable(itime)) continue;
1589                                                 naccepted++;
1590                                                 Int_t tindex = 0, ilab = 0;
1591                                                 while(ilab<3 && (tindex = sseed[jseed].GetClusters(itime)->GetLabel(ilab)) >= 0){
1592                                                         labelsall[nlabelsall++] = tindex;
1593                                                         ilab++;
1594                                                 }
1595                                         }
1596                                 }
1597                                 // Filter duplicated tracks
1598                                 if (nused > 30){
1599                                         //printf("Skip %d nused %d\n", trackIndex, nused);
1600                                         fakeTrack[trackIndex] = kTRUE;
1601                                         continue;
1602                                 }
1603                                 if (Float_t(nused)/ncl >= .25){
1604                                         //printf("Skip %d nused/ncl >= .25\n", trackIndex);
1605                                         fakeTrack[trackIndex] = kTRUE;
1606                                         continue;
1607                                 }
1608
1609                                 // Classify tracks
1610                                 Bool_t skip = kFALSE;
1611                                 switch(jSieve){
1612                                 case 0:
1613                                         if(nlayers < 6) {skip = kTRUE; break;}
1614                                         if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
1615                                         break;
1616
1617                                 case 1:
1618                                         if(nlayers < findable){skip = kTRUE; break;}
1619                                         if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -4.){skip = kTRUE; break;}
1620                                         break;
1621
1622                                 case 2:
1623                                         if ((nlayers == findable) || (nlayers == 6)) { skip = kTRUE; break;}
1624                                         if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -6.0){skip = kTRUE; break;}
1625                                         break;
1626
1627                                 case 3:
1628                                         if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
1629                                         break;
1630
1631                                 case 4:
1632                                         if (nlayers == 3){skip = kTRUE; break;}
1633                                         //if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) - nused/(nlayers-3.0) < -15.0){skip = kTRUE; break;}
1634                                         break;
1635                                 }
1636                                 if(skip){
1637                                         candidates++;
1638                                         //printf("REJECTED : %d [%d] nlayers %d trackQuality = %e nused %d\n", itrack, trackIndex, nlayers, fTrackQuality[trackIndex], nused);
1639                                         continue;
1640                                 }
1641                                 signedTrack[trackIndex] = kTRUE;
1642
1643
1644                                 // Build track label - what happens if measured data ???
1645                                 Int_t labels[1000];
1646                                 Int_t outlab[1000];
1647                                 Int_t nlab = 0;
1648                                 for (Int_t iLayer = 0; iLayer < 6; iLayer++) {
1649                                         Int_t jseed = kNPlanes*trackIndex+iLayer;
1650                                         if(!sseed[jseed].IsOK()) continue;
1651                                         for(int ilab=0; ilab<2; ilab++){
1652                                                 if(sseed[jseed].GetLabels(ilab) < 0) continue;
1653                                                 labels[nlab] = sseed[jseed].GetLabels(ilab);
1654                                                 nlab++;
1655                                         }
1656                                 }
1657                                 Freq(nlab,labels,outlab,kFALSE);
1658                                 Int_t   label     = outlab[0];
1659                                 Int_t   frequency = outlab[1];
1660                                 Freq(nlabelsall,labelsall,outlab,kFALSE);
1661                                 Int_t   label1    = outlab[0];
1662                                 Int_t   label2    = outlab[2];
1663                                 Float_t fakeratio = (naccepted - outlab[1]) / Float_t(naccepted);
1664
1665
1666                                 // Sign clusters
1667                                 AliTRDcluster *cl = 0x0; Int_t clusterIndex = -1;
1668                                 for (Int_t jLayer = 0; jLayer < 6; jLayer++) {
1669                                         Int_t jseed = kNPlanes*trackIndex+jLayer;
1670                                         if(!sseed[jseed].IsOK()) continue;
1671                                         if(TMath::Abs(sseed[jseed].GetYfit(1) - sseed[jseed].GetYfit(1)) >= .2) continue; // check this condition with Marian
1672                                         sseed[jseed].UseClusters();
1673                                         if(!cl){
1674                                                 Int_t ic = 0;
1675                                                 while(!(cl = sseed[jseed].GetClusters(ic))) ic++;
1676                                                 clusterIndex =  sseed[jseed].GetIndexes(ic);
1677                                         }
1678                                 }
1679                                 if(!cl) continue;
1680
1681
1682                                 // Build track parameters
1683                                 AliTRDseedV1 *lseed =&sseed[trackIndex*6];
1684                                 Int_t idx = 0;
1685                                 while(idx<3 && !lseed->IsOK()) {
1686                                         idx++;
1687                                         lseed++;
1688                                 }
1689                                 Double_t cR = lseed->GetC();
1690                                 trackParams[1] = lseed->GetYref(0);
1691                                 trackParams[2] = lseed->GetZref(0);
1692                                 trackParams[3] = lseed->GetX0() * cR - TMath::Sin(TMath::ATan(lseed->GetYref(1)));
1693                                 trackParams[4] = lseed->GetZref(1) / TMath::Sqrt(1. + lseed->GetYref(1) * lseed->GetYref(1));
1694                                 trackParams[5] = cR;
1695                                 trackParams[0] = lseed->GetX0();
1696                                 Int_t ich = 0; while(!(chamber = stack[ich])) ich++;
1697                                 trackParams[6] = fGeom->GetSector(chamber->GetDetector());/* *alpha+shift;      // Supermodule*/
1698
1699                                 if(AliTRDReconstructor::StreamLevel() > 1){
1700                                         AliInfo(Form("Track %d [%d] nlayers %d trackQuality = %e nused %d, yref = %3.3f", itrack, trackIndex, nlayers, fTrackQuality[trackIndex], nused, trackParams[1]));
1701
1702                                         Int_t nclusters = 0;
1703                                         AliTRDseedV1 *dseed[6];
1704                                         for(int is=0; is<6; is++){
1705                                                 dseed[is] = new AliTRDseedV1(sseed[trackIndex*6+is]);
1706                                                 dseed[is]->SetOwner();
1707                                                 nclusters += sseed[is].GetN2();
1708                                         }
1709                                         //Int_t eventNrInFile = esd->GetEventNumberInFile();
1710                                         //AliInfo(Form("Number of clusters %d.", nclusters));
1711                                         Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1712                                         Int_t trackNumber = AliTRDtrackerDebug::GetTrackNumber();
1713                                         Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1714                                         TTreeSRedirector &cstreamer = *fgDebugStreamer;
1715                                         cstreamer << "Clusters2TracksStack"
1716                                                 << "EventNumber="               << eventNumber
1717                                                 << "TrackNumber="               << trackNumber
1718                                                 << "CandidateNumber="   << candidateNumber
1719                                                 << "Iter="                              << fSieveSeeding
1720                                                 << "Like="                              << fTrackQuality[trackIndex]
1721                                                 << "S0.="                               << dseed[0]
1722                                                 << "S1.="                               << dseed[1]
1723                                                 << "S2.="                               << dseed[2]
1724                                                 << "S3.="                               << dseed[3]
1725                                                 << "S4.="                               << dseed[4]
1726                                                 << "S5.="                               << dseed[5]
1727                                                 << "p0="                                << trackParams[0]
1728                                                 << "p1="                                << trackParams[1]
1729                                                 << "p2="                                << trackParams[2]
1730                                                 << "p3="                                << trackParams[3]
1731                                                 << "p4="                                << trackParams[4]
1732                                                 << "p5="                                << trackParams[5]
1733                                                 << "p6="                                << trackParams[6]
1734                                                 << "Label="                             << label
1735                                                 << "Label1="                    << label1
1736                                                 << "Label2="                    << label2
1737                                                 << "FakeRatio="                 << fakeratio
1738                                                 << "Freq="                              << frequency
1739                                                 << "Ncl="                               << ncl
1740                                                 << "NLayers="                   << nlayers
1741                                                 << "Findable="                  << findable
1742                                                 << "NUsed="                             << nused
1743                                                 << "\n";
1744                                         }
1745
1746                                 AliTRDtrackV1 *track = MakeTrack(&sseed[trackIndex*kNPlanes], trackParams);
1747                                 if(!track){
1748                                         //AliWarning("Fail to build a TRD Track.");
1749                                         continue;
1750                                 }
1751                                 //AliInfo("End of MakeTrack()");
1752                                 AliESDtrack esdTrack;
1753                                 esdTrack.UpdateTrackParams(track, AliESDtrack::kTRDout);
1754                                 esdTrack.SetLabel(track->GetLabel());
1755                                 new ((*esdTrackList)[ntracks0++]) AliESDtrack(esdTrack);
1756                                 ntracks1++;
1757                                 AliTRDtrackerDebug::SetTrackNumber(AliTRDtrackerDebug::GetTrackNumber() + 1);
1758                         }
1759
1760                         jSieve++;
1761                 } while(jSieve<5 && candidates); // end track candidates sieve
1762                 if(!ntracks1) break;
1763
1764                 // increment counters
1765                 ntracks2 += ntracks1;
1766                 fSieveSeeding++;
1767
1768                 // Rebuild plane configurations and indices taking only unused clusters into account
1769                 quality = BuildSeedingConfigs(stack, configs);
1770                 if(quality < 1.E-7) break; //AliTRDReconstructor::RecoParam()->GetPlaneQualityThreshold()) break;
1771
1772                 for(Int_t ip = 0; ip < kNPlanes; ip++){
1773                         if(!(chamber = stack[ip])) continue;
1774                         chamber->Build(fGeom);//Indices(fSieveSeeding);
1775                 }
1776
1777                 if(AliTRDReconstructor::StreamLevel() > 1){
1778                         AliInfo(Form("Sieve level %d Plane config %d %d %d Quality %f", fSieveSeeding, configs[0], configs[1], configs[2], quality));
1779                 }
1780         } while(fSieveSeeding<10); // end stack clusters sieve
1781
1782
1783
1784         //AliInfo(Form("Registered TRD tracks %d in stack %d.", ntracks2, pars[1]));
1785
1786         return ntracks2;
1787 }
1788
1789 //___________________________________________________________________
1790 Double_t AliTRDtrackerV1::BuildSeedingConfigs(AliTRDtrackingChamber **stack, Int_t *configs)
1791 {
1792   //
1793   // Assign probabilities to chambers according to their
1794   // capability of producing seeds.
1795   //
1796   // Parameters :
1797   //
1798   //   layers : Array of stack propagation layers for all 6 chambers in one stack
1799   //   configs : On exit array of configuration indexes (see GetSeedingConfig()
1800   // for details) in the decreasing order of their seeding probabilities.
1801   //
1802   // Output :
1803   //
1804   //  Return top configuration quality
1805   //
1806   // Detailed description:
1807   //
1808   // To each chamber seeding configuration (see GetSeedingConfig() for
1809   // the list of all configurations) one defines 2 quality factors:
1810   //  - an apriori topological quality (see GetSeedingConfig() for details) and
1811   //  - a data quality based on the uniformity of the distribution of
1812   //    clusters over the x range (time bins population). See CookChamberQA() for details.
1813   // The overall chamber quality is given by the product of this 2 contributions.
1814   //
1815
1816         Double_t chamberQ[kNPlanes];
1817         AliTRDtrackingChamber *chamber = 0x0;
1818         for(int iplane=0; iplane<kNPlanes; iplane++){
1819                 if(!(chamber = stack[iplane])) continue;
1820                 chamberQ[iplane] = (chamber = stack[iplane]) ?  chamber->GetQuality() : 0.;
1821         }
1822
1823         Double_t tconfig[kNConfigs];
1824         Int_t planes[4];
1825         for(int iconf=0; iconf<kNConfigs; iconf++){
1826                 GetSeedingConfig(iconf, planes);
1827                 tconfig[iconf] = fgTopologicQA[iconf];
1828                 for(int iplane=0; iplane<4; iplane++) tconfig[iconf] *= chamberQ[planes[iplane]];
1829         }
1830
1831         TMath::Sort(kNConfigs, tconfig, configs, kTRUE);
1832 //      AliInfo(Form("q[%d] = %f", configs[0], tconfig[configs[0]]));
1833 //      AliInfo(Form("q[%d] = %f", configs[1], tconfig[configs[1]]));
1834 //      AliInfo(Form("q[%d] = %f", configs[2], tconfig[configs[2]]));
1835
1836         return tconfig[configs[0]];
1837 }
1838
1839 //____________________________________________________________________
1840 Int_t AliTRDtrackerV1::MakeSeeds(AliTRDtrackingChamber **stack, AliTRDseedV1 *sseed, Int_t *ipar)
1841 {
1842   //
1843   // Make tracklet seeds in the TRD stack.
1844   //
1845   // Parameters :
1846   //   layers : Array of stack propagation layers containing clusters
1847   //   sseed  : Array of empty tracklet seeds. On exit they are filled.
1848   //   ipar   : Control parameters:
1849   //       ipar[0] -> seeding chambers configuration
1850   //       ipar[1] -> stack index
1851   //       ipar[2] -> number of track candidates found so far
1852   //
1853   // Output :
1854   //   Number of tracks candidates found.
1855   //
1856   // Detailed description
1857   //
1858   // The following steps are performed:
1859   // 1. Select seeding layers from seeding chambers
1860   // 2. Select seeding clusters from the seeding AliTRDpropagationLayerStack.
1861   //   The clusters are taken from layer 3, layer 0, layer 1 and layer 2, in
1862   //   this order. The parameters controling the range of accepted clusters in
1863   //   layer 0, 1, and 2 are defined in AliTRDchamberTimeBin::BuildCond().
1864   // 3. Helix fit of the cluster set. (see AliTRDtrackerFitter::FitRieman(AliTRDcluster**))
1865   // 4. Initialize seeding tracklets in the seeding chambers.
1866   // 5. Filter 0.
1867   //   Chi2 in the Y direction less than threshold ... (1./(3. - sLayer))
1868   //   Chi2 in the Z direction less than threshold ... (1./(3. - sLayer))
1869   // 6. Attach clusters to seeding tracklets and find linear approximation of
1870   //   the tracklet (see AliTRDseedV1::AttachClustersIter()). The number of used
1871   //   clusters used by current seeds should not exceed ... (25).
1872   // 7. Filter 1.
1873   //   All 4 seeding tracklets should be correctly constructed (see
1874   //   AliTRDseedV1::AttachClustersIter())
1875   // 8. Helix fit of the seeding tracklets
1876   // 9. Filter 2.
1877   //   Likelihood calculation of the fit. (See AliTRDtrackerV1::CookLikelihood() for details)
1878   // 10. Extrapolation of the helix fit to the other 2 chambers:
1879   //    a) Initialization of extrapolation tracklet with fit parameters
1880   //    b) Helix fit of tracklets
1881   //    c) Attach clusters and linear interpolation to extrapolated tracklets
1882   //    d) Helix fit of tracklets
1883   // 11. Improve seeding tracklets quality by reassigning clusters.
1884   //      See AliTRDtrackerV1::ImproveSeedQuality() for details.
1885   // 12. Helix fit of all 6 seeding tracklets and chi2 calculation
1886   // 13. Hyperplane fit and track quality calculation. See AliTRDtrackerFitter::FitHyperplane() for details.
1887   // 14. Cooking labels for tracklets. Should be done only for MC
1888   // 15. Register seeds.
1889   //
1890
1891         AliTRDtrackingChamber *chamber = 0x0;
1892         AliTRDcluster *c[4] = {0x0, 0x0, 0x0, 0x0}; // initilize seeding clusters
1893         AliTRDseedV1 *cseed = &sseed[0]; // initialize tracklets for first track
1894         Int_t ncl, mcl; // working variable for looping over clusters
1895         Int_t index[AliTRDchamberTimeBin::kMaxClustersLayer], jndex[AliTRDchamberTimeBin::kMaxClustersLayer];
1896         // chi2 storage
1897         // chi2[0] = tracklet chi2 on the Z direction
1898         // chi2[1] = tracklet chi2 on the R direction
1899         Double_t chi2[4];
1900
1901
1902         // this should be data member of AliTRDtrack
1903         Double_t seedQuality[kMaxTracksStack];
1904
1905         // unpack control parameters
1906         Int_t config  = ipar[0];
1907         Int_t ntracks = ipar[1];
1908         Int_t planes[kNSeedPlanes]; GetSeedingConfig(config, planes);
1909
1910         // Init chambers geometry
1911         Int_t ic = 0; while(!(chamber = stack[ic])) ic++;
1912         Int_t istack = fGeom->GetChamber(chamber->GetDetector());
1913         Double_t hL[kNPlanes];       // Tilting angle
1914         Float_t padlength[kNPlanes]; // pad lenghts
1915         AliTRDpadPlane *pp = 0x0;
1916         for(int iplane=0; iplane<kNPlanes; iplane++){
1917                 pp                = fGeom->GetPadPlane(iplane, istack);
1918                 hL[iplane]        = TMath::Tan(-TMath::DegToRad()*pp->GetTiltingAngle());
1919                 padlength[iplane] = pp->GetLengthIPad();
1920         }
1921
1922         if(AliTRDReconstructor::StreamLevel() > 1){
1923                 AliInfo(Form("Making seeds Stack[%d] Config[%d] Tracks[%d]...", istack, config, ntracks));
1924         }
1925
1926         Int_t nlayers = 0;
1927         AliTRDchamberTimeBin *layer[] = {0x0, 0x0, 0x0, 0x0};
1928         for(int isl=0; isl<kNSeedPlanes; isl++){
1929                 if(!(chamber = stack[planes[isl]])) continue;
1930                 if(!(layer[isl] = chamber->GetSeedingLayer(fGeom))) continue;
1931                 nlayers++;
1932                 //AliInfo(Form("seeding plane %d clusters %d", planes[isl], Int_t(*layer[isl])));
1933         }
1934         if(nlayers < 4) return 0;
1935
1936
1937         // Start finding seeds
1938         Double_t cond0[4], cond1[4], cond2[4];
1939         Int_t icl = 0;
1940         while((c[3] = (*layer[3])[icl++])){
1941                 if(!c[3]) continue;
1942                 layer[0]->BuildCond(c[3], cond0, 0);
1943                 layer[0]->GetClusters(cond0, index, ncl);
1944                 //printf("Found c[3] candidates 0 %d\n", ncl);
1945                 Int_t jcl = 0;
1946                 while(jcl<ncl) {
1947                         c[0] = (*layer[0])[index[jcl++]];
1948                         if(!c[0]) continue;
1949                         Double_t dx    = c[3]->GetX() - c[0]->GetX();
1950                         Double_t theta = (c[3]->GetZ() - c[0]->GetZ())/dx;
1951                         Double_t phi   = (c[3]->GetY() - c[0]->GetY())/dx;
1952                         layer[1]->BuildCond(c[0], cond1, 1, theta, phi);
1953                         layer[1]->GetClusters(cond1, jndex, mcl);
1954                         //printf("Found c[0] candidates 1 %d\n", mcl);
1955
1956                         Int_t kcl = 0;
1957                         while(kcl<mcl) {
1958                                 c[1] = (*layer[1])[jndex[kcl++]];
1959                                 if(!c[1]) continue;
1960                                 layer[2]->BuildCond(c[1], cond2, 2, theta, phi);
1961                                 c[2] = layer[2]->GetNearestCluster(cond2);
1962                                 //printf("Found c[1] candidate 2 %p\n", c[2]);
1963                                 if(!c[2]) continue;
1964
1965 //                              AliInfo("Seeding clusters found. Building seeds ...");
1966 //                              for(Int_t i = 0; i < kNSeedPlanes; i++) printf("%i. coordinates: x = %6.3f, y = %6.3f, z = %6.3f\n", i, c[i]->GetX(), c[i]->GetY(), c[i]->GetZ());
1967
1968                                 for (Int_t il = 0; il < 6; il++) cseed[il].Reset();
1969
1970                                 FitRieman(c, chi2);
1971
1972                                 AliTRDseedV1 *tseed = 0x0;
1973                                 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
1974                                         Int_t jLayer = planes[iLayer];
1975                                         tseed = &cseed[jLayer];
1976                                         tseed->SetPlane(jLayer);
1977                                         tseed->SetTilt(hL[jLayer]);
1978                                         tseed->SetPadLength(padlength[jLayer]);
1979                                         tseed->SetX0(stack[jLayer]->GetX());
1980                                         tseed->Init(GetRiemanFitter());
1981                                 }
1982
1983                                 Bool_t isFake = kFALSE;
1984                                 if(AliTRDReconstructor::StreamLevel() >= 2){
1985                                         if (c[0]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
1986                                         if (c[1]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
1987                                         if (c[2]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
1988
1989                                         Double_t xpos[4];
1990                                         for(Int_t l = 0; l < kNSeedPlanes; l++) xpos[l] = layer[l]->GetX();
1991                                         Float_t yref[4];
1992                                         for(int il=0; il<4; il++) yref[il] = cseed[planes[il]].GetYref(0);
1993                                         Int_t ll = c[3]->GetLabel(0);
1994                                         Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1995                                         Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1996                                         AliRieman *rim = GetRiemanFitter();
1997                                         TTreeSRedirector &cs0 = *fgDebugStreamer;
1998                                         cs0 << "MakeSeeds0"
1999                                                 <<"EventNumber="                << eventNumber
2000                                                 <<"CandidateNumber="    << candidateNumber
2001                                                 <<"isFake="                             << isFake
2002                                                 <<"config="                             << config
2003                                                 <<"label="                              << ll
2004                                                 <<"chi2z="                              << chi2[0]
2005                                                 <<"chi2y="                              << chi2[1]
2006                                                 <<"Y2exp="                              << cond2[0]
2007                                                 <<"Z2exp="                              << cond2[1]
2008                                             <<"X0="                                     << xpos[0] //layer[sLayer]->GetX()
2009                                             <<"X1="                                     << xpos[1] //layer[sLayer + 1]->GetX()
2010                                             <<"X2="                                     << xpos[2] //layer[sLayer + 2]->GetX()
2011                                             <<"X3="                                     << xpos[3] //layer[sLayer + 3]->GetX()
2012                                                 <<"yref0="                              << yref[0]
2013                                                 <<"yref1="                              << yref[1]
2014                                                 <<"yref2="                              << yref[2]
2015                                                 <<"yref3="                              << yref[3]
2016                                                 <<"c0.="                                << c[0]
2017                                                 <<"c1.="                                << c[1]
2018                                                 <<"c2.="                                << c[2]
2019                                                 <<"c3.="                                << c[3]
2020                                                 <<"Seed0.="                             << &cseed[planes[0]]
2021                                                 <<"Seed1.="                             << &cseed[planes[1]]
2022                                                 <<"Seed2.="                             << &cseed[planes[2]]
2023                                                 <<"Seed3.="                             << &cseed[planes[3]]
2024                                                 <<"RiemanFitter.="              << rim
2025                                                 <<"\n";
2026                                 }
2027
2028                                 if(chi2[0] > AliTRDReconstructor::RecoParam()->GetChi2Z()/*7./(3. - sLayer)*//*iter*/){
2029                                         //AliInfo(Form("Failed chi2 filter on chi2Z [%f].", chi2[0]));
2030                                         AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2031                                         continue;
2032                                 }
2033                                 if(chi2[1] > AliTRDReconstructor::RecoParam()->GetChi2Y()/*1./(3. - sLayer)*//*iter*/){
2034                                         //AliInfo(Form("Failed chi2 filter on chi2Y [%f].", chi2[1]));
2035                                         AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2036                                         continue;
2037                                 }
2038                                 //AliInfo("Passed chi2 filter.");
2039
2040                                 // try attaching clusters to tracklets
2041                                 Int_t nUsedCl = 0;
2042                                 Int_t nlayers = 0;
2043                                 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2044                                         Int_t jLayer = planes[iLayer];
2045                                         if(!cseed[jLayer].AttachClustersIter(stack[jLayer], 5., kFALSE, c[iLayer])) continue;
2046                                         nUsedCl += cseed[jLayer].GetNUsed();
2047                                         if(nUsedCl > 25) break;
2048                                         nlayers++;
2049                                 }
2050                                 if(nlayers < kNSeedPlanes){
2051                                         //AliInfo(Form("Failed updating all seeds %d [%d].", nlayers, kNSeedPlanes));
2052                                         AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2053                                         continue;
2054                                 }
2055                                 // fit tracklets and cook likelihood
2056                                 FitTiltedRieman(&cseed[0], kTRUE);// Update Seeds and calculate Likelihood
2057                                 chi2[0] = GetChi2Y(&cseed[0]);
2058                                 chi2[1] = GetChi2Z(&cseed[0]);
2059                                 //Chi2 definitions in testing stage
2060                                 //chi2[0] = GetChi2YTest(&cseed[0]);
2061                                 //chi2[1] = GetChi2ZTest(&cseed[0]);
2062                                 Double_t like = CookLikelihood(&cseed[0], planes, chi2); // to be checked
2063
2064                                 if (TMath::Log(1.E-9 + like) < AliTRDReconstructor::RecoParam()->GetTrackLikelihood()){
2065                                         //AliInfo(Form("Failed likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2066                                         AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2067                                         continue;
2068                                 }
2069                                 //AliInfo(Form("Passed likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2070
2071                                 // book preliminary results
2072                                 seedQuality[ntracks] = like;
2073                                 fSeedLayer[ntracks]  = config;/*sLayer;*/
2074
2075                                 // attach clusters to the extrapolation seeds
2076                                 Int_t lextrap[2];
2077                                 GetExtrapolationConfig(config, lextrap);
2078                                 Int_t nusedf   = 0; // debug value
2079                                 for(int iLayer=0; iLayer<2; iLayer++){
2080                                         Int_t jLayer = lextrap[iLayer];
2081                                         if(!(chamber = stack[jLayer])) continue;
2082
2083                                         // prepare extrapolated seed
2084                                         cseed[jLayer].Reset();
2085                                         cseed[jLayer].SetPlane(jLayer);
2086                                         cseed[jLayer].SetTilt(hL[jLayer]);
2087                                         cseed[jLayer].SetX0(chamber->GetX());
2088                                         cseed[jLayer].SetPadLength(padlength[jLayer]);
2089
2090                                         // fit extrapolated seed
2091                                         if ((jLayer == 0) && !(cseed[1].IsOK())) continue;
2092                                         if ((jLayer == 5) && !(cseed[4].IsOK())) continue;
2093                                         AliTRDseedV1 tseed = cseed[jLayer];
2094                                         if(!tseed.AttachClustersIter(chamber, 1000.)) continue;
2095                                         cseed[jLayer] = tseed;
2096                                         nusedf += cseed[jLayer].GetNUsed(); // debug value
2097                                         FitTiltedRieman(cseed,  kTRUE);
2098                                 }
2099
2100                                 // AliInfo("Extrapolation done.");
2101                                 // Debug Stream containing all the 6 tracklets
2102                                 if(AliTRDReconstructor::StreamLevel() >= 2){
2103                                         TTreeSRedirector &cstreamer = *fgDebugStreamer;
2104                                         TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
2105                                         Int_t eventNumber               = AliTRDtrackerDebug::GetEventNumber();
2106                                         Int_t candidateNumber   = AliTRDtrackerDebug::GetCandidateNumber();
2107                                         cstreamer << "MakeSeeds1"
2108                                                 << "EventNumber="               << eventNumber
2109                                                 << "CandidateNumber="   << candidateNumber
2110                                                 << "S0.="                               << &cseed[0]
2111                                                 << "S1.="                               << &cseed[1]
2112                                                 << "S2.="                               << &cseed[2]
2113                                             << "S3.="                           << &cseed[3]
2114                                             << "S4.="                           << &cseed[4]
2115                                             << "S5.="                           << &cseed[5]
2116                                             << "FitterT.="                      << tiltedRieman
2117                                             << "\n";
2118                                 }
2119
2120                                 if(ImproveSeedQuality(stack, cseed) < 4){
2121                                         AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2122                                         continue;
2123                                 }
2124                                 //AliInfo("Improve seed quality done.");
2125
2126                                 // fit full track and cook likelihoods
2127 //                              Double_t curv = FitRieman(&cseed[0], chi2);
2128 //                              Double_t chi2ZF = chi2[0] / TMath::Max((nlayers - 3.), 1.);
2129 //                              Double_t chi2RF = chi2[1] / TMath::Max((nlayers - 3.), 1.);
2130
2131                                 // do the final track fitting (Once with vertex constraint and once without vertex constraint)
2132                                 Double_t chi2Vals[3];
2133                                 chi2Vals[0] = FitTiltedRieman(&cseed[0], kFALSE);
2134                                 chi2Vals[1] = FitTiltedRiemanConstraint(&cseed[0], GetZ());
2135                                 chi2Vals[2] = GetChi2Z(&cseed[0]) / TMath::Max((nlayers - 3.), 1.);
2136                                 // Chi2 definitions in testing stage
2137                                 //chi2Vals[2] = GetChi2ZTest(&cseed[0]);
2138                                 fTrackQuality[ntracks] = CalculateTrackLikelihood(&cseed[0], &chi2Vals[0]);
2139                                 //AliInfo("Hyperplane fit done\n");
2140
2141                                 // finalize tracklets
2142                                 Int_t labels[12];
2143                                 Int_t outlab[24];
2144                                 Int_t nlab = 0;
2145                                 for (Int_t iLayer = 0; iLayer < 6; iLayer++) {
2146                                         if (!cseed[iLayer].IsOK()) continue;
2147
2148                                         if (cseed[iLayer].GetLabels(0) >= 0) {
2149                                                 labels[nlab] = cseed[iLayer].GetLabels(0);
2150                                                 nlab++;
2151                                         }
2152
2153                                         if (cseed[iLayer].GetLabels(1) >= 0) {
2154                                                 labels[nlab] = cseed[iLayer].GetLabels(1);
2155                                                 nlab++;
2156                                         }
2157                                 }
2158                                 Freq(nlab,labels,outlab,kFALSE);
2159                                 Int_t label     = outlab[0];
2160                                 Int_t frequency = outlab[1];
2161                                 for (Int_t iLayer = 0; iLayer < 6; iLayer++) {
2162                                         cseed[iLayer].SetFreq(frequency);
2163                                         cseed[iLayer].SetChi2Z(chi2[1]);
2164                                 }
2165
2166                                 if(AliTRDReconstructor::StreamLevel() >= 2){
2167                                         TTreeSRedirector &cstreamer = *fgDebugStreamer;
2168                                         Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2169                                         Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2170                                         TLinearFitter *fitterTC = GetTiltedRiemanFitterConstraint();
2171                                         TLinearFitter *fitterT = GetTiltedRiemanFitter();
2172                                         cstreamer << "MakeSeeds2"
2173                                                 << "EventNumber="               << eventNumber
2174                                                 << "CandidateNumber="   << candidateNumber
2175                                                 << "Chi2TR="                    << chi2Vals[0]
2176                                                 << "Chi2TC="                    << chi2Vals[1]
2177                                                 << "Nlayers="                   << nlayers
2178                                                 << "NUsedS="                    << nUsedCl
2179                                                 << "NUsed="                             << nusedf
2180                                                 << "Like="                              << like
2181                                                 << "S0.="                               << &cseed[0]
2182                                                 << "S1.="                               << &cseed[1]
2183                                                 << "S2.="                               << &cseed[2]
2184                                                 << "S3.="                               << &cseed[3]
2185                                                 << "S4.="                               << &cseed[4]
2186                                                 << "S5.="                               << &cseed[5]
2187                                                 << "Label="                             << label
2188                                                 << "Freq="                              << frequency
2189                                                 << "FitterT.="                  << fitterT
2190                                                 << "FitterTC.="                 << fitterTC
2191                                                 << "\n";
2192                                 }
2193
2194                                 ntracks++;
2195                                 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2196                                 if(ntracks == kMaxTracksStack){
2197                                         AliWarning(Form("Number of seeds reached maximum allowed (%d) in stack.", kMaxTracksStack));
2198                                         for(int isl=0; isl<4; isl++) delete layer[isl];
2199                                         return ntracks;
2200                                 }
2201                                 cseed += 6;
2202                         }
2203                 }
2204         }
2205         for(int isl=0; isl<4; isl++) delete layer[isl];
2206
2207         return ntracks;
2208 }
2209
2210 //_____________________________________________________________________________
2211 AliTRDtrackV1* AliTRDtrackerV1::MakeTrack(AliTRDseedV1 *seeds, Double_t *params)
2212 {
2213   //
2214   // Build a TRD track out of tracklet candidates
2215   //
2216   // Parameters :
2217   //   seeds  : array of tracklets
2218   //   params : track parameters (see MakeSeeds() function body for a detailed description)
2219   //
2220   // Output :
2221   //   The TRD track.
2222   //
2223   // Detailed description
2224   //
2225   // To be discussed with Marian !!
2226   //
2227
2228   Double_t alpha = AliTRDgeometry::GetAlpha();
2229   Double_t shift = AliTRDgeometry::GetAlpha()/2.0;
2230   Double_t c[15];
2231
2232   c[ 0] = 0.2;
2233   c[ 1] = 0.0; c[ 2] = 2.0;
2234   c[ 3] = 0.0; c[ 4] = 0.0; c[ 5] = 0.02;
2235   c[ 6] = 0.0; c[ 7] = 0.0; c[ 8] = 0.0;  c[ 9] = 0.1;
2236   c[10] = 0.0; c[11] = 0.0; c[12] = 0.0;  c[13] = 0.0; c[14] = params[5]*params[5]*0.01;
2237
2238   AliTRDtrackV1 *track = new AliTRDtrackV1(seeds, &params[1], c, params[0], params[6]*alpha+shift);
2239         track->PropagateTo(params[0]-5.0);
2240   track->ResetCovariance(1);
2241   Int_t nc = FollowBackProlongation(*track);
2242         //AliInfo(Form("N clusters for track %d", nc));
2243         if (nc < 30) {
2244     delete track;
2245     track = 0x0;
2246   } else {
2247      track->CookdEdx();
2248      track->CookdEdxTimBin(-1);
2249      track->CookLabel(.9);
2250   }
2251
2252   return track;
2253 }
2254
2255
2256 //____________________________________________________________________
2257 Int_t AliTRDtrackerV1::ImproveSeedQuality(AliTRDtrackingChamber **stack, AliTRDseedV1 *cseed)
2258 {
2259   //
2260   // Sort tracklets according to "quality" and try to "improve" the first 4 worst
2261   //
2262   // Parameters :
2263   //  layers : Array of propagation layers for a stack/supermodule
2264   //  cseed  : Array of 6 seeding tracklets which has to be improved
2265   //
2266   // Output :
2267   //   cssed : Improved seeds
2268   //
2269   // Detailed description
2270   //
2271   // Iterative procedure in which new clusters are searched for each
2272   // tracklet seed such that the seed quality (see AliTRDseed::GetQuality())
2273   // can be maximized. If some optimization is found the old seeds are replaced.
2274   //
2275         // debug level: 7
2276         //
2277
2278         // make a local working copy
2279         AliTRDtrackingChamber *chamber = 0x0;
2280         AliTRDseedV1 bseed[6];
2281         Int_t nLayers = 0;
2282         for (Int_t jLayer = 0; jLayer < 6; jLayer++) bseed[jLayer] = cseed[jLayer];
2283
2284         Float_t lastquality = 10000.0;
2285         Float_t lastchi2    = 10000.0;
2286         Float_t chi2        =  1000.0;
2287
2288         for (Int_t iter = 0; iter < 4; iter++) {
2289                 Float_t sumquality = 0.0;
2290                 Float_t squality[6];
2291                 Int_t   sortindexes[6];
2292
2293                 for (Int_t jLayer = 0; jLayer < 6; jLayer++) {
2294                         squality[jLayer]  = bseed[jLayer].IsOK() ? bseed[jLayer].GetQuality(kTRUE) : -1.;
2295                         sumquality += squality[jLayer];
2296                 }
2297                 if ((sumquality >= lastquality) || (chi2       >     lastchi2)) break;
2298
2299                 nLayers = 0;
2300                 lastquality = sumquality;
2301                 lastchi2    = chi2;
2302                 if (iter > 0) for (Int_t jLayer = 0; jLayer < 6; jLayer++) cseed[jLayer] = bseed[jLayer];
2303
2304                 TMath::Sort(6, squality, sortindexes, kFALSE);
2305                 for (Int_t jLayer = 5; jLayer > 1; jLayer--) {
2306                         Int_t bLayer = sortindexes[jLayer];
2307                         if(!(chamber = stack[bLayer])) continue;
2308                         bseed[bLayer].AttachClustersIter(chamber, squality[bLayer], kTRUE);
2309                         if(bseed[bLayer].IsOK()) nLayers++;
2310                 }
2311
2312                 chi2 = FitTiltedRieman(bseed, kTRUE);
2313                 if(AliTRDReconstructor::StreamLevel() >= 7){
2314                         Int_t eventNumber               = AliTRDtrackerDebug::GetEventNumber();
2315                         Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2316                         TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
2317                         TTreeSRedirector &cstreamer = *fgDebugStreamer;
2318                         cstreamer << "ImproveSeedQuality"
2319                         << "EventNumber="               << eventNumber
2320                         << "CandidateNumber="   << candidateNumber
2321                         << "Iteration="                         << iter
2322                         << "S0.="                                                       << &bseed[0]
2323                         << "S1.="                                                       << &bseed[1]
2324                         << "S2.="                                                       << &bseed[2]
2325                         << "S3.="                                                       << &bseed[3]
2326                         << "S4.="                                                       << &bseed[4]
2327                         << "S5.="                                                       << &bseed[5]
2328                         << "FitterT.="                          << tiltedRieman
2329                         << "\n";
2330                 }
2331         } // Loop: iter
2332
2333         // we are sure that at least 2 tracklets are OK !
2334         return nLayers+2;
2335 }
2336
2337 //_________________________________________________________________________
2338 Double_t AliTRDtrackerV1::CalculateTrackLikelihood(AliTRDseedV1 *tracklets, Double_t *chi2){
2339 //
2340 // Calculates the Track Likelihood value. This parameter serves as main quality criterion for
2341 // the track selection
2342 // The likelihood value containes:
2343 //    - The chi2 values from the both fitters and the chi2 values in z-direction from a linear fit
2344 //    - The Sum of the Parameter  |slope_ref - slope_fit|/Sigma of the tracklets
2345 // For all Parameters an exponential dependency is used
2346 //
2347 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
2348 //             - Array of chi2 values:
2349 //                 * Non-Constrained Tilted Riemann fit
2350 //                 * Vertex-Constrained Tilted Riemann fit
2351 //                 * z-Direction from Linear fit
2352 // Output:     - The calculated track likelihood
2353 //
2354 // debug level 2
2355 //
2356
2357         Double_t sumdaf = 0, nLayers = 0;
2358         for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
2359                 if(!tracklets[iLayer].IsOK()) continue;
2360                 sumdaf += TMath::Abs((tracklets[iLayer].GetYfit(1) - tracklets[iLayer].GetYref(1))/ tracklets[iLayer].GetSigmaY2());
2361                 nLayers++;
2362         }
2363         sumdaf /= Float_t (nLayers - 2.0);
2364
2365         Double_t likeChi2Z  = TMath::Exp(-chi2[2] * 0.14);                      // Chi2Z
2366         Double_t likeChi2TC = TMath::Exp(-chi2[1] * 0.677);                     // Constrained Tilted Riemann
2367         Double_t likeChi2TR = TMath::Exp(-chi2[0] * 0.78);                      // Non-constrained Tilted Riemann
2368         Double_t likeAF     = TMath::Exp(-sumdaf * 3.23);
2369         Double_t trackLikelihood     = likeChi2Z * likeChi2TR * likeAF;
2370
2371         if(AliTRDReconstructor::StreamLevel() >= 2){
2372                 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2373                 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2374                 TTreeSRedirector &cstreamer = *fgDebugStreamer;
2375                 cstreamer << "CalculateTrackLikelihood0"
2376                         << "EventNumber="                       << eventNumber
2377                         << "CandidateNumber="   << candidateNumber
2378                         << "LikeChi2Z="                         << likeChi2Z
2379                         << "LikeChi2TR="                        << likeChi2TR
2380                         << "LikeChi2TC="                        << likeChi2TC
2381                         << "LikeAF="                                    << likeAF
2382                         << "TrackLikelihood=" << trackLikelihood
2383                         << "\n";
2384         }
2385
2386         return trackLikelihood;
2387 }
2388
2389 //____________________________________________________________________
2390 Double_t AliTRDtrackerV1::CookLikelihood(AliTRDseedV1 *cseed, Int_t planes[4]
2391                                        , Double_t *chi2)
2392 {
2393   //
2394   // Calculate the probability of this track candidate.
2395   //
2396   // Parameters :
2397   //   cseeds : array of candidate tracklets
2398   //   planes : array of seeding planes (see seeding configuration)
2399   //   chi2   : chi2 values (on the Z and Y direction) from the rieman fit of the track.
2400   //
2401   // Output :
2402   //   likelihood value
2403   //
2404   // Detailed description
2405   //
2406   // The track quality is estimated based on the following 4 criteria:
2407   //  1. precision of the rieman fit on the Y direction (likea)
2408   //  2. chi2 on the Y direction (likechi2y)
2409   //  3. chi2 on the Z direction (likechi2z)
2410   //  4. number of attached clusters compared to a reference value
2411   //     (see AliTRDrecoParam::fkFindable) (likeN)
2412   //
2413   // The distributions for each type of probabilities are given below as of
2414   // (date). They have to be checked to assure consistency of estimation.
2415   //
2416
2417         // ratio of the total number of clusters/track which are expected to be found by the tracker.
2418         Float_t fgFindable = AliTRDReconstructor::RecoParam()->GetFindableClusters();
2419
2420
2421         Int_t nclusters = 0;
2422         Double_t sumda = 0.;
2423         for(UChar_t ilayer = 0; ilayer < 4; ilayer++){
2424                 Int_t jlayer = planes[ilayer];
2425                 nclusters += cseed[jlayer].GetN2();
2426                 sumda += TMath::Abs(cseed[jlayer].GetYfitR(1) - cseed[jlayer].GetYref(1));
2427         }
2428         Double_t likea     = TMath::Exp(-sumda*10.6);
2429         Double_t likechi2y  = 0.0000000001;
2430         if (chi2[0] < 0.5) likechi2y += TMath::Exp(-TMath::Sqrt(chi2[0]) * 7.73);
2431         Double_t likechi2z = TMath::Exp(-chi2[1] * 0.088) / TMath::Exp(-chi2[1] * 0.019);
2432         Int_t enc = Int_t(fgFindable*4.*fgNTimeBins);   // Expected Number Of Clusters, normally 72
2433         Double_t likeN     = TMath::Exp(-(enc - nclusters) * 0.19);
2434
2435         Double_t like      = likea * likechi2y * likechi2z * likeN;
2436
2437 //      AliInfo(Form("sumda(%f) chi2[0](%f) chi2[1](%f) likea(%f) likechi2y(%f) likechi2z(%f) nclusters(%d) likeN(%f)", sumda, chi2[0], chi2[1], likea, likechi2y, likechi2z, nclusters, likeN));
2438         if(AliTRDReconstructor::StreamLevel() >= 2){
2439                 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2440                 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2441                 // The Debug Stream contains the seed
2442                 TTreeSRedirector &cstreamer = *fgDebugStreamer;
2443                 cstreamer << "CookLikelihood"
2444                         << "EventNumber="                       << eventNumber
2445                         << "CandidateNumber=" << candidateNumber
2446                         << "tracklet0.="                        << &cseed[0]
2447                         << "tracklet1.="                        << &cseed[1]
2448                         << "tracklet2.="                        << &cseed[2]
2449                         << "tracklet3.="                        << &cseed[3]
2450                         << "tracklet4.="                        << &cseed[4]
2451                         << "tracklet5.="                        << &cseed[5]
2452                         << "sumda="                                             << sumda
2453                         << "chi0="                                              << chi2[0]
2454                         << "chi1="                                              << chi2[1]
2455                         << "likea="                                             << likea
2456                         << "likechi2y="                         << likechi2y
2457                         << "likechi2z="                         << likechi2z
2458                         << "nclusters="                         << nclusters
2459                         << "likeN="                                             << likeN
2460                         << "like="                                              << like
2461                         << "\n";
2462         }
2463
2464         return like;
2465 }
2466
2467
2468
2469 //____________________________________________________________________
2470 void AliTRDtrackerV1::GetSeedingConfig(Int_t iconfig, Int_t planes[4])
2471 {
2472   //
2473   // Map seeding configurations to detector planes.
2474   //
2475   // Parameters :
2476   //   iconfig : configuration index
2477   //   planes  : member planes of this configuration. On input empty.
2478   //
2479   // Output :
2480   //   planes : contains the planes which are defining the configuration
2481   //
2482   // Detailed description
2483   //
2484   // Here is the list of seeding planes configurations together with
2485   // their topological classification:
2486   //
2487   //  0 - 5432 TQ 0
2488   //  1 - 4321 TQ 0
2489   //  2 - 3210 TQ 0
2490   //  3 - 5321 TQ 1
2491   //  4 - 4210 TQ 1
2492   //  5 - 5431 TQ 1
2493   //  6 - 4320 TQ 1
2494   //  7 - 5430 TQ 2
2495   //  8 - 5210 TQ 2
2496   //  9 - 5421 TQ 3
2497   // 10 - 4310 TQ 3
2498   // 11 - 5410 TQ 4
2499   // 12 - 5420 TQ 5
2500   // 13 - 5320 TQ 5
2501   // 14 - 5310 TQ 5
2502   //
2503   // The topologic quality is modeled as follows:
2504   // 1. The general model is define by the equation:
2505   //  p(conf) = exp(-conf/2)
2506   // 2. According to the topologic classification, configurations from the same
2507   //    class are assigned the agerage value over the model values.
2508   // 3. Quality values are normalized.
2509   //
2510   // The topologic quality distribution as function of configuration is given below:
2511   //Begin_Html
2512   // <img src="gif/topologicQA.gif">
2513   //End_Html
2514   //
2515
2516         switch(iconfig){
2517         case 0: // 5432 TQ 0
2518                 planes[0] = 2;
2519                 planes[1] = 3;
2520                 planes[2] = 4;
2521                 planes[3] = 5;
2522                 break;
2523         case 1: // 4321 TQ 0
2524                 planes[0] = 1;
2525                 planes[1] = 2;
2526                 planes[2] = 3;
2527                 planes[3] = 4;
2528                 break;
2529         case 2: // 3210 TQ 0
2530                 planes[0] = 0;
2531                 planes[1] = 1;
2532                 planes[2] = 2;
2533                 planes[3] = 3;
2534                 break;
2535         case 3: // 5321 TQ 1
2536                 planes[0] = 1;
2537                 planes[1] = 2;
2538                 planes[2] = 3;
2539                 planes[3] = 5;
2540                 break;
2541         case 4: // 4210 TQ 1
2542                 planes[0] = 0;
2543                 planes[1] = 1;
2544                 planes[2] = 2;
2545                 planes[3] = 4;
2546                 break;
2547         case 5: // 5431 TQ 1
2548                 planes[0] = 1;
2549                 planes[1] = 3;
2550                 planes[2] = 4;
2551                 planes[3] = 5;
2552                 break;
2553         case 6: // 4320 TQ 1
2554                 planes[0] = 0;
2555                 planes[1] = 2;
2556                 planes[2] = 3;
2557                 planes[3] = 4;
2558                 break;
2559         case 7: // 5430 TQ 2
2560                 planes[0] = 0;
2561                 planes[1] = 3;
2562                 planes[2] = 4;
2563                 planes[3] = 5;
2564                 break;
2565         case 8: // 5210 TQ 2
2566                 planes[0] = 0;
2567                 planes[1] = 1;
2568                 planes[2] = 2;
2569                 planes[3] = 5;
2570                 break;
2571         case 9: // 5421 TQ 3
2572                 planes[0] = 1;
2573                 planes[1] = 2;
2574                 planes[2] = 4;
2575                 planes[3] = 5;
2576                 break;
2577         case 10: // 4310 TQ 3
2578                 planes[0] = 0;
2579                 planes[1] = 1;
2580                 planes[2] = 3;
2581                 planes[3] = 4;
2582                 break;
2583         case 11: // 5410 TQ 4
2584                 planes[0] = 0;
2585                 planes[1] = 1;
2586                 planes[2] = 4;
2587                 planes[3] = 5;
2588                 break;
2589         case 12: // 5420 TQ 5
2590                 planes[0] = 0;
2591                 planes[1] = 2;
2592                 planes[2] = 4;
2593                 planes[3] = 5;
2594                 break;
2595         case 13: // 5320 TQ 5
2596                 planes[0] = 0;
2597                 planes[1] = 2;
2598                 planes[2] = 3;
2599                 planes[3] = 5;
2600                 break;
2601         case 14: // 5310 TQ 5
2602                 planes[0] = 0;
2603                 planes[1] = 1;
2604                 planes[2] = 3;
2605                 planes[3] = 5;
2606                 break;
2607         }
2608 }
2609
2610 //____________________________________________________________________
2611 void AliTRDtrackerV1::GetExtrapolationConfig(Int_t iconfig, Int_t planes[2])
2612 {
2613   //
2614   // Returns the extrapolation planes for a seeding configuration.
2615   //
2616   // Parameters :
2617   //   iconfig : configuration index
2618   //   planes  : planes which are not in this configuration. On input empty.
2619   //
2620   // Output :
2621   //   planes : contains the planes which are not in the configuration
2622   //
2623   // Detailed description
2624   //
2625
2626         switch(iconfig){
2627         case 0: // 5432 TQ 0
2628                 planes[0] = 1;
2629                 planes[1] = 0;
2630                 break;
2631         case 1: // 4321 TQ 0
2632                 planes[0] = 5;
2633                 planes[1] = 0;
2634                 break;
2635         case 2: // 3210 TQ 0
2636                 planes[0] = 4;
2637                 planes[1] = 5;
2638                 break;
2639         case 3: // 5321 TQ 1
2640                 planes[0] = 4;
2641                 planes[1] = 0;
2642                 break;
2643         case 4: // 4210 TQ 1
2644                 planes[0] = 5;
2645                 planes[1] = 3;
2646                 break;
2647         case 5: // 5431 TQ 1
2648                 planes[0] = 2;
2649                 planes[1] = 0;
2650                 break;
2651         case 6: // 4320 TQ 1
2652                 planes[0] = 5;
2653                 planes[1] = 1;
2654                 break;
2655         case 7: // 5430 TQ 2
2656                 planes[0] = 2;
2657                 planes[1] = 1;
2658                 break;
2659         case 8: // 5210 TQ 2
2660                 planes[0] = 4;
2661                 planes[1] = 3;
2662                 break;
2663         case 9: // 5421 TQ 3
2664                 planes[0] = 3;
2665                 planes[1] = 0;
2666                 break;
2667         case 10: // 4310 TQ 3
2668                 planes[0] = 5;
2669                 planes[1] = 2;
2670                 break;
2671         case 11: // 5410 TQ 4
2672                 planes[0] = 3;
2673                 planes[1] = 2;
2674                 break;
2675         case 12: // 5420 TQ 5
2676                 planes[0] = 3;
2677                 planes[1] = 1;
2678                 break;
2679         case 13: // 5320 TQ 5
2680                 planes[0] = 4;
2681                 planes[1] = 1;
2682                 break;
2683         case 14: // 5310 TQ 5
2684                 planes[0] = 4;
2685                 planes[1] = 2;
2686                 break;
2687         }
2688 }
2689
2690 //____________________________________________________________________
2691 AliCluster* AliTRDtrackerV1::GetCluster(Int_t idx) const
2692 {
2693         Int_t ncls = fClusters->GetEntriesFast();
2694         return idx >= 0 || idx < ncls ? (AliCluster*)fClusters->UncheckedAt(idx) : 0x0;
2695 }
2696
2697 //____________________________________________________________________
2698 Float_t AliTRDtrackerV1::CalculateReferenceX(AliTRDseedV1 *tracklets){
2699 //
2700 // Calculates the reference x-position for the tilted Rieman fit defined as middle
2701 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
2702 // are taken into account
2703 //
2704 // Parameters:  - Array of tracklets(AliTRDseedV1)
2705 //
2706 // Output:              - The reference x-position(Float_t)
2707 //
2708         Int_t nDistances = 0;
2709         Float_t meanDistance = 0.;
2710         Int_t startIndex = 5;
2711         for(Int_t il =5; il > 0; il--){
2712                 if(tracklets[il].IsOK() && tracklets[il -1].IsOK()){
2713                         Float_t xdiff = tracklets[il].GetX0() - tracklets[il -1].GetX0();
2714                         meanDistance += xdiff;
2715                         nDistances++;
2716                 }
2717                 if(tracklets[il].IsOK()) startIndex = il;
2718         }
2719         if(tracklets[0].IsOK()) startIndex = 0;
2720         if(!nDistances){
2721                 // We should normally never get here
2722                 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
2723                 Int_t iok = 0, idiff = 0;
2724                 // This attempt is worse and should be avoided:
2725                 // check for two chambers which are OK and repeat this without taking the mean value
2726                 // Strategy avoids a division by 0;
2727                 for(Int_t il = 5; il >= 0; il--){
2728                         if(tracklets[il].IsOK()){
2729                                 xpos[iok] = tracklets[il].GetX0();
2730                                 iok++;
2731                                 startIndex = il;
2732                         }
2733                         if(iok) idiff++;        // to get the right difference;
2734                         if(iok > 1) break;
2735                 }
2736                 if(iok > 1){
2737                         meanDistance = (xpos[0] - xpos[1])/idiff;
2738                 }
2739                 else{
2740                         // we have do not even have 2 layers which are OK? The we do not need to fit at all
2741                         return 331.;
2742                 }
2743         }
2744         else{
2745                 meanDistance /= nDistances;
2746         }
2747         return tracklets[startIndex].GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
2748 }
2749
2750 //_____________________________________________________________________________
2751 Int_t AliTRDtrackerV1::Freq(Int_t n, const Int_t *inlist
2752                         , Int_t *outlist, Bool_t down)
2753 {
2754   //
2755   // Sort eleements according occurancy
2756   // The size of output array has is 2*n
2757   //
2758
2759   if (n <= 0) {
2760     return 0;
2761   }
2762
2763   Int_t *sindexS = new Int_t[n];   // Temporary array for sorting
2764   Int_t *sindexF = new Int_t[2*n];
2765   for (Int_t i = 0; i < n; i++) {
2766     sindexF[i] = 0;
2767   }
2768
2769   TMath::Sort(n,inlist,sindexS,down);
2770
2771   Int_t last     = inlist[sindexS[0]];
2772   Int_t val      = last;
2773   sindexF[0]     = 1;
2774   sindexF[0+n]   = last;
2775   Int_t countPos = 0;
2776
2777   // Find frequency
2778   for (Int_t i = 1; i < n; i++) {
2779     val = inlist[sindexS[i]];
2780     if (last == val) {
2781       sindexF[countPos]++;
2782     }
2783     else {
2784       countPos++;
2785       sindexF[countPos+n] = val;
2786       sindexF[countPos]++;
2787       last                = val;
2788     }
2789   }
2790   if (last == val) {
2791     countPos++;
2792   }
2793
2794   // Sort according frequency
2795   TMath::Sort(countPos,sindexF,sindexS,kTRUE);
2796
2797   for (Int_t i = 0; i < countPos; i++) {
2798     outlist[2*i  ] = sindexF[sindexS[i]+n];
2799     outlist[2*i+1] = sindexF[sindexS[i]];
2800   }
2801
2802   delete [] sindexS;
2803   delete [] sindexF;
2804
2805   return countPos;
2806
2807 }
2808
2809 //_____________________________________________________________________________
2810 Float_t AliTRDtrackerV1::GetChi2Y(AliTRDseedV1 *tracklets) const
2811 {
2812 //      Chi2 definition on y-direction
2813
2814         Float_t chi2 = 0;
2815         for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
2816                 if(!tracklets[ipl].IsOK()) continue;
2817                 Double_t distLayer = tracklets[ipl].GetYfit(0) - tracklets[ipl].GetYref(0);
2818                 chi2 += distLayer * distLayer;
2819         }
2820         return chi2;
2821 }
2822
2823 //_____________________________________________________________________________
2824 Float_t AliTRDtrackerV1::GetChi2Z(AliTRDseedV1 *tracklets) const
2825 {
2826 //      Chi2 definition on z-direction
2827
2828         Float_t chi2 = 0;
2829         for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
2830                 if(!tracklets[ipl].IsOK()) continue;
2831                 Double_t distLayer = tracklets[ipl].GetMeanz() - tracklets[ipl].GetZref(0);
2832                 chi2 += distLayer * distLayer;
2833         }
2834         return chi2;
2835 }