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");
280 printf("TB[%d] new TB[%d]\n", fgNTimeBins, fkReconstructor->GetNTimeBins());
281 if (!fgNTimeBins) fgNTimeBins = fkReconstructor->GetNTimeBins();
284 Int_t nFound = 0, // number of tracks found
285 nSeeds = 0, // total number of ESD seeds
286 nTRDseeds= 0, // number of seeds in the TRD acceptance
287 nTPCseeds= 0; // number of TPC seeds
288 Float_t foundMin = 20.0;
290 Float_t *quality = NULL;
292 nSeeds = event->GetNumberOfTracks();
293 // Sort tracks according to quality
294 // (covariance in the yz plane)
296 quality = new Float_t[nSeeds];
297 index = new Int_t[nSeeds];
298 for (Int_t iSeed = nSeeds; iSeed--;) {
299 AliESDtrack *seed = event->GetTrack(iSeed);
300 Double_t covariance[15];
301 seed->GetExternalCovariance(covariance);
302 quality[iSeed] = covariance[0] + covariance[2];
304 TMath::Sort(nSeeds, quality, index,kFALSE);
307 // Propagate all seeds
310 for (Int_t iSeed = 0; iSeed < nSeeds; iSeed++) {
312 // Get the seeds in sorted sequence
313 AliESDtrack *seed = event->GetTrack(index[iSeed]);
314 Float_t p4 = seed->GetC(seed->GetBz());
316 // Check the seed status
317 ULong_t status = seed->GetStatus();
318 if ((status & AliESDtrack::kTPCout) == 0) continue;
319 if ((status & AliESDtrack::kTRDout) != 0) continue;
321 // Propagate to the entrance in the TRD mother volume
322 new(&track) AliTRDtrackV1(*seed);
323 if(AliTRDgeometry::GetXtrdBeg() > (fgkMaxStep + track.GetX()) && !PropagateToX(track, AliTRDgeometry::GetXtrdBeg(), fgkMaxStep)){
324 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
327 if(!AdjustSector(&track)){
328 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
331 if(TMath::Abs(track.GetSnp()) > fgkMaxSnp) {
332 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
338 // store track status at TRD entrance
339 seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
341 // prepare track and do propagation in the TRD
342 track.SetReconstructor(fkReconstructor);
343 track.SetKink(Bool_t(seed->GetKinkIndex(0)));
344 expectedClr = FollowBackProlongation(track);
345 // check if track entered the TRD fiducial volume
346 if(track.GetTrackLow()){
347 seed->UpdateTrackParams(&track, AliESDtrack::kTRDin);
350 // check if track was stopped in the TRD
352 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
358 // computes PID for track
360 // update calibration references using this track
361 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(&track);
362 // save calibration object
363 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0 &&
364 fkRecoParam->IsOverPtThreshold(track.Pt())){
365 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(track);
366 calibTrack->SetOwner();
367 seed->AddCalibObject(calibTrack);
370 seed->UpdateTrackParams(&track, AliESDtrack::kTRDout);
371 track.UpdateESDtrack(seed);
374 if ((TMath::Abs(track.GetC(track.GetBz()) - p4) / TMath::Abs(p4) < 0.2) ||(track.Pt() > 0.8)) {
376 // Make backup for back propagation
377 Int_t foundClr = track.GetNumberOfClusters();
378 if (foundClr >= foundMin) {
379 track.CookLabel(1. - fgkLabelFraction);
380 //if(track.GetBackupTrack()) UseClusters(track.GetBackupTrack());
382 // Sign only gold tracks
383 if (track.GetChi2() / track.GetNumberOfClusters() < 4) {
384 //if ((seed->GetKinkIndex(0) == 0) && (track.Pt() < 1.5)) UseClusters(&track);
386 Bool_t isGold = kFALSE;
389 if (track.GetChi2() / track.GetNumberOfClusters() < 5) {
390 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
396 if ((!isGold) && (track.GetNCross() == 0) && (track.GetChi2() / track.GetNumberOfClusters() < 7)) {
397 //seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
398 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
403 if ((!isGold) && (track.GetBackupTrack())) {
404 if ((track.GetBackupTrack()->GetNumberOfClusters() > foundMin) && ((track.GetBackupTrack()->GetChi2()/(track.GetBackupTrack()->GetNumberOfClusters()+1)) < 7)) {
405 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]", nFound));
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
975 // TO DO update quality check of the track.
976 // consider comparison with fTimeBinsRange
977 Float_t ratio0 = ptrTracklet->GetN() / Float_t(fgNTimeBins);
978 //Float_t ratio1 = Float_t(t.GetNumberOfClusters()+1) / Float_t(t.GetNExpected()+1);
983 //(ratio0+ratio1 > 1.5) &&
984 (t.GetNCross() == 0) &&
985 (TMath::Abs(t.GetSnp()) < 0.85) &&
986 (t.GetNumberOfClusters() > 20)){
988 } else AliDebug(2, Form("Failed backup : \n"
989 "chi2 < 18.0 [%c] chi2=%f\n"
990 "ratio0 > 0.8 [%c] ratio=%f\n"
991 "t.GetNCross()==0 [%c] crosses=%d\n"
992 "Abs(t.GetSnp())<0.85 [%c] snp=%f\n"
993 "t.GetNumberOfClusters()>20 [%c] ncls=%d"
994 ,(chi2<18.0)?'y':'n', chi2
995 ,(ratio0>0.8)?'y':'n', ratio0
996 ,(t.GetNCross()==0)?'y':'n', t.GetNCross()
997 ,(TMath::Abs(t.GetSnp())<0.85)?'y':'n', TMath::Abs(t.GetSnp())
998 ,(t.GetNumberOfClusters()>20)?'y':'n', t.GetNumberOfClusters()
1001 } // end layers loop
1002 //printf("clusters[%d] chi2[%f] x[%f] status[%d ", n, t.GetChi2(), t.GetX(), t.GetStatusTRD());
1003 //for(int i=0; i<6; i++) printf("%d ", t.GetStatusTRD(i)); printf("]\n");
1006 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1007 AliTRDtrackV1 track(t);
1009 (*cstreamer) << "FollowBackProlongation0"
1010 << "EventNumber=" << eventNumber
1012 << "track.=" << &track
1019 //_________________________________________________________________________
1020 Float_t AliTRDtrackerV1::FitRieman(AliTRDseedV1 *tracklets, Double_t *chi2, Int_t *const planes){
1022 // Fits a Riemann-circle to the given points without tilting pad correction.
1023 // The fit is performed using an instance of the class AliRieman (equations
1024 // and transformations see documentation of this class)
1025 // Afterwards all the tracklets are Updated
1027 // Parameters: - Array of tracklets (AliTRDseedV1)
1028 // - Storage for the chi2 values (beginning with direction z)
1029 // - Seeding configuration
1030 // Output: - The curvature
1032 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1034 Int_t allplanes[] = {0, 1, 2, 3, 4, 5};
1035 Int_t *ppl = &allplanes[0];
1036 Int_t maxLayers = 6;
1041 for(Int_t il = 0; il < maxLayers; il++){
1042 if(!tracklets[ppl[il]].IsOK()) continue;
1043 fitter->AddPoint(tracklets[ppl[il]].GetX0(), tracklets[ppl[il]].GetYfit(0), tracklets[ppl[il]].GetZfit(0),1,10);
1046 // Set the reference position of the fit and calculate the chi2 values
1047 memset(chi2, 0, sizeof(Double_t) * 2);
1048 for(Int_t il = 0; il < maxLayers; il++){
1049 // Reference positions
1050 tracklets[ppl[il]].Init(fitter);
1053 if((!tracklets[ppl[il]].IsOK()) && (!planes)) continue;
1054 chi2[0] += tracklets[ppl[il]].GetChi2Y();
1055 chi2[1] += tracklets[ppl[il]].GetChi2Z();
1057 return fitter->GetC();
1060 //_________________________________________________________________________
1061 void AliTRDtrackerV1::FitRieman(AliTRDcluster **seedcl, Double_t chi2[2])
1064 // Performs a Riemann helix fit using the seedclusters as spacepoints
1065 // Afterwards the chi2 values are calculated and the seeds are updated
1067 // Parameters: - The four seedclusters
1068 // - The tracklet array (AliTRDseedV1)
1069 // - The seeding configuration
1074 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1076 for(Int_t i = 0; i < 4; i++){
1077 fitter->AddPoint(seedcl[i]->GetX(), seedcl[i]->GetY(), seedcl[i]->GetZ(), 1., 10.);
1082 // Update the seed and calculated the chi2 value
1083 chi2[0] = 0; chi2[1] = 0;
1084 for(Int_t ipl = 0; ipl < kNSeedPlanes; ipl++){
1086 chi2[0] += (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX()));
1087 chi2[1] += (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX()));
1092 //_________________________________________________________________________
1093 Float_t AliTRDtrackerV1::FitTiltedRiemanConstraint(AliTRDseedV1 *tracklets, Double_t zVertex)
1096 // Fits a helix to the clusters. Pad tilting is considered. As constraint it is
1097 // assumed that the vertex position is set to 0.
1098 // This method is very usefull for high-pt particles
1099 // Basis for the fit: (x - x0)^2 + (y - y0)^2 - R^2 = 0
1100 // x0, y0: Center of the circle
1101 // Measured y-position: ymeas = y - tan(phiT)(zc - zt)
1102 // zc: center of the pad row
1103 // Equation which has to be fitted (after transformation):
1104 // a + b * u + e * v + 2*(ymeas + tan(phiT)(z - zVertex))*t = 0
1106 // t = 1/(x^2 + y^2)
1108 // v = 2 * x * tan(phiT) * t
1109 // Parameters in the equation:
1110 // a = -1/y0, b = x0/y0, e = dz/dx
1112 // The Curvature is calculated by the following equation:
1113 // - curv = a/Sqrt(b^2 + 1) = 1/R
1114 // Parameters: - the 6 tracklets
1115 // - the Vertex constraint
1116 // Output: - the Chi2 value of the track
1121 TLinearFitter *fitter = GetTiltedRiemanFitterConstraint();
1122 fitter->StoreData(kTRUE);
1123 fitter->ClearPoints();
1124 AliTRDcluster *cl = NULL;
1126 Float_t x, y, z, w, t, error, tilt;
1129 for(Int_t ilr = 0; ilr < AliTRDgeometry::kNlayer; ilr++){
1130 if(!tracklets[ilr].IsOK()) continue;
1131 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1132 if(!tracklets[ilr].IsUsable(itb)) continue;
1133 cl = tracklets[ilr].GetClusters(itb);
1134 if(!cl->IsInChamber()) continue;
1138 tilt = tracklets[ilr].GetTilt();
1140 t = 1./(x * x + y * y);
1141 uvt[0] = 2. * x * t;
1142 uvt[1] = 2. * x * t * tilt ;
1143 w = 2. * (y + tilt * (z - zVertex)) * t;
1144 error = 2. * TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) * t;
1145 fitter->AddPoint(uvt, w, error);
1151 // Calculate curvature
1152 Double_t a = fitter->GetParameter(0);
1153 Double_t b = fitter->GetParameter(1);
1154 Double_t curvature = a/TMath::Sqrt(b*b + 1);
1156 Float_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1157 for(Int_t ip = 0; ip < AliTRDtrackerV1::kNPlanes; ip++)
1158 tracklets[ip].SetC(curvature);
1160 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker()) >= 5){
1161 //Linear Model on z-direction
1162 Double_t xref = CalculateReferenceX(tracklets); // Relative to the middle of the stack
1163 Double_t slope = fitter->GetParameter(2);
1164 Double_t zref = slope * xref;
1165 Float_t chi2Z = CalculateChi2Z(tracklets, zref, slope, xref);
1166 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1167 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1168 TTreeSRedirector &treeStreamer = *fkReconstructor->GetDebugStream(AliTRDReconstructor::kTracker);
1169 treeStreamer << "FitTiltedRiemanConstraint"
1170 << "EventNumber=" << eventNumber
1171 << "CandidateNumber=" << candidateNumber
1172 << "Curvature=" << curvature
1173 << "Chi2Track=" << chi2track
1174 << "Chi2Z=" << chi2Z
1181 //_________________________________________________________________________
1182 Float_t AliTRDtrackerV1::FitTiltedRieman(AliTRDseedV1 *tracklets, Bool_t sigError)
1185 // Performs a Riemann fit taking tilting pad correction into account
1186 // The equation of a Riemann circle, where the y position is substituted by the
1187 // measured y-position taking pad tilting into account, has to be transformed
1188 // into a 4-dimensional hyperplane equation
1189 // Riemann circle: (x-x0)^2 + (y-y0)^2 -R^2 = 0
1190 // Measured y-Position: ymeas = y - tan(phiT)(zc - zt)
1191 // zc: center of the pad row
1192 // zt: z-position of the track
1193 // The z-position of the track is assumed to be linear dependent on the x-position
1194 // Transformed equation: a + b * u + c * t + d * v + e * w - 2 * (ymeas + tan(phiT) * zc) * t = 0
1195 // Transformation: u = 2 * x * t
1196 // v = 2 * tan(phiT) * t
1197 // w = 2 * tan(phiT) * (x - xref) * t
1198 // t = 1 / (x^2 + ymeas^2)
1199 // Parameters: a = -1/y0
1201 // c = (R^2 -x0^2 - y0^2)/y0
1204 // If the offset respectively the slope in z-position is impossible, the parameters are fixed using
1205 // results from the simple riemann fit. Afterwards the fit is redone.
1206 // The curvature is calculated according to the formula:
1207 // curv = a/(1 + b^2 + c*a) = 1/R
1209 // Paramters: - Array of tracklets (connected to the track candidate)
1210 // - Flag selecting the error definition
1211 // Output: - Chi2 values of the track (in Parameter list)
1213 TLinearFitter *fitter = GetTiltedRiemanFitter();
1214 fitter->StoreData(kTRUE);
1215 fitter->ClearPoints();
1216 AliTRDLeastSquare zfitter;
1217 AliTRDcluster *cl = NULL;
1219 Double_t xref = CalculateReferenceX(tracklets);
1220 Double_t x, y, z, t, tilt, dx, w, we, erry, errz;
1221 Double_t uvt[4], sumPolY[5], sumPolZ[3];
1222 memset(sumPolY, 0, sizeof(Double_t) * 5);
1223 memset(sumPolZ, 0, sizeof(Double_t) * 3);
1225 // Containers for Least-square fitter
1226 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1227 if(!tracklets[ipl].IsOK()) continue;
1228 tilt = tracklets[ipl].GetTilt();
1229 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1230 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1231 if(!cl->IsInChamber()) continue;
1232 if (!tracklets[ipl].IsUsable(itb)) continue;
1239 uvt[0] = 2. * x * t;
1241 uvt[2] = 2. * tilt * t;
1242 uvt[3] = 2. * tilt * dx * t;
1243 w = 2. * (y + tilt*z) * t;
1244 // error definition changes for the different calls
1246 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) : 0.2;
1247 fitter->AddPoint(uvt, w, we);
1248 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1249 // adding points for covariance matrix estimation
1250 erry = 1./(TMath::Sqrt(cl->GetSigmaY2()) + 0.1); // 0.1 is a systematic error (due to misalignment and miscalibration)
1252 errz = 1./cl->GetSigmaZ2();
1253 for(Int_t ipol = 0; ipol < 5; ipol++){
1254 sumPolY[ipol] += erry;
1257 sumPolZ[ipol] += errz;
1267 Double_t offset = fitter->GetParameter(3);
1268 Double_t slope = fitter->GetParameter(4);
1270 // Linear fitter - not possible to make boundaries
1271 // Do not accept non possible z and dzdx combinations
1272 Bool_t acceptablez = kTRUE;
1273 Double_t zref = 0.0;
1274 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1275 if(!tracklets[iLayer].IsOK()) continue;
1276 zref = offset + slope * (tracklets[iLayer].GetX0() - xref);
1277 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1278 acceptablez = kFALSE;
1281 Double_t dzmf = zfitter.GetFunctionParameter(1);
1282 Double_t zmf = zfitter.GetFunctionValue(&xref);
1283 fgTiltedRieman->FixParameter(3, zmf);
1284 fgTiltedRieman->FixParameter(4, dzmf);
1286 fitter->ReleaseParameter(3);
1287 fitter->ReleaseParameter(4);
1288 offset = fitter->GetParameter(3);
1289 slope = fitter->GetParameter(4);
1292 // Calculate Curvarture
1293 Double_t a = fitter->GetParameter(0);
1294 Double_t b = fitter->GetParameter(1);
1295 Double_t c = fitter->GetParameter(2);
1296 Double_t curvature = 1.0 + b*b - c*a;
1297 if (curvature > 0.0)
1298 curvature = a / TMath::Sqrt(curvature);
1300 Double_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1302 // Prepare error calculation
1303 TMatrixD covarPolY(3,3);
1304 covarPolY(0,0) = sumPolY[0]; covarPolY(1,1) = sumPolY[2]; covarPolY(2,2) = sumPolY[4];
1305 covarPolY(0,1) = covarPolY(1,0) = sumPolY[1];
1306 covarPolY(0,2) = covarPolY(2,0) = sumPolY[2];
1307 covarPolY(2,1) = covarPolY(1,2) = sumPolY[3];
1309 TMatrixD covarPolZ(2,2);
1310 covarPolZ(0,0) = sumPolZ[0]; covarPolZ(1,1) = sumPolZ[2];
1311 covarPolZ(1,0) = covarPolZ(0,1) = sumPolZ[1];
1314 // Update the tracklets
1315 Double_t x1, dy, dz;
1317 memset(cov, 0, sizeof(Double_t) * 15);
1318 for(Int_t iLayer = 0; iLayer < AliTRDtrackerV1::kNPlanes; iLayer++) {
1320 x = tracklets[iLayer].GetX0();
1326 memset(cov, 0, sizeof(Double_t) * 3);
1327 TMatrixD transform(3,3);
1330 transform(0,2) = x*x;
1334 TMatrixD covariance(transform, TMatrixD::kMult, covarPolY);
1335 covariance *= transform.T();
1336 TMatrixD transformZ(2,2);
1337 transformZ(0,0) = transformZ(1,1) = 1;
1338 transformZ(0,1) = x;
1339 TMatrixD covarZ(transformZ, TMatrixD::kMult, covarPolZ);
1340 covarZ *= transformZ.T();
1341 // y: R^2 = (x - x0)^2 + (y - y0)^2
1342 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1343 // R = Sqrt() = 1/Curvature
1344 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
1345 Double_t res = (x * a + b); // = (x - x0)/y0
1347 res = 1.0 - c * a + b * b - res; // = (R^2 - (x - x0)^2)/y0^2
1349 res = TMath::Sqrt(res);
1350 y = (1.0 - res) / a;
1352 cov[0] = covariance(0,0);
1353 cov[2] = covarZ(0,0);
1356 // dy: R^2 = (x - x0)^2 + (y - y0)^2
1357 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
1358 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1359 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
1360 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
1361 Double_t x0 = -b / a;
1362 if (-c * a + b * b + 1 > 0) {
1363 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
1364 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
1365 if (a < 0) yderiv *= -1.0;
1369 z = offset + slope * (x - xref);
1371 tracklets[iLayer].SetYref(0, y);
1372 tracklets[iLayer].SetYref(1, dy);
1373 tracklets[iLayer].SetZref(0, z);
1374 tracklets[iLayer].SetZref(1, dz);
1375 tracklets[iLayer].SetC(curvature);
1376 tracklets[iLayer].SetCovRef(cov);
1377 tracklets[iLayer].SetChi2(chi2track);
1380 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >=5){
1381 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
1382 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1383 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1384 Double_t chi2z = CalculateChi2Z(tracklets, offset, slope, xref);
1385 cstreamer << "FitTiltedRieman0"
1386 << "EventNumber=" << eventNumber
1387 << "CandidateNumber=" << candidateNumber
1389 << "Chi2Z=" << chi2z
1396 //____________________________________________________________________
1397 Double_t AliTRDtrackerV1::FitLine(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t err, Int_t np, AliTrackPoint *points)
1400 // Fit track with a staight line
1401 // Fills an AliTrackPoint array with np points
1402 // Function should be used to refit tracks when no magnetic field was on
1404 AliTRDLeastSquare yfitter, zfitter;
1405 AliTRDcluster *cl = NULL;
1407 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1409 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1410 if(!(tracklet = track->GetTracklet(ipl))) continue;
1411 if(!tracklet->IsOK()) continue;
1412 new(&work[ipl]) AliTRDseedV1(*tracklet);
1414 tracklets = &work[0];
1417 Double_t xref = CalculateReferenceX(tracklets);
1418 Double_t x, y, z, dx, ye, yr, tilt;
1419 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1420 if(!tracklets[ipl].IsOK()) continue;
1421 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1422 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1423 if (!tracklets[ipl].IsUsable(itb)) continue;
1427 zfitter.AddPoint(&dx, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1431 Double_t z0 = zfitter.GetFunctionParameter(0);
1432 Double_t dzdx = zfitter.GetFunctionParameter(1);
1433 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1434 if(!tracklets[ipl].IsOK()) continue;
1435 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1436 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1437 if (!tracklets[ipl].IsUsable(itb)) continue;
1441 tilt = tracklets[ipl].GetTilt();
1443 yr = y + tilt*(z - z0 - dzdx*dx);
1444 // error definition changes for the different calls
1445 ye = tilt*TMath::Sqrt(cl->GetSigmaZ2());
1446 ye += err ? tracklets[ipl].GetSigmaY() : 0.2;
1447 yfitter.AddPoint(&dx, yr, ye);
1451 Double_t y0 = yfitter.GetFunctionParameter(0);
1452 Double_t dydx = yfitter.GetFunctionParameter(1);
1453 Double_t chi2 = 0.;//yfitter.GetChisquare()/Double_t(nPoints);
1455 //update track points array
1458 for(int ip=0; ip<np; ip++){
1459 points[ip].GetXYZ(xyz);
1460 xyz[1] = y0 + dydx * (xyz[0] - xref);
1461 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1462 points[ip].SetXYZ(xyz);
1469 //_________________________________________________________________________
1470 Double_t AliTRDtrackerV1::FitRiemanTilt(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t sigError, Int_t np, AliTrackPoint *points)
1473 // Performs a Riemann fit taking tilting pad correction into account
1475 // Paramters: - Array of tracklets (connected to the track candidate)
1476 // - Flag selecting the error definition
1477 // Output: - Chi2 values of the track (in Parameter list)
1479 // The equations which has to be solved simultaneously are:
1481 // R^{2} = (x-x_{0})^{2} + (y^{*}-y_{0})^{2}
1482 // y^{*} = y - tg(h)(z - z_{t})
1483 // z_{t} = z_{0}+dzdx*(x-x_{r})
1485 // with (x, y, z) the coordinate of the cluster, (x_0, y_0, z_0) the coordinate of the center of the Riemann circle,
1486 // R its radius, x_r a constant refrence radial position in the middle of the TRD stack and dzdx the slope of the
1487 // track in the x-z plane. Using the following transformations
1489 // t = 1 / (x^{2} + y^{2})
1491 // v = 2 * tan(h) * t
1492 // w = 2 * tan(h) * (x - x_{r}) * t
1494 // One gets the following linear equation
1496 // a + b * u + c * t + d * v + e * w = 2 * (y + tg(h) * z) * t
1498 // where the coefficients have the following meaning
1502 // c = (R^{2} -x_{0}^{2} - y_{0}^{2})/y_{0}
1506 // The error calculation for the free term is thus
1508 // #sigma = 2 * #sqrt{#sigma^{2}_{y} + (tilt corr ...) + tg^{2}(h) * #sigma^{2}_{z}} * t
1511 // From this simple model one can compute chi^2 estimates and a rough approximation of pt from the curvature according
1514 // C = 1/R = a/(1 + b^{2} + c*a)
1518 // M.Ivanov <M.Ivanov@gsi.de>
1519 // A.Bercuci <A.Bercuci@gsi.de>
1520 // M.Fasel <M.Fasel@gsi.de>
1522 TLinearFitter *fitter = GetTiltedRiemanFitter();
1523 fitter->StoreData(kTRUE);
1524 fitter->ClearPoints();
1525 AliTRDLeastSquare zfitter;
1526 AliTRDcluster *cl = NULL;
1528 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1530 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1531 if(!(tracklet = track->GetTracklet(ipl))) continue;
1532 if(!tracklet->IsOK()) continue;
1533 new(&work[ipl]) AliTRDseedV1(*tracklet);
1535 tracklets = &work[0];
1538 Double_t xref = CalculateReferenceX(tracklets);
1539 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1540 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));
1541 Double_t x, y, z, t, tilt, dx, w, we;
1544 // Containers for Least-square fitter
1545 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1546 if(!tracklets[ipl].IsOK()) continue;
1547 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1548 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1549 //if (!tracklets[ipl].IsUsable(itb)) continue;
1553 tilt = tracklets[ipl].GetTilt();
1557 uvt[0] = 2. * x * t;
1559 uvt[2] = 2. * tilt * t;
1560 uvt[3] = 2. * tilt * dx * t;
1561 w = 2. * (y + tilt*z) * t;
1562 // error definition changes for the different calls
1564 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()) : 0.2;
1565 fitter->AddPoint(uvt, w, we);
1566 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1570 if(fitter->Eval()) return 1.E10;
1572 Double_t z0 = fitter->GetParameter(3);
1573 Double_t dzdx = fitter->GetParameter(4);
1576 // Linear fitter - not possible to make boundaries
1577 // Do not accept non possible z and dzdx combinations
1578 Bool_t accept = kTRUE;
1579 Double_t zref = 0.0;
1580 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1581 if(!tracklets[iLayer].IsOK()) continue;
1582 zref = z0 + dzdx * (tracklets[iLayer].GetX0() - xref);
1583 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1588 Double_t dzmf = zfitter.GetFunctionParameter(1);
1589 Double_t zmf = zfitter.GetFunctionValue(&xref);
1590 fitter->FixParameter(3, zmf);
1591 fitter->FixParameter(4, dzmf);
1593 fitter->ReleaseParameter(3);
1594 fitter->ReleaseParameter(4);
1595 z0 = fitter->GetParameter(3); // = zmf ?
1596 dzdx = fitter->GetParameter(4); // = dzmf ?
1599 // Calculate Curvature
1600 Double_t a = fitter->GetParameter(0);
1601 Double_t b = fitter->GetParameter(1);
1602 Double_t c = fitter->GetParameter(2);
1603 Double_t y0 = 1. / a;
1604 Double_t x0 = -b * y0;
1605 Double_t tmp = y0*y0 + x0*x0 - c*y0;
1606 if(tmp<=0.) return 1.E10;
1607 Double_t radius = TMath::Sqrt(tmp);
1608 Double_t curvature = 1.0 + b*b - c*a;
1609 if (curvature > 0.0) curvature = a / TMath::Sqrt(curvature);
1611 // Calculate chi2 of the fit
1612 Double_t chi2 = fitter->GetChisquare()/Double_t(nPoints);
1613 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1614 Form("x0[%6.2f] y0[%6.2f] R[%6.2f] chi2[%f]\n", x0, y0, radius, chi2));
1616 // Update the tracklets
1618 for(Int_t ip = 0; ip < kNPlanes; ip++) {
1619 x = tracklets[ip].GetX0();
1620 tmp = radius*radius-(x-x0)*(x-x0);
1621 if(tmp <= 0.) continue;
1622 tmp = TMath::Sqrt(tmp);
1624 // y: R^2 = (x - x0)^2 + (y - y0)^2
1625 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1626 tracklets[ip].SetYref(0, y0 - (y0>0.?1.:-1)*tmp);
1627 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1628 tracklets[ip].SetYref(1, (x - x0) / tmp);
1629 tracklets[ip].SetZref(0, z0 + dzdx * (x - xref));
1630 tracklets[ip].SetZref(1, dzdx);
1631 tracklets[ip].SetC(curvature);
1632 tracklets[ip].SetChi2(chi2);
1635 //update track points array
1638 for(int ip=0; ip<np; ip++){
1639 points[ip].GetXYZ(xyz);
1640 xyz[1] = TMath::Abs(xyz[0] - x0) > radius ? 100. : y0 - (y0>0.?1.:-1.)*TMath::Sqrt((radius-(xyz[0]-x0))*(radius+(xyz[0]-x0)));
1641 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1642 points[ip].SetXYZ(xyz);
1650 //____________________________________________________________________
1651 Double_t AliTRDtrackerV1::FitKalman(AliTRDtrackV1 *track, AliTRDseedV1 * const tracklets, Bool_t up, Int_t np, AliTrackPoint *points)
1653 // Kalman filter implementation for the TRD.
1654 // It returns the positions of the fit in the array "points"
1656 // Author : A.Bercuci@gsi.de
1658 // printf("Start track @ x[%f]\n", track->GetX());
1660 //prepare marker points along the track
1661 Int_t ip = np ? 0 : 1;
1663 if((up?-1:1) * (track->GetX() - points[ip].GetX()) > 0.) break;
1664 //printf("AliTRDtrackerV1::FitKalman() : Skip track marker x[%d] = %7.3f. Before track start ( %7.3f ).\n", ip, points[ip].GetX(), track->GetX());
1667 //if(points) printf("First marker point @ x[%d] = %f\n", ip, points[ip].GetX());
1670 AliTRDseedV1 tracklet, *ptrTracklet = NULL;
1672 //Loop through the TRD planes
1673 for (Int_t jplane = 0; jplane < kNPlanes; jplane++) {
1674 // GET TRACKLET OR BUILT IT
1675 Int_t iplane = up ? jplane : kNPlanes - 1 - jplane;
1677 if(!(ptrTracklet = &tracklets[iplane])) continue;
1679 if(!(ptrTracklet = track->GetTracklet(iplane))){
1680 /*AliTRDtrackerV1 *tracker = NULL;
1681 if(!(tracker = dynamic_cast<AliTRDtrackerV1*>( AliTRDrecoParam:Tracker()))) continue;
1682 ptrTracklet = new(&tracklet) AliTRDseedV1(iplane);
1683 if(!tracker->MakeTracklet(ptrTracklet, track)) */
1687 if(!ptrTracklet->IsOK()) continue;
1689 Double_t x = ptrTracklet->GetX0();
1692 //don't do anything if next marker is after next update point.
1693 if((up?-1:1) * (points[ip].GetX() - x) - fgkMaxStep < 0) break;
1694 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1696 Double_t xyz[3]; // should also get the covariance
1698 track->Global2LocalPosition(xyz, track->GetAlpha());
1699 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1702 // printf("plane[%d] tracklet[%p] x[%f]\n", iplane, ptrTracklet, x);
1704 // Propagate closer to the next update point
1705 if(((up?-1:1) * (x - track->GetX()) + fgkMaxStep < 0) && !PropagateToX(*track, x + (up?-1:1)*fgkMaxStep, fgkMaxStep)) return -1.;
1707 if(!AdjustSector(track)) return -1;
1708 if(TMath::Abs(track->GetSnp()) > fgkMaxSnp) return -1;
1710 //load tracklet to the tracker and the track
1712 if((index = FindTracklet(ptrTracklet)) < 0){
1713 ptrTracklet = SetTracklet(&tracklet);
1714 index = fTracklets->GetEntriesFast()-1;
1716 track->SetTracklet(ptrTracklet, index);*/
1719 // register tracklet to track with tracklet creation !!
1720 // PropagateBack : loaded tracklet to the tracker and update index
1721 // RefitInward : update index
1722 // MakeTrack : loaded tracklet to the tracker and update index
1723 if(!tracklets) track->SetTracklet(ptrTracklet, -1);
1726 //Calculate the mean material budget along the path inside the chamber
1727 Double_t xyz0[3]; track->GetXYZ(xyz0);
1728 Double_t alpha = track->GetAlpha();
1729 Double_t xyz1[3], y, z;
1730 if(!track->GetProlongation(x, y, z)) return -1;
1731 xyz1[0] = x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
1732 xyz1[1] = +x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
1734 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
1736 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param) <=0.) break;
1737 Double_t xrho = param[0]*param[4]; // density*length
1738 Double_t xx0 = param[1]; // radiation length
1740 //Propagate the track
1741 track->PropagateTo(x, xx0, xrho);
1742 if (!AdjustSector(track)) break;
1745 Double_t cov[3]; ptrTracklet->GetCovAt(x, cov);
1746 Double_t p[2] = { ptrTracklet->GetY(), ptrTracklet->GetZ()};
1747 Double_t chi2 = ((AliExternalTrackParam*)track)->GetPredictedChi2(p, cov);
1748 if(chi2<1e+10) track->Update(p, cov, chi2);
1751 //Reset material budget if 2 consecutive gold
1752 if(iplane>0 && track->GetTracklet(iplane-1) && ptrTracklet->GetN() + track->GetTracklet(iplane-1)->GetN() > 20) track->SetBudget(2, 0.);
1753 } // end planes loop
1757 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1759 Double_t xyz[3]; // should also get the covariance
1761 track->Global2LocalPosition(xyz, track->GetAlpha());
1762 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1766 return track->GetChi2();
1769 //_________________________________________________________________________
1770 Float_t AliTRDtrackerV1::CalculateChi2Z(AliTRDseedV1 *tracklets, Double_t offset, Double_t slope, Double_t xref)
1773 // Calculates the chi2-value of the track in z-Direction including tilting pad correction.
1774 // A linear dependence on the x-value serves as a model.
1775 // The parameters are related to the tilted Riemann fit.
1776 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
1777 // - the offset for the reference x
1779 // - the reference x position
1780 // Output: - The Chi2 value of the track in z-Direction
1782 Float_t chi2Z = 0, nLayers = 0;
1783 for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNlayer; iLayer++) {
1784 if(!tracklets[iLayer].IsOK()) continue;
1785 Double_t z = offset + slope * (tracklets[iLayer].GetX0() - xref);
1786 chi2Z += TMath::Abs(tracklets[iLayer].GetZfit(0) - z);
1789 chi2Z /= TMath::Max((nLayers - 3.0),1.0);
1793 //_____________________________________________________________________________
1794 Int_t AliTRDtrackerV1::PropagateToX(AliTRDtrackV1 &t, Double_t xToGo, Double_t maxStep)
1797 // Starting from current X-position of track <t> this function
1798 // extrapolates the track up to radial position <xToGo>.
1799 // Returns 1 if track reaches the plane, and 0 otherwise
1802 const Double_t kEpsilon = 0.00001;
1804 // Current track X-position
1805 Double_t xpos = t.GetX();
1807 // Direction: inward or outward
1808 Double_t dir = (xpos < xToGo) ? 1.0 : -1.0;
1810 while (((xToGo - xpos) * dir) > kEpsilon) {
1819 // The next step size
1820 Double_t step = dir * TMath::Min(TMath::Abs(xToGo-xpos),maxStep);
1822 // Get the global position of the starting point
1825 // X-position after next step
1828 // Get local Y and Z at the X-position of the next step
1829 if(t.GetProlongation(x,y,z)<0) return 0; // No prolongation possible
1831 // The global position of the end point of this prolongation step
1832 xyz1[0] = x * TMath::Cos(t.GetAlpha()) - y * TMath::Sin(t.GetAlpha());
1833 xyz1[1] = +x * TMath::Sin(t.GetAlpha()) + y * TMath::Cos(t.GetAlpha());
1836 // Calculate the mean material budget between start and
1837 // end point of this prolongation step
1838 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param)<=0.) return 0;
1840 // Propagate the track to the X-position after the next step
1841 if (!t.PropagateTo(x, param[1], param[0]*param[4])) return 0;
1843 // Rotate the track if necessary
1846 // New track X-position
1856 //_____________________________________________________________________________
1857 Int_t AliTRDtrackerV1::ReadClusters(TClonesArray* &array, TTree *clusterTree) const
1860 // Reads AliTRDclusters from the file.
1861 // The names of the cluster tree and branches
1862 // should match the ones used in AliTRDclusterizer::WriteClusters()
1865 Int_t nsize = Int_t(clusterTree->GetTotBytes() / (sizeof(AliTRDcluster)));
1866 TObjArray *clusterArray = new TObjArray(nsize+1000);
1868 TBranch *branch = clusterTree->GetBranch("TRDcluster");
1870 AliError("Can't get the branch !");
1873 branch->SetAddress(&clusterArray);
1876 Float_t nclusters = fkRecoParam->GetNClusters();
1877 if(fkReconstructor->IsHLT()) nclusters /= AliTRDgeometry::kNsector;
1878 array = new TClonesArray("AliTRDcluster", Int_t(nclusters));
1879 array->SetOwner(kTRUE);
1882 // Loop through all entries in the tree
1883 Int_t nEntries = (Int_t) clusterTree->GetEntries();
1886 AliTRDcluster *c = NULL;
1887 for (Int_t iEntry = 0; iEntry < nEntries; iEntry++) {
1889 nbytes += clusterTree->GetEvent(iEntry);
1891 // Get the number of points in the detector
1892 Int_t nCluster = clusterArray->GetEntriesFast();
1893 for (Int_t iCluster = 0; iCluster < nCluster; iCluster++) {
1894 if(!(c = (AliTRDcluster *) clusterArray->UncheckedAt(iCluster))) continue;
1895 new((*fClusters)[ncl++]) AliTRDcluster(*c);
1896 delete (clusterArray->RemoveAt(iCluster));
1900 delete clusterArray;
1905 //_____________________________________________________________________________
1906 Int_t AliTRDtrackerV1::LoadClusters(TTree *cTree)
1909 // Fills clusters into TRD tracking sectors
1912 fkRecoParam = fkReconstructor->GetRecoParam(); // load reco param for this event
1914 if(!fkReconstructor->IsWritingClusters()){
1915 fClusters = AliTRDReconstructor::GetClusters();
1917 if (ReadClusters(fClusters, cTree)) {
1918 AliError("Problem with reading the clusters !");
1924 if(!fClusters || !fClusters->GetEntriesFast()){
1925 AliInfo("No TRD clusters");
1930 BuildTrackingContainers();
1932 //Int_t ncl = fClusters->GetEntriesFast();
1933 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1938 //_____________________________________________________________________________
1939 Int_t AliTRDtrackerV1::LoadClusters(TClonesArray * const clusters)
1942 // Fills clusters into TRD tracking sectors
1943 // Function for use in the HLT
1945 if(!clusters || !clusters->GetEntriesFast()){
1946 AliInfo("No TRD clusters");
1950 fClusters = clusters;
1953 fkRecoParam = fkReconstructor->GetRecoParam(); // load reco param for this event
1954 BuildTrackingContainers();
1956 //Int_t ncl = fClusters->GetEntriesFast();
1957 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1963 //____________________________________________________________________
1964 Int_t AliTRDtrackerV1::BuildTrackingContainers()
1966 // Building tracking containers for clusters
1968 Int_t nin =0, icl = fClusters->GetEntriesFast();
1970 AliTRDcluster *c = (AliTRDcluster *) fClusters->UncheckedAt(icl);
1971 if(c->IsInChamber()) nin++;
1972 if(fkReconstructor->IsHLT()) c->SetRPhiMethod(AliTRDcluster::kCOG);
1973 Int_t detector = c->GetDetector();
1974 Int_t sector = fGeom->GetSector(detector);
1975 Int_t stack = fGeom->GetStack(detector);
1976 Int_t layer = fGeom->GetLayer(detector);
1978 fTrSec[sector].GetChamber(stack, layer, kTRUE)->InsertCluster(c, icl);
1981 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
1982 for(int isector =0; isector<AliTRDgeometry::kNsector; isector++){
1983 if(!fTrSec[isector].GetNChambers()) continue;
1984 fTrSec[isector].Init(fkReconstructor, cal);
1992 //____________________________________________________________________
1993 void AliTRDtrackerV1::UnloadClusters()
1996 // Clears the arrays of clusters and tracks. Resets sectors and timebins
1997 // If option "force" is also set the containers are also deleted. This is useful
2002 if(HasRemoveContainers()){delete fTracks; fTracks = NULL;}
2005 fTracklets->Delete();
2006 if(HasRemoveContainers()){delete fTracklets; fTracklets = NULL;}
2009 if(IsClustersOwner()) fClusters->Delete();
2011 // save clusters array in the reconstructor for further use.
2012 if(!fkReconstructor->IsWritingClusters()){
2013 AliTRDReconstructor::SetClusters(fClusters);
2014 SetClustersOwner(kFALSE);
2015 } else AliTRDReconstructor::SetClusters(NULL);
2018 for (int i = 0; i < AliTRDgeometry::kNsector; i++) fTrSec[i].Clear();
2020 // Increment the Event Number
2021 AliTRDtrackerDebug::SetEventNumber(AliTRDtrackerDebug::GetEventNumber() + 1);
2024 // //____________________________________________________________________
2025 // void AliTRDtrackerV1::UseClusters(const AliKalmanTrack *t, Int_t) const
2027 // const AliTRDtrackV1 *track = dynamic_cast<const AliTRDtrackV1*>(t);
2028 // if(!track) return;
2030 // AliTRDseedV1 *tracklet = NULL;
2031 // for(Int_t ily=AliTRDgeometry::kNlayer; ily--;){
2032 // if(!(tracklet = track->GetTracklet(ily))) continue;
2033 // AliTRDcluster *c = NULL;
2034 // for(Int_t ic=AliTRDseed::kNclusters; ic--;){
2035 // if(!(c=tracklet->GetClusters(ic))) continue;
2042 //_____________________________________________________________________________
2043 Bool_t AliTRDtrackerV1::AdjustSector(AliTRDtrackV1 *const track)
2046 // Rotates the track when necessary
2049 Double_t alpha = AliTRDgeometry::GetAlpha();
2050 Double_t y = track->GetY();
2051 Double_t ymax = track->GetX()*TMath::Tan(0.5*alpha);
2054 if (!track->Rotate( alpha)) {
2058 else if (y < -ymax) {
2059 if (!track->Rotate(-alpha)) {
2069 //____________________________________________________________________
2070 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(AliTRDtrackV1 *const track, Int_t p, Int_t &idx)
2072 // Find tracklet for TRD track <track>
2081 // Detailed description
2083 idx = track->GetTrackletIndex(p);
2084 AliTRDseedV1 *tracklet = (idx<0) ? NULL : (AliTRDseedV1*)fTracklets->UncheckedAt(idx);
2089 //____________________________________________________________________
2090 AliTRDseedV1* AliTRDtrackerV1::SetTracklet(const AliTRDseedV1 * const tracklet)
2092 // Add this tracklet to the list of tracklets stored in the tracker
2095 // - tracklet : pointer to the tracklet to be added to the list
2098 // - the index of the new tracklet in the tracker tracklets list
2100 // Detailed description
2101 // Build the tracklets list if it is not yet created (late initialization)
2102 // and adds the new tracklet to the list.
2105 fTracklets = new TClonesArray("AliTRDseedV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2106 fTracklets->SetOwner(kTRUE);
2108 Int_t nentries = fTracklets->GetEntriesFast();
2109 return new ((*fTracklets)[nentries]) AliTRDseedV1(*tracklet);
2112 //____________________________________________________________________
2113 AliTRDtrackV1* AliTRDtrackerV1::SetTrack(const AliTRDtrackV1 * const track)
2115 // Add this track to the list of tracks stored in the tracker
2118 // - track : pointer to the track to be added to the list
2121 // - the pointer added
2123 // Detailed description
2124 // Build the tracks list if it is not yet created (late initialization)
2125 // and adds the new track to the list.
2128 fTracks = new TClonesArray("AliTRDtrackV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2129 fTracks->SetOwner(kTRUE);
2131 Int_t nentries = fTracks->GetEntriesFast();
2132 return new ((*fTracks)[nentries]) AliTRDtrackV1(*track);
2137 //____________________________________________________________________
2138 Int_t AliTRDtrackerV1::Clusters2TracksSM(Int_t sector, AliESDEvent *esd)
2141 // Steer tracking for one SM.
2144 // sector : Array of (SM) propagation layers containing clusters
2145 // esd : The current ESD event. On output it contains the also
2146 // the ESD (TRD) tracks found in this SM.
2149 // Number of tracks found in this TRD supermodule.
2151 // Detailed description
2153 // 1. Unpack AliTRDpropagationLayers objects for each stack.
2154 // 2. Launch stack tracking.
2155 // See AliTRDtrackerV1::Clusters2TracksStack() for details.
2156 // 3. Pack results in the ESD event.
2160 Int_t nChambers = 0;
2161 AliTRDtrackingChamber **stack = NULL, *chamber = NULL;
2162 for(int istack = 0; istack<AliTRDgeometry::kNstack; istack++){
2163 if(!(stack = fTrSec[sector].GetStack(istack))) continue;
2165 for(int ilayer=0; ilayer<AliTRDgeometry::kNlayer; ilayer++){
2166 if(!(chamber = stack[ilayer])) continue;
2167 if(chamber->GetNClusters() < fgNTimeBins * fkRecoParam->GetFindableClusters()) continue;
2169 //AliInfo(Form("sector %d stack %d layer %d clusters %d", sector, istack, ilayer, chamber->GetNClusters()));
2171 if(nChambers < 4) continue;
2172 //AliInfo(Form("Doing stack %d", istack));
2173 nTracks += Clusters2TracksStack(stack, fTracksESD);
2175 if(nTracks) AliDebug(2, Form("Number of tracks: SM_%02d[%d]", sector, nTracks));
2177 for(int itrack=0; itrack<nTracks; itrack++){
2178 AliESDtrack *esdTrack((AliESDtrack*)(fTracksESD->operator[](itrack)));
2179 Int_t id = esd->AddTrack(esdTrack);
2181 // set ESD id to stand alone TRD tracks
2182 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2183 esdTrack=esd->GetTrack(id);
2184 TObject *o(NULL); Int_t ic(0);
2185 AliTRDtrackV1 *calibTrack(NULL);
2186 while((o = esdTrack->GetCalibObject(ic++))){
2187 if(!(calibTrack = dynamic_cast<AliTRDtrackV1*>(o))) continue;
2188 calibTrack->SetESDid(esdTrack->GetID());
2194 // Reset Track and Candidate Number
2195 AliTRDtrackerDebug::SetCandidateNumber(0);
2196 AliTRDtrackerDebug::SetTrackNumber(0);
2198 // delete ESD tracks in the array
2199 fTracksESD->Delete();
2203 //____________________________________________________________________
2204 Int_t AliTRDtrackerV1::Clusters2TracksStack(AliTRDtrackingChamber **stack, TClonesArray * const esdTrackList)
2207 // Make tracks in one TRD stack.
2210 // layer : Array of stack propagation layers containing clusters
2211 // esdTrackList : Array of ESD tracks found by the stand alone tracker.
2212 // On exit the tracks found in this stack are appended.
2215 // Number of tracks found in this stack.
2217 // Detailed description
2219 // 1. Find the 3 most useful seeding chambers. See BuildSeedingConfigs() for details.
2220 // 2. Steer AliTRDtrackerV1::MakeSeeds() for 3 seeding layer configurations.
2221 // See AliTRDtrackerV1::MakeSeeds() for more details.
2222 // 3. Arrange track candidates in decreasing order of their quality
2223 // 4. Classify tracks in 5 categories according to:
2224 // a) number of layers crossed
2226 // 5. Sign clusters by tracks in decreasing order of track quality
2227 // 6. Build AliTRDtrack out of seeding tracklets
2229 // 8. Build ESD track and register it to the output list
2232 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
2233 AliTRDtrackingChamber *chamber = NULL;
2234 AliTRDtrackingChamber **ci = NULL;
2235 AliTRDseedV1 sseed[kMaxTracksStack*6]; // to be initialized
2236 Int_t pars[4]; // MakeSeeds parameters
2238 //Double_t alpha = AliTRDgeometry::GetAlpha();
2239 //Double_t shift = .5 * alpha;
2240 Int_t configs[kNConfigs];
2242 // Purge used clusters from the containers
2244 for(Int_t ic = kNPlanes; ic--; ci++){
2245 if(!(*ci)) continue;
2249 // Build initial seeding configurations
2250 Double_t quality = BuildSeedingConfigs(stack, configs);
2251 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2252 AliInfo(Form("Plane config %d %d %d Quality %f"
2253 , configs[0], configs[1], configs[2], quality));
2257 // Initialize contors
2258 Int_t ntracks, // number of TRD track candidates
2259 ntracks1, // number of registered TRD tracks/iter
2260 ntracks2 = 0; // number of all registered TRD tracks in stack
2264 Int_t ic = 0; ci = &stack[0];
2265 while(ic<kNPlanes && !(*ci)){ic++; ci++;}
2266 if(!(*ci)) return ntracks2;
2267 Int_t istack = fGeom->GetStack((*ci)->GetDetector());
2270 // Loop over seeding configurations
2271 ntracks = 0; ntracks1 = 0;
2272 for (Int_t iconf = 0; iconf<3; iconf++) {
2273 pars[0] = configs[iconf];
2276 ntracks = MakeSeeds(stack, &sseed[6*ntracks], pars);
2277 //AliInfo(Form("Number of Tracks after iteration step %d: %d\n", iconf, ntracks));
2278 if(ntracks == kMaxTracksStack) break;
2280 AliDebug(2, Form("Candidate TRD tracks %d in iteration %d.", ntracks, fSieveSeeding));
2284 // Sort the seeds according to their quality
2285 Int_t sort[kMaxTracksStack];
2286 TMath::Sort(ntracks, fTrackQuality, sort, kTRUE);
2288 // Initialize number of tracks so far and logic switches
2289 Int_t ntracks0 = esdTrackList->GetEntriesFast();
2290 Bool_t signedTrack[kMaxTracksStack];
2291 Bool_t fakeTrack[kMaxTracksStack];
2292 for (Int_t i=0; i<ntracks; i++){
2293 signedTrack[i] = kFALSE;
2294 fakeTrack[i] = kFALSE;
2296 //AliInfo("Selecting track candidates ...");
2298 // Sieve clusters in decreasing order of track quality
2299 Double_t trackParams[7];
2300 // AliTRDseedV1 *lseed = NULL;
2301 Int_t jSieve = 0, candidates;
2303 //AliInfo(Form("\t\tITER = %i ", jSieve));
2305 // Check track candidates
2307 for (Int_t itrack = 0; itrack < ntracks; itrack++) {
2308 Int_t trackIndex = sort[itrack];
2309 if (signedTrack[trackIndex] || fakeTrack[trackIndex]) continue;
2312 // Calculate track parameters from tracklets seeds
2317 for (Int_t jLayer = 0; jLayer < kNPlanes; jLayer++) {
2318 Int_t jseed = kNPlanes*trackIndex+jLayer;
2319 if(!sseed[jseed].IsOK()) continue;
2320 if (TMath::Abs(sseed[jseed].GetYref(0) / sseed[jseed].GetX0()) < 0.158) findable++;
2321 // TODO here we get a sig fault which should never happen !
2322 sseed[jseed].UpdateUsed();
2323 ncl += sseed[jseed].GetN2();
2324 nused += sseed[jseed].GetNUsed();
2328 // Filter duplicated tracks
2330 //printf("Skip %d nused %d\n", trackIndex, nused);
2331 fakeTrack[trackIndex] = kTRUE;
2334 if (ncl>0 && Float_t(nused)/ncl >= .25){
2335 //printf("Skip %d nused/ncl >= .25\n", trackIndex);
2336 fakeTrack[trackIndex] = kTRUE;
2341 Bool_t skip = kFALSE;
2344 if(nlayers < 6) {skip = kTRUE; break;}
2345 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2349 if(nlayers < findable){skip = kTRUE; break;}
2350 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -4.){skip = kTRUE; break;}
2354 if ((nlayers == findable) || (nlayers == 6)) { skip = kTRUE; break;}
2355 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -6.0){skip = kTRUE; break;}
2359 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2363 if (nlayers == 3){skip = kTRUE; break;}
2364 //if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) - nused/(nlayers-3.0) < -15.0){skip = kTRUE; break;}
2369 AliDebug(4, Form("REJECTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2371 } else AliDebug(4, Form("ACCEPTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2373 signedTrack[trackIndex] = kTRUE;
2375 // Build track parameters
2376 AliTRDseedV1 *lseed =&sseed[trackIndex*6];
2378 while(idx<3 && !lseed->IsOK()) {
2382 Double_t x = lseed->GetX0();// - 3.5;
2383 trackParams[0] = x; //NEW AB
2384 trackParams[1] = lseed->GetYref(0); // lseed->GetYat(x);
2385 trackParams[2] = lseed->GetZref(0); // lseed->GetZat(x);
2386 trackParams[3] = TMath::Sin(TMath::ATan(lseed->GetYref(1)));
2387 trackParams[4] = lseed->GetZref(1) / TMath::Sqrt(1. + lseed->GetYref(1) * lseed->GetYref(1));
2388 trackParams[5] = lseed->GetC();
2389 Int_t ich = 0; while(!(chamber = stack[ich])) ich++;
2390 trackParams[6] = fGeom->GetSector(chamber->GetDetector());/* *alpha+shift; // Supermodule*/
2392 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 1 && fkReconstructor->IsDebugStreaming()){
2393 //AliInfo(Form("Track %d [%d] nlayers %d trackQuality = %e nused %d, yref = %3.3f", itrack, trackIndex, nlayers, fTrackQuality[trackIndex], nused, trackParams[1]));
2395 AliTRDseedV1 *dseed[6];
2396 for(Int_t iseed = AliTRDgeometry::kNlayer; iseed--;) dseed[iseed] = new AliTRDseedV1(lseed[iseed]);
2398 //Int_t eventNrInFile = esd->GetEventNumberInFile();
2399 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2400 Int_t trackNumber = AliTRDtrackerDebug::GetTrackNumber();
2401 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2402 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2403 cstreamer << "Clusters2TracksStack"
2404 << "EventNumber=" << eventNumber
2405 << "TrackNumber=" << trackNumber
2406 << "CandidateNumber=" << candidateNumber
2407 << "Iter=" << fSieveSeeding
2408 << "Like=" << fTrackQuality[trackIndex]
2409 << "S0.=" << dseed[0]
2410 << "S1.=" << dseed[1]
2411 << "S2.=" << dseed[2]
2412 << "S3.=" << dseed[3]
2413 << "S4.=" << dseed[4]
2414 << "S5.=" << dseed[5]
2415 << "p0=" << trackParams[0]
2416 << "p1=" << trackParams[1]
2417 << "p2=" << trackParams[2]
2418 << "p3=" << trackParams[3]
2419 << "p4=" << trackParams[4]
2420 << "p5=" << trackParams[5]
2421 << "p6=" << trackParams[6]
2423 << "NLayers=" << nlayers
2424 << "Findable=" << findable
2425 << "NUsed=" << nused
2429 AliTRDtrackV1 *track = MakeTrack(&sseed[trackIndex*kNPlanes], trackParams);
2431 AliDebug(1, "Track building failed.");
2435 //AliInfo("End of MakeTrack()");
2436 AliESDtrack *esdTrack = new ((*esdTrackList)[ntracks0++]) AliESDtrack();
2437 esdTrack->UpdateTrackParams(track, AliESDtrack::kTRDout);
2438 esdTrack->SetLabel(track->GetLabel());
2439 track->UpdateESDtrack(esdTrack);
2440 // write ESD-friends if neccessary
2441 if (fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2442 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(*track);
2443 calibTrack->SetOwner();
2444 esdTrack->AddCalibObject(calibTrack);
2447 AliTRDtrackerDebug::SetTrackNumber(AliTRDtrackerDebug::GetTrackNumber() + 1);
2451 } while(jSieve<5 && candidates); // end track candidates sieve
2452 if(!ntracks1) break;
2454 // increment counters
2455 ntracks2 += ntracks1;
2457 if(fkReconstructor->IsHLT()) break;
2460 // Rebuild plane configurations and indices taking only unused clusters into account
2461 quality = BuildSeedingConfigs(stack, configs);
2462 if(quality < 1.E-7) break; //fkReconstructor->GetRecoParam() ->GetPlaneQualityThreshold()) break;
2464 for(Int_t ip = 0; ip < kNPlanes; ip++){
2465 if(!(chamber = stack[ip])) continue;
2466 chamber->Build(fGeom, cal);//Indices(fSieveSeeding);
2469 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2470 AliInfo(Form("Sieve level %d Plane config %d %d %d Quality %f", fSieveSeeding, configs[0], configs[1], configs[2], quality));
2472 } while(fSieveSeeding<10); // end stack clusters sieve
2476 //AliInfo(Form("Registered TRD tracks %d in stack %d.", ntracks2, pars[1]));
2481 //___________________________________________________________________
2482 Double_t AliTRDtrackerV1::BuildSeedingConfigs(AliTRDtrackingChamber **stack, Int_t *configs)
2485 // Assign probabilities to chambers according to their
2486 // capability of producing seeds.
2490 // layers : Array of stack propagation layers for all 6 chambers in one stack
2491 // configs : On exit array of configuration indexes (see GetSeedingConfig()
2492 // for details) in the decreasing order of their seeding probabilities.
2496 // Return top configuration quality
2498 // Detailed description:
2500 // To each chamber seeding configuration (see GetSeedingConfig() for
2501 // the list of all configurations) one defines 2 quality factors:
2502 // - an apriori topological quality (see GetSeedingConfig() for details) and
2503 // - a data quality based on the uniformity of the distribution of
2504 // clusters over the x range (time bins population). See CookChamberQA() for details.
2505 // The overall chamber quality is given by the product of this 2 contributions.
2508 Double_t chamberQ[kNPlanes];memset(chamberQ, 0, kNPlanes*sizeof(Double_t));
2509 AliTRDtrackingChamber *chamber = NULL;
2510 for(int iplane=0; iplane<kNPlanes; iplane++){
2511 if(!(chamber = stack[iplane])) continue;
2512 chamberQ[iplane] = (chamber = stack[iplane]) ? chamber->GetQuality() : 0.;
2515 Double_t tconfig[kNConfigs];memset(tconfig, 0, kNConfigs*sizeof(Double_t));
2516 Int_t planes[] = {0, 0, 0, 0};
2517 for(int iconf=0; iconf<kNConfigs; iconf++){
2518 GetSeedingConfig(iconf, planes);
2519 tconfig[iconf] = fgTopologicQA[iconf];
2520 for(int iplane=0; iplane<4; iplane++) tconfig[iconf] *= chamberQ[planes[iplane]];
2523 TMath::Sort((Int_t)kNConfigs, tconfig, configs, kTRUE);
2524 // AliInfo(Form("q[%d] = %f", configs[0], tconfig[configs[0]]));
2525 // AliInfo(Form("q[%d] = %f", configs[1], tconfig[configs[1]]));
2526 // AliInfo(Form("q[%d] = %f", configs[2], tconfig[configs[2]]));
2528 return tconfig[configs[0]];
2531 //____________________________________________________________________
2532 Int_t AliTRDtrackerV1::MakeSeeds(AliTRDtrackingChamber **stack, AliTRDseedV1 * const sseed, const Int_t * const ipar)
2535 // Seed tracklets and build candidate TRD tracks. The procedure is used during barrel tracking to account for tracks which are
2536 // either missed by TPC prolongation or conversions inside the TRD volume.
2537 // For stand alone tracking the procedure is used to estimate all tracks measured by TRD.
2540 // layers : Array of stack propagation layers containing clusters
2541 // sseed : Array of empty tracklet seeds. On exit they are filled.
2542 // ipar : Control parameters:
2543 // ipar[0] -> seeding chambers configuration
2544 // ipar[1] -> stack index
2545 // ipar[2] -> number of track candidates found so far
2548 // Number of tracks candidates found.
2550 // The following steps are performed:
2551 // 1. Build seeding layers by collapsing all time bins from each of the four seeding chambers along the
2552 // radial coordinate. See AliTRDtrackingChamber::GetSeedingLayer() for details. The chambers selection for seeding
2553 // is described in AliTRDtrackerV1::Clusters2TracksStack().
2554 // 2. Using the seeding clusters from the seeding layer (step 1) build combinatorics using the following algorithm:
2555 // - for each seeding cluster in the lower seeding layer find
2556 // - all seeding clusters in the upper seeding layer inside a road defined by a given phi angle. The angle
2557 // is calculated on the minimum pt of tracks from vertex accesible to the stand alone tracker.
2558 // - for each pair of two extreme seeding clusters select middle upper cluster using roads defined externally by the
2560 // - select last seeding cluster as the nearest to the linear approximation of the track described by the first three
2561 // seeding clusters.
2562 // The implementation of road calculation and cluster selection can be found in the functions AliTRDchamberTimeBin::BuildCond()
2563 // and AliTRDchamberTimeBin::GetClusters().
2564 // 3. Helix fit of the seeding clusters set. (see AliTRDtrackerFitter::FitRieman(AliTRDcluster**)). No tilt correction is
2565 // performed at this level
2566 // 4. Initialize seeding tracklets in the seeding chambers.
2567 // 5. *Filter 0* Chi2 cut on the Y and Z directions. The threshold is set externally by the reco params.
2568 // 6. Attach (true) clusters to seeding tracklets (see AliTRDseedV1::AttachClusters()) and fit tracklet (see
2569 // AliTRDseedV1::Fit()). The number of used clusters used by current seeds should not exceed ... (25).
2570 // 7. *Filter 1* Check if all 4 seeding tracklets are correctly constructed.
2571 // 8. Helix fit of the clusters from the seeding tracklets with tilt correction. Refit tracklets using the new
2572 // approximation of the track.
2573 // 9. *Filter 2* Calculate likelihood of the track. (See AliTRDtrackerV1::CookLikelihood()). The following quantities are
2574 // checked against the Riemann fit:
2575 // - position resolution in y
2576 // - angular resolution in the bending plane
2577 // - likelihood of the number of clusters attached to the tracklet
2578 // 10. Extrapolation of the helix fit to the other 2 chambers *non seeding* chambers:
2579 // - Initialization of extrapolation tracklets with the fit parameters
2580 // - Attach clusters to extrapolated tracklets
2581 // - Helix fit of tracklets
2582 // 11. Improve seeding tracklets quality by reassigning clusters based on the last parameters of the track
2583 // See AliTRDtrackerV1::ImproveSeedQuality() for details.
2584 // 12. Helix fit of all 6 seeding tracklets and chi2 calculation
2585 // 13. Hyperplane fit and track quality calculation. See AliTRDtrackerFitter::FitHyperplane() for details.
2586 // 14. Cooking labels for tracklets. Should be done only for MC
2587 // 15. Register seeds.
2590 // Marian Ivanov <M.Ivanov@gsi.de>
2591 // Alexandru Bercuci <A.Bercuci@gsi.de>
2592 // Markus Fasel <M.Fasel@gsi.de>
2594 AliTRDtrackingChamber *chamber = NULL;
2595 AliTRDcluster *c[kNSeedPlanes] = {NULL, NULL, NULL, NULL}; // initilize seeding clusters
2596 AliTRDseedV1 *cseed = &sseed[0]; // initialize tracklets for first track
2597 Int_t ncl, mcl; // working variable for looping over clusters
2598 Int_t index[AliTRDchamberTimeBin::kMaxClustersLayer], jndex[AliTRDchamberTimeBin::kMaxClustersLayer];
2600 // chi2[0] = tracklet chi2 on the Z direction
2601 // chi2[1] = tracklet chi2 on the R direction
2604 // this should be data member of AliTRDtrack TODO
2605 Double_t seedQuality[kMaxTracksStack];
2607 // unpack control parameters
2608 Int_t config = ipar[0];
2609 Int_t ntracks = ipar[1];
2610 Int_t istack = ipar[2];
2611 Int_t planes[kNSeedPlanes]; GetSeedingConfig(config, planes);
2612 Int_t planesExt[kNPlanes-kNSeedPlanes]; GetExtrapolationConfig(config, planesExt);
2615 // Init chambers geometry
2616 Double_t hL[kNPlanes]; // Tilting angle
2617 Float_t padlength[kNPlanes]; // pad lenghts
2618 Float_t padwidth[kNPlanes]; // pad widths
2619 AliTRDpadPlane *pp = NULL;
2620 for(int iplane=0; iplane<kNPlanes; iplane++){
2621 pp = fGeom->GetPadPlane(iplane, istack);
2622 hL[iplane] = TMath::Tan(TMath::DegToRad()*pp->GetTiltingAngle());
2623 padlength[iplane] = pp->GetLengthIPad();
2624 padwidth[iplane] = pp->GetWidthIPad();
2627 // Init anode wire position for chambers
2628 Double_t x0[kNPlanes], // anode wire position
2629 driftLength = .5*AliTRDgeometry::AmThick() - AliTRDgeometry::DrThick(); // drift length
2630 TGeoHMatrix *matrix = NULL;
2631 Double_t loc[] = {AliTRDgeometry::AnodePos(), 0., 0.};
2632 Double_t glb[] = {0., 0., 0.};
2633 AliTRDtrackingChamber **cIter = &stack[0];
2634 for(int iLayer=0; iLayer<kNPlanes; iLayer++,cIter++){
2635 if(!(*cIter)) continue;
2636 if(!(matrix = fGeom->GetClusterMatrix((*cIter)->GetDetector()))){
2638 x0[iLayer] = fgkX0[iLayer];
2640 matrix->LocalToMaster(loc, glb);
2641 x0[iLayer] = glb[0];
2644 AliDebug(2, Form("Making seeds Stack[%d] Config[%d] Tracks[%d]...", istack, config, ntracks));
2646 // Build seeding layers
2649 for(int isl=0; isl<kNSeedPlanes; isl++){
2650 if(!(chamber = stack[planes[isl]])) continue;
2651 if(!chamber->GetSeedingLayer(fSeedTB[isl], fGeom, fkReconstructor)) continue;
2654 if(nlayers < kNSeedPlanes) return ntracks;
2657 // Start finding seeds
2658 Double_t cond0[4], cond1[4], cond2[4];
2660 while((c[3] = (*fSeedTB[3])[icl++])){
2662 fSeedTB[0]->BuildCond(c[3], cond0, 0);
2663 fSeedTB[0]->GetClusters(cond0, index, ncl);
2664 //printf("Found c[3] candidates 0 %d\n", ncl);
2667 c[0] = (*fSeedTB[0])[index[jcl++]];
2669 Double_t dx = c[3]->GetX() - c[0]->GetX();
2670 Double_t dzdx = (c[3]->GetZ() - c[0]->GetZ())/dx;
2671 Double_t dydx = (c[3]->GetY() - c[0]->GetY())/dx;
2672 fSeedTB[1]->BuildCond(c[0], cond1, 1, dzdx, dydx);
2673 fSeedTB[1]->GetClusters(cond1, jndex, mcl);
2674 //printf("Found c[0] candidates 1 %d\n", mcl);
2678 c[1] = (*fSeedTB[1])[jndex[kcl++]];
2680 fSeedTB[2]->BuildCond(c[1], cond2, 2, dzdx, dydx);
2681 c[2] = fSeedTB[2]->GetNearestCluster(cond2);
2682 //printf("Found c[1] candidate 2 %p\n", c[2]);
2685 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].",
2686 c[0]->GetX(), c[0]->GetY(), c[0]->GetZ(),
2687 c[1]->GetX(), c[1]->GetY(), c[1]->GetZ(),
2688 c[2]->GetX(), c[2]->GetY(), c[2]->GetZ(),
2689 c[3]->GetX(), c[3]->GetY(), c[3]->GetZ()));
2691 for (Int_t il = 0; il < kNPlanes; il++) cseed[il].Reset();
2695 AliTRDseedV1 *tseed = &cseed[0];
2697 for(int iLayer=0; iLayer<kNPlanes; iLayer++, tseed++, cIter++){
2698 Int_t det = (*cIter) ? (*cIter)->GetDetector() : -1;
2699 tseed->SetDetector(det);
2700 tseed->SetTilt(hL[iLayer]);
2701 tseed->SetPadLength(padlength[iLayer]);
2702 tseed->SetPadWidth(padwidth[iLayer]);
2703 tseed->SetReconstructor(fkReconstructor);
2704 tseed->SetX0(det<0 ? fR[iLayer]+driftLength : x0[iLayer]);
2705 tseed->Init(GetRiemanFitter());
2706 tseed->SetStandAlone(kTRUE);
2709 Bool_t isFake = kFALSE;
2710 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2711 if (c[0]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2712 if (c[1]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2713 if (c[2]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2716 for(Int_t l = 0; l < kNSeedPlanes; l++) xpos[l] = fSeedTB[l]->GetX();
2718 for(int il=0; il<4; il++) yref[il] = cseed[planes[il]].GetYref(0);
2719 Int_t ll = c[3]->GetLabel(0);
2720 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2721 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2722 AliRieman *rim = GetRiemanFitter();
2723 TTreeSRedirector &cs0 = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2725 <<"EventNumber=" << eventNumber
2726 <<"CandidateNumber=" << candidateNumber
2727 <<"isFake=" << isFake
2728 <<"config=" << config
2730 <<"chi2z=" << chi2[0]
2731 <<"chi2y=" << chi2[1]
2732 <<"Y2exp=" << cond2[0]
2733 <<"Z2exp=" << cond2[1]
2734 <<"X0=" << xpos[0] //layer[sLayer]->GetX()
2735 <<"X1=" << xpos[1] //layer[sLayer + 1]->GetX()
2736 <<"X2=" << xpos[2] //layer[sLayer + 2]->GetX()
2737 <<"X3=" << xpos[3] //layer[sLayer + 3]->GetX()
2738 <<"yref0=" << yref[0]
2739 <<"yref1=" << yref[1]
2740 <<"yref2=" << yref[2]
2741 <<"yref3=" << yref[3]
2746 <<"Seed0.=" << &cseed[planes[0]]
2747 <<"Seed1.=" << &cseed[planes[1]]
2748 <<"Seed2.=" << &cseed[planes[2]]
2749 <<"Seed3.=" << &cseed[planes[3]]
2750 <<"RiemanFitter.=" << rim
2753 if(chi2[0] > fkRecoParam->GetChi2Z()/*7./(3. - sLayer)*//*iter*/){
2754 AliDebug(3, Form("Filter on chi2Z [%f].", chi2[0]));
2755 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2758 if(chi2[1] > fkRecoParam->GetChi2Y()/*1./(3. - sLayer)*//*iter*/){
2759 AliDebug(3, Form("Filter on chi2Y [%f].", chi2[1]));
2760 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2763 //AliInfo("Passed chi2 filter.");
2765 // try attaching clusters to tracklets
2767 AliTRDcluster *cl = NULL;
2768 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2769 Int_t jLayer = planes[iLayer];
2770 Int_t nNotInChamber = 0;
2771 if(!cseed[jLayer].AttachClusters(stack[jLayer], kTRUE)) continue;
2772 if(/*fkReconstructor->IsHLT()*/kFALSE){
2773 cseed[jLayer].UpdateUsed();
2774 if(!cseed[jLayer].IsOK()) continue;
2776 cseed[jLayer].Fit();
2777 cseed[jLayer].UpdateUsed();
2778 cseed[jLayer].ResetClusterIter();
2779 while((cl = cseed[jLayer].NextCluster())){
2780 if(!cl->IsInChamber()) nNotInChamber++;
2782 //printf("clusters[%d], used[%d], not in chamber[%d]\n", cseed[jLayer].GetN(), cseed[jLayer].GetNUsed(), nNotInChamber);
2783 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
2788 if(mlayers < kNSeedPlanes){
2789 AliDebug(2, Form("Found only %d tracklets out of %d. Skip.", mlayers, kNSeedPlanes));
2790 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2794 // temporary exit door for the HLT
2795 if(fkReconstructor->IsHLT()){
2796 // attach clusters to extrapolation chambers
2797 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2798 Int_t jLayer = planesExt[iLayer];
2799 if(!(chamber = stack[jLayer])) continue;
2800 if(!cseed[jLayer].AttachClusters(chamber, kTRUE)) continue;
2801 cseed[jLayer].Fit();
2803 fTrackQuality[ntracks] = 1.; // dummy value
2805 if(ntracks == kMaxTracksStack) return ntracks;
2811 // Update Seeds and calculate Likelihood
2812 // fit tracklets and cook likelihood
2813 FitTiltedRieman(&cseed[0], kTRUE);
2814 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2815 Int_t jLayer = planes[iLayer];
2816 cseed[jLayer].Fit(kTRUE);
2818 Double_t like = CookLikelihood(&cseed[0], planes); // to be checked
2820 if (TMath::Log(1.E-9 + like) < fkRecoParam->GetTrackLikelihood()){
2821 AliDebug(3, Form("Filter on likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2822 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2825 //AliInfo(Form("Passed likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2827 // book preliminary results
2828 seedQuality[ntracks] = like;
2829 fSeedLayer[ntracks] = config;/*sLayer;*/
2831 // attach clusters to the extrapolation seeds
2833 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2834 Int_t jLayer = planesExt[iLayer];
2835 if(!(chamber = stack[jLayer])) continue;
2837 // fit extrapolated seed
2838 if ((jLayer == 0) && !(cseed[1].IsOK())) continue;
2839 if ((jLayer == 5) && !(cseed[4].IsOK())) continue;
2840 AliTRDseedV1 pseed = cseed[jLayer];
2841 if(!pseed.AttachClusters(chamber, kTRUE)) continue;
2843 cseed[jLayer] = pseed;
2844 FitTiltedRieman(cseed, kTRUE);
2845 cseed[jLayer].Fit(kTRUE);
2849 // AliInfo("Extrapolation done.");
2850 // Debug Stream containing all the 6 tracklets
2851 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2852 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2853 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
2854 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2855 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2856 cstreamer << "MakeSeeds1"
2857 << "EventNumber=" << eventNumber
2858 << "CandidateNumber=" << candidateNumber
2859 << "S0.=" << &cseed[0]
2860 << "S1.=" << &cseed[1]
2861 << "S2.=" << &cseed[2]
2862 << "S3.=" << &cseed[3]
2863 << "S4.=" << &cseed[4]
2864 << "S5.=" << &cseed[5]
2865 << "FitterT.=" << tiltedRieman
2869 if(fkRecoParam->HasImproveTracklets()){
2870 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
2871 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer] = cseed[jLayer];
2873 if(ImproveSeedQuality(stack, cseed) < mlayers+elayers){
2874 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2875 AliDebug(3, "Filter on improve seeds.");
2878 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) cseed[jLayer] = bseed[jLayer];
2881 //AliInfo("Improve seed quality done.");
2883 // fit full track and cook likelihoods
2884 // Double_t curv = FitRieman(&cseed[0], chi2);
2885 // Double_t chi2ZF = chi2[0] / TMath::Max((mlayers - 3.), 1.);
2886 // Double_t chi2RF = chi2[1] / TMath::Max((mlayers - 3.), 1.);
2888 // do the final track fitting (Once with vertex constraint and once without vertex constraint)
2889 Double_t chi2Vals[3];
2890 chi2Vals[0] = FitTiltedRieman(&cseed[0], kTRUE);
2891 if(fkRecoParam->IsVertexConstrained())
2892 chi2Vals[1] = FitTiltedRiemanConstraint(&cseed[0], GetZ()); // Do Vertex Constrained fit if desired
2895 chi2Vals[2] = GetChi2Z(&cseed[0]) / TMath::Max((mlayers - 3.), 1.);
2896 // Chi2 definitions in testing stage
2897 //chi2Vals[2] = GetChi2ZTest(&cseed[0]);
2898 fTrackQuality[ntracks] = CalculateTrackLikelihood(&cseed[0], &chi2Vals[0]);
2899 //AliInfo("Hyperplane fit done\n");
2901 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2902 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2903 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2904 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2905 TLinearFitter *fitterTC = GetTiltedRiemanFitterConstraint();
2906 TLinearFitter *fitterT = GetTiltedRiemanFitter();
2908 for(Int_t iseed = 0; iseed < kNPlanes; iseed++){
2909 ncls += cseed[iseed].IsOK() ? cseed[iseed].GetN2() : 0;
2911 cstreamer << "MakeSeeds2"
2912 << "EventNumber=" << eventNumber
2913 << "CandidateNumber=" << candidateNumber
2914 << "Chi2TR=" << chi2Vals[0]
2915 << "Chi2TC=" << chi2Vals[1]
2916 << "Nlayers=" << mlayers
2917 << "NClusters=" << ncls
2919 << "S0.=" << &cseed[0]
2920 << "S1.=" << &cseed[1]
2921 << "S2.=" << &cseed[2]
2922 << "S3.=" << &cseed[3]
2923 << "S4.=" << &cseed[4]
2924 << "S5.=" << &cseed[5]
2925 << "FitterT.=" << fitterT
2926 << "FitterTC.=" << fitterTC
2931 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2932 if(ntracks == kMaxTracksStack){
2933 AliWarning(Form("Number of seeds reached maximum allowed (%d) in stack.", kMaxTracksStack));
2944 //_____________________________________________________________________________
2945 AliTRDtrackV1* AliTRDtrackerV1::MakeTrack(AliTRDseedV1 * const seeds, Double_t *params)
2948 // Build a TRD track out of tracklet candidates
2951 // seeds : array of tracklets
2952 // params : array of track parameters as they are estimated by stand alone tracker. 7 elements.
2953 // [0] - radial position of the track at reference point
2954 // [1] - y position of the fit at [0]
2955 // [2] - z position of the fit at [0]
2956 // [3] - snp of the first tracklet
2957 // [4] - tgl of the first tracklet
2958 // [5] - curvature of the Riemann fit - 1/pt
2959 // [6] - sector rotation angle
2964 // Initialize the TRD track based on the parameters of the fit and a parametric covariance matrix
2965 // (diagonal with constant variance terms TODO - correct parameterization)
2967 // In case of HLT just register the tracklets in the tracker and return values of the Riemann fit. For the
2968 // offline case perform a full Kalman filter on the already found tracklets (see AliTRDtrackerV1::FollowBackProlongation()
2969 // for details). Do also MC label calculation and PID if propagation successfully.
2972 Double_t alpha = AliTRDgeometry::GetAlpha();
2973 Double_t shift = AliTRDgeometry::GetAlpha()/2.0;
2976 c[ 0] = 0.2; // s^2_y
2977 c[ 1] = 0.0; c[ 2] = 2.0; // s^2_z
2978 c[ 3] = 0.0; c[ 4] = 0.0; c[ 5] = 0.02; // s^2_snp
2979 c[ 6] = 0.0; c[ 7] = 0.0; c[ 8] = 0.0; c[ 9] = 0.1; // s^2_tgl
2980 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
2982 AliTRDtrackV1 track(seeds, ¶ms[1], c, params[0], params[6]*alpha+shift);
2983 track.PropagateTo(params[0]-5.0);
2984 AliTRDseedV1 *ptrTracklet = NULL;
2986 // skip Kalman filter for HLT
2987 if(/*fkReconstructor->IsHLT()*/kFALSE){
2988 for (Int_t jLayer = 0; jLayer < AliTRDgeometry::kNlayer; jLayer++) {
2989 track.UnsetTracklet(jLayer);
2990 ptrTracklet = &seeds[jLayer];
2991 if(!ptrTracklet->IsOK()) continue;
2992 if(TMath::Abs(ptrTracklet->GetYref(1) - ptrTracklet->GetYfit(1)) >= .2) continue; // check this condition with Marian
2993 ptrTracklet = SetTracklet(ptrTracklet);
2994 ptrTracklet->UseClusters();
2995 track.SetTracklet(ptrTracklet, fTracklets->GetEntriesFast()-1);
2997 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
2998 ptrTrack->CookPID();
2999 ptrTrack->CookLabel(.9);
3000 ptrTrack->SetReconstructor(fkReconstructor);
3004 // prevent the error message in AliTracker::MeanMaterialBudget: "start point out of geometry"
3005 if(TMath::Abs(track.GetX()) + TMath::Abs(track.GetY()) + TMath::Abs(track.GetZ()) > 10000)
3008 track.ResetCovariance(1);
3009 Int_t nc = TMath::Abs(FollowBackProlongation(track));
3010 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) > 5 && fkReconstructor->IsDebugStreaming()){
3011 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3012 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3013 Double_t p[5]; // Track Params for the Debug Stream
3014 track.GetExternalParameters(params[0], p);
3015 TTreeSRedirector &cs = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3017 << "EventNumber=" << eventNumber
3018 << "CandidateNumber=" << candidateNumber
3020 << "X=" << params[0]
3026 << "Yin=" << params[1]
3027 << "Zin=" << params[2]
3028 << "snpin=" << params[3]
3029 << "tndin=" << params[4]
3030 << "crvin=" << params[5]
3031 << "track.=" << &track
3034 if (nc < 30) return NULL;
3036 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
3037 ptrTrack->SetReconstructor(fkReconstructor);
3038 ptrTrack->CookLabel(.9);
3040 // computes PID for track
3041 ptrTrack->CookPID();
3042 // update calibration references using this track
3043 AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance();
3045 AliInfo("Could not get Calibra instance\n");
3046 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(ptrTrack);
3052 //____________________________________________________________________
3053 Int_t AliTRDtrackerV1::ImproveSeedQuality(AliTRDtrackingChamber **stack, AliTRDseedV1 *cseed)
3056 // Sort tracklets according to "quality" and try to "improve" the first 4 worst
3059 // layers : Array of propagation layers for a stack/supermodule
3060 // cseed : Array of 6 seeding tracklets which has to be improved
3063 // cssed : Improved seeds
3065 // Detailed description
3067 // Iterative procedure in which new clusters are searched for each
3068 // tracklet seed such that the seed quality (see AliTRDseed::GetQuality())
3069 // can be maximized. If some optimization is found the old seeds are replaced.
3074 // make a local working copy
3075 AliTRDtrackingChamber *chamber = NULL;
3076 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
3078 Float_t quality(0.),
3079 lQuality[] = {1.e3, 1.e3, 1.e3, 1.e3, 1.e3, 1.e3};
3081 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;){
3082 bseed[jLayer] = cseed[jLayer];
3083 if(!bseed[jLayer].IsOK()) continue;
3085 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3086 quality += lQuality[jLayer];
3088 Float_t chi2 = FitTiltedRieman(bseed, kTRUE);
3090 for (Int_t iter = 0; iter < 4; iter++) {
3091 AliDebug(2, Form("Iter[%d] Q[%f] chi2[%f]", iter, quality, chi2));
3093 // Try better cluster set
3094 Int_t nLayers(0); Float_t qualitynew(0.);
3096 TMath::Sort(Int_t(AliTRDgeometry::kNlayer), lQuality, indexes, kFALSE);
3097 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) {
3098 Int_t bLayer = indexes[jLayer];
3099 bseed[bLayer].Reset("c");
3100 if(!(chamber = stack[bLayer])) continue;
3101 if(!bseed[bLayer].AttachClusters(chamber, kTRUE)) continue;
3102 bseed[bLayer].Fit(kTRUE);
3103 if(!bseed[bLayer].IsOK()) continue;
3105 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3106 qualitynew += lQuality[jLayer];
3108 if(rLayers > nLayers){
3109 AliDebug(1, Form("Lost %d tracklets while improving.", rLayers-nLayers));
3111 } else rLayers=nLayers;
3113 if(qualitynew >= quality){
3114 AliDebug(4, Form("Quality worsen in iter[%d].", iter));
3116 } else quality = qualitynew;
3118 // try improve track parameters
3119 AliTRDseedV1 tseed[AliTRDgeometry::kNlayer];
3120 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) tseed[jLayer]=bseed[jLayer];
3121 Float_t chi2new = FitTiltedRieman(tseed, kTRUE);
3123 AliDebug(4, Form("Chi2 worsen in iter[%d].", iter));
3125 } else chi2 = chi2new;
3127 // store better tracklets
3128 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer]=tseed[jLayer];
3131 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 7 && fkReconstructor->IsDebugStreaming()){
3132 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3133 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3134 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
3135 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3136 cstreamer << "ImproveSeedQuality"
3137 << "EventNumber=" << eventNumber
3138 << "CandidateNumber=" << candidateNumber
3139 << "Iteration=" << iter
3140 << "S0.=" << &bseed[0]
3141 << "S1.=" << &bseed[1]
3142 << "S2.=" << &bseed[2]
3143 << "S3.=" << &bseed[3]
3144 << "S4.=" << &bseed[4]
3145 << "S5.=" << &bseed[5]
3146 << "FitterT.=" << tiltedRieman
3150 // we are sure that at least 2 tracklets are OK !
3154 //_________________________________________________________________________
3155 Double_t AliTRDtrackerV1::CalculateTrackLikelihood(const AliTRDseedV1 *const tracklets, Double_t *chi2){
3157 // Calculates the Track Likelihood value. This parameter serves as main quality criterion for
3158 // the track selection
3159 // The likelihood value containes:
3160 // - The chi2 values from the both fitters and the chi2 values in z-direction from a linear fit
3161 // - The Sum of the Parameter |slope_ref - slope_fit|/Sigma of the tracklets
3162 // For all Parameters an exponential dependency is used
3164 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
3165 // - Array of chi2 values:
3166 // * Non-Constrained Tilted Riemann fit
3167 // * Vertex-Constrained Tilted Riemann fit
3168 // * z-Direction from Linear fit
3169 // Output: - The calculated track likelihood
3174 Double_t chi2phi = 0, nLayers = 0;
3175 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
3176 if(!tracklets[iLayer].IsOK()) continue;
3177 chi2phi += tracklets[iLayer].GetChi2Phi();
3180 chi2phi /= Float_t (nLayers - 2.0);
3182 Double_t likeChi2Z = TMath::Exp(-chi2[2] * 0.14); // Chi2Z
3183 Double_t likeChi2TC = (fkRecoParam->IsVertexConstrained()) ?
3184 TMath::Exp(-chi2[1] * 0.677) : 1; // Constrained Tilted Riemann
3185 Double_t likeChi2TR = TMath::Exp(-chi2[0] * 0.0078); // Non-constrained Tilted Riemann
3186 Double_t likeChi2Phi= TMath::Exp(-chi2phi * 3.23);//3.23
3187 Double_t trackLikelihood = likeChi2Z * likeChi2TR * likeChi2Phi;
3189 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3190 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3191 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3192 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3193 cstreamer << "CalculateTrackLikelihood0"
3194 << "EventNumber=" << eventNumber
3195 << "CandidateNumber=" << candidateNumber
3196 << "LikeChi2Z=" << likeChi2Z
3197 << "LikeChi2TR=" << likeChi2TR
3198 << "LikeChi2TC=" << likeChi2TC
3199 << "LikeChi2Phi=" << likeChi2Phi
3200 << "TrackLikelihood=" << trackLikelihood
3204 return trackLikelihood;
3207 //____________________________________________________________________
3208 Double_t AliTRDtrackerV1::CookLikelihood(AliTRDseedV1 *cseed, Int_t planes[4])
3211 // Calculate the probability of this track candidate.
3214 // cseeds : array of candidate tracklets
3215 // planes : array of seeding planes (see seeding configuration)
3216 // chi2 : chi2 values (on the Z and Y direction) from the rieman fit of the track.
3221 // Detailed description
3223 // The track quality is estimated based on the following 4 criteria:
3224 // 1. precision of the rieman fit on the Y direction (likea)
3225 // 2. chi2 on the Y direction (likechi2y)
3226 // 3. chi2 on the Z direction (likechi2z)
3227 // 4. number of attached clusters compared to a reference value
3228 // (see AliTRDrecoParam::fkFindable) (likeN)
3230 // The distributions for each type of probabilities are given below as of
3231 // (date). They have to be checked to assure consistency of estimation.
3234 // ratio of the total number of clusters/track which are expected to be found by the tracker.
3235 Double_t chi2y = GetChi2Y(&cseed[0]);
3236 Double_t chi2z = GetChi2Z(&cseed[0]);
3238 Float_t nclusters = 0.;
3239 Double_t sumda = 0.;
3240 for(UChar_t ilayer = 0; ilayer < 4; ilayer++){
3241 Int_t jlayer = planes[ilayer];
3242 nclusters += cseed[jlayer].GetN2();
3243 sumda += TMath::Abs(cseed[jlayer].GetYfit(1) - cseed[jlayer].GetYref(1));
3247 Double_t likea = TMath::Exp(-sumda * fkRecoParam->GetPhiSlope());
3248 Double_t likechi2y = 0.0000000001;
3249 if (fkReconstructor->IsCosmic() || chi2y < fkRecoParam->GetChi2YCut()) likechi2y += TMath::Exp(-TMath::Sqrt(chi2y) * fkRecoParam->GetChi2YSlope());
3250 Double_t likechi2z = TMath::Exp(-chi2z * fkRecoParam->GetChi2ZSlope());
3251 Double_t likeN = TMath::Exp(-(fkRecoParam->GetNMeanClusters() - nclusters) / fkRecoParam->GetNSigmaClusters());
3252 Double_t like = likea * likechi2y * likechi2z * likeN;
3254 if(fkRecoParam->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3255 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3256 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3257 Int_t nTracklets = 0; Float_t meanNcls = 0;
3258 for(Int_t iseed=0; iseed < kNPlanes; iseed++){
3259 if(!cseed[iseed].IsOK()) continue;
3261 meanNcls += cseed[iseed].GetN2();
3263 if(nTracklets) meanNcls /= nTracklets;
3264 // The Debug Stream contains the seed
3265 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3266 cstreamer << "CookLikelihood"
3267 << "EventNumber=" << eventNumber
3268 << "CandidateNumber=" << candidateNumber
3269 << "tracklet0.=" << &cseed[0]
3270 << "tracklet1.=" << &cseed[1]
3271 << "tracklet2.=" << &cseed[2]
3272 << "tracklet3.=" << &cseed[3]
3273 << "tracklet4.=" << &cseed[4]
3274 << "tracklet5.=" << &cseed[5]
3275 << "sumda=" << sumda
3276 << "chi2y=" << chi2y
3277 << "chi2z=" << chi2z
3278 << "likea=" << likea
3279 << "likechi2y=" << likechi2y
3280 << "likechi2z=" << likechi2z
3281 << "nclusters=" << nclusters
3282 << "likeN=" << likeN
3284 << "meanncls=" << meanNcls
3291 //____________________________________________________________________
3292 void AliTRDtrackerV1::GetSeedingConfig(Int_t iconfig, Int_t planes[4])
3295 // Map seeding configurations to detector planes.
3298 // iconfig : configuration index
3299 // planes : member planes of this configuration. On input empty.
3302 // planes : contains the planes which are defining the configuration
3304 // Detailed description
3306 // Here is the list of seeding planes configurations together with
3307 // their topological classification:
3325 // The topologic quality is modeled as follows:
3326 // 1. The general model is define by the equation:
3327 // p(conf) = exp(-conf/2)
3328 // 2. According to the topologic classification, configurations from the same
3329 // class are assigned the agerage value over the model values.
3330 // 3. Quality values are normalized.
3332 // The topologic quality distribution as function of configuration is given below:
3334 // <img src="gif/topologicQA.gif">
3339 case 0: // 5432 TQ 0
3345 case 1: // 4321 TQ 0
3351 case 2: // 3210 TQ 0
3357 case 3: // 5321 TQ 1
3363 case 4: // 4210 TQ 1
3369 case 5: // 5431 TQ 1
3375 case 6: // 4320 TQ 1
3381 case 7: // 5430 TQ 2
3387 case 8: // 5210 TQ 2
3393 case 9: // 5421 TQ 3
3399 case 10: // 4310 TQ 3
3405 case 11: // 5410 TQ 4
3411 case 12: // 5420 TQ 5
3417 case 13: // 5320 TQ 5
3423 case 14: // 5310 TQ 5
3432 //____________________________________________________________________
3433 void AliTRDtrackerV1::GetExtrapolationConfig(Int_t iconfig, Int_t planes[2])
3436 // Returns the extrapolation planes for a seeding configuration.
3439 // iconfig : configuration index
3440 // planes : planes which are not in this configuration. On input empty.
3443 // planes : contains the planes which are not in the configuration
3445 // Detailed description
3449 case 0: // 5432 TQ 0
3453 case 1: // 4321 TQ 0
3457 case 2: // 3210 TQ 0
3461 case 3: // 5321 TQ 1
3465 case 4: // 4210 TQ 1
3469 case 5: // 5431 TQ 1
3473 case 6: // 4320 TQ 1
3477 case 7: // 5430 TQ 2
3481 case 8: // 5210 TQ 2
3485 case 9: // 5421 TQ 3
3489 case 10: // 4310 TQ 3
3493 case 11: // 5410 TQ 4
3497 case 12: // 5420 TQ 5
3501 case 13: // 5320 TQ 5
3505 case 14: // 5310 TQ 5
3512 //____________________________________________________________________
3513 AliCluster* AliTRDtrackerV1::GetCluster(Int_t idx) const
3515 if(!fClusters) return NULL;
3516 Int_t ncls = fClusters->GetEntriesFast();
3517 return idx >= 0 && idx < ncls ? (AliCluster*)fClusters->UncheckedAt(idx) : NULL;
3520 //____________________________________________________________________
3521 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(Int_t idx) const
3523 if(!fTracklets) return NULL;
3524 Int_t ntrklt = fTracklets->GetEntriesFast();
3525 return idx >= 0 && idx < ntrklt ? (AliTRDseedV1*)fTracklets->UncheckedAt(idx) : NULL;
3528 //____________________________________________________________________
3529 AliKalmanTrack* AliTRDtrackerV1::GetTrack(Int_t idx) const
3531 if(!fTracks) return NULL;
3532 Int_t ntrk = fTracks->GetEntriesFast();
3533 return idx >= 0 && idx < ntrk ? (AliKalmanTrack*)fTracks->UncheckedAt(idx) : NULL;
3538 // //_____________________________________________________________________________
3539 // Int_t AliTRDtrackerV1::Freq(Int_t n, const Int_t *inlist
3540 // , Int_t *outlist, Bool_t down)
3543 // // Sort eleements according occurancy
3544 // // The size of output array has is 2*n
3551 // Int_t *sindexS = new Int_t[n]; // Temporary array for sorting
3552 // Int_t *sindexF = new Int_t[2*n];
3553 // for (Int_t i = 0; i < n; i++) {
3557 // TMath::Sort(n,inlist,sindexS,down);
3559 // Int_t last = inlist[sindexS[0]];
3560 // Int_t val = last;
3562 // sindexF[0+n] = last;
3563 // Int_t countPos = 0;
3565 // // Find frequency
3566 // for (Int_t i = 1; i < n; i++) {
3567 // val = inlist[sindexS[i]];
3568 // if (last == val) {
3569 // sindexF[countPos]++;
3573 // sindexF[countPos+n] = val;
3574 // sindexF[countPos]++;
3578 // if (last == val) {
3582 // // Sort according frequency
3583 // TMath::Sort(countPos,sindexF,sindexS,kTRUE);
3585 // for (Int_t i = 0; i < countPos; i++) {
3586 // outlist[2*i ] = sindexF[sindexS[i]+n];
3587 // outlist[2*i+1] = sindexF[sindexS[i]];
3590 // delete [] sindexS;
3591 // delete [] sindexF;
3598 //____________________________________________________________________
3599 void AliTRDtrackerV1::ResetSeedTB()
3601 // reset buffer for seeding time bin layers. If the time bin
3602 // layers are not allocated this function allocates them
3604 for(Int_t isl=0; isl<kNSeedPlanes; isl++){
3605 if(!fSeedTB[isl]) fSeedTB[isl] = new AliTRDchamberTimeBin();
3606 else fSeedTB[isl]->Clear();
3611 //_____________________________________________________________________________
3612 Float_t AliTRDtrackerV1::GetChi2Y(const AliTRDseedV1 * const tracklets) const
3614 // Calculates normalized chi2 in y-direction
3615 // chi2 = Sum chi2 / n_tracklets
3617 Double_t chi2 = 0.; Int_t n = 0;
3618 for(Int_t ipl = kNPlanes; ipl--;){
3619 if(!tracklets[ipl].IsOK()) continue;
3620 chi2 += tracklets[ipl].GetChi2Y();
3623 return n ? chi2/n : 0.;
3626 //_____________________________________________________________________________
3627 Float_t AliTRDtrackerV1::GetChi2Z(const AliTRDseedV1 *const tracklets) const
3629 // Calculates normalized chi2 in z-direction
3630 // chi2 = Sum chi2 / n_tracklets
3632 Double_t chi2 = 0; Int_t n = 0;
3633 for(Int_t ipl = kNPlanes; ipl--;){
3634 if(!tracklets[ipl].IsOK()) continue;
3635 chi2 += tracklets[ipl].GetChi2Z();
3638 return n ? chi2/n : 0.;
3641 //____________________________________________________________________
3642 Float_t AliTRDtrackerV1::CalculateReferenceX(const AliTRDseedV1 *const tracklets){
3644 // Calculates the reference x-position for the tilted Rieman fit defined as middle
3645 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
3646 // are taken into account
3648 // Parameters: - Array of tracklets(AliTRDseedV1)
3650 // Output: - The reference x-position(Float_t)
3651 // Only kept for compatibility with the old code
3653 Int_t nDistances = 0;
3654 Float_t meanDistance = 0.;
3655 Int_t startIndex = 5;
3656 for(Int_t il =5; il > 0; il--){
3657 if(tracklets[il].IsOK() && tracklets[il -1].IsOK()){
3658 Float_t xdiff = tracklets[il].GetX0() - tracklets[il -1].GetX0();
3659 meanDistance += xdiff;
3662 if(tracklets[il].IsOK()) startIndex = il;
3664 if(tracklets[0].IsOK()) startIndex = 0;
3666 // We should normally never get here
3667 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
3668 Int_t iok = 0, idiff = 0;
3669 // This attempt is worse and should be avoided:
3670 // check for two chambers which are OK and repeat this without taking the mean value
3671 // Strategy avoids a division by 0;
3672 for(Int_t il = 5; il >= 0; il--){
3673 if(tracklets[il].IsOK()){
3674 xpos[iok] = tracklets[il].GetX0();
3678 if(iok) idiff++; // to get the right difference;
3682 meanDistance = (xpos[0] - xpos[1])/idiff;
3685 // we have do not even have 2 layers which are OK? The we do not need to fit at all
3690 meanDistance /= nDistances;
3692 return tracklets[startIndex].GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
3695 //_____________________________________________________________________________
3696 Double_t AliTRDtrackerV1::FitTiltedRiemanV1(AliTRDseedV1 *const tracklets){
3698 // Track Fitter Function using the new class implementation of
3701 AliTRDtrackFitterRieman fitter;
3702 fitter.SetRiemanFitter(GetTiltedRiemanFitter());
3704 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) fitter.SetTracklet(il, &tracklets[il]);
3705 Double_t chi2 = fitter.Eval();
3706 // Update the tracklets
3707 Double_t cov[15]; Double_t x0;
3708 memset(cov, 0, sizeof(Double_t) * 15);
3709 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++){
3710 x0 = tracklets[il].GetX0();
3711 tracklets[il].SetYref(0, fitter.GetYat(x0));
3712 tracklets[il].SetZref(0, fitter.GetZat(x0));
3713 tracklets[il].SetYref(1, fitter.GetDyDxAt(x0));
3714 tracklets[il].SetZref(1, fitter.GetDzDx());
3715 tracklets[il].SetC(fitter.GetCurvature());
3716 fitter.GetCovAt(x0, cov);
3717 tracklets[il].SetCovRef(cov);
3718 tracklets[il].SetChi2(chi2);
3723 ///////////////////////////////////////////////////////
3725 // Resources of class AliTRDLeastSquare //
3727 ///////////////////////////////////////////////////////
3729 //_____________________________________________________________________________
3730 AliTRDtrackerV1::AliTRDLeastSquare::AliTRDLeastSquare(){
3732 // Constructor of the nested class AliTRDtrackFitterLeastSquare
3734 // Fast solving linear regresion in 2D
3736 // The data members have the following meaning
3747 // fCovarianceMatrix[0] : s2a
3748 // fCovarianceMatrix[1] : s2b
3749 // fCovarianceMatrix[2] : cov(ab)
3751 memset(fParams, 0, sizeof(Double_t) * 2);
3752 memset(fSums, 0, sizeof(Double_t) * 6);
3753 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3757 //_____________________________________________________________________________
3758 void AliTRDtrackerV1::AliTRDLeastSquare::AddPoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3760 // Adding Point to the fitter
3763 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3765 const Double_t &xpt = *x;
3766 // printf("Adding point x = %f, y = %f, sigma = %f\n", xpt, y, sigmaY);
3768 fSums[1] += weight * xpt;
3769 fSums[2] += weight * y;
3770 fSums[3] += weight * xpt * y;
3771 fSums[4] += weight * xpt * xpt;
3772 fSums[5] += weight * y * y;
3775 //_____________________________________________________________________________
3776 void AliTRDtrackerV1::AliTRDLeastSquare::RemovePoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3778 // Remove Point from the sample
3781 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3783 const Double_t &xpt = *x;
3785 fSums[1] -= weight * xpt;
3786 fSums[2] -= weight * y;
3787 fSums[3] -= weight * xpt * y;
3788 fSums[4] -= weight * xpt * xpt;
3789 fSums[5] -= weight * y * y;
3792 //_____________________________________________________________________________
3793 Bool_t AliTRDtrackerV1::AliTRDLeastSquare::Eval(){
3795 // Evaluation of the fit:
3796 // Calculation of the parameters
3797 // Calculation of the covariance matrix
3800 Double_t det = fSums[0] * fSums[4] - fSums[1] *fSums[1];
3801 if(det==0) return kFALSE;
3803 // for(Int_t isum = 0; isum < 5; isum++)
3804 // printf("fSums[%d] = %f\n", isum, fSums[isum]);
3805 // printf("denominator = %f\n", denominator);
3806 fParams[0] = (fSums[2] * fSums[4] - fSums[1] * fSums[3])/det;
3807 fParams[1] = (fSums[0] * fSums[3] - fSums[1] * fSums[2])/det;
3808 // printf("fParams[0] = %f, fParams[1] = %f\n", fParams[0], fParams[1]);
3810 // Covariance matrix
3811 Double_t den = fSums[0]*fSums[4] - fSums[1]*fSums[1];
3812 fCovarianceMatrix[0] = fSums[4] / den;
3813 fCovarianceMatrix[1] = fSums[0] / den;
3814 fCovarianceMatrix[2] = -fSums[1] / den;
3815 /* fCovarianceMatrix[0] = fSums[4] / fSums[0] - fSums[1] * fSums[1] / (fSums[0] * fSums[0]);
3816 fCovarianceMatrix[1] = fSums[5] / fSums[0] - fSums[2] * fSums[2] / (fSums[0] * fSums[0]);
3817 fCovarianceMatrix[2] = fSums[3] / fSums[0] - fSums[1] * fSums[2] / (fSums[0] * fSums[0]);*/
3824 //_____________________________________________________________________________
3825 Double_t AliTRDtrackerV1::AliTRDLeastSquare::GetFunctionValue(const Double_t *const xpos) const {
3827 // Returns the Function value of the fitted function at a given x-position
3829 return fParams[0] + fParams[1] * (*xpos);
3832 //_____________________________________________________________________________
3833 void AliTRDtrackerV1::AliTRDLeastSquare::GetCovarianceMatrix(Double_t *storage) const {
3835 // Copies the values of the covariance matrix into the storage
3837 memcpy(storage, fCovarianceMatrix, sizeof(Double_t) * 3);
3840 //_____________________________________________________________________________
3841 void AliTRDtrackerV1::AliTRDLeastSquare::Reset(){
3845 memset(fParams, 0, sizeof(Double_t) * 2);
3846 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3847 memset(fSums, 0, sizeof(Double_t) * 6);
3850 ///////////////////////////////////////////////////////
3852 // Resources of class AliTRDtrackFitterRieman //
3854 ///////////////////////////////////////////////////////
3856 //_____________________________________________________________________________
3857 AliTRDtrackerV1::AliTRDtrackFitterRieman::AliTRDtrackFitterRieman():
3863 fSysClusterError(0.)
3866 // Default constructor
3868 fZfitter = new AliTRDLeastSquare;
3869 fCovarPolY = new TMatrixD(3,3);
3870 fCovarPolZ = new TMatrixD(2,2);
3871 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * 6);
3872 memset(fParameters, 0, sizeof(Double_t) * 5);
3873 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3874 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3877 //_____________________________________________________________________________
3878 AliTRDtrackerV1::AliTRDtrackFitterRieman::~AliTRDtrackFitterRieman(){
3882 if(fZfitter) delete fZfitter;
3883 if(fCovarPolY) delete fCovarPolY;
3884 if(fCovarPolZ) delete fCovarPolZ;
3887 //_____________________________________________________________________________
3888 void AliTRDtrackerV1::AliTRDtrackFitterRieman::Reset(){
3893 fTrackFitter->StoreData(kTRUE);
3894 fTrackFitter->ClearPoints();
3900 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * AliTRDgeometry::kNlayer);
3901 memset(fParameters, 0, sizeof(Double_t) * 5);
3902 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3903 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3904 for(Int_t irow = 0; irow < fCovarPolY->GetNrows(); irow++)
3905 for(Int_t icol = 0; icol < fCovarPolY->GetNcols(); icol++){
3906 (*fCovarPolY)(irow, icol) = 0.;
3907 if(irow < 2 && icol < 2)
3908 (*fCovarPolZ)(irow, icol) = 0.;
3912 //_____________________________________________________________________________
3913 void AliTRDtrackerV1::AliTRDtrackFitterRieman::SetTracklet(Int_t itr, AliTRDseedV1 *tracklet){
3915 // Add tracklet into the fitter
3917 if(itr >= AliTRDgeometry::kNlayer) return;
3918 fTracklets[itr] = tracklet;
3921 //_____________________________________________________________________________
3922 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::Eval(){
3925 // 1. Apply linear transformation and store points in the fitter
3926 // 2. Evaluate the fit
3927 // 3. Check if the result of the fit in z-direction is reasonable
3929 // 3a. Fix the parameters 3 and 4 with the results of a simple least
3931 // 3b. Redo the fit with the fixed parameters
3932 // 4. Store fit results (parameters and errors)
3937 fXref = CalculateReferenceX();
3938 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) UpdateFitters(fTracklets[il]);
3939 if(!fTrackFitter->GetNpoints()) return 1e10;
3941 fTrackFitter->Eval();
3943 fParameters[3] = fTrackFitter->GetParameter(3);
3944 fParameters[4] = fTrackFitter->GetParameter(4);
3945 if(!CheckAcceptable(fParameters[3], fParameters[4])) {
3946 fTrackFitter->FixParameter(3, fZfitter->GetFunctionValue(&fXref));
3947 fTrackFitter->FixParameter(4, fZfitter->GetFunctionParameter(1));
3948 fTrackFitter->Eval();
3949 fTrackFitter->ReleaseParameter(3);
3950 fTrackFitter->ReleaseParameter(4);
3951 fParameters[3] = fTrackFitter->GetParameter(3);
3952 fParameters[4] = fTrackFitter->GetParameter(4);
3954 // Update the Fit Parameters and the errors
3955 fParameters[0] = fTrackFitter->GetParameter(0);
3956 fParameters[1] = fTrackFitter->GetParameter(1);
3957 fParameters[2] = fTrackFitter->GetParameter(2);
3959 // Prepare Covariance estimation
3960 (*fCovarPolY)(0,0) = fSumPolY[0]; (*fCovarPolY)(1,1) = fSumPolY[2]; (*fCovarPolY)(2,2) = fSumPolY[4];
3961 (*fCovarPolY)(1,0) = (*fCovarPolY)(0,1) = fSumPolY[1];
3962 (*fCovarPolY)(2,0) = (*fCovarPolY)(0,2) = fSumPolY[2];
3963 (*fCovarPolY)(2,1) = (*fCovarPolY)(1,2) = fSumPolY[3];
3964 fCovarPolY->Invert();
3965 (*fCovarPolZ)(0,0) = fSumPolZ[0]; (*fCovarPolZ)(1,1) = fSumPolZ[2];
3966 (*fCovarPolZ)(1,0) = (*fCovarPolZ)(0,1) = fSumPolZ[1];
3967 fCovarPolZ->Invert();
3968 return fTrackFitter->GetChisquare() / fTrackFitter->GetNpoints();
3971 //_____________________________________________________________________________
3972 void AliTRDtrackerV1::AliTRDtrackFitterRieman::UpdateFitters(AliTRDseedV1 * const tracklet){
3974 // Does the transformations and updates the fitters
3975 // The following transformation is applied
3977 AliTRDcluster *cl = NULL;
3978 Double_t x, y, z, dx, t, w, we, yerr, zerr;
3980 if(!tracklet || !tracklet->IsOK()) return;
3981 Double_t tilt = tracklet->GetTilt();
3982 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
3983 if(!(cl = tracklet->GetClusters(itb))) continue;
3984 if(!cl->IsInChamber()) continue;
3985 if (!tracklet->IsUsable(itb)) continue;
3992 uvt[0] = 2. * x * t;
3994 uvt[2] = 2. * tilt * t;
3995 uvt[3] = 2. * tilt * dx * t;
3996 w = 2. * (y + tilt*z) * t;
3997 // error definition changes for the different calls
3999 we *= TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2());
4000 // Update sums for error calculation
4001 yerr = 1./(TMath::Sqrt(cl->GetSigmaY2()) + fSysClusterError);
4003 zerr = 1./cl->GetSigmaZ2();
4004 for(Int_t ipol = 0; ipol < 5; ipol++){
4005 fSumPolY[ipol] += yerr;
4008 fSumPolZ[ipol] += zerr;
4012 fTrackFitter->AddPoint(uvt, w, we);
4013 fZfitter->AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
4017 //_____________________________________________________________________________
4018 Bool_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CheckAcceptable(Double_t offset, Double_t slope){
4020 // Check whether z-results are acceptable
4021 // Definition: Distance between tracklet fit and track fit has to be
4022 // less then half a padlength
4023 // Point of comparision is at the anode wire
4025 Bool_t acceptablez = kTRUE;
4026 Double_t zref = 0.0;
4027 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
4028 if(!fTracklets[iLayer]->IsOK()) continue;
4029 zref = offset + slope * (fTracklets[iLayer]->GetX0() - fXref);
4030 if (TMath::Abs(fTracklets[iLayer]->GetZfit(0) - zref) > fTracklets[iLayer]->GetPadLength() * 0.5 + 1.0)
4031 acceptablez = kFALSE;
4036 //_____________________________________________________________________________
4037 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetYat(Double_t x) const {
4039 // Calculate y position out of the track parameters
4040 // y: R^2 = (x - x0)^2 + (y - y0)^2
4041 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
4042 // R = Sqrt() = 1/Curvature
4043 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
4046 Double_t disc = (x * fParameters[0] + fParameters[1]);
4047 disc = 1 - fParameters[0]*fParameters[2] + fParameters[1]*fParameters[1] - disc*disc;
4049 disc = TMath::Sqrt(disc);
4050 y = (1.0 - disc) / fParameters[0];
4055 //_____________________________________________________________________________
4056 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetZat(Double_t x) const {
4058 // Return z position for a given x position
4059 // Simple linear function
4061 return fParameters[3] + fParameters[4] * (x - fXref);
4064 //_____________________________________________________________________________
4065 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetDyDxAt(Double_t x) const {
4067 // Calculate dydx at a given radial position out of the track parameters
4068 // dy: R^2 = (x - x0)^2 + (y - y0)^2
4069 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
4070 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
4071 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
4072 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
4074 Double_t x0 = -fParameters[1] / fParameters[0];
4075 Double_t curvature = GetCurvature();
4077 if (-fParameters[2] * fParameters[0] + fParameters[1] * fParameters[1] + 1 > 0) {
4078 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
4079 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
4080 if (fParameters[0] < 0) yderiv *= -1.0;
4087 //_____________________________________________________________________________
4088 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCurvature() const {
4090 // Calculate track curvature
4093 Double_t curvature = 1.0 + fParameters[1]*fParameters[1] - fParameters[2]*fParameters[0];
4094 if (curvature > 0.0)
4095 curvature = fParameters[0] / TMath::Sqrt(curvature);
4099 //_____________________________________________________________________________
4100 void AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCovAt(Double_t x, Double_t *cov) const {
4102 // Error Definition according to gauss error propagation
4104 TMatrixD transform(3,3);
4105 transform(0,0) = transform(1,1) = transform(2,2) = 1;
4106 transform(0,1) = transform(1,2) = x;
4107 transform(0,2) = x*x;
4108 TMatrixD covariance(transform, TMatrixD::kMult, *fCovarPolY);
4109 covariance *= transform.T();
4110 cov[0] = covariance(0,0);
4111 TMatrixD transformZ(2,2);
4112 transformZ(0,0) = transformZ(1,1) = 1;
4113 transformZ(0,1) = x;
4114 TMatrixD covarZ(transformZ, TMatrixD::kMult, *fCovarPolZ);
4115 covarZ *= transformZ.T();
4116 cov[1] = covarZ(0,0);
4120 //____________________________________________________________________
4121 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CalculateReferenceX(){
4123 // Calculates the reference x-position for the tilted Rieman fit defined as middle
4124 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
4125 // are taken into account
4127 // Parameters: - Array of tracklets(AliTRDseedV1)
4129 // Output: - The reference x-position(Float_t)
4131 Int_t nDistances = 0;
4132 Float_t meanDistance = 0.;
4133 Int_t startIndex = 5;
4134 for(Int_t il =5; il > 0; il--){
4135 if(fTracklets[il]->IsOK() && fTracklets[il -1]->IsOK()){
4136 Float_t xdiff = fTracklets[il]->GetX0() - fTracklets[il -1]->GetX0();
4137 meanDistance += xdiff;
4140 if(fTracklets[il]->IsOK()) startIndex = il;
4142 if(fTracklets[0]->IsOK()) startIndex = 0;
4144 // We should normally never get here
4145 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
4146 Int_t iok = 0, idiff = 0;
4147 // This attempt is worse and should be avoided:
4148 // check for two chambers which are OK and repeat this without taking the mean value
4149 // Strategy avoids a division by 0;
4150 for(Int_t il = 5; il >= 0; il--){
4151 if(fTracklets[il]->IsOK()){
4152 xpos[iok] = fTracklets[il]->GetX0();
4156 if(iok) idiff++; // to get the right difference;
4160 meanDistance = (xpos[0] - xpos[1])/idiff;
4163 // we have do not even have 2 layers which are OK? The we do not need to fit at all
4168 meanDistance /= nDistances;
4170 return fTracklets[startIndex]->GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());