1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 ///////////////////////////////////////////////////////////////////////////////
23 // Alex Bercuci <A.Bercuci@gsi.de> //
24 // Markus Fasel <M.Fasel@gsi.de> //
26 ///////////////////////////////////////////////////////////////////////////////
29 #include <TDirectory.h>
30 #include <TLinearFitter.h>
32 #include <TClonesArray.h>
33 #include <TTreeStream.h>
34 #include <TGeoMatrix.h>
35 #include <TGeoManager.h>
38 #include "AliMathBase.h"
39 #include "AliESDEvent.h"
40 #include "AliGeomManager.h"
41 #include "AliRieman.h"
42 #include "AliTrackPointArray.h"
44 #include "AliTRDgeometry.h"
45 #include "AliTRDpadPlane.h"
46 #include "AliTRDcalibDB.h"
47 #include "AliTRDReconstructor.h"
48 #include "AliTRDCalibraFillHisto.h"
49 #include "AliTRDrecoParam.h"
51 #include "AliTRDcluster.h"
52 #include "AliTRDdigitsParam.h"
53 #include "AliTRDseedV1.h"
54 #include "AliTRDtrackV1.h"
55 #include "AliTRDtrackerV1.h"
56 #include "AliTRDtrackerDebug.h"
57 #include "AliTRDtrackingChamber.h"
58 #include "AliTRDchamberTimeBin.h"
60 ClassImp(AliTRDtrackerV1)
61 ClassImp(AliTRDtrackerV1::AliTRDLeastSquare)
62 ClassImp(AliTRDtrackerV1::AliTRDtrackFitterRieman)
64 const Float_t AliTRDtrackerV1::fgkMinClustersInTrack = 0.5; //
65 const Float_t AliTRDtrackerV1::fgkLabelFraction = 0.8; //
66 const Double_t AliTRDtrackerV1::fgkMaxChi2 = 12.0; //
67 const Double_t AliTRDtrackerV1::fgkMaxSnp = 0.95; // Maximum local sine of the azimuthal angle
68 const Double_t AliTRDtrackerV1::fgkMaxStep = 2.0; // Maximal step size in propagation
69 Double_t AliTRDtrackerV1::fgTopologicQA[kNConfigs] = {
70 0.5112, 0.5112, 0.5112, 0.0786, 0.0786,
71 0.0786, 0.0786, 0.0579, 0.0579, 0.0474,
72 0.0474, 0.0408, 0.0335, 0.0335, 0.0335
74 const Double_t AliTRDtrackerV1::fgkX0[kNPlanes] = {
75 300.2, 312.8, 325.4, 338.0, 350.6, 363.2};
76 Int_t AliTRDtrackerV1::fgNTimeBins = 0;
77 AliRieman* AliTRDtrackerV1::fgRieman = NULL;
78 TLinearFitter* AliTRDtrackerV1::fgTiltedRieman = NULL;
79 TLinearFitter* AliTRDtrackerV1::fgTiltedRiemanConstrained = NULL;
81 //____________________________________________________________________
82 AliTRDtrackerV1::AliTRDtrackerV1(AliTRDReconstructor *rec)
84 ,fkReconstructor(NULL)
94 // Default constructor.
97 SetReconstructor(rec); // initialize reconstructor
99 // initialize geometry
100 if(!AliGeomManager::GetGeometry()){
101 AliFatal("Could not get geometry.");
103 fGeom = new AliTRDgeometry();
104 fGeom->CreateClusterMatrixArray();
105 TGeoHMatrix *matrix = NULL;
106 Double_t loc[] = {0., 0., 0.};
107 Double_t glb[] = {0., 0., 0.};
108 for(Int_t ily=kNPlanes; ily--;){
110 while(!(matrix = fGeom->GetClusterMatrix(AliTRDgeometry::GetDetector(ily, 2, ism)))) ism++;
112 AliError(Form("Could not get transformation matrix for layer %d. Use default.", ily));
113 fR[ily] = fgkX0[ily];
116 matrix->LocalToMaster(loc, glb);
117 fR[ily] = glb[0]+ AliTRDgeometry::AnodePos()-.5*AliTRDgeometry::AmThick() - AliTRDgeometry::DrThick();
120 // initialize cluster containers
121 for (Int_t isector = 0; isector < AliTRDgeometry::kNsector; isector++) new(&fTrSec[isector]) AliTRDtrackingSector(fGeom, isector);
124 memset(fTrackQuality, 0, kMaxTracksStack*sizeof(Double_t));
125 memset(fSeedLayer, 0, kMaxTracksStack*sizeof(Int_t));
126 memset(fSeedTB, 0, kNSeedPlanes*sizeof(AliTRDchamberTimeBin*));
127 fTracksESD = new TClonesArray("AliESDtrack", 2*kMaxTracksStack);
128 fTracksESD->SetOwner();
131 //____________________________________________________________________
132 AliTRDtrackerV1::~AliTRDtrackerV1()
138 if(fgRieman) delete fgRieman; fgRieman = NULL;
139 if(fgTiltedRieman) delete fgTiltedRieman; fgTiltedRieman = NULL;
140 if(fgTiltedRiemanConstrained) delete fgTiltedRiemanConstrained; fgTiltedRiemanConstrained = NULL;
141 for(Int_t isl =0; isl<kNSeedPlanes; isl++) if(fSeedTB[isl]) delete fSeedTB[isl];
142 if(fTracksESD){ fTracksESD->Delete(); delete fTracksESD; }
143 if(fTracks) {fTracks->Delete(); delete fTracks;}
144 if(fTracklets) {fTracklets->Delete(); delete fTracklets;}
146 fClusters->Delete(); delete fClusters;
148 if(fGeom) delete fGeom;
151 //____________________________________________________________________
152 Int_t AliTRDtrackerV1::Clusters2Tracks(AliESDEvent *esd)
155 // Steering stand alone tracking for full TRD detector
158 // esd : The ESD event. On output it contains
159 // the ESD tracks found in TRD.
162 // Number of tracks found in the TRD detector.
164 // Detailed description
165 // 1. Launch individual SM trackers.
166 // See AliTRDtrackerV1::Clusters2TracksSM() for details.
170 AliError("Reconstruction configuration not initialized. Call first AliTRDReconstructor::SetRecoParam().");
174 //AliInfo("Start Track Finder ...");
176 for(int ism=0; ism<AliTRDgeometry::kNsector; ism++){
177 // for(int ism=1; ism<2; ism++){
178 //AliInfo(Form("Processing supermodule %i ...", ism));
179 ntracks += Clusters2TracksSM(ism, esd);
181 AliInfo(Form("Number of tracks: !TRDin[%d]", ntracks));
186 //_____________________________________________________________________________
187 Bool_t AliTRDtrackerV1::GetTrackPoint(Int_t index, AliTrackPoint &p) const
189 //AliInfo(Form("Asking for tracklet %d", index));
191 // reset position of the point before using it
192 p.SetXYZ(0., 0., 0.);
193 AliTRDseedV1 *tracklet = GetTracklet(index);
194 if (!tracklet) return kFALSE;
196 // get detector for this tracklet
197 Int_t det = tracklet->GetDetector();
198 Int_t sec = fGeom->GetSector(det);
199 Double_t alpha = (sec+.5)*AliTRDgeometry::GetAlpha(),
200 sinA = TMath::Sin(alpha),
201 cosA = TMath::Cos(alpha);
203 local[0] = tracklet->GetX();
204 local[1] = tracklet->GetY();
205 local[2] = tracklet->GetZ();
207 fGeom->RotateBack(det, local, global);
209 Double_t cov2D[3]; Float_t cov[6];
210 tracklet->GetCovAt(local[0], cov2D);
211 cov[0] = cov2D[0]*sinA*sinA;
212 cov[1] =-cov2D[0]*sinA*cosA;
213 cov[2] =-cov2D[1]*sinA;
214 cov[3] = cov2D[0]*cosA*cosA;
215 cov[4] = cov2D[1]*cosA;
217 // store the global position of the tracklet and its covariance matrix in the track point
218 p.SetXYZ(global[0],global[1],global[2], cov);
221 AliGeomManager::ELayerID iLayer = AliGeomManager::ELayerID(AliGeomManager::kTRD1+fGeom->GetLayer(det));
222 Int_t modId = fGeom->GetSector(det) * AliTRDgeometry::kNstack + fGeom->GetStack(det);
223 UShort_t volid = AliGeomManager::LayerToVolUID(iLayer, modId);
224 p.SetVolumeID(volid);
229 //____________________________________________________________________
230 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitter()
232 if(!fgTiltedRieman) fgTiltedRieman = new TLinearFitter(4, "hyp4");
233 return fgTiltedRieman;
236 //____________________________________________________________________
237 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitterConstraint()
239 if(!fgTiltedRiemanConstrained) fgTiltedRiemanConstrained = new TLinearFitter(2, "hyp2");
240 return fgTiltedRiemanConstrained;
243 //____________________________________________________________________
244 AliRieman* AliTRDtrackerV1::GetRiemanFitter()
246 if(!fgRieman) fgRieman = new AliRieman(AliTRDseedV1::kNtb * AliTRDgeometry::kNlayer);
250 //_____________________________________________________________________________
251 Int_t AliTRDtrackerV1::PropagateBack(AliESDEvent *event)
253 // Propagation of ESD tracks from TPC to TOF detectors and building of the TRD track. For building
254 // a TRD track an ESD track is used as seed. The informations obtained on the TRD track (measured points,
255 // covariance, PID, etc.) are than used to update the corresponding ESD track.
256 // Each track seed is first propagated to the geometrical limit of the TRD detector.
257 // Its prolongation is searched in the TRD and if corresponding clusters are found tracklets are
258 // constructed out of them (see AliTRDseedV1::AttachClusters()) and the track is updated.
259 // Otherwise the ESD track is left unchanged.
261 // The following steps are performed:
262 // 1. Selection of tracks based on the variance in the y-z plane.
263 // 2. Propagation to the geometrical limit of the TRD volume. If track propagation fails the AliESDtrack::kTRDStop is set.
264 // 3. Prolongation inside the fiducial volume (see AliTRDtrackerV1::FollowBackProlongation()) and marking
265 // the following status bits:
266 // - AliESDtrack::kTRDin - if the tracks enters the TRD fiducial volume
267 // - AliESDtrack::kTRDStop - if the tracks fails propagation
268 // - AliESDtrack::kTRDbackup - if the tracks fulfills chi2 conditions and qualify for refitting
269 // 4. Writting to friends, PID, MC label, quality etc. Setting status bit AliESDtrack::kTRDout.
270 // 5. Propagation to TOF. If track propagation fails the AliESDtrack::kTRDStop is set.
273 if(!fClusters || !fClusters->GetEntriesFast()){
274 AliInfo("No TRD clusters");
277 AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance(); // Calibration monitor
278 if (!calibra) AliInfo("Could not get Calibra instance");
279 if (!fgNTimeBins) fgNTimeBins = fkReconstructor->GetNTimeBins();
282 Int_t nFound = 0, // number of tracks found
283 nBacked = 0, // number of tracks backed up for refit
284 nSeeds = 0, // total number of ESD seeds
285 nTRDseeds= 0, // number of seeds in the TRD acceptance
286 nTPCseeds= 0; // number of TPC seeds
287 Float_t foundMin = 20.0;
289 Float_t *quality = NULL;
291 nSeeds = event->GetNumberOfTracks();
292 // Sort tracks according to quality
293 // (covariance in the yz plane)
295 quality = new Float_t[nSeeds];
296 index = new Int_t[nSeeds];
297 for (Int_t iSeed = nSeeds; iSeed--;) {
298 AliESDtrack *seed = event->GetTrack(iSeed);
299 Double_t covariance[15];
300 seed->GetExternalCovariance(covariance);
301 quality[iSeed] = covariance[0] + covariance[2];
303 TMath::Sort(nSeeds, quality, index,kFALSE);
306 // Propagate all seeds
309 for (Int_t iSeed = 0; iSeed < nSeeds; iSeed++) {
311 // Get the seeds in sorted sequence
312 AliESDtrack *seed = event->GetTrack(index[iSeed]);
313 Float_t p4 = seed->GetC(seed->GetBz());
315 // Check the seed status
316 ULong_t status = seed->GetStatus();
317 if ((status & AliESDtrack::kTPCout) == 0) continue;
318 if ((status & AliESDtrack::kTRDout) != 0) continue;
320 // Propagate to the entrance in the TRD mother volume
321 new(&track) AliTRDtrackV1(*seed);
322 if(AliTRDgeometry::GetXtrdBeg() > (fgkMaxStep + track.GetX()) && !PropagateToX(track, AliTRDgeometry::GetXtrdBeg(), fgkMaxStep)){
323 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
326 if(!AdjustSector(&track)){
327 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
330 if(TMath::Abs(track.GetSnp()) > fgkMaxSnp) {
331 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
337 // store track status at TRD entrance
338 seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
340 // prepare track and do propagation in the TRD
341 track.SetReconstructor(fkReconstructor);
342 track.SetKink(Bool_t(seed->GetKinkIndex(0)));
343 expectedClr = FollowBackProlongation(track);
344 // check if track entered the TRD fiducial volume
345 if(track.GetTrackLow()){
346 seed->UpdateTrackParams(&track, AliESDtrack::kTRDin);
349 // check if track was stopped in the TRD
351 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
357 // computes PID for track
359 // update calibration references using this track
360 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(&track);
361 // save calibration object
362 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0 &&
363 fkRecoParam->IsOverPtThreshold(track.Pt())){
364 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(track);
365 calibTrack->SetOwner();
366 seed->AddCalibObject(calibTrack);
369 seed->UpdateTrackParams(&track, AliESDtrack::kTRDout);
370 track.UpdateESDtrack(seed);
373 if ((TMath::Abs(track.GetC(track.GetBz()) - p4) / TMath::Abs(p4) < 0.2) ||(track.Pt() > 0.8)) {
375 // Make backup for back propagation
376 Int_t foundClr = track.GetNumberOfClusters();
377 if (foundClr >= foundMin) {
378 track.CookLabel(1. - fgkLabelFraction);
379 //if(track.GetBackupTrack()) UseClusters(track.GetBackupTrack());
381 // Sign only gold tracks
382 if (track.GetChi2() / track.GetNumberOfClusters() < 4) {
383 //if ((seed->GetKinkIndex(0) == 0) && (track.Pt() < 1.5)) UseClusters(&track);
385 Bool_t isGold = kFALSE;
388 if (track.GetChi2() / track.GetNumberOfClusters() < 5) {
389 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
395 if ((!isGold) && (track.GetNCross() == 0) && (track.GetChi2() / track.GetNumberOfClusters() < 7)) {
396 //seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
397 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
402 if ((!isGold) && (track.GetBackupTrack())) {
403 if ((track.GetBackupTrack()->GetNumberOfClusters() > foundMin) && ((track.GetBackupTrack()->GetChi2()/(track.GetBackupTrack()->GetNumberOfClusters()+1)) < 7)) {
404 seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
412 // Propagation to the TOF
413 if(!(seed->GetStatus()&AliESDtrack::kTRDStop)) {
414 Int_t sm = track.GetSector();
415 // default value in case we have problems with the geometry.
416 Double_t xtof = 371.;
417 //Calculate radial position of the beginning of the TOF
418 //mother volume. In order to avoid mixing of the TRD
419 //and TOF modules some hard values are needed. This are:
420 //1. The path to the TOF module.
421 //2. The width of the TOF (29.05 cm)
422 //(with the help of Annalisa de Caro Mar-17-2009)
424 gGeoManager->cd(Form("/ALIC_1/B077_1/BSEGMO%d_1/BTOF%d_1", sm, sm));
425 TGeoHMatrix *m = NULL;
426 Double_t loc[]={0., 0., -.5*29.05}, glob[3];
428 if((m=gGeoManager->GetCurrentMatrix())){
429 m->LocalToMaster(loc, glob);
430 xtof = TMath::Sqrt(glob[0]*glob[0]+glob[1]*glob[1]);
433 if(xtof > (fgkMaxStep + track.GetX()) && !PropagateToX(track, xtof, fgkMaxStep)){
434 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
437 if(!AdjustSector(&track)){
438 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
441 if(TMath::Abs(track.GetSnp()) > fgkMaxSnp){
442 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
445 //seed->UpdateTrackParams(&track, AliESDtrack::kTRDout);
446 // TODO obsolete - delete
447 seed->SetTRDQuality(track.StatusForTOF());
449 seed->SetTRDBudget(track.GetBudget(0));
451 if(index) delete [] index;
452 if(quality) delete [] quality;
454 AliInfo(Form("Number of seeds: TPCout[%d] TRDin[%d]", nTPCseeds, nTRDseeds));
455 AliInfo(Form("Number of tracks: TRDout[%d] TRDbackup[%d]", nFound, nBacked));
457 // run stand alone tracking
458 if (fkReconstructor->IsSeeding()) Clusters2Tracks(event);
464 //____________________________________________________________________
465 Int_t AliTRDtrackerV1::RefitInward(AliESDEvent *event)
468 // Refits tracks within the TRD. The ESD event is expected to contain seeds
469 // at the outer part of the TRD.
470 // The tracks are propagated to the innermost time bin
471 // of the TRD and the ESD event is updated
472 // Origin: Thomas KUHR (Thomas.Kuhr@cern.ch)
475 Int_t nseed = 0; // contor for loaded seeds
476 Int_t found = 0; // contor for updated TRD tracks
479 if(!fClusters || !fClusters->GetEntriesFast()){
480 AliInfo("No TRD clusters");
484 for (Int_t itrack = 0; itrack < event->GetNumberOfTracks(); itrack++) {
485 AliESDtrack *seed = event->GetTrack(itrack);
486 ULong_t status = seed->GetStatus();
488 new(&track) AliTRDtrackV1(*seed);
489 if (track.GetX() < 270.0) {
490 seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
494 // reject tracks which failed propagation in the TRD or
495 // are produced by the TRD stand alone tracker
496 if(!(status & AliESDtrack::kTRDout)) continue;
497 if(!(status & AliESDtrack::kTRDin)) continue;
500 track.ResetCovariance(50.0);
502 // do the propagation and processing
503 Bool_t kUPDATE = kFALSE;
504 Double_t xTPC = 250.0;
505 if(FollowProlongation(track)){
507 if (PropagateToX(track, xTPC, fgkMaxStep)) { // -with update
508 seed->UpdateTrackParams(&track, AliESDtrack::kTRDrefit);
513 // Update the friend track
514 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0 && fkRecoParam->IsOverPtThreshold(track.Pt())){
515 TObject *o = NULL; Int_t ic = 0;
516 AliTRDtrackV1 *calibTrack = NULL;
517 while((o = seed->GetCalibObject(ic++))){
518 if(!(calibTrack = dynamic_cast<AliTRDtrackV1*>(o))) continue;
519 calibTrack->SetTrackHigh(track.GetTrackHigh());
524 // Prolongate to TPC without update
526 AliTRDtrackV1 tt(*seed);
527 if (PropagateToX(tt, xTPC, fgkMaxStep)) seed->UpdateTrackParams(&tt, AliESDtrack::kTRDbackup);
530 AliInfo(Form("Number of seeds: TRDout[%d]", nseed));
531 AliInfo(Form("Number of tracks: TRDrefit[%d]", found));
536 //____________________________________________________________________
537 Int_t AliTRDtrackerV1::FollowProlongation(AliTRDtrackV1 &t)
539 // Extrapolates the TRD track in the TPC direction.
542 // t : the TRD track which has to be extrapolated
545 // number of clusters attached to the track
547 // Detailed description
549 // Starting from current radial position of track <t> this function
550 // extrapolates the track through the 6 TRD layers. The following steps
551 // are being performed for each plane:
553 // a. get plane limits in the local x direction
554 // b. check crossing sectors
555 // c. check track inclination
556 // 2. search tracklet in the tracker list (see GetTracklet() for details)
557 // 3. evaluate material budget using the geo manager
558 // 4. propagate and update track using the tracklet information.
563 Bool_t kStoreIn = kTRUE;
564 Int_t nClustersExpected = 0;
565 for (Int_t iplane = kNPlanes; iplane--;) {
567 AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
568 AliDebug(2, Form("Tracklet[%p] ly[%d] idx[%d]", (void*)tracklet, iplane, index));
569 if(!tracklet) continue;
570 if(!tracklet->IsOK()){
571 AliDebug(1, Form("Tracklet Det[%d] !OK", tracklet->GetDetector()));
574 Double_t x = tracklet->GetX();//GetX0();
575 // reject tracklets which are not considered for inward refit
576 if(x > t.GetX()+fgkMaxStep) continue;
578 // append tracklet to track
579 t.SetTracklet(tracklet, index);
581 if (x < (t.GetX()-fgkMaxStep) && !PropagateToX(t, x+fgkMaxStep, fgkMaxStep)) break;
582 if (!AdjustSector(&t)) break;
584 // Start global position
588 // End global position
589 Double_t alpha = t.GetAlpha(), y, z;
590 if (!t.GetProlongation(x,y,z)) break;
592 xyz1[0] = x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
593 xyz1[1] = x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
596 Double_t length = TMath::Sqrt(
597 (xyz0[0]-xyz1[0])*(xyz0[0]-xyz1[0]) +
598 (xyz0[1]-xyz1[1])*(xyz0[1]-xyz1[1]) +
599 (xyz0[2]-xyz1[2])*(xyz0[2]-xyz1[2])
602 // Get material budget
604 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param)<=0.) break;
605 Double_t xrho= param[0]*param[4];
606 Double_t xx0 = param[1]; // Get mean propagation parameters
608 // Propagate and update
609 t.PropagateTo(x, xx0, xrho);
610 if (!AdjustSector(&t)) break;
617 Double_t cov[3]; tracklet->GetCovAt(x, cov);
618 Double_t p[2] = { tracklet->GetY(), tracklet->GetZ()};
619 Double_t chi2 = ((AliExternalTrackParam)t).GetPredictedChi2(p, cov);
620 if (chi2 < 1e+10 && t.Update(p, cov, chi2)){
621 nClustersExpected += tracklet->GetN();
625 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 1){
627 for(int iplane=0; iplane<AliTRDgeometry::kNlayer; iplane++){
628 AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
629 if(!tracklet) continue;
630 t.SetTracklet(tracklet, index);
633 if(fkReconstructor->IsDebugStreaming()){
634 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
635 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
636 AliTRDtrackV1 track(t);
638 cstreamer << "FollowProlongation"
639 << "EventNumber=" << eventNumber
640 << "ncl=" << nClustersExpected
641 << "track.=" << &track
645 return nClustersExpected;
649 //_____________________________________________________________________________
650 Int_t AliTRDtrackerV1::FollowBackProlongation(AliTRDtrackV1 &t)
652 // Extrapolates/Build the TRD track in the TOF direction.
655 // t : the TRD track which has to be extrapolated
658 // number of clusters attached to the track
660 // Starting from current radial position of track <t> this function
661 // extrapolates the track through the 6 TRD layers. The following steps
662 // are being performed for each plane:
663 // 1. Propagate track to the entrance of the next chamber:
664 // - get chamber limits in the radial direction
665 // - check crossing sectors
666 // - check track inclination
667 // - check track prolongation against boundary conditions (see exclusion boundaries on AliTRDgeometry::IsOnBoundary())
668 // 2. Build tracklet (see AliTRDseed::AttachClusters() for details) for this layer if needed. If only
669 // Kalman filter is needed and tracklets are already linked to the track this step is skipped.
670 // 3. Fit tracklet using the information from the Kalman filter.
671 // 4. Propagate and update track at reference radial position of the tracklet.
672 // 5. Register tracklet with the tracker and track; update pulls monitoring.
675 // 1. During the propagation a bit map is filled detailing the status of the track in each TRD chamber. The following errors are being registered for each tracklet:
676 // - AliTRDtrackV1::kProlongation : track prolongation failed
677 // - AliTRDtrackV1::kPropagation : track prolongation failed
678 // - AliTRDtrackV1::kAdjustSector : failed during sector crossing
679 // - AliTRDtrackV1::kSnp : too large bending
680 // - AliTRDtrackV1::kTrackletInit : fail to initialize tracklet
681 // - AliTRDtrackV1::kUpdate : fail to attach clusters or fit the tracklet
682 // - AliTRDtrackV1::kUnknown : anything which is not covered before
683 // 2. By default the status of the track before first TRD update is saved.
688 // Alexandru Bercuci <A.Bercuci@gsi.de>
692 Double_t driftLength = .5*AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick();
693 AliTRDtrackingChamber *chamber = NULL;
695 Int_t debugLevel = fkReconstructor->IsDebugStreaming() ? fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) : 0;
696 TTreeSRedirector *cstreamer = fkReconstructor->IsDebugStreaming() ? fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker) : 0x0;
698 AliTRDseedV1 tracklet, *ptrTracklet = NULL;
699 // in case of stand alone tracking we store all the pointers to the tracklets in a temporary array
700 AliTRDseedV1 *tracklets[kNPlanes];
701 memset(tracklets, 0, sizeof(AliTRDseedV1 *) * kNPlanes);
702 for(Int_t ip = 0; ip < kNPlanes; ip++){
703 tracklets[ip] = t.GetTracklet(ip);
706 Bool_t kStoreIn(kTRUE), //
707 kPropagateIn(kTRUE),//
708 kUseTRD(fkRecoParam->IsOverPtThreshold(t.Pt()));// use TRD measurment to update Kalman
710 // Loop through the TRD layers
711 TGeoHMatrix *matrix = NULL;
713 for (Int_t ily=0, sm=-1, stk=-1, det=-1; ily < AliTRDgeometry::kNlayer; ily++) {
714 AliDebug(2, Form("Propagate to x[%d] = %7.2f", ily, fR[ily]));
716 // rough estimate of the entry point
717 if (!t.GetProlongation(fR[ily], y, z)){
719 t.SetStatus(AliTRDtrackV1::kProlongation);
720 AliDebug(4, Form("Failed Rough Prolongation to ly[%d] x[%7.2f] y[%7.2f] z[%7.2f]", ily, fR[ily], y, z));
724 // find sector / stack / detector
726 // TODO cross check with y value !
727 stk = fGeom->GetStack(z, ily);
728 det = stk>=0 ? AliTRDgeometry::GetDetector(ily, stk, sm) : -1;
729 matrix = det>=0 ? fGeom->GetClusterMatrix(det) : NULL;
730 AliDebug(3, Form("Propagate to det[%3d]", det));
732 // check if supermodule/chamber is installed
733 if( !fGeom->GetSMstatus(sm) ||
735 fGeom->IsHole(ily, stk, sm) ||
737 AliDebug(4, Form("Missing Geometry ly[%d]. Guess radial position", ily));
738 // propagate to the default radial position
739 if(fR[ily] > (fgkMaxStep + t.GetX()) && !PropagateToX(t, fR[ily], fgkMaxStep)){
741 t.SetStatus(AliTRDtrackV1::kPropagation);
742 AliDebug(4, "Failed Propagation [Missing Geometry]");
745 if(!AdjustSector(&t)){
747 t.SetStatus(AliTRDtrackV1::kAdjustSector);
748 AliDebug(4, "Failed Adjust Sector [Missing Geometry]");
751 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp){
753 t.SetStatus(AliTRDtrackV1::kSnp);
754 AliDebug(4, "Failed Max Snp [Missing Geometry]");
757 t.SetStatus(AliTRDtrackV1::kGeometry, ily);
761 // retrieve rotation matrix for the current chamber
762 Double_t loc[] = {AliTRDgeometry::AnodePos()- driftLength, 0., 0.};
763 Double_t glb[] = {0., 0., 0.};
764 matrix->LocalToMaster(loc, glb);
766 // Propagate to the radial distance of the current layer
767 x = glb[0] - fgkMaxStep;
768 if(x > (fgkMaxStep + t.GetX()) && !PropagateToX(t, x, fgkMaxStep)){
770 t.SetStatus(AliTRDtrackV1::kPropagation);
771 AliDebug(4, Form("Failed Initial Propagation to x[%7.2f]", x));
774 if(!AdjustSector(&t)){
776 t.SetStatus(AliTRDtrackV1::kAdjustSector);
777 AliDebug(4, "Failed Adjust Sector Start");
780 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp) {
782 t.SetStatus(AliTRDtrackV1::kSnp);
783 AliDebug(4, Form("Failed Max Snp[%f] MaxSnp[%f]", t.GetSnp(), fgkMaxSnp));
786 Bool_t doRecalculate = kFALSE;
787 if(sm != t.GetSector()){
789 doRecalculate = kTRUE;
791 if(stk != fGeom->GetStack(z, ily)){
792 stk = fGeom->GetStack(z, ily);
793 doRecalculate = kTRUE;
796 det = AliTRDgeometry::GetDetector(ily, stk, sm);
797 if(!(matrix = fGeom->GetClusterMatrix(det))){
798 t.SetStatus(AliTRDtrackV1::kGeometry, ily);
799 AliDebug(4, Form("Failed Geometry Matrix ly[%d]", ily));
802 matrix->LocalToMaster(loc, glb);
803 x = glb[0] - fgkMaxStep;
806 // check if track is well inside fiducial volume
807 if (!t.GetProlongation(x+fgkMaxStep, y, z)) {
809 t.SetStatus(AliTRDtrackV1::kProlongation);
810 AliDebug(4, Form("Failed Prolongation to x[%7.2f] y[%7.2f] z[%7.2f]", x+fgkMaxStep, y, z));
813 if(fGeom->IsOnBoundary(det, y, z, .5)){
814 t.SetStatus(AliTRDtrackV1::kBoundary, ily);
815 AliDebug(4, "Failed Track on Boundary");
818 // mark track as entering the FIDUCIAL volume of TRD
824 ptrTracklet = tracklets[ily];
825 if(!ptrTracklet){ // BUILD TRACKLET
826 AliDebug(3, Form("Building tracklet det[%d]", det));
827 // check data in supermodule
828 if(!fTrSec[sm].GetNChambers()){
829 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
830 AliDebug(4, "Failed NoClusters");
833 if(fTrSec[sm].GetX(ily) < 1.){
834 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
835 AliDebug(4, "Failed NoX");
839 // check data in chamber
840 if(!(chamber = fTrSec[sm].GetChamber(stk, ily))){
841 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
842 AliDebug(4, "Failed No Detector");
845 if(chamber->GetNClusters() < fgNTimeBins*fkRecoParam ->GetFindableClusters()){
846 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
847 AliDebug(4, "Failed Not Enough Clusters in Detector");
851 ptrTracklet = new(&tracklet) AliTRDseedV1(det);
852 ptrTracklet->SetReconstructor(fkReconstructor);
853 ptrTracklet->SetKink(t.IsKink());
854 ptrTracklet->SetPadPlane(fGeom->GetPadPlane(ily, stk));
855 ptrTracklet->SetX0(glb[0]+driftLength);
856 if(!tracklet.Init(&t)){
858 t.SetStatus(AliTRDtrackV1::kTrackletInit);
859 AliDebug(4, "Failed Tracklet Init");
862 if(!tracklet.AttachClusters(chamber, kTRUE)){
863 t.SetStatus(AliTRDtrackV1::kNoAttach, ily);
865 AliTRDseedV1 trackletCp(*ptrTracklet);
866 UChar_t status(t.GetStatusTRD(ily));
867 (*cstreamer) << "FollowBackProlongation2"
868 <<"status=" << status
869 <<"tracklet.=" << &trackletCp
872 AliDebug(4, "Failed Attach Clusters");
875 AliDebug(3, Form("Number of Clusters in Tracklet: %d", tracklet.GetN()));
876 if(tracklet.GetN() < fgNTimeBins*fkRecoParam ->GetFindableClusters()){
877 t.SetStatus(AliTRDtrackV1::kNoClustersTracklet, ily);
879 AliTRDseedV1 trackletCp(*ptrTracklet);
880 UChar_t status(t.GetStatusTRD(ily));
881 (*cstreamer) << "FollowBackProlongation2"
882 <<"status=" << status
883 <<"tracklet.=" << &trackletCp
886 AliDebug(4, "Failed N Clusters Attached");
889 ptrTracklet->UpdateUsed();
890 } else AliDebug(2, Form("Use external tracklet ly[%d]", ily));
891 // propagate track to the radial position of the tracklet
892 ptrTracklet->UseClusters(); // TODO ? do we need this here ?
893 // fit tracklet no tilt correction
894 if(!ptrTracklet->Fit(kFALSE)){
895 t.SetStatus(AliTRDtrackV1::kNoFit, ily);
896 AliDebug(4, "Failed Tracklet Fit");
899 x = ptrTracklet->GetX(); //GetX0();
900 if(x > (fgkMaxStep + t.GetX()) && !PropagateToX(t, x, fgkMaxStep)) {
902 t.SetStatus(AliTRDtrackV1::kPropagation);
903 AliDebug(4, Form("Failed Propagation to Tracklet x[%7.2f]", x));
906 if(!AdjustSector(&t)) {
908 t.SetStatus(AliTRDtrackV1::kAdjustSector);
909 AliDebug(4, "Failed Adjust Sector");
912 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp) {
914 t.SetStatus(AliTRDtrackV1::kSnp);
915 AliDebug(4, Form("Failed Max Snp[%f] MaxSnp[%f]", t.GetSnp(), fgkMaxSnp));
920 kPropagateIn = kFALSE;
922 Double_t cov[3]; ptrTracklet->GetCovAt(x, cov);
923 Double_t p[2] = { ptrTracklet->GetY(), ptrTracklet->GetZ()};
924 Double_t chi2 = ((AliExternalTrackParam)t).GetPredictedChi2(p, cov);
925 // update Kalman with the TRD measurement
926 if(chi2>1e+10){ // TODO
927 t.SetStatus(AliTRDtrackV1::kChi2, ily);
929 UChar_t status(t.GetStatusTRD());
930 AliTRDseedV1 trackletCp(*ptrTracklet);
931 AliTRDtrackV1 trackCp(t);
933 (*cstreamer) << "FollowBackProlongation1"
934 << "status=" << status
935 << "tracklet.=" << &trackletCp
936 << "track.=" << &trackCp
939 AliDebug(4, Form("Failed Chi2[%f]", chi2));
942 if(!t.Update(p, cov, chi2, kUseTRD)) {
944 t.SetStatus(AliTRDtrackV1::kUpdate);
946 UChar_t status(t.GetStatusTRD());
947 AliTRDseedV1 trackletCp(*ptrTracklet);
948 AliTRDtrackV1 trackCp(t);
950 (*cstreamer) << "FollowBackProlongation1"
951 << "status=" << status
952 << "tracklet.=" << &trackletCp
953 << "track.=" << &trackCp
956 AliDebug(4, Form("Failed Track Update @ y[%7.2f] z[%7.2f] s2y[%f] s2z[%f] covyz[%f]", p[0], p[1], cov[0], cov[2], cov[1]));
960 AliTracker::FillResiduals(&t, p, cov, ptrTracklet->GetVolumeId());
963 // load tracklet to the tracker
964 ptrTracklet->Update(&t);
965 ptrTracklet = SetTracklet(ptrTracklet);
966 Int_t index(fTracklets->GetEntriesFast()-1);
967 t.SetTracklet(ptrTracklet, index);
968 n += ptrTracklet->GetN();
969 AliDebug(2, Form("Setting Tracklet[%d] @ Idx[%d]", ily, index));
971 // Reset material budget if 2 consecutive gold
972 // if(ilayer>0 && t.GetTracklet(ilayer-1) && ptrTracklet->GetN() + t.GetTracklet(ilayer-1)->GetN() > 20) t.SetBudget(2, 0.);
974 // Make backup of the track until is gold
976 if((failed = t.MakeBackupTrack())) AliDebug(2, Form("Failed backup on cut[%d]", failed));
979 //printf("clusters[%d] chi2[%f] x[%f] status[%d ", n, t.GetChi2(), t.GetX(), t.GetStatusTRD());
980 //for(int i=0; i<6; i++) printf("%d ", t.GetStatusTRD(i)); printf("]\n");
983 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
984 AliTRDtrackV1 track(t);
986 (*cstreamer) << "FollowBackProlongation0"
987 << "EventNumber=" << eventNumber
989 << "track.=" << &track
996 //_________________________________________________________________________
997 Float_t AliTRDtrackerV1::FitRieman(AliTRDseedV1 *tracklets, Double_t *chi2, Int_t *const planes){
999 // Fits a Riemann-circle to the given points without tilting pad correction.
1000 // The fit is performed using an instance of the class AliRieman (equations
1001 // and transformations see documentation of this class)
1002 // Afterwards all the tracklets are Updated
1004 // Parameters: - Array of tracklets (AliTRDseedV1)
1005 // - Storage for the chi2 values (beginning with direction z)
1006 // - Seeding configuration
1007 // Output: - The curvature
1009 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1011 Int_t allplanes[] = {0, 1, 2, 3, 4, 5};
1012 Int_t *ppl = &allplanes[0];
1013 Int_t maxLayers = 6;
1018 for(Int_t il = 0; il < maxLayers; il++){
1019 if(!tracklets[ppl[il]].IsOK()) continue;
1020 fitter->AddPoint(tracklets[ppl[il]].GetX0(), tracklets[ppl[il]].GetYfit(0), tracklets[ppl[il]].GetZfit(0),1,10);
1023 // Set the reference position of the fit and calculate the chi2 values
1024 memset(chi2, 0, sizeof(Double_t) * 2);
1025 for(Int_t il = 0; il < maxLayers; il++){
1026 // Reference positions
1027 tracklets[ppl[il]].Init(fitter);
1030 if((!tracklets[ppl[il]].IsOK()) && (!planes)) continue;
1031 chi2[0] += tracklets[ppl[il]].GetChi2Y();
1032 chi2[1] += tracklets[ppl[il]].GetChi2Z();
1034 return fitter->GetC();
1037 //_________________________________________________________________________
1038 void AliTRDtrackerV1::FitRieman(AliTRDcluster **seedcl, Double_t chi2[2])
1041 // Performs a Riemann helix fit using the seedclusters as spacepoints
1042 // Afterwards the chi2 values are calculated and the seeds are updated
1044 // Parameters: - The four seedclusters
1045 // - The tracklet array (AliTRDseedV1)
1046 // - The seeding configuration
1051 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1053 for(Int_t i = 0; i < 4; i++){
1054 fitter->AddPoint(seedcl[i]->GetX(), seedcl[i]->GetY(), seedcl[i]->GetZ(), 1., 10.);
1059 // Update the seed and calculated the chi2 value
1060 chi2[0] = 0; chi2[1] = 0;
1061 for(Int_t ipl = 0; ipl < kNSeedPlanes; ipl++){
1063 chi2[0] += (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX()));
1064 chi2[1] += (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX()));
1069 //_________________________________________________________________________
1070 Float_t AliTRDtrackerV1::FitTiltedRiemanConstraint(AliTRDseedV1 *tracklets, Double_t zVertex)
1073 // Fits a helix to the clusters. Pad tilting is considered. As constraint it is
1074 // assumed that the vertex position is set to 0.
1075 // This method is very usefull for high-pt particles
1076 // Basis for the fit: (x - x0)^2 + (y - y0)^2 - R^2 = 0
1077 // x0, y0: Center of the circle
1078 // Measured y-position: ymeas = y - tan(phiT)(zc - zt)
1079 // zc: center of the pad row
1080 // Equation which has to be fitted (after transformation):
1081 // a + b * u + e * v + 2*(ymeas + tan(phiT)(z - zVertex))*t = 0
1083 // t = 1/(x^2 + y^2)
1085 // v = 2 * x * tan(phiT) * t
1086 // Parameters in the equation:
1087 // a = -1/y0, b = x0/y0, e = dz/dx
1089 // The Curvature is calculated by the following equation:
1090 // - curv = a/Sqrt(b^2 + 1) = 1/R
1091 // Parameters: - the 6 tracklets
1092 // - the Vertex constraint
1093 // Output: - the Chi2 value of the track
1098 TLinearFitter *fitter = GetTiltedRiemanFitterConstraint();
1099 fitter->StoreData(kTRUE);
1100 fitter->ClearPoints();
1101 AliTRDcluster *cl = NULL;
1103 Float_t x, y, z, w, t, error, tilt;
1106 for(Int_t ilr = 0; ilr < AliTRDgeometry::kNlayer; ilr++){
1107 if(!tracklets[ilr].IsOK()) continue;
1108 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1109 if(!tracklets[ilr].IsUsable(itb)) continue;
1110 cl = tracklets[ilr].GetClusters(itb);
1111 if(!cl->IsInChamber()) continue;
1115 tilt = tracklets[ilr].GetTilt();
1117 t = 1./(x * x + y * y);
1118 uvt[0] = 2. * x * t;
1119 uvt[1] = 2. * x * t * tilt ;
1120 w = 2. * (y + tilt * (z - zVertex)) * t;
1121 error = 2. * TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) * t;
1122 fitter->AddPoint(uvt, w, error);
1128 // Calculate curvature
1129 Double_t a = fitter->GetParameter(0);
1130 Double_t b = fitter->GetParameter(1);
1131 Double_t curvature = a/TMath::Sqrt(b*b + 1);
1133 Float_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1134 for(Int_t ip = 0; ip < AliTRDtrackerV1::kNPlanes; ip++)
1135 tracklets[ip].SetC(curvature);
1137 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker()) >= 5){
1138 //Linear Model on z-direction
1139 Double_t xref = CalculateReferenceX(tracklets); // Relative to the middle of the stack
1140 Double_t slope = fitter->GetParameter(2);
1141 Double_t zref = slope * xref;
1142 Float_t chi2Z = CalculateChi2Z(tracklets, zref, slope, xref);
1143 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1144 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1145 TTreeSRedirector &treeStreamer = *fkReconstructor->GetDebugStream(AliTRDReconstructor::kTracker);
1146 treeStreamer << "FitTiltedRiemanConstraint"
1147 << "EventNumber=" << eventNumber
1148 << "CandidateNumber=" << candidateNumber
1149 << "Curvature=" << curvature
1150 << "Chi2Track=" << chi2track
1151 << "Chi2Z=" << chi2Z
1158 //_________________________________________________________________________
1159 Float_t AliTRDtrackerV1::FitTiltedRieman(AliTRDseedV1 *tracklets, Bool_t sigError)
1162 // Performs a Riemann fit taking tilting pad correction into account
1163 // The equation of a Riemann circle, where the y position is substituted by the
1164 // measured y-position taking pad tilting into account, has to be transformed
1165 // into a 4-dimensional hyperplane equation
1166 // Riemann circle: (x-x0)^2 + (y-y0)^2 -R^2 = 0
1167 // Measured y-Position: ymeas = y - tan(phiT)(zc - zt)
1168 // zc: center of the pad row
1169 // zt: z-position of the track
1170 // The z-position of the track is assumed to be linear dependent on the x-position
1171 // Transformed equation: a + b * u + c * t + d * v + e * w - 2 * (ymeas + tan(phiT) * zc) * t = 0
1172 // Transformation: u = 2 * x * t
1173 // v = 2 * tan(phiT) * t
1174 // w = 2 * tan(phiT) * (x - xref) * t
1175 // t = 1 / (x^2 + ymeas^2)
1176 // Parameters: a = -1/y0
1178 // c = (R^2 -x0^2 - y0^2)/y0
1181 // If the offset respectively the slope in z-position is impossible, the parameters are fixed using
1182 // results from the simple riemann fit. Afterwards the fit is redone.
1183 // The curvature is calculated according to the formula:
1184 // curv = a/(1 + b^2 + c*a) = 1/R
1186 // Paramters: - Array of tracklets (connected to the track candidate)
1187 // - Flag selecting the error definition
1188 // Output: - Chi2 values of the track (in Parameter list)
1190 TLinearFitter *fitter = GetTiltedRiemanFitter();
1191 fitter->StoreData(kTRUE);
1192 fitter->ClearPoints();
1193 AliTRDLeastSquare zfitter;
1194 AliTRDcluster *cl = NULL;
1196 Double_t xref = CalculateReferenceX(tracklets);
1197 Double_t x, y, z, t, tilt, dx, w, we, erry, errz;
1198 Double_t uvt[4], sumPolY[5], sumPolZ[3];
1199 memset(sumPolY, 0, sizeof(Double_t) * 5);
1200 memset(sumPolZ, 0, sizeof(Double_t) * 3);
1202 // Containers for Least-square fitter
1203 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1204 if(!tracklets[ipl].IsOK()) continue;
1205 tilt = tracklets[ipl].GetTilt();
1206 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1207 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1208 if(!cl->IsInChamber()) continue;
1209 if (!tracklets[ipl].IsUsable(itb)) continue;
1216 uvt[0] = 2. * x * t;
1218 uvt[2] = 2. * tilt * t;
1219 uvt[3] = 2. * tilt * dx * t;
1220 w = 2. * (y + tilt*z) * t;
1221 // error definition changes for the different calls
1223 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) : 0.2;
1224 fitter->AddPoint(uvt, w, we);
1225 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1226 // adding points for covariance matrix estimation
1227 erry = 1./(TMath::Sqrt(cl->GetSigmaY2()) + 0.1); // 0.1 is a systematic error (due to misalignment and miscalibration)
1229 errz = 1./cl->GetSigmaZ2();
1230 for(Int_t ipol = 0; ipol < 5; ipol++){
1231 sumPolY[ipol] += erry;
1234 sumPolZ[ipol] += errz;
1244 Double_t offset = fitter->GetParameter(3);
1245 Double_t slope = fitter->GetParameter(4);
1247 // Linear fitter - not possible to make boundaries
1248 // Do not accept non possible z and dzdx combinations
1249 Bool_t acceptablez = kTRUE;
1250 Double_t zref = 0.0;
1251 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1252 if(!tracklets[iLayer].IsOK()) continue;
1253 zref = offset + slope * (tracklets[iLayer].GetX0() - xref);
1254 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1255 acceptablez = kFALSE;
1258 Double_t dzmf = zfitter.GetFunctionParameter(1);
1259 Double_t zmf = zfitter.GetFunctionValue(&xref);
1260 fgTiltedRieman->FixParameter(3, zmf);
1261 fgTiltedRieman->FixParameter(4, dzmf);
1263 fitter->ReleaseParameter(3);
1264 fitter->ReleaseParameter(4);
1265 offset = fitter->GetParameter(3);
1266 slope = fitter->GetParameter(4);
1269 // Calculate Curvarture
1270 Double_t a = fitter->GetParameter(0);
1271 Double_t b = fitter->GetParameter(1);
1272 Double_t c = fitter->GetParameter(2);
1273 Double_t curvature = 1.0 + b*b - c*a;
1274 if (curvature > 0.0)
1275 curvature = a / TMath::Sqrt(curvature);
1277 Double_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1279 // Prepare error calculation
1280 TMatrixD covarPolY(3,3);
1281 covarPolY(0,0) = sumPolY[0]; covarPolY(1,1) = sumPolY[2]; covarPolY(2,2) = sumPolY[4];
1282 covarPolY(0,1) = covarPolY(1,0) = sumPolY[1];
1283 covarPolY(0,2) = covarPolY(2,0) = sumPolY[2];
1284 covarPolY(2,1) = covarPolY(1,2) = sumPolY[3];
1286 TMatrixD covarPolZ(2,2);
1287 covarPolZ(0,0) = sumPolZ[0]; covarPolZ(1,1) = sumPolZ[2];
1288 covarPolZ(1,0) = covarPolZ(0,1) = sumPolZ[1];
1291 // Update the tracklets
1292 Double_t x1, dy, dz;
1294 memset(cov, 0, sizeof(Double_t) * 15);
1295 for(Int_t iLayer = 0; iLayer < AliTRDtrackerV1::kNPlanes; iLayer++) {
1297 x = tracklets[iLayer].GetX0();
1303 memset(cov, 0, sizeof(Double_t) * 3);
1304 TMatrixD transform(3,3);
1307 transform(0,2) = x*x;
1311 TMatrixD covariance(transform, TMatrixD::kMult, covarPolY);
1312 covariance *= transform.T();
1313 TMatrixD transformZ(2,2);
1314 transformZ(0,0) = transformZ(1,1) = 1;
1315 transformZ(0,1) = x;
1316 TMatrixD covarZ(transformZ, TMatrixD::kMult, covarPolZ);
1317 covarZ *= transformZ.T();
1318 // y: R^2 = (x - x0)^2 + (y - y0)^2
1319 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1320 // R = Sqrt() = 1/Curvature
1321 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
1322 Double_t res = (x * a + b); // = (x - x0)/y0
1324 res = 1.0 - c * a + b * b - res; // = (R^2 - (x - x0)^2)/y0^2
1326 res = TMath::Sqrt(res);
1327 y = (1.0 - res) / a;
1329 cov[0] = covariance(0,0);
1330 cov[2] = covarZ(0,0);
1333 // dy: R^2 = (x - x0)^2 + (y - y0)^2
1334 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
1335 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1336 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
1337 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
1338 Double_t x0 = -b / a;
1339 if (-c * a + b * b + 1 > 0) {
1340 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
1341 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
1342 if (a < 0) yderiv *= -1.0;
1346 z = offset + slope * (x - xref);
1348 tracklets[iLayer].SetYref(0, y);
1349 tracklets[iLayer].SetYref(1, dy);
1350 tracklets[iLayer].SetZref(0, z);
1351 tracklets[iLayer].SetZref(1, dz);
1352 tracklets[iLayer].SetC(curvature);
1353 tracklets[iLayer].SetCovRef(cov);
1354 tracklets[iLayer].SetChi2(chi2track);
1357 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >=5){
1358 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
1359 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1360 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1361 Double_t chi2z = CalculateChi2Z(tracklets, offset, slope, xref);
1362 cstreamer << "FitTiltedRieman0"
1363 << "EventNumber=" << eventNumber
1364 << "CandidateNumber=" << candidateNumber
1366 << "Chi2Z=" << chi2z
1373 //____________________________________________________________________
1374 Double_t AliTRDtrackerV1::FitLine(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t err, Int_t np, AliTrackPoint *points)
1377 // Fit track with a staight line
1378 // Fills an AliTrackPoint array with np points
1379 // Function should be used to refit tracks when no magnetic field was on
1381 AliTRDLeastSquare yfitter, zfitter;
1382 AliTRDcluster *cl = NULL;
1384 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1386 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1387 if(!(tracklet = track->GetTracklet(ipl))) continue;
1388 if(!tracklet->IsOK()) continue;
1389 new(&work[ipl]) AliTRDseedV1(*tracklet);
1391 tracklets = &work[0];
1394 Double_t xref = CalculateReferenceX(tracklets);
1395 Double_t x, y, z, dx, ye, yr, tilt;
1396 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1397 if(!tracklets[ipl].IsOK()) continue;
1398 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1399 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1400 if (!tracklets[ipl].IsUsable(itb)) continue;
1404 zfitter.AddPoint(&dx, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1408 Double_t z0 = zfitter.GetFunctionParameter(0);
1409 Double_t dzdx = zfitter.GetFunctionParameter(1);
1410 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1411 if(!tracklets[ipl].IsOK()) continue;
1412 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1413 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1414 if (!tracklets[ipl].IsUsable(itb)) continue;
1418 tilt = tracklets[ipl].GetTilt();
1420 yr = y + tilt*(z - z0 - dzdx*dx);
1421 // error definition changes for the different calls
1422 ye = tilt*TMath::Sqrt(cl->GetSigmaZ2());
1423 ye += err ? tracklets[ipl].GetSigmaY() : 0.2;
1424 yfitter.AddPoint(&dx, yr, ye);
1428 Double_t y0 = yfitter.GetFunctionParameter(0);
1429 Double_t dydx = yfitter.GetFunctionParameter(1);
1430 Double_t chi2 = 0.;//yfitter.GetChisquare()/Double_t(nPoints);
1432 //update track points array
1435 for(int ip=0; ip<np; ip++){
1436 points[ip].GetXYZ(xyz);
1437 xyz[1] = y0 + dydx * (xyz[0] - xref);
1438 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1439 points[ip].SetXYZ(xyz);
1446 //_________________________________________________________________________
1447 Double_t AliTRDtrackerV1::FitRiemanTilt(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t sigError, Int_t np, AliTrackPoint *points)
1450 // Performs a Riemann fit taking tilting pad correction into account
1452 // Paramters: - Array of tracklets (connected to the track candidate)
1453 // - Flag selecting the error definition
1454 // Output: - Chi2 values of the track (in Parameter list)
1456 // The equations which has to be solved simultaneously are:
1458 // R^{2} = (x-x_{0})^{2} + (y^{*}-y_{0})^{2}
1459 // y^{*} = y - tg(h)(z - z_{t})
1460 // z_{t} = z_{0}+dzdx*(x-x_{r})
1462 // with (x, y, z) the coordinate of the cluster, (x_0, y_0, z_0) the coordinate of the center of the Riemann circle,
1463 // R its radius, x_r a constant refrence radial position in the middle of the TRD stack and dzdx the slope of the
1464 // track in the x-z plane. Using the following transformations
1466 // t = 1 / (x^{2} + y^{2})
1468 // v = 2 * tan(h) * t
1469 // w = 2 * tan(h) * (x - x_{r}) * t
1471 // One gets the following linear equation
1473 // a + b * u + c * t + d * v + e * w = 2 * (y + tg(h) * z) * t
1475 // where the coefficients have the following meaning
1479 // c = (R^{2} -x_{0}^{2} - y_{0}^{2})/y_{0}
1483 // The error calculation for the free term is thus
1485 // #sigma = 2 * #sqrt{#sigma^{2}_{y} + (tilt corr ...) + tg^{2}(h) * #sigma^{2}_{z}} * t
1488 // From this simple model one can compute chi^2 estimates and a rough approximation of pt from the curvature according
1491 // C = 1/R = a/(1 + b^{2} + c*a)
1495 // M.Ivanov <M.Ivanov@gsi.de>
1496 // A.Bercuci <A.Bercuci@gsi.de>
1497 // M.Fasel <M.Fasel@gsi.de>
1499 TLinearFitter *fitter = GetTiltedRiemanFitter();
1500 fitter->StoreData(kTRUE);
1501 fitter->ClearPoints();
1502 AliTRDLeastSquare zfitter;
1503 AliTRDcluster *cl = NULL;
1505 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1507 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1508 if(!(tracklet = track->GetTracklet(ipl))) continue;
1509 if(!tracklet->IsOK()) continue;
1510 new(&work[ipl]) AliTRDseedV1(*tracklet);
1512 tracklets = &work[0];
1515 Double_t xref = CalculateReferenceX(tracklets);
1516 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1517 Form("\nx0[(0)%6.2f (1)%6.2f (2)%6.2f (3)%6.2f (4)%6.2f (5)%6.2f] xref[%6.2f]", tracklets[0].GetX0(), tracklets[1].GetX0(), tracklets[2].GetX0(), tracklets[3].GetX0(), tracklets[4].GetX0(), tracklets[5].GetX0(), xref));
1518 Double_t x, y, z, t, tilt, dx, w, we;
1521 // Containers for Least-square fitter
1522 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1523 if(!tracklets[ipl].IsOK()) continue;
1524 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1525 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1526 //if (!tracklets[ipl].IsUsable(itb)) continue;
1530 tilt = tracklets[ipl].GetTilt();
1534 uvt[0] = 2. * x * t;
1536 uvt[2] = 2. * tilt * t;
1537 uvt[3] = 2. * tilt * dx * t;
1538 w = 2. * (y + tilt*z) * t;
1539 // error definition changes for the different calls
1541 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()) : 0.2;
1542 fitter->AddPoint(uvt, w, we);
1543 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1547 if(fitter->Eval()) return 1.E10;
1549 Double_t z0 = fitter->GetParameter(3);
1550 Double_t dzdx = fitter->GetParameter(4);
1553 // Linear fitter - not possible to make boundaries
1554 // Do not accept non possible z and dzdx combinations
1555 Bool_t accept = kTRUE;
1556 Double_t zref = 0.0;
1557 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1558 if(!tracklets[iLayer].IsOK()) continue;
1559 zref = z0 + dzdx * (tracklets[iLayer].GetX0() - xref);
1560 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1565 Double_t dzmf = zfitter.GetFunctionParameter(1);
1566 Double_t zmf = zfitter.GetFunctionValue(&xref);
1567 fitter->FixParameter(3, zmf);
1568 fitter->FixParameter(4, dzmf);
1570 fitter->ReleaseParameter(3);
1571 fitter->ReleaseParameter(4);
1572 z0 = fitter->GetParameter(3); // = zmf ?
1573 dzdx = fitter->GetParameter(4); // = dzmf ?
1576 // Calculate Curvature
1577 Double_t a = fitter->GetParameter(0);
1578 Double_t b = fitter->GetParameter(1);
1579 Double_t c = fitter->GetParameter(2);
1580 Double_t y0 = 1. / a;
1581 Double_t x0 = -b * y0;
1582 Double_t tmp = y0*y0 + x0*x0 - c*y0;
1583 if(tmp<=0.) return 1.E10;
1584 Double_t radius = TMath::Sqrt(tmp);
1585 Double_t curvature = 1.0 + b*b - c*a;
1586 if (curvature > 0.0) curvature = a / TMath::Sqrt(curvature);
1588 // Calculate chi2 of the fit
1589 Double_t chi2 = fitter->GetChisquare()/Double_t(nPoints);
1590 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1591 Form("x0[%6.2f] y0[%6.2f] R[%6.2f] chi2[%f]\n", x0, y0, radius, chi2));
1593 // Update the tracklets
1595 for(Int_t ip = 0; ip < kNPlanes; ip++) {
1596 x = tracklets[ip].GetX0();
1597 tmp = radius*radius-(x-x0)*(x-x0);
1598 if(tmp <= 0.) continue;
1599 tmp = TMath::Sqrt(tmp);
1601 // y: R^2 = (x - x0)^2 + (y - y0)^2
1602 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1603 tracklets[ip].SetYref(0, y0 - (y0>0.?1.:-1)*tmp);
1604 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1605 tracklets[ip].SetYref(1, (x - x0) / tmp);
1606 tracklets[ip].SetZref(0, z0 + dzdx * (x - xref));
1607 tracklets[ip].SetZref(1, dzdx);
1608 tracklets[ip].SetC(curvature);
1609 tracklets[ip].SetChi2(chi2);
1612 //update track points array
1615 for(int ip=0; ip<np; ip++){
1616 points[ip].GetXYZ(xyz);
1617 xyz[1] = TMath::Abs(xyz[0] - x0) > radius ? 100. : y0 - (y0>0.?1.:-1.)*TMath::Sqrt((radius-(xyz[0]-x0))*(radius+(xyz[0]-x0)));
1618 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1619 points[ip].SetXYZ(xyz);
1627 //____________________________________________________________________
1628 Double_t AliTRDtrackerV1::FitKalman(AliTRDtrackV1 *track, AliTRDseedV1 * const tracklets, Bool_t up, Int_t np, AliTrackPoint *points)
1630 // Kalman filter implementation for the TRD.
1631 // It returns the positions of the fit in the array "points"
1633 // Author : A.Bercuci@gsi.de
1635 // printf("Start track @ x[%f]\n", track->GetX());
1637 //prepare marker points along the track
1638 Int_t ip = np ? 0 : 1;
1640 if((up?-1:1) * (track->GetX() - points[ip].GetX()) > 0.) break;
1641 //printf("AliTRDtrackerV1::FitKalman() : Skip track marker x[%d] = %7.3f. Before track start ( %7.3f ).\n", ip, points[ip].GetX(), track->GetX());
1644 //if(points) printf("First marker point @ x[%d] = %f\n", ip, points[ip].GetX());
1647 AliTRDseedV1 tracklet, *ptrTracklet = NULL;
1649 //Loop through the TRD planes
1650 for (Int_t jplane = 0; jplane < kNPlanes; jplane++) {
1651 // GET TRACKLET OR BUILT IT
1652 Int_t iplane = up ? jplane : kNPlanes - 1 - jplane;
1654 if(!(ptrTracklet = &tracklets[iplane])) continue;
1656 if(!(ptrTracklet = track->GetTracklet(iplane))){
1657 /*AliTRDtrackerV1 *tracker = NULL;
1658 if(!(tracker = dynamic_cast<AliTRDtrackerV1*>( AliTRDrecoParam:Tracker()))) continue;
1659 ptrTracklet = new(&tracklet) AliTRDseedV1(iplane);
1660 if(!tracker->MakeTracklet(ptrTracklet, track)) */
1664 if(!ptrTracklet->IsOK()) continue;
1666 Double_t x = ptrTracklet->GetX0();
1669 //don't do anything if next marker is after next update point.
1670 if((up?-1:1) * (points[ip].GetX() - x) - fgkMaxStep < 0) break;
1671 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1673 Double_t xyz[3]; // should also get the covariance
1675 track->Global2LocalPosition(xyz, track->GetAlpha());
1676 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1679 // printf("plane[%d] tracklet[%p] x[%f]\n", iplane, ptrTracklet, x);
1681 // Propagate closer to the next update point
1682 if(((up?-1:1) * (x - track->GetX()) + fgkMaxStep < 0) && !PropagateToX(*track, x + (up?-1:1)*fgkMaxStep, fgkMaxStep)) return -1.;
1684 if(!AdjustSector(track)) return -1;
1685 if(TMath::Abs(track->GetSnp()) > fgkMaxSnp) return -1;
1687 //load tracklet to the tracker and the track
1689 if((index = FindTracklet(ptrTracklet)) < 0){
1690 ptrTracklet = SetTracklet(&tracklet);
1691 index = fTracklets->GetEntriesFast()-1;
1693 track->SetTracklet(ptrTracklet, index);*/
1696 // register tracklet to track with tracklet creation !!
1697 // PropagateBack : loaded tracklet to the tracker and update index
1698 // RefitInward : update index
1699 // MakeTrack : loaded tracklet to the tracker and update index
1700 if(!tracklets) track->SetTracklet(ptrTracklet, -1);
1703 //Calculate the mean material budget along the path inside the chamber
1704 Double_t xyz0[3]; track->GetXYZ(xyz0);
1705 Double_t alpha = track->GetAlpha();
1706 Double_t xyz1[3], y, z;
1707 if(!track->GetProlongation(x, y, z)) return -1;
1708 xyz1[0] = x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
1709 xyz1[1] = +x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
1711 if(TMath::Abs(xyz0[0] - xyz1[0]) < 1e-3 && TMath::Abs(xyz0[1] - xyz1[1]) < 1e-3) continue; // check wheter we are at the same global x position
1713 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param) <=0.) break;
1714 Double_t xrho = param[0]*param[4]; // density*length
1715 Double_t xx0 = param[1]; // radiation length
1717 //Propagate the track
1718 track->PropagateTo(x, xx0, xrho);
1719 if (!AdjustSector(track)) break;
1722 Double_t cov[3]; ptrTracklet->GetCovAt(x, cov);
1723 Double_t p[2] = { ptrTracklet->GetY(), ptrTracklet->GetZ()};
1724 Double_t chi2 = ((AliExternalTrackParam*)track)->GetPredictedChi2(p, cov);
1725 if(chi2<1e+10) track->Update(p, cov, chi2);
1728 //Reset material budget if 2 consecutive gold
1729 if(iplane>0 && track->GetTracklet(iplane-1) && ptrTracklet->GetN() + track->GetTracklet(iplane-1)->GetN() > 20) track->SetBudget(2, 0.);
1730 } // end planes loop
1734 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1736 Double_t xyz[3]; // should also get the covariance
1738 track->Global2LocalPosition(xyz, track->GetAlpha());
1739 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1743 return track->GetChi2();
1746 //_________________________________________________________________________
1747 Float_t AliTRDtrackerV1::CalculateChi2Z(AliTRDseedV1 *tracklets, Double_t offset, Double_t slope, Double_t xref)
1750 // Calculates the chi2-value of the track in z-Direction including tilting pad correction.
1751 // A linear dependence on the x-value serves as a model.
1752 // The parameters are related to the tilted Riemann fit.
1753 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
1754 // - the offset for the reference x
1756 // - the reference x position
1757 // Output: - The Chi2 value of the track in z-Direction
1759 Float_t chi2Z = 0, nLayers = 0;
1760 for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNlayer; iLayer++) {
1761 if(!tracklets[iLayer].IsOK()) continue;
1762 Double_t z = offset + slope * (tracklets[iLayer].GetX0() - xref);
1763 chi2Z += TMath::Abs(tracklets[iLayer].GetZfit(0) - z);
1766 chi2Z /= TMath::Max((nLayers - 3.0),1.0);
1770 //_____________________________________________________________________________
1771 Int_t AliTRDtrackerV1::PropagateToX(AliTRDtrackV1 &t, Double_t xToGo, Double_t maxStep)
1774 // Starting from current X-position of track <t> this function
1775 // extrapolates the track up to radial position <xToGo>.
1776 // Returns 1 if track reaches the plane, and 0 otherwise
1779 const Double_t kEpsilon = 0.00001;
1781 // Current track X-position
1782 Double_t xpos = t.GetX();
1784 // Direction: inward or outward
1785 Double_t dir = (xpos < xToGo) ? 1.0 : -1.0;
1787 while (((xToGo - xpos) * dir) > kEpsilon) {
1796 // The next step size
1797 Double_t step = dir * TMath::Min(TMath::Abs(xToGo-xpos),maxStep);
1799 // Get the global position of the starting point
1802 // X-position after next step
1805 // Get local Y and Z at the X-position of the next step
1806 if(t.GetProlongation(x,y,z)<0) return 0; // No prolongation possible
1808 // The global position of the end point of this prolongation step
1809 xyz1[0] = x * TMath::Cos(t.GetAlpha()) - y * TMath::Sin(t.GetAlpha());
1810 xyz1[1] = +x * TMath::Sin(t.GetAlpha()) + y * TMath::Cos(t.GetAlpha());
1813 // Calculate the mean material budget between start and
1814 // end point of this prolongation step
1815 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param)<=0.) return 0;
1817 // Propagate the track to the X-position after the next step
1818 if (!t.PropagateTo(x, param[1], param[0]*param[4])) return 0;
1820 // Rotate the track if necessary
1823 // New track X-position
1833 //_____________________________________________________________________________
1834 Int_t AliTRDtrackerV1::ReadClusters(TClonesArray* &array, TTree *clusterTree) const
1837 // Reads AliTRDclusters from the file.
1838 // The names of the cluster tree and branches
1839 // should match the ones used in AliTRDclusterizer::WriteClusters()
1842 Int_t nsize = Int_t(clusterTree->GetTotBytes() / (sizeof(AliTRDcluster)));
1843 TObjArray *clusterArray = new TObjArray(nsize+1000);
1845 TBranch *branch = clusterTree->GetBranch("TRDcluster");
1847 AliError("Can't get the branch !");
1850 branch->SetAddress(&clusterArray);
1853 Float_t nclusters = fkRecoParam->GetNClusters();
1854 if(fkReconstructor->IsHLT()) nclusters /= AliTRDgeometry::kNsector;
1855 array = new TClonesArray("AliTRDcluster", Int_t(nclusters));
1856 array->SetOwner(kTRUE);
1859 // Loop through all entries in the tree
1860 Int_t nEntries = (Int_t) clusterTree->GetEntries();
1863 AliTRDcluster *c = NULL;
1864 for (Int_t iEntry = 0; iEntry < nEntries; iEntry++) {
1866 nbytes += clusterTree->GetEvent(iEntry);
1868 // Get the number of points in the detector
1869 Int_t nCluster = clusterArray->GetEntriesFast();
1870 for (Int_t iCluster = 0; iCluster < nCluster; iCluster++) {
1871 if(!(c = (AliTRDcluster *) clusterArray->UncheckedAt(iCluster))) continue;
1872 new((*fClusters)[ncl++]) AliTRDcluster(*c);
1873 delete (clusterArray->RemoveAt(iCluster));
1877 delete clusterArray;
1882 //_____________________________________________________________________________
1883 Int_t AliTRDtrackerV1::LoadClusters(TTree *cTree)
1886 // Fills clusters into TRD tracking sectors
1889 fkRecoParam = fkReconstructor->GetRecoParam(); // load reco param for this event
1891 if(!fkReconstructor->IsWritingClusters()){
1892 fClusters = AliTRDReconstructor::GetClusters();
1894 if (ReadClusters(fClusters, cTree)) {
1895 AliError("Problem with reading the clusters !");
1901 if(!fClusters || !fClusters->GetEntriesFast()){
1902 AliInfo("No TRD clusters");
1907 BuildTrackingContainers();
1909 //Int_t ncl = fClusters->GetEntriesFast();
1910 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1915 //_____________________________________________________________________________
1916 Int_t AliTRDtrackerV1::LoadClusters(TClonesArray * const clusters)
1919 // Fills clusters into TRD tracking sectors
1920 // Function for use in the HLT
1922 if(!clusters || !clusters->GetEntriesFast()){
1923 AliInfo("No TRD clusters");
1927 fClusters = clusters;
1930 fkRecoParam = fkReconstructor->GetRecoParam(); // load reco param for this event
1931 BuildTrackingContainers();
1933 //Int_t ncl = fClusters->GetEntriesFast();
1934 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1940 //____________________________________________________________________
1941 Int_t AliTRDtrackerV1::BuildTrackingContainers()
1943 // Building tracking containers for clusters
1945 Int_t nin =0, icl = fClusters->GetEntriesFast();
1947 AliTRDcluster *c = (AliTRDcluster *) fClusters->UncheckedAt(icl);
1948 if(c->IsInChamber()) nin++;
1949 if(fkReconstructor->IsHLT()) c->SetRPhiMethod(AliTRDcluster::kCOG);
1950 Int_t detector = c->GetDetector();
1951 Int_t sector = fGeom->GetSector(detector);
1952 Int_t stack = fGeom->GetStack(detector);
1953 Int_t layer = fGeom->GetLayer(detector);
1955 fTrSec[sector].GetChamber(stack, layer, kTRUE)->InsertCluster(c, icl);
1958 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
1959 for(int isector =0; isector<AliTRDgeometry::kNsector; isector++){
1960 if(!fTrSec[isector].GetNChambers()) continue;
1961 fTrSec[isector].Init(fkReconstructor, cal);
1969 //____________________________________________________________________
1970 void AliTRDtrackerV1::UnloadClusters()
1973 // Clears the arrays of clusters and tracks. Resets sectors and timebins
1974 // If option "force" is also set the containers are also deleted. This is useful
1979 if(HasRemoveContainers()){delete fTracks; fTracks = NULL;}
1982 fTracklets->Delete();
1983 if(HasRemoveContainers()){delete fTracklets; fTracklets = NULL;}
1986 if(IsClustersOwner()) fClusters->Delete();
1988 // save clusters array in the reconstructor for further use.
1989 if(!fkReconstructor->IsWritingClusters()){
1990 AliTRDReconstructor::SetClusters(fClusters);
1991 SetClustersOwner(kFALSE);
1992 } else AliTRDReconstructor::SetClusters(NULL);
1995 for (int i = 0; i < AliTRDgeometry::kNsector; i++) fTrSec[i].Clear();
1997 // Increment the Event Number
1998 AliTRDtrackerDebug::SetEventNumber(AliTRDtrackerDebug::GetEventNumber() + 1);
2001 // //____________________________________________________________________
2002 // void AliTRDtrackerV1::UseClusters(const AliKalmanTrack *t, Int_t) const
2004 // const AliTRDtrackV1 *track = dynamic_cast<const AliTRDtrackV1*>(t);
2005 // if(!track) return;
2007 // AliTRDseedV1 *tracklet = NULL;
2008 // for(Int_t ily=AliTRDgeometry::kNlayer; ily--;){
2009 // if(!(tracklet = track->GetTracklet(ily))) continue;
2010 // AliTRDcluster *c = NULL;
2011 // for(Int_t ic=AliTRDseed::kNclusters; ic--;){
2012 // if(!(c=tracklet->GetClusters(ic))) continue;
2019 //_____________________________________________________________________________
2020 Bool_t AliTRDtrackerV1::AdjustSector(AliTRDtrackV1 *const track)
2023 // Rotates the track when necessary
2026 Double_t alpha = AliTRDgeometry::GetAlpha();
2027 Double_t y = track->GetY();
2028 Double_t ymax = track->GetX()*TMath::Tan(0.5*alpha);
2031 if (!track->Rotate( alpha)) {
2035 else if (y < -ymax) {
2036 if (!track->Rotate(-alpha)) {
2046 //____________________________________________________________________
2047 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(AliTRDtrackV1 *const track, Int_t p, Int_t &idx)
2049 // Find tracklet for TRD track <track>
2058 // Detailed description
2060 idx = track->GetTrackletIndex(p);
2061 AliTRDseedV1 *tracklet = (idx<0) ? NULL : (AliTRDseedV1*)fTracklets->UncheckedAt(idx);
2066 //____________________________________________________________________
2067 AliTRDseedV1* AliTRDtrackerV1::SetTracklet(const AliTRDseedV1 * const tracklet)
2069 // Add this tracklet to the list of tracklets stored in the tracker
2072 // - tracklet : pointer to the tracklet to be added to the list
2075 // - the index of the new tracklet in the tracker tracklets list
2077 // Detailed description
2078 // Build the tracklets list if it is not yet created (late initialization)
2079 // and adds the new tracklet to the list.
2082 fTracklets = new TClonesArray("AliTRDseedV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2083 fTracklets->SetOwner(kTRUE);
2085 Int_t nentries = fTracklets->GetEntriesFast();
2086 return new ((*fTracklets)[nentries]) AliTRDseedV1(*tracklet);
2089 //____________________________________________________________________
2090 AliTRDtrackV1* AliTRDtrackerV1::SetTrack(const AliTRDtrackV1 * const track)
2092 // Add this track to the list of tracks stored in the tracker
2095 // - track : pointer to the track to be added to the list
2098 // - the pointer added
2100 // Detailed description
2101 // Build the tracks list if it is not yet created (late initialization)
2102 // and adds the new track to the list.
2105 fTracks = new TClonesArray("AliTRDtrackV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2106 fTracks->SetOwner(kTRUE);
2108 Int_t nentries = fTracks->GetEntriesFast();
2109 return new ((*fTracks)[nentries]) AliTRDtrackV1(*track);
2114 //____________________________________________________________________
2115 Int_t AliTRDtrackerV1::Clusters2TracksSM(Int_t sector, AliESDEvent *esd)
2118 // Steer tracking for one SM.
2121 // sector : Array of (SM) propagation layers containing clusters
2122 // esd : The current ESD event. On output it contains the also
2123 // the ESD (TRD) tracks found in this SM.
2126 // Number of tracks found in this TRD supermodule.
2128 // Detailed description
2130 // 1. Unpack AliTRDpropagationLayers objects for each stack.
2131 // 2. Launch stack tracking.
2132 // See AliTRDtrackerV1::Clusters2TracksStack() for details.
2133 // 3. Pack results in the ESD event.
2137 Int_t nChambers = 0;
2138 AliTRDtrackingChamber **stack = NULL, *chamber = NULL;
2139 for(int istack = 0; istack<AliTRDgeometry::kNstack; istack++){
2140 if(!(stack = fTrSec[sector].GetStack(istack))) continue;
2142 for(int ilayer=0; ilayer<AliTRDgeometry::kNlayer; ilayer++){
2143 if(!(chamber = stack[ilayer])) continue;
2144 if(chamber->GetNClusters() < fgNTimeBins * fkRecoParam->GetFindableClusters()) continue;
2146 //AliInfo(Form("sector %d stack %d layer %d clusters %d", sector, istack, ilayer, chamber->GetNClusters()));
2148 if(nChambers < 4) continue;
2149 //AliInfo(Form("Doing stack %d", istack));
2150 nTracks += Clusters2TracksStack(stack, fTracksESD);
2152 if(nTracks) AliDebug(2, Form("Number of tracks: SM_%02d[%d]", sector, nTracks));
2154 for(int itrack=0; itrack<nTracks; itrack++){
2155 AliESDtrack *esdTrack((AliESDtrack*)(fTracksESD->operator[](itrack)));
2156 Int_t id = esd->AddTrack(esdTrack);
2158 // set ESD id to stand alone TRD tracks
2159 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2160 esdTrack=esd->GetTrack(id);
2161 TObject *o(NULL); Int_t ic(0);
2162 AliTRDtrackV1 *calibTrack(NULL);
2163 while((o = esdTrack->GetCalibObject(ic++))){
2164 if(!(calibTrack = dynamic_cast<AliTRDtrackV1*>(o))) continue;
2165 calibTrack->SetESDid(esdTrack->GetID());
2171 // Reset Track and Candidate Number
2172 AliTRDtrackerDebug::SetCandidateNumber(0);
2173 AliTRDtrackerDebug::SetTrackNumber(0);
2175 // delete ESD tracks in the array
2176 fTracksESD->Delete();
2180 //____________________________________________________________________
2181 Int_t AliTRDtrackerV1::Clusters2TracksStack(AliTRDtrackingChamber **stack, TClonesArray * const esdTrackList)
2184 // Make tracks in one TRD stack.
2187 // layer : Array of stack propagation layers containing clusters
2188 // esdTrackList : Array of ESD tracks found by the stand alone tracker.
2189 // On exit the tracks found in this stack are appended.
2192 // Number of tracks found in this stack.
2194 // Detailed description
2196 // 1. Find the 3 most useful seeding chambers. See BuildSeedingConfigs() for details.
2197 // 2. Steer AliTRDtrackerV1::MakeSeeds() for 3 seeding layer configurations.
2198 // See AliTRDtrackerV1::MakeSeeds() for more details.
2199 // 3. Arrange track candidates in decreasing order of their quality
2200 // 4. Classify tracks in 5 categories according to:
2201 // a) number of layers crossed
2203 // 5. Sign clusters by tracks in decreasing order of track quality
2204 // 6. Build AliTRDtrack out of seeding tracklets
2206 // 8. Build ESD track and register it to the output list
2209 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
2210 AliTRDtrackingChamber *chamber = NULL;
2211 AliTRDtrackingChamber **ci = NULL;
2212 AliTRDseedV1 sseed[kMaxTracksStack*6]; // to be initialized
2213 Int_t pars[4]; // MakeSeeds parameters
2215 //Double_t alpha = AliTRDgeometry::GetAlpha();
2216 //Double_t shift = .5 * alpha;
2217 Int_t configs[kNConfigs];
2219 // Purge used clusters from the containers
2221 for(Int_t ic = kNPlanes; ic--; ci++){
2222 if(!(*ci)) continue;
2226 // Build initial seeding configurations
2227 Double_t quality = BuildSeedingConfigs(stack, configs);
2228 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2229 AliInfo(Form("Plane config %d %d %d Quality %f"
2230 , configs[0], configs[1], configs[2], quality));
2234 // Initialize contors
2235 Int_t ntracks, // number of TRD track candidates
2236 ntracks1, // number of registered TRD tracks/iter
2237 ntracks2 = 0; // number of all registered TRD tracks in stack
2241 Int_t ic = 0; ci = &stack[0];
2242 while(ic<kNPlanes && !(*ci)){ic++; ci++;}
2243 if(!(*ci)) return ntracks2;
2244 Int_t istack = fGeom->GetStack((*ci)->GetDetector());
2247 // Loop over seeding configurations
2248 ntracks = 0; ntracks1 = 0;
2249 for (Int_t iconf = 0; iconf<3; iconf++) {
2250 pars[0] = configs[iconf];
2253 ntracks = MakeSeeds(stack, &sseed[6*ntracks], pars);
2254 //AliInfo(Form("Number of Tracks after iteration step %d: %d\n", iconf, ntracks));
2255 if(ntracks == kMaxTracksStack) break;
2257 AliDebug(2, Form("Candidate TRD tracks %d in iteration %d.", ntracks, fSieveSeeding));
2261 // Sort the seeds according to their quality
2262 Int_t sort[kMaxTracksStack];
2263 TMath::Sort(ntracks, fTrackQuality, sort, kTRUE);
2265 // Initialize number of tracks so far and logic switches
2266 Int_t ntracks0 = esdTrackList->GetEntriesFast();
2267 Bool_t signedTrack[kMaxTracksStack];
2268 Bool_t fakeTrack[kMaxTracksStack];
2269 for (Int_t i=0; i<ntracks; i++){
2270 signedTrack[i] = kFALSE;
2271 fakeTrack[i] = kFALSE;
2273 //AliInfo("Selecting track candidates ...");
2275 // Sieve clusters in decreasing order of track quality
2276 Double_t trackParams[7];
2277 // AliTRDseedV1 *lseed = NULL;
2278 Int_t jSieve = 0, candidates;
2280 //AliInfo(Form("\t\tITER = %i ", jSieve));
2282 // Check track candidates
2284 for (Int_t itrack = 0; itrack < ntracks; itrack++) {
2285 Int_t trackIndex = sort[itrack];
2286 if (signedTrack[trackIndex] || fakeTrack[trackIndex]) continue;
2289 // Calculate track parameters from tracklets seeds
2294 for (Int_t jLayer = 0; jLayer < kNPlanes; jLayer++) {
2295 Int_t jseed = kNPlanes*trackIndex+jLayer;
2296 if(!sseed[jseed].IsOK()) continue;
2297 if (TMath::Abs(sseed[jseed].GetYref(0) / sseed[jseed].GetX0()) < 0.158) findable++;
2298 // TODO here we get a sig fault which should never happen !
2299 sseed[jseed].UpdateUsed();
2300 ncl += sseed[jseed].GetN2();
2301 nused += sseed[jseed].GetNUsed();
2305 // Filter duplicated tracks
2307 //printf("Skip %d nused %d\n", trackIndex, nused);
2308 fakeTrack[trackIndex] = kTRUE;
2311 if (ncl>0 && Float_t(nused)/ncl >= .25){
2312 //printf("Skip %d nused/ncl >= .25\n", trackIndex);
2313 fakeTrack[trackIndex] = kTRUE;
2318 Bool_t skip = kFALSE;
2321 if(nlayers < 6) {skip = kTRUE; break;}
2322 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2326 if(nlayers < findable){skip = kTRUE; break;}
2327 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -4.){skip = kTRUE; break;}
2331 if ((nlayers == findable) || (nlayers == 6)) { skip = kTRUE; break;}
2332 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -6.0){skip = kTRUE; break;}
2336 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2340 if (nlayers == 3){skip = kTRUE; break;}
2341 //if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) - nused/(nlayers-3.0) < -15.0){skip = kTRUE; break;}
2346 AliDebug(4, Form("REJECTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2348 } else AliDebug(4, Form("ACCEPTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2350 signedTrack[trackIndex] = kTRUE;
2352 // Build track parameters
2353 AliTRDseedV1 *lseed =&sseed[trackIndex*6];
2355 while(idx<3 && !lseed->IsOK()) {
2359 Double_t x = lseed->GetX0();// - 3.5;
2360 trackParams[0] = x; //NEW AB
2361 trackParams[1] = lseed->GetYref(0); // lseed->GetYat(x);
2362 trackParams[2] = lseed->GetZref(0); // lseed->GetZat(x);
2363 trackParams[3] = TMath::Sin(TMath::ATan(lseed->GetYref(1)));
2364 trackParams[4] = lseed->GetZref(1) / TMath::Sqrt(1. + lseed->GetYref(1) * lseed->GetYref(1));
2365 trackParams[5] = lseed->GetC();
2366 Int_t ich = 0; while(!(chamber = stack[ich])) ich++;
2367 trackParams[6] = fGeom->GetSector(chamber->GetDetector());/* *alpha+shift; // Supermodule*/
2369 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 1 && fkReconstructor->IsDebugStreaming()){
2370 //AliInfo(Form("Track %d [%d] nlayers %d trackQuality = %e nused %d, yref = %3.3f", itrack, trackIndex, nlayers, fTrackQuality[trackIndex], nused, trackParams[1]));
2372 AliTRDseedV1 *dseed[6];
2373 for(Int_t iseed = AliTRDgeometry::kNlayer; iseed--;) dseed[iseed] = new AliTRDseedV1(lseed[iseed]);
2375 //Int_t eventNrInFile = esd->GetEventNumberInFile();
2376 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2377 Int_t trackNumber = AliTRDtrackerDebug::GetTrackNumber();
2378 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2379 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2380 cstreamer << "Clusters2TracksStack"
2381 << "EventNumber=" << eventNumber
2382 << "TrackNumber=" << trackNumber
2383 << "CandidateNumber=" << candidateNumber
2384 << "Iter=" << fSieveSeeding
2385 << "Like=" << fTrackQuality[trackIndex]
2386 << "S0.=" << dseed[0]
2387 << "S1.=" << dseed[1]
2388 << "S2.=" << dseed[2]
2389 << "S3.=" << dseed[3]
2390 << "S4.=" << dseed[4]
2391 << "S5.=" << dseed[5]
2392 << "p0=" << trackParams[0]
2393 << "p1=" << trackParams[1]
2394 << "p2=" << trackParams[2]
2395 << "p3=" << trackParams[3]
2396 << "p4=" << trackParams[4]
2397 << "p5=" << trackParams[5]
2398 << "p6=" << trackParams[6]
2400 << "NLayers=" << nlayers
2401 << "Findable=" << findable
2402 << "NUsed=" << nused
2406 AliTRDtrackV1 *track = MakeTrack(&sseed[trackIndex*kNPlanes], trackParams);
2408 AliDebug(1, "Track building failed.");
2412 //AliInfo("End of MakeTrack()");
2413 AliESDtrack *esdTrack = new ((*esdTrackList)[ntracks0++]) AliESDtrack();
2414 esdTrack->UpdateTrackParams(track, AliESDtrack::kTRDout);
2415 esdTrack->SetLabel(track->GetLabel());
2416 track->UpdateESDtrack(esdTrack);
2417 // write ESD-friends if neccessary
2418 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2419 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(*track);
2420 calibTrack->SetOwner();
2421 esdTrack->AddCalibObject(calibTrack);
2424 AliTRDtrackerDebug::SetTrackNumber(AliTRDtrackerDebug::GetTrackNumber() + 1);
2428 } while(jSieve<5 && candidates); // end track candidates sieve
2429 if(!ntracks1) break;
2431 // increment counters
2432 ntracks2 += ntracks1;
2434 if(fkReconstructor->IsHLT()) break;
2437 // Rebuild plane configurations and indices taking only unused clusters into account
2438 quality = BuildSeedingConfigs(stack, configs);
2439 if(quality < 1.E-7) break; //fkReconstructor->GetRecoParam() ->GetPlaneQualityThreshold()) break;
2441 for(Int_t ip = 0; ip < kNPlanes; ip++){
2442 if(!(chamber = stack[ip])) continue;
2443 chamber->Build(fGeom, cal);//Indices(fSieveSeeding);
2446 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2447 AliInfo(Form("Sieve level %d Plane config %d %d %d Quality %f", fSieveSeeding, configs[0], configs[1], configs[2], quality));
2449 } while(fSieveSeeding<10); // end stack clusters sieve
2453 //AliInfo(Form("Registered TRD tracks %d in stack %d.", ntracks2, pars[1]));
2458 //___________________________________________________________________
2459 Double_t AliTRDtrackerV1::BuildSeedingConfigs(AliTRDtrackingChamber **stack, Int_t *configs)
2462 // Assign probabilities to chambers according to their
2463 // capability of producing seeds.
2467 // layers : Array of stack propagation layers for all 6 chambers in one stack
2468 // configs : On exit array of configuration indexes (see GetSeedingConfig()
2469 // for details) in the decreasing order of their seeding probabilities.
2473 // Return top configuration quality
2475 // Detailed description:
2477 // To each chamber seeding configuration (see GetSeedingConfig() for
2478 // the list of all configurations) one defines 2 quality factors:
2479 // - an apriori topological quality (see GetSeedingConfig() for details) and
2480 // - a data quality based on the uniformity of the distribution of
2481 // clusters over the x range (time bins population). See CookChamberQA() for details.
2482 // The overall chamber quality is given by the product of this 2 contributions.
2485 Double_t chamberQ[kNPlanes];memset(chamberQ, 0, kNPlanes*sizeof(Double_t));
2486 AliTRDtrackingChamber *chamber = NULL;
2487 for(int iplane=0; iplane<kNPlanes; iplane++){
2488 if(!(chamber = stack[iplane])) continue;
2489 chamberQ[iplane] = (chamber = stack[iplane]) ? chamber->GetQuality() : 0.;
2492 Double_t tconfig[kNConfigs];memset(tconfig, 0, kNConfigs*sizeof(Double_t));
2493 Int_t planes[] = {0, 0, 0, 0};
2494 for(int iconf=0; iconf<kNConfigs; iconf++){
2495 GetSeedingConfig(iconf, planes);
2496 tconfig[iconf] = fgTopologicQA[iconf];
2497 for(int iplane=0; iplane<4; iplane++) tconfig[iconf] *= chamberQ[planes[iplane]];
2500 TMath::Sort((Int_t)kNConfigs, tconfig, configs, kTRUE);
2501 // AliInfo(Form("q[%d] = %f", configs[0], tconfig[configs[0]]));
2502 // AliInfo(Form("q[%d] = %f", configs[1], tconfig[configs[1]]));
2503 // AliInfo(Form("q[%d] = %f", configs[2], tconfig[configs[2]]));
2505 return tconfig[configs[0]];
2508 //____________________________________________________________________
2509 Int_t AliTRDtrackerV1::MakeSeeds(AliTRDtrackingChamber **stack, AliTRDseedV1 * const sseed, const Int_t * const ipar)
2512 // Seed tracklets and build candidate TRD tracks. The procedure is used during barrel tracking to account for tracks which are
2513 // either missed by TPC prolongation or conversions inside the TRD volume.
2514 // For stand alone tracking the procedure is used to estimate all tracks measured by TRD.
2517 // layers : Array of stack propagation layers containing clusters
2518 // sseed : Array of empty tracklet seeds. On exit they are filled.
2519 // ipar : Control parameters:
2520 // ipar[0] -> seeding chambers configuration
2521 // ipar[1] -> stack index
2522 // ipar[2] -> number of track candidates found so far
2525 // Number of tracks candidates found.
2527 // The following steps are performed:
2528 // 1. Build seeding layers by collapsing all time bins from each of the four seeding chambers along the
2529 // radial coordinate. See AliTRDtrackingChamber::GetSeedingLayer() for details. The chambers selection for seeding
2530 // is described in AliTRDtrackerV1::Clusters2TracksStack().
2531 // 2. Using the seeding clusters from the seeding layer (step 1) build combinatorics using the following algorithm:
2532 // - for each seeding cluster in the lower seeding layer find
2533 // - all seeding clusters in the upper seeding layer inside a road defined by a given phi angle. The angle
2534 // is calculated on the minimum pt of tracks from vertex accesible to the stand alone tracker.
2535 // - for each pair of two extreme seeding clusters select middle upper cluster using roads defined externally by the
2537 // - select last seeding cluster as the nearest to the linear approximation of the track described by the first three
2538 // seeding clusters.
2539 // The implementation of road calculation and cluster selection can be found in the functions AliTRDchamberTimeBin::BuildCond()
2540 // and AliTRDchamberTimeBin::GetClusters().
2541 // 3. Helix fit of the seeding clusters set. (see AliTRDtrackerFitter::FitRieman(AliTRDcluster**)). No tilt correction is
2542 // performed at this level
2543 // 4. Initialize seeding tracklets in the seeding chambers.
2544 // 5. *Filter 0* Chi2 cut on the Y and Z directions. The threshold is set externally by the reco params.
2545 // 6. Attach (true) clusters to seeding tracklets (see AliTRDseedV1::AttachClusters()) and fit tracklet (see
2546 // AliTRDseedV1::Fit()). The number of used clusters used by current seeds should not exceed ... (25).
2547 // 7. *Filter 1* Check if all 4 seeding tracklets are correctly constructed.
2548 // 8. Helix fit of the clusters from the seeding tracklets with tilt correction. Refit tracklets using the new
2549 // approximation of the track.
2550 // 9. *Filter 2* Calculate likelihood of the track. (See AliTRDtrackerV1::CookLikelihood()). The following quantities are
2551 // checked against the Riemann fit:
2552 // - position resolution in y
2553 // - angular resolution in the bending plane
2554 // - likelihood of the number of clusters attached to the tracklet
2555 // 10. Extrapolation of the helix fit to the other 2 chambers *non seeding* chambers:
2556 // - Initialization of extrapolation tracklets with the fit parameters
2557 // - Attach clusters to extrapolated tracklets
2558 // - Helix fit of tracklets
2559 // 11. Improve seeding tracklets quality by reassigning clusters based on the last parameters of the track
2560 // See AliTRDtrackerV1::ImproveSeedQuality() for details.
2561 // 12. Helix fit of all 6 seeding tracklets and chi2 calculation
2562 // 13. Hyperplane fit and track quality calculation. See AliTRDtrackerFitter::FitHyperplane() for details.
2563 // 14. Cooking labels for tracklets. Should be done only for MC
2564 // 15. Register seeds.
2567 // Marian Ivanov <M.Ivanov@gsi.de>
2568 // Alexandru Bercuci <A.Bercuci@gsi.de>
2569 // Markus Fasel <M.Fasel@gsi.de>
2571 AliTRDtrackingChamber *chamber = NULL;
2572 AliTRDcluster *c[kNSeedPlanes] = {NULL, NULL, NULL, NULL}; // initilize seeding clusters
2573 AliTRDseedV1 *cseed = &sseed[0]; // initialize tracklets for first track
2574 Int_t ncl, mcl; // working variable for looping over clusters
2575 Int_t index[AliTRDchamberTimeBin::kMaxClustersLayer], jndex[AliTRDchamberTimeBin::kMaxClustersLayer];
2577 // chi2[0] = tracklet chi2 on the Z direction
2578 // chi2[1] = tracklet chi2 on the R direction
2581 // this should be data member of AliTRDtrack TODO
2582 Double_t seedQuality[kMaxTracksStack];
2584 // unpack control parameters
2585 Int_t config = ipar[0];
2586 Int_t ntracks = ipar[1];
2587 Int_t istack = ipar[2];
2588 Int_t planes[kNSeedPlanes]; GetSeedingConfig(config, planes);
2589 Int_t planesExt[kNPlanes-kNSeedPlanes]; GetExtrapolationConfig(config, planesExt);
2592 // Init chambers geometry
2593 Double_t hL[kNPlanes]; // Tilting angle
2594 Float_t padlength[kNPlanes]; // pad lenghts
2595 Float_t padwidth[kNPlanes]; // pad widths
2596 AliTRDpadPlane *pp = NULL;
2597 for(int iplane=0; iplane<kNPlanes; iplane++){
2598 pp = fGeom->GetPadPlane(iplane, istack);
2599 hL[iplane] = TMath::Tan(TMath::DegToRad()*pp->GetTiltingAngle());
2600 padlength[iplane] = pp->GetLengthIPad();
2601 padwidth[iplane] = pp->GetWidthIPad();
2604 // Init anode wire position for chambers
2605 Double_t x0[kNPlanes], // anode wire position
2606 driftLength = .5*AliTRDgeometry::AmThick() - AliTRDgeometry::DrThick(); // drift length
2607 TGeoHMatrix *matrix = NULL;
2608 Double_t loc[] = {AliTRDgeometry::AnodePos(), 0., 0.};
2609 Double_t glb[] = {0., 0., 0.};
2610 AliTRDtrackingChamber **cIter = &stack[0];
2611 for(int iLayer=0; iLayer<kNPlanes; iLayer++,cIter++){
2612 if(!(*cIter)) continue;
2613 if(!(matrix = fGeom->GetClusterMatrix((*cIter)->GetDetector()))){
2615 x0[iLayer] = fgkX0[iLayer];
2617 matrix->LocalToMaster(loc, glb);
2618 x0[iLayer] = glb[0];
2621 AliDebug(2, Form("Making seeds Stack[%d] Config[%d] Tracks[%d]...", istack, config, ntracks));
2623 // Build seeding layers
2626 for(int isl=0; isl<kNSeedPlanes; isl++){
2627 if(!(chamber = stack[planes[isl]])) continue;
2628 if(!chamber->GetSeedingLayer(fSeedTB[isl], fGeom, fkReconstructor)) continue;
2631 if(nlayers < kNSeedPlanes) return ntracks;
2634 // Start finding seeds
2635 Double_t cond0[4], cond1[4], cond2[4];
2637 while((c[3] = (*fSeedTB[3])[icl++])){
2639 fSeedTB[0]->BuildCond(c[3], cond0, 0);
2640 fSeedTB[0]->GetClusters(cond0, index, ncl);
2641 //printf("Found c[3] candidates 0 %d\n", ncl);
2644 c[0] = (*fSeedTB[0])[index[jcl++]];
2646 Double_t dx = c[3]->GetX() - c[0]->GetX();
2647 Double_t dzdx = (c[3]->GetZ() - c[0]->GetZ())/dx;
2648 Double_t dydx = (c[3]->GetY() - c[0]->GetY())/dx;
2649 fSeedTB[1]->BuildCond(c[0], cond1, 1, dzdx, dydx);
2650 fSeedTB[1]->GetClusters(cond1, jndex, mcl);
2651 //printf("Found c[0] candidates 1 %d\n", mcl);
2655 c[1] = (*fSeedTB[1])[jndex[kcl++]];
2657 fSeedTB[2]->BuildCond(c[1], cond2, 2, dzdx, dydx);
2658 c[2] = fSeedTB[2]->GetNearestCluster(cond2);
2659 //printf("Found c[1] candidate 2 %p\n", c[2]);
2662 AliDebug(3, Form("Seeding clusters\n 0[%6.3f %6.3f %6.3f]\n 1[%6.3f %6.3f %6.3f]\n 2[%6.3f %6.3f %6.3f]\n 3[%6.3f %6.3f %6.3f].",
2663 c[0]->GetX(), c[0]->GetY(), c[0]->GetZ(),
2664 c[1]->GetX(), c[1]->GetY(), c[1]->GetZ(),
2665 c[2]->GetX(), c[2]->GetY(), c[2]->GetZ(),
2666 c[3]->GetX(), c[3]->GetY(), c[3]->GetZ()));
2668 for (Int_t il = 0; il < kNPlanes; il++) cseed[il].Reset();
2672 AliTRDseedV1 *tseed = &cseed[0];
2674 for(int iLayer=0; iLayer<kNPlanes; iLayer++, tseed++, cIter++){
2675 Int_t det = (*cIter) ? (*cIter)->GetDetector() : -1;
2676 tseed->SetDetector(det);
2677 tseed->SetTilt(hL[iLayer]);
2678 tseed->SetPadLength(padlength[iLayer]);
2679 tseed->SetPadWidth(padwidth[iLayer]);
2680 tseed->SetReconstructor(fkReconstructor);
2681 tseed->SetX0(det<0 ? fR[iLayer]+driftLength : x0[iLayer]);
2682 tseed->Init(GetRiemanFitter());
2683 tseed->SetStandAlone(kTRUE);
2686 Bool_t isFake = kFALSE;
2687 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2688 if (c[0]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2689 if (c[1]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2690 if (c[2]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2693 for(Int_t l = 0; l < kNSeedPlanes; l++) xpos[l] = fSeedTB[l]->GetX();
2695 for(int il=0; il<4; il++) yref[il] = cseed[planes[il]].GetYref(0);
2696 Int_t ll = c[3]->GetLabel(0);
2697 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2698 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2699 AliRieman *rim = GetRiemanFitter();
2700 TTreeSRedirector &cs0 = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2702 <<"EventNumber=" << eventNumber
2703 <<"CandidateNumber=" << candidateNumber
2704 <<"isFake=" << isFake
2705 <<"config=" << config
2707 <<"chi2z=" << chi2[0]
2708 <<"chi2y=" << chi2[1]
2709 <<"Y2exp=" << cond2[0]
2710 <<"Z2exp=" << cond2[1]
2711 <<"X0=" << xpos[0] //layer[sLayer]->GetX()
2712 <<"X1=" << xpos[1] //layer[sLayer + 1]->GetX()
2713 <<"X2=" << xpos[2] //layer[sLayer + 2]->GetX()
2714 <<"X3=" << xpos[3] //layer[sLayer + 3]->GetX()
2715 <<"yref0=" << yref[0]
2716 <<"yref1=" << yref[1]
2717 <<"yref2=" << yref[2]
2718 <<"yref3=" << yref[3]
2723 <<"Seed0.=" << &cseed[planes[0]]
2724 <<"Seed1.=" << &cseed[planes[1]]
2725 <<"Seed2.=" << &cseed[planes[2]]
2726 <<"Seed3.=" << &cseed[planes[3]]
2727 <<"RiemanFitter.=" << rim
2730 if(chi2[0] > fkRecoParam->GetChi2Z()/*7./(3. - sLayer)*//*iter*/){
2731 AliDebug(3, Form("Filter on chi2Z [%f].", chi2[0]));
2732 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2735 if(chi2[1] > fkRecoParam->GetChi2Y()/*1./(3. - sLayer)*//*iter*/){
2736 AliDebug(3, Form("Filter on chi2Y [%f].", chi2[1]));
2737 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2740 //AliInfo("Passed chi2 filter.");
2742 // try attaching clusters to tracklets
2744 AliTRDcluster *cl = NULL;
2745 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2746 Int_t jLayer = planes[iLayer];
2747 Int_t nNotInChamber = 0;
2748 if(!cseed[jLayer].AttachClusters(stack[jLayer], kTRUE)) continue;
2749 if(/*fkReconstructor->IsHLT()*/kFALSE){
2750 cseed[jLayer].UpdateUsed();
2751 if(!cseed[jLayer].IsOK()) continue;
2753 cseed[jLayer].Fit();
2754 cseed[jLayer].UpdateUsed();
2755 cseed[jLayer].ResetClusterIter();
2756 while((cl = cseed[jLayer].NextCluster())){
2757 if(!cl->IsInChamber()) nNotInChamber++;
2759 //printf("clusters[%d], used[%d], not in chamber[%d]\n", cseed[jLayer].GetN(), cseed[jLayer].GetNUsed(), nNotInChamber);
2760 if(cseed[jLayer].GetN() - (cseed[jLayer].GetNUsed() + nNotInChamber) < 5) continue; // checking for Cluster which are not in chamber is a much stronger restriction on real data
2765 if(mlayers < kNSeedPlanes){
2766 AliDebug(2, Form("Found only %d tracklets out of %d. Skip.", mlayers, kNSeedPlanes));
2767 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2771 // temporary exit door for the HLT
2772 if(fkReconstructor->IsHLT()){
2773 // attach clusters to extrapolation chambers
2774 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2775 Int_t jLayer = planesExt[iLayer];
2776 if(!(chamber = stack[jLayer])) continue;
2777 if(!cseed[jLayer].AttachClusters(chamber, kTRUE)) continue;
2778 cseed[jLayer].Fit();
2780 fTrackQuality[ntracks] = 1.; // dummy value
2782 if(ntracks == kMaxTracksStack) return ntracks;
2788 // Update Seeds and calculate Likelihood
2789 // fit tracklets and cook likelihood
2790 FitTiltedRieman(&cseed[0], kTRUE);
2791 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2792 Int_t jLayer = planes[iLayer];
2793 cseed[jLayer].Fit(kTRUE);
2795 Double_t like = CookLikelihood(&cseed[0], planes); // to be checked
2797 if (TMath::Log(1.E-9 + like) < fkRecoParam->GetTrackLikelihood()){
2798 AliDebug(3, Form("Filter on likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2799 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2802 //AliInfo(Form("Passed likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2804 // book preliminary results
2805 seedQuality[ntracks] = like;
2806 fSeedLayer[ntracks] = config;/*sLayer;*/
2808 // attach clusters to the extrapolation seeds
2810 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2811 Int_t jLayer = planesExt[iLayer];
2812 if(!(chamber = stack[jLayer])) continue;
2814 // fit extrapolated seed
2815 if ((jLayer == 0) && !(cseed[1].IsOK())) continue;
2816 if ((jLayer == 5) && !(cseed[4].IsOK())) continue;
2817 AliTRDseedV1 pseed = cseed[jLayer];
2818 if(!pseed.AttachClusters(chamber, kTRUE)) continue;
2820 cseed[jLayer] = pseed;
2821 FitTiltedRieman(cseed, kTRUE);
2822 cseed[jLayer].Fit(kTRUE);
2826 // AliInfo("Extrapolation done.");
2827 // Debug Stream containing all the 6 tracklets
2828 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2829 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2830 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
2831 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2832 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2833 cstreamer << "MakeSeeds1"
2834 << "EventNumber=" << eventNumber
2835 << "CandidateNumber=" << candidateNumber
2836 << "S0.=" << &cseed[0]
2837 << "S1.=" << &cseed[1]
2838 << "S2.=" << &cseed[2]
2839 << "S3.=" << &cseed[3]
2840 << "S4.=" << &cseed[4]
2841 << "S5.=" << &cseed[5]
2842 << "FitterT.=" << tiltedRieman
2846 if(fkRecoParam->HasImproveTracklets()){
2847 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
2848 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer] = cseed[jLayer];
2850 if(ImproveSeedQuality(stack, cseed) < mlayers+elayers){
2851 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2852 AliDebug(3, "Filter on improve seeds.");
2855 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) cseed[jLayer] = bseed[jLayer];
2858 //AliInfo("Improve seed quality done.");
2860 // fit full track and cook likelihoods
2861 // Double_t curv = FitRieman(&cseed[0], chi2);
2862 // Double_t chi2ZF = chi2[0] / TMath::Max((mlayers - 3.), 1.);
2863 // Double_t chi2RF = chi2[1] / TMath::Max((mlayers - 3.), 1.);
2865 // do the final track fitting (Once with vertex constraint and once without vertex constraint)
2866 Double_t chi2Vals[3];
2867 chi2Vals[0] = FitTiltedRieman(&cseed[0], kTRUE);
2868 if(fkRecoParam->IsVertexConstrained())
2869 chi2Vals[1] = FitTiltedRiemanConstraint(&cseed[0], GetZ()); // Do Vertex Constrained fit if desired
2872 chi2Vals[2] = GetChi2Z(&cseed[0]) / TMath::Max((mlayers - 3.), 1.);
2873 // Chi2 definitions in testing stage
2874 //chi2Vals[2] = GetChi2ZTest(&cseed[0]);
2875 fTrackQuality[ntracks] = CalculateTrackLikelihood(&cseed[0], &chi2Vals[0]);
2876 //AliInfo("Hyperplane fit done\n");
2878 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2879 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2880 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2881 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2882 TLinearFitter *fitterTC = GetTiltedRiemanFitterConstraint();
2883 TLinearFitter *fitterT = GetTiltedRiemanFitter();
2885 for(Int_t iseed = 0; iseed < kNPlanes; iseed++){
2886 ncls += cseed[iseed].IsOK() ? cseed[iseed].GetN2() : 0;
2888 cstreamer << "MakeSeeds2"
2889 << "EventNumber=" << eventNumber
2890 << "CandidateNumber=" << candidateNumber
2891 << "Chi2TR=" << chi2Vals[0]
2892 << "Chi2TC=" << chi2Vals[1]
2893 << "Nlayers=" << mlayers
2894 << "NClusters=" << ncls
2896 << "S0.=" << &cseed[0]
2897 << "S1.=" << &cseed[1]
2898 << "S2.=" << &cseed[2]
2899 << "S3.=" << &cseed[3]
2900 << "S4.=" << &cseed[4]
2901 << "S5.=" << &cseed[5]
2902 << "FitterT.=" << fitterT
2903 << "FitterTC.=" << fitterTC
2908 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2909 if(ntracks == kMaxTracksStack){
2910 AliWarning(Form("Number of seeds reached maximum allowed (%d) in stack.", kMaxTracksStack));
2921 //_____________________________________________________________________________
2922 AliTRDtrackV1* AliTRDtrackerV1::MakeTrack(AliTRDseedV1 * const seeds, Double_t *params)
2925 // Build a TRD track out of tracklet candidates
2928 // seeds : array of tracklets
2929 // params : array of track parameters as they are estimated by stand alone tracker. 7 elements.
2930 // [0] - radial position of the track at reference point
2931 // [1] - y position of the fit at [0]
2932 // [2] - z position of the fit at [0]
2933 // [3] - snp of the first tracklet
2934 // [4] - tgl of the first tracklet
2935 // [5] - curvature of the Riemann fit - 1/pt
2936 // [6] - sector rotation angle
2941 // Initialize the TRD track based on the parameters of the fit and a parametric covariance matrix
2942 // (diagonal with constant variance terms TODO - correct parameterization)
2944 // In case of HLT just register the tracklets in the tracker and return values of the Riemann fit. For the
2945 // offline case perform a full Kalman filter on the already found tracklets (see AliTRDtrackerV1::FollowBackProlongation()
2946 // for details). Do also MC label calculation and PID if propagation successfully.
2949 Double_t alpha = AliTRDgeometry::GetAlpha();
2950 Double_t shift = AliTRDgeometry::GetAlpha()/2.0;
2953 c[ 0] = 0.2; // s^2_y
2954 c[ 1] = 0.0; c[ 2] = 2.0; // s^2_z
2955 c[ 3] = 0.0; c[ 4] = 0.0; c[ 5] = 0.02; // s^2_snp
2956 c[ 6] = 0.0; c[ 7] = 0.0; c[ 8] = 0.0; c[ 9] = 0.1; // s^2_tgl
2957 c[10] = 0.0; c[11] = 0.0; c[12] = 0.0; c[13] = 0.0; c[14] = params[5]*params[5]*0.01; // s^2_1/pt
2959 AliTRDtrackV1 track(seeds, ¶ms[1], c, params[0], params[6]*alpha+shift);
2960 track.PropagateTo(params[0]-5.0);
2961 AliTRDseedV1 *ptrTracklet = NULL;
2963 // skip Kalman filter for HLT
2964 if(/*fkReconstructor->IsHLT()*/kFALSE){
2965 for (Int_t jLayer = 0; jLayer < AliTRDgeometry::kNlayer; jLayer++) {
2966 track.UnsetTracklet(jLayer);
2967 ptrTracklet = &seeds[jLayer];
2968 if(!ptrTracklet->IsOK()) continue;
2969 if(TMath::Abs(ptrTracklet->GetYref(1) - ptrTracklet->GetYfit(1)) >= .2) continue; // check this condition with Marian
2970 ptrTracklet = SetTracklet(ptrTracklet);
2971 ptrTracklet->UseClusters();
2972 track.SetTracklet(ptrTracklet, fTracklets->GetEntriesFast()-1);
2974 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
2975 ptrTrack->CookPID();
2976 ptrTrack->CookLabel(.9);
2977 ptrTrack->SetReconstructor(fkReconstructor);
2981 // prevent the error message in AliTracker::MeanMaterialBudget: "start point out of geometry"
2982 if(TMath::Abs(track.GetX()) + TMath::Abs(track.GetY()) + TMath::Abs(track.GetZ()) > 10000)
2985 track.ResetCovariance(1);
2986 Int_t nc = TMath::Abs(FollowBackProlongation(track));
2987 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 5 && fkReconstructor->IsDebugStreaming()){
2988 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2989 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2990 Double_t p[5]; // Track Params for the Debug Stream
2991 track.GetExternalParameters(params[0], p);
2992 TTreeSRedirector &cs = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2994 << "EventNumber=" << eventNumber
2995 << "CandidateNumber=" << candidateNumber
2997 << "X=" << params[0]
3003 << "Yin=" << params[1]
3004 << "Zin=" << params[2]
3005 << "snpin=" << params[3]
3006 << "tndin=" << params[4]
3007 << "crvin=" << params[5]
3008 << "track.=" << &track
3011 if (nc < 30) return NULL;
3013 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
3014 ptrTrack->SetReconstructor(fkReconstructor);
3015 ptrTrack->CookLabel(.9);
3017 // computes PID for track
3018 ptrTrack->CookPID();
3019 // update calibration references using this track
3020 AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance();
3022 AliInfo("Could not get Calibra instance\n");
3023 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(ptrTrack);
3029 //____________________________________________________________________
3030 Int_t AliTRDtrackerV1::ImproveSeedQuality(AliTRDtrackingChamber **stack, AliTRDseedV1 *cseed)
3033 // Sort tracklets according to "quality" and try to "improve" the first 4 worst
3036 // layers : Array of propagation layers for a stack/supermodule
3037 // cseed : Array of 6 seeding tracklets which has to be improved
3040 // cssed : Improved seeds
3042 // Detailed description
3044 // Iterative procedure in which new clusters are searched for each
3045 // tracklet seed such that the seed quality (see AliTRDseed::GetQuality())
3046 // can be maximized. If some optimization is found the old seeds are replaced.
3051 // make a local working copy
3052 AliTRDtrackingChamber *chamber = NULL;
3053 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
3055 Float_t quality(0.),
3056 lQuality[] = {1.e3, 1.e3, 1.e3, 1.e3, 1.e3, 1.e3};
3058 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;){
3059 bseed[jLayer] = cseed[jLayer];
3060 if(!bseed[jLayer].IsOK()) continue;
3062 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3063 quality += lQuality[jLayer];
3065 Float_t chi2 = FitTiltedRieman(bseed, kTRUE);
3067 for (Int_t iter = 0; iter < 4; iter++) {
3068 AliDebug(2, Form("Iter[%d] Q[%f] chi2[%f]", iter, quality, chi2));
3070 // Try better cluster set
3071 Int_t nLayers(0); Float_t qualitynew(0.);
3073 TMath::Sort(Int_t(AliTRDgeometry::kNlayer), lQuality, indexes, kFALSE);
3074 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) {
3075 Int_t bLayer = indexes[jLayer];
3076 bseed[bLayer].Reset("c");
3077 if(!(chamber = stack[bLayer])) continue;
3078 if(!bseed[bLayer].AttachClusters(chamber, kTRUE)) continue;
3079 bseed[bLayer].Fit(kTRUE);
3080 if(!bseed[bLayer].IsOK()) continue;
3082 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3083 qualitynew += lQuality[jLayer];
3085 if(rLayers > nLayers){
3086 AliDebug(1, Form("Lost %d tracklets while improving.", rLayers-nLayers));
3088 } else rLayers=nLayers;
3090 if(qualitynew >= quality){
3091 AliDebug(4, Form("Quality worsen in iter[%d].", iter));
3093 } else quality = qualitynew;
3095 // try improve track parameters
3096 AliTRDseedV1 tseed[AliTRDgeometry::kNlayer];
3097 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) tseed[jLayer]=bseed[jLayer];
3098 Float_t chi2new = FitTiltedRieman(tseed, kTRUE);
3100 AliDebug(4, Form("Chi2 worsen in iter[%d].", iter));
3102 } else chi2 = chi2new;
3104 // store better tracklets
3105 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer]=tseed[jLayer];
3108 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 7 && fkReconstructor->IsDebugStreaming()){
3109 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3110 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3111 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
3112 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3113 cstreamer << "ImproveSeedQuality"
3114 << "EventNumber=" << eventNumber
3115 << "CandidateNumber=" << candidateNumber
3116 << "Iteration=" << iter
3117 << "S0.=" << &bseed[0]
3118 << "S1.=" << &bseed[1]
3119 << "S2.=" << &bseed[2]
3120 << "S3.=" << &bseed[3]
3121 << "S4.=" << &bseed[4]
3122 << "S5.=" << &bseed[5]
3123 << "FitterT.=" << tiltedRieman
3127 // we are sure that at least 2 tracklets are OK !
3131 //_________________________________________________________________________
3132 Double_t AliTRDtrackerV1::CalculateTrackLikelihood(const AliTRDseedV1 *const tracklets, Double_t *chi2){
3134 // Calculates the Track Likelihood value. This parameter serves as main quality criterion for
3135 // the track selection
3136 // The likelihood value containes:
3137 // - The chi2 values from the both fitters and the chi2 values in z-direction from a linear fit
3138 // - The Sum of the Parameter |slope_ref - slope_fit|/Sigma of the tracklets
3139 // For all Parameters an exponential dependency is used
3141 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
3142 // - Array of chi2 values:
3143 // * Non-Constrained Tilted Riemann fit
3144 // * Vertex-Constrained Tilted Riemann fit
3145 // * z-Direction from Linear fit
3146 // Output: - The calculated track likelihood
3151 Double_t chi2phi = 0, nLayers = 0;
3152 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
3153 if(!tracklets[iLayer].IsOK()) continue;
3154 chi2phi += tracklets[iLayer].GetChi2Phi();
3157 chi2phi /= Float_t (nLayers - 2.0);
3159 Double_t likeChi2Z = TMath::Exp(-chi2[2] * 0.14); // Chi2Z
3160 Double_t likeChi2TC = (fkRecoParam->IsVertexConstrained()) ?
3161 TMath::Exp(-chi2[1] * 0.677) : 1; // Constrained Tilted Riemann
3162 Double_t likeChi2TR = TMath::Exp(-chi2[0] * 0.0078); // Non-constrained Tilted Riemann
3163 Double_t likeChi2Phi= TMath::Exp(-chi2phi * 3.23);//3.23
3164 Double_t trackLikelihood = likeChi2Z * likeChi2TR * likeChi2Phi;
3166 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3167 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3168 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3169 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3170 cstreamer << "CalculateTrackLikelihood0"
3171 << "EventNumber=" << eventNumber
3172 << "CandidateNumber=" << candidateNumber
3173 << "LikeChi2Z=" << likeChi2Z
3174 << "LikeChi2TR=" << likeChi2TR
3175 << "LikeChi2TC=" << likeChi2TC
3176 << "LikeChi2Phi=" << likeChi2Phi
3177 << "TrackLikelihood=" << trackLikelihood
3181 return trackLikelihood;
3184 //____________________________________________________________________
3185 Double_t AliTRDtrackerV1::CookLikelihood(AliTRDseedV1 *cseed, Int_t planes[4])
3188 // Calculate the probability of this track candidate.
3191 // cseeds : array of candidate tracklets
3192 // planes : array of seeding planes (see seeding configuration)
3193 // chi2 : chi2 values (on the Z and Y direction) from the rieman fit of the track.
3198 // Detailed description
3200 // The track quality is estimated based on the following 4 criteria:
3201 // 1. precision of the rieman fit on the Y direction (likea)
3202 // 2. chi2 on the Y direction (likechi2y)
3203 // 3. chi2 on the Z direction (likechi2z)
3204 // 4. number of attached clusters compared to a reference value
3205 // (see AliTRDrecoParam::fkFindable) (likeN)
3207 // The distributions for each type of probabilities are given below as of
3208 // (date). They have to be checked to assure consistency of estimation.
3211 // ratio of the total number of clusters/track which are expected to be found by the tracker.
3212 Double_t chi2y = GetChi2Y(&cseed[0]);
3213 Double_t chi2z = GetChi2Z(&cseed[0]);
3215 Float_t nclusters = 0.;
3216 Double_t sumda = 0.;
3217 for(UChar_t ilayer = 0; ilayer < 4; ilayer++){
3218 Int_t jlayer = planes[ilayer];
3219 nclusters += cseed[jlayer].GetN2();
3220 sumda += TMath::Abs(cseed[jlayer].GetYfit(1) - cseed[jlayer].GetYref(1));
3224 Double_t likea = TMath::Exp(-sumda * fkRecoParam->GetPhiSlope());
3225 Double_t likechi2y = 0.0000000001;
3226 if (fkReconstructor->IsCosmic() || chi2y < fkRecoParam->GetChi2YCut()) likechi2y += TMath::Exp(-TMath::Sqrt(chi2y) * fkRecoParam->GetChi2YSlope());
3227 Double_t likechi2z = TMath::Exp(-chi2z * fkRecoParam->GetChi2ZSlope());
3228 Double_t likeN = TMath::Exp(-(fkRecoParam->GetNMeanClusters() - nclusters) / fkRecoParam->GetNSigmaClusters());
3229 Double_t like = likea * likechi2y * likechi2z * likeN;
3231 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3232 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3233 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3234 Int_t nTracklets = 0; Float_t meanNcls = 0;
3235 for(Int_t iseed=0; iseed < kNPlanes; iseed++){
3236 if(!cseed[iseed].IsOK()) continue;
3238 meanNcls += cseed[iseed].GetN2();
3240 if(nTracklets) meanNcls /= nTracklets;
3241 // The Debug Stream contains the seed
3242 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3243 cstreamer << "CookLikelihood"
3244 << "EventNumber=" << eventNumber
3245 << "CandidateNumber=" << candidateNumber
3246 << "tracklet0.=" << &cseed[0]
3247 << "tracklet1.=" << &cseed[1]
3248 << "tracklet2.=" << &cseed[2]
3249 << "tracklet3.=" << &cseed[3]
3250 << "tracklet4.=" << &cseed[4]
3251 << "tracklet5.=" << &cseed[5]
3252 << "sumda=" << sumda
3253 << "chi2y=" << chi2y
3254 << "chi2z=" << chi2z
3255 << "likea=" << likea
3256 << "likechi2y=" << likechi2y
3257 << "likechi2z=" << likechi2z
3258 << "nclusters=" << nclusters
3259 << "likeN=" << likeN
3261 << "meanncls=" << meanNcls
3268 //____________________________________________________________________
3269 void AliTRDtrackerV1::GetSeedingConfig(Int_t iconfig, Int_t planes[4])
3272 // Map seeding configurations to detector planes.
3275 // iconfig : configuration index
3276 // planes : member planes of this configuration. On input empty.
3279 // planes : contains the planes which are defining the configuration
3281 // Detailed description
3283 // Here is the list of seeding planes configurations together with
3284 // their topological classification:
3302 // The topologic quality is modeled as follows:
3303 // 1. The general model is define by the equation:
3304 // p(conf) = exp(-conf/2)
3305 // 2. According to the topologic classification, configurations from the same
3306 // class are assigned the agerage value over the model values.
3307 // 3. Quality values are normalized.
3309 // The topologic quality distribution as function of configuration is given below:
3311 // <img src="gif/topologicQA.gif">
3316 case 0: // 5432 TQ 0
3322 case 1: // 4321 TQ 0
3328 case 2: // 3210 TQ 0
3334 case 3: // 5321 TQ 1
3340 case 4: // 4210 TQ 1
3346 case 5: // 5431 TQ 1
3352 case 6: // 4320 TQ 1
3358 case 7: // 5430 TQ 2
3364 case 8: // 5210 TQ 2
3370 case 9: // 5421 TQ 3
3376 case 10: // 4310 TQ 3
3382 case 11: // 5410 TQ 4
3388 case 12: // 5420 TQ 5
3394 case 13: // 5320 TQ 5
3400 case 14: // 5310 TQ 5
3409 //____________________________________________________________________
3410 void AliTRDtrackerV1::GetExtrapolationConfig(Int_t iconfig, Int_t planes[2])
3413 // Returns the extrapolation planes for a seeding configuration.
3416 // iconfig : configuration index
3417 // planes : planes which are not in this configuration. On input empty.
3420 // planes : contains the planes which are not in the configuration
3422 // Detailed description
3426 case 0: // 5432 TQ 0
3430 case 1: // 4321 TQ 0
3434 case 2: // 3210 TQ 0
3438 case 3: // 5321 TQ 1
3442 case 4: // 4210 TQ 1
3446 case 5: // 5431 TQ 1
3450 case 6: // 4320 TQ 1
3454 case 7: // 5430 TQ 2
3458 case 8: // 5210 TQ 2
3462 case 9: // 5421 TQ 3
3466 case 10: // 4310 TQ 3
3470 case 11: // 5410 TQ 4
3474 case 12: // 5420 TQ 5
3478 case 13: // 5320 TQ 5
3482 case 14: // 5310 TQ 5
3489 //____________________________________________________________________
3490 AliCluster* AliTRDtrackerV1::GetCluster(Int_t idx) const
3492 if(!fClusters) return NULL;
3493 Int_t ncls = fClusters->GetEntriesFast();
3494 return idx >= 0 && idx < ncls ? (AliCluster*)fClusters->UncheckedAt(idx) : NULL;
3497 //____________________________________________________________________
3498 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(Int_t idx) const
3500 if(!fTracklets) return NULL;
3501 Int_t ntrklt = fTracklets->GetEntriesFast();
3502 return idx >= 0 && idx < ntrklt ? (AliTRDseedV1*)fTracklets->UncheckedAt(idx) : NULL;
3505 //____________________________________________________________________
3506 AliKalmanTrack* AliTRDtrackerV1::GetTrack(Int_t idx) const
3508 if(!fTracks) return NULL;
3509 Int_t ntrk = fTracks->GetEntriesFast();
3510 return idx >= 0 && idx < ntrk ? (AliKalmanTrack*)fTracks->UncheckedAt(idx) : NULL;
3515 // //_____________________________________________________________________________
3516 // Int_t AliTRDtrackerV1::Freq(Int_t n, const Int_t *inlist
3517 // , Int_t *outlist, Bool_t down)
3520 // // Sort eleements according occurancy
3521 // // The size of output array has is 2*n
3528 // Int_t *sindexS = new Int_t[n]; // Temporary array for sorting
3529 // Int_t *sindexF = new Int_t[2*n];
3530 // for (Int_t i = 0; i < n; i++) {
3534 // TMath::Sort(n,inlist,sindexS,down);
3536 // Int_t last = inlist[sindexS[0]];
3537 // Int_t val = last;
3539 // sindexF[0+n] = last;
3540 // Int_t countPos = 0;
3542 // // Find frequency
3543 // for (Int_t i = 1; i < n; i++) {
3544 // val = inlist[sindexS[i]];
3545 // if (last == val) {
3546 // sindexF[countPos]++;
3550 // sindexF[countPos+n] = val;
3551 // sindexF[countPos]++;
3555 // if (last == val) {
3559 // // Sort according frequency
3560 // TMath::Sort(countPos,sindexF,sindexS,kTRUE);
3562 // for (Int_t i = 0; i < countPos; i++) {
3563 // outlist[2*i ] = sindexF[sindexS[i]+n];
3564 // outlist[2*i+1] = sindexF[sindexS[i]];
3567 // delete [] sindexS;
3568 // delete [] sindexF;
3575 //____________________________________________________________________
3576 void AliTRDtrackerV1::ResetSeedTB()
3578 // reset buffer for seeding time bin layers. If the time bin
3579 // layers are not allocated this function allocates them
3581 for(Int_t isl=0; isl<kNSeedPlanes; isl++){
3582 if(!fSeedTB[isl]) fSeedTB[isl] = new AliTRDchamberTimeBin();
3583 else fSeedTB[isl]->Clear();
3588 //_____________________________________________________________________________
3589 Float_t AliTRDtrackerV1::GetChi2Y(const AliTRDseedV1 * const tracklets) const
3591 // Calculates normalized chi2 in y-direction
3592 // chi2 = Sum chi2 / n_tracklets
3594 Double_t chi2 = 0.; Int_t n = 0;
3595 for(Int_t ipl = kNPlanes; ipl--;){
3596 if(!tracklets[ipl].IsOK()) continue;
3597 chi2 += tracklets[ipl].GetChi2Y();
3600 return n ? chi2/n : 0.;
3603 //_____________________________________________________________________________
3604 Float_t AliTRDtrackerV1::GetChi2Z(const AliTRDseedV1 *const tracklets) const
3606 // Calculates normalized chi2 in z-direction
3607 // chi2 = Sum chi2 / n_tracklets
3609 Double_t chi2 = 0; Int_t n = 0;
3610 for(Int_t ipl = kNPlanes; ipl--;){
3611 if(!tracklets[ipl].IsOK()) continue;
3612 chi2 += tracklets[ipl].GetChi2Z();
3615 return n ? chi2/n : 0.;
3618 //____________________________________________________________________
3619 Float_t AliTRDtrackerV1::CalculateReferenceX(const AliTRDseedV1 *const tracklets){
3621 // Calculates the reference x-position for the tilted Rieman fit defined as middle
3622 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
3623 // are taken into account
3625 // Parameters: - Array of tracklets(AliTRDseedV1)
3627 // Output: - The reference x-position(Float_t)
3628 // Only kept for compatibility with the old code
3630 Int_t nDistances = 0;
3631 Float_t meanDistance = 0.;
3632 Int_t startIndex = 5;
3633 for(Int_t il =5; il > 0; il--){
3634 if(tracklets[il].IsOK() && tracklets[il -1].IsOK()){
3635 Float_t xdiff = tracklets[il].GetX0() - tracklets[il -1].GetX0();
3636 meanDistance += xdiff;
3639 if(tracklets[il].IsOK()) startIndex = il;
3641 if(tracklets[0].IsOK()) startIndex = 0;
3643 // We should normally never get here
3644 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
3645 Int_t iok = 0, idiff = 0;
3646 // This attempt is worse and should be avoided:
3647 // check for two chambers which are OK and repeat this without taking the mean value
3648 // Strategy avoids a division by 0;
3649 for(Int_t il = 5; il >= 0; il--){
3650 if(tracklets[il].IsOK()){
3651 xpos[iok] = tracklets[il].GetX0();
3655 if(iok) idiff++; // to get the right difference;
3659 meanDistance = (xpos[0] - xpos[1])/idiff;
3662 // we have do not even have 2 layers which are OK? The we do not need to fit at all
3667 meanDistance /= nDistances;
3669 return tracklets[startIndex].GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
3672 //_____________________________________________________________________________
3673 Double_t AliTRDtrackerV1::FitTiltedRiemanV1(AliTRDseedV1 *const tracklets){
3675 // Track Fitter Function using the new class implementation of
3678 AliTRDtrackFitterRieman fitter;
3679 fitter.SetRiemanFitter(GetTiltedRiemanFitter());
3681 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) fitter.SetTracklet(il, &tracklets[il]);
3682 Double_t chi2 = fitter.Eval();
3683 // Update the tracklets
3684 Double_t cov[15]; Double_t x0;
3685 memset(cov, 0, sizeof(Double_t) * 15);
3686 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++){
3687 x0 = tracklets[il].GetX0();
3688 tracklets[il].SetYref(0, fitter.GetYat(x0));
3689 tracklets[il].SetZref(0, fitter.GetZat(x0));
3690 tracklets[il].SetYref(1, fitter.GetDyDxAt(x0));
3691 tracklets[il].SetZref(1, fitter.GetDzDx());
3692 tracklets[il].SetC(fitter.GetCurvature());
3693 fitter.GetCovAt(x0, cov);
3694 tracklets[il].SetCovRef(cov);
3695 tracklets[il].SetChi2(chi2);
3700 ///////////////////////////////////////////////////////
3702 // Resources of class AliTRDLeastSquare //
3704 ///////////////////////////////////////////////////////
3706 //_____________________________________________________________________________
3707 AliTRDtrackerV1::AliTRDLeastSquare::AliTRDLeastSquare(){
3709 // Constructor of the nested class AliTRDtrackFitterLeastSquare
3711 // Fast solving linear regresion in 2D
3713 // The data members have the following meaning
3724 // fCovarianceMatrix[0] : s2a
3725 // fCovarianceMatrix[1] : s2b
3726 // fCovarianceMatrix[2] : cov(ab)
3728 memset(fParams, 0, sizeof(Double_t) * 2);
3729 memset(fSums, 0, sizeof(Double_t) * 6);
3730 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3734 //_____________________________________________________________________________
3735 void AliTRDtrackerV1::AliTRDLeastSquare::AddPoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3737 // Adding Point to the fitter
3740 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3742 const Double_t &xpt = *x;
3743 // printf("Adding point x = %f, y = %f, sigma = %f\n", xpt, y, sigmaY);
3745 fSums[1] += weight * xpt;
3746 fSums[2] += weight * y;
3747 fSums[3] += weight * xpt * y;
3748 fSums[4] += weight * xpt * xpt;
3749 fSums[5] += weight * y * y;
3752 //_____________________________________________________________________________
3753 void AliTRDtrackerV1::AliTRDLeastSquare::RemovePoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3755 // Remove Point from the sample
3758 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3760 const Double_t &xpt = *x;
3762 fSums[1] -= weight * xpt;
3763 fSums[2] -= weight * y;
3764 fSums[3] -= weight * xpt * y;
3765 fSums[4] -= weight * xpt * xpt;
3766 fSums[5] -= weight * y * y;
3769 //_____________________________________________________________________________
3770 Bool_t AliTRDtrackerV1::AliTRDLeastSquare::Eval(){
3772 // Evaluation of the fit:
3773 // Calculation of the parameters
3774 // Calculation of the covariance matrix
3777 Double_t det = fSums[0] * fSums[4] - fSums[1] *fSums[1];
3778 if(det==0) return kFALSE;
3780 // for(Int_t isum = 0; isum < 5; isum++)
3781 // printf("fSums[%d] = %f\n", isum, fSums[isum]);
3782 // printf("denominator = %f\n", denominator);
3783 fParams[0] = (fSums[2] * fSums[4] - fSums[1] * fSums[3])/det;
3784 fParams[1] = (fSums[0] * fSums[3] - fSums[1] * fSums[2])/det;
3785 // printf("fParams[0] = %f, fParams[1] = %f\n", fParams[0], fParams[1]);
3787 // Covariance matrix
3788 Double_t den = fSums[0]*fSums[4] - fSums[1]*fSums[1];
3789 fCovarianceMatrix[0] = fSums[4] / den;
3790 fCovarianceMatrix[1] = fSums[0] / den;
3791 fCovarianceMatrix[2] = -fSums[1] / den;
3792 /* fCovarianceMatrix[0] = fSums[4] / fSums[0] - fSums[1] * fSums[1] / (fSums[0] * fSums[0]);
3793 fCovarianceMatrix[1] = fSums[5] / fSums[0] - fSums[2] * fSums[2] / (fSums[0] * fSums[0]);
3794 fCovarianceMatrix[2] = fSums[3] / fSums[0] - fSums[1] * fSums[2] / (fSums[0] * fSums[0]);*/
3801 //_____________________________________________________________________________
3802 Double_t AliTRDtrackerV1::AliTRDLeastSquare::GetFunctionValue(const Double_t *const xpos) const {
3804 // Returns the Function value of the fitted function at a given x-position
3806 return fParams[0] + fParams[1] * (*xpos);
3809 //_____________________________________________________________________________
3810 void AliTRDtrackerV1::AliTRDLeastSquare::GetCovarianceMatrix(Double_t *storage) const {
3812 // Copies the values of the covariance matrix into the storage
3814 memcpy(storage, fCovarianceMatrix, sizeof(Double_t) * 3);
3817 //_____________________________________________________________________________
3818 void AliTRDtrackerV1::AliTRDLeastSquare::Reset(){
3822 memset(fParams, 0, sizeof(Double_t) * 2);
3823 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3824 memset(fSums, 0, sizeof(Double_t) * 6);
3827 ///////////////////////////////////////////////////////
3829 // Resources of class AliTRDtrackFitterRieman //
3831 ///////////////////////////////////////////////////////
3833 //_____________________________________________________________________________
3834 AliTRDtrackerV1::AliTRDtrackFitterRieman::AliTRDtrackFitterRieman():
3840 fSysClusterError(0.)
3843 // Default constructor
3845 fZfitter = new AliTRDLeastSquare;
3846 fCovarPolY = new TMatrixD(3,3);
3847 fCovarPolZ = new TMatrixD(2,2);
3848 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * 6);
3849 memset(fParameters, 0, sizeof(Double_t) * 5);
3850 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3851 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3854 //_____________________________________________________________________________
3855 AliTRDtrackerV1::AliTRDtrackFitterRieman::~AliTRDtrackFitterRieman(){
3859 if(fZfitter) delete fZfitter;
3860 if(fCovarPolY) delete fCovarPolY;
3861 if(fCovarPolZ) delete fCovarPolZ;
3864 //_____________________________________________________________________________
3865 void AliTRDtrackerV1::AliTRDtrackFitterRieman::Reset(){
3870 fTrackFitter->StoreData(kTRUE);
3871 fTrackFitter->ClearPoints();
3877 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * AliTRDgeometry::kNlayer);
3878 memset(fParameters, 0, sizeof(Double_t) * 5);
3879 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3880 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3881 for(Int_t irow = 0; irow < fCovarPolY->GetNrows(); irow++)
3882 for(Int_t icol = 0; icol < fCovarPolY->GetNcols(); icol++){
3883 (*fCovarPolY)(irow, icol) = 0.;
3884 if(irow < 2 && icol < 2)
3885 (*fCovarPolZ)(irow, icol) = 0.;
3889 //_____________________________________________________________________________
3890 void AliTRDtrackerV1::AliTRDtrackFitterRieman::SetTracklet(Int_t itr, AliTRDseedV1 *tracklet){
3892 // Add tracklet into the fitter
3894 if(itr >= AliTRDgeometry::kNlayer) return;
3895 fTracklets[itr] = tracklet;
3898 //_____________________________________________________________________________
3899 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::Eval(){
3902 // 1. Apply linear transformation and store points in the fitter
3903 // 2. Evaluate the fit
3904 // 3. Check if the result of the fit in z-direction is reasonable
3906 // 3a. Fix the parameters 3 and 4 with the results of a simple least
3908 // 3b. Redo the fit with the fixed parameters
3909 // 4. Store fit results (parameters and errors)
3914 fXref = CalculateReferenceX();
3915 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) UpdateFitters(fTracklets[il]);
3916 if(!fTrackFitter->GetNpoints()) return 1e10;
3918 fTrackFitter->Eval();
3920 fParameters[3] = fTrackFitter->GetParameter(3);
3921 fParameters[4] = fTrackFitter->GetParameter(4);
3922 if(!CheckAcceptable(fParameters[3], fParameters[4])) {
3923 fTrackFitter->FixParameter(3, fZfitter->GetFunctionValue(&fXref));
3924 fTrackFitter->FixParameter(4, fZfitter->GetFunctionParameter(1));
3925 fTrackFitter->Eval();
3926 fTrackFitter->ReleaseParameter(3);
3927 fTrackFitter->ReleaseParameter(4);
3928 fParameters[3] = fTrackFitter->GetParameter(3);
3929 fParameters[4] = fTrackFitter->GetParameter(4);
3931 // Update the Fit Parameters and the errors
3932 fParameters[0] = fTrackFitter->GetParameter(0);
3933 fParameters[1] = fTrackFitter->GetParameter(1);
3934 fParameters[2] = fTrackFitter->GetParameter(2);
3936 // Prepare Covariance estimation
3937 (*fCovarPolY)(0,0) = fSumPolY[0]; (*fCovarPolY)(1,1) = fSumPolY[2]; (*fCovarPolY)(2,2) = fSumPolY[4];
3938 (*fCovarPolY)(1,0) = (*fCovarPolY)(0,1) = fSumPolY[1];
3939 (*fCovarPolY)(2,0) = (*fCovarPolY)(0,2) = fSumPolY[2];
3940 (*fCovarPolY)(2,1) = (*fCovarPolY)(1,2) = fSumPolY[3];
3941 fCovarPolY->Invert();
3942 (*fCovarPolZ)(0,0) = fSumPolZ[0]; (*fCovarPolZ)(1,1) = fSumPolZ[2];
3943 (*fCovarPolZ)(1,0) = (*fCovarPolZ)(0,1) = fSumPolZ[1];
3944 fCovarPolZ->Invert();
3945 return fTrackFitter->GetChisquare() / fTrackFitter->GetNpoints();
3948 //_____________________________________________________________________________
3949 void AliTRDtrackerV1::AliTRDtrackFitterRieman::UpdateFitters(AliTRDseedV1 * const tracklet){
3951 // Does the transformations and updates the fitters
3952 // The following transformation is applied
3954 AliTRDcluster *cl = NULL;
3955 Double_t x, y, z, dx, t, w, we, yerr, zerr;
3957 if(!tracklet || !tracklet->IsOK()) return;
3958 Double_t tilt = tracklet->GetTilt();
3959 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
3960 if(!(cl = tracklet->GetClusters(itb))) continue;
3961 if(!cl->IsInChamber()) continue;
3962 if (!tracklet->IsUsable(itb)) continue;
3969 uvt[0] = 2. * x * t;
3971 uvt[2] = 2. * tilt * t;
3972 uvt[3] = 2. * tilt * dx * t;
3973 w = 2. * (y + tilt*z) * t;
3974 // error definition changes for the different calls
3976 we *= TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2());
3977 // Update sums for error calculation
3978 yerr = 1./(TMath::Sqrt(cl->GetSigmaY2()) + fSysClusterError);
3980 zerr = 1./cl->GetSigmaZ2();
3981 for(Int_t ipol = 0; ipol < 5; ipol++){
3982 fSumPolY[ipol] += yerr;
3985 fSumPolZ[ipol] += zerr;
3989 fTrackFitter->AddPoint(uvt, w, we);
3990 fZfitter->AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
3994 //_____________________________________________________________________________
3995 Bool_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CheckAcceptable(Double_t offset, Double_t slope){
3997 // Check whether z-results are acceptable
3998 // Definition: Distance between tracklet fit and track fit has to be
3999 // less then half a padlength
4000 // Point of comparision is at the anode wire
4002 Bool_t acceptablez = kTRUE;
4003 Double_t zref = 0.0;
4004 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
4005 if(!fTracklets[iLayer]->IsOK()) continue;
4006 zref = offset + slope * (fTracklets[iLayer]->GetX0() - fXref);
4007 if (TMath::Abs(fTracklets[iLayer]->GetZfit(0) - zref) > fTracklets[iLayer]->GetPadLength() * 0.5 + 1.0)
4008 acceptablez = kFALSE;
4013 //_____________________________________________________________________________
4014 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetYat(Double_t x) const {
4016 // Calculate y position out of the track parameters
4017 // y: R^2 = (x - x0)^2 + (y - y0)^2
4018 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
4019 // R = Sqrt() = 1/Curvature
4020 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
4023 Double_t disc = (x * fParameters[0] + fParameters[1]);
4024 disc = 1 - fParameters[0]*fParameters[2] + fParameters[1]*fParameters[1] - disc*disc;
4026 disc = TMath::Sqrt(disc);
4027 y = (1.0 - disc) / fParameters[0];
4032 //_____________________________________________________________________________
4033 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetZat(Double_t x) const {
4035 // Return z position for a given x position
4036 // Simple linear function
4038 return fParameters[3] + fParameters[4] * (x - fXref);
4041 //_____________________________________________________________________________
4042 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetDyDxAt(Double_t x) const {
4044 // Calculate dydx at a given radial position out of the track parameters
4045 // dy: R^2 = (x - x0)^2 + (y - y0)^2
4046 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
4047 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
4048 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
4049 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
4051 Double_t x0 = -fParameters[1] / fParameters[0];
4052 Double_t curvature = GetCurvature();
4054 if (-fParameters[2] * fParameters[0] + fParameters[1] * fParameters[1] + 1 > 0) {
4055 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
4056 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
4057 if (fParameters[0] < 0) yderiv *= -1.0;
4064 //_____________________________________________________________________________
4065 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCurvature() const {
4067 // Calculate track curvature
4070 Double_t curvature = 1.0 + fParameters[1]*fParameters[1] - fParameters[2]*fParameters[0];
4071 if (curvature > 0.0)
4072 curvature = fParameters[0] / TMath::Sqrt(curvature);
4076 //_____________________________________________________________________________
4077 void AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCovAt(Double_t x, Double_t *cov) const {
4079 // Error Definition according to gauss error propagation
4081 TMatrixD transform(3,3);
4082 transform(0,0) = transform(1,1) = transform(2,2) = 1;
4083 transform(0,1) = transform(1,2) = x;
4084 transform(0,2) = x*x;
4085 TMatrixD covariance(transform, TMatrixD::kMult, *fCovarPolY);
4086 covariance *= transform.T();
4087 cov[0] = covariance(0,0);
4088 TMatrixD transformZ(2,2);
4089 transformZ(0,0) = transformZ(1,1) = 1;
4090 transformZ(0,1) = x;
4091 TMatrixD covarZ(transformZ, TMatrixD::kMult, *fCovarPolZ);
4092 covarZ *= transformZ.T();
4093 cov[1] = covarZ(0,0);
4097 //____________________________________________________________________
4098 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CalculateReferenceX(){
4100 // Calculates the reference x-position for the tilted Rieman fit defined as middle
4101 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
4102 // are taken into account
4104 // Parameters: - Array of tracklets(AliTRDseedV1)
4106 // Output: - The reference x-position(Float_t)
4108 Int_t nDistances = 0;
4109 Float_t meanDistance = 0.;
4110 Int_t startIndex = 5;
4111 for(Int_t il =5; il > 0; il--){
4112 if(fTracklets[il]->IsOK() && fTracklets[il -1]->IsOK()){
4113 Float_t xdiff = fTracklets[il]->GetX0() - fTracklets[il -1]->GetX0();
4114 meanDistance += xdiff;
4117 if(fTracklets[il]->IsOK()) startIndex = il;
4119 if(fTracklets[0]->IsOK()) startIndex = 0;
4121 // We should normally never get here
4122 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
4123 Int_t iok = 0, idiff = 0;
4124 // This attempt is worse and should be avoided:
4125 // check for two chambers which are OK and repeat this without taking the mean value
4126 // Strategy avoids a division by 0;
4127 for(Int_t il = 5; il >= 0; il--){
4128 if(fTracklets[il]->IsOK()){
4129 xpos[iok] = fTracklets[il]->GetX0();
4133 if(iok) idiff++; // to get the right difference;
4137 meanDistance = (xpos[0] - xpos[1])/idiff;
4140 // we have do not even have 2 layers which are OK? The we do not need to fit at all
4145 meanDistance /= nDistances;
4147 return fTracklets[startIndex]->GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());