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)
93 // Default constructor.
96 SetReconstructor(rec); // initialize reconstructor
98 // initialize geometry
99 if(!AliGeomManager::GetGeometry()){
100 AliFatal("Could not get geometry.");
102 fGeom = new AliTRDgeometry();
103 fGeom->CreateClusterMatrixArray();
104 TGeoHMatrix *matrix = NULL;
105 Double_t loc[] = {0., 0., 0.};
106 Double_t glb[] = {0., 0., 0.};
107 for(Int_t ily=kNPlanes; ily--;){
109 while(!(matrix = fGeom->GetClusterMatrix(AliTRDgeometry::GetDetector(ily, 2, ism)))) ism++;
111 AliError(Form("Could not get transformation matrix for layer %d. Use default.", ily));
112 fR[ily] = fgkX0[ily];
115 matrix->LocalToMaster(loc, glb);
116 fR[ily] = glb[0]+ AliTRDgeometry::AnodePos()-.5*AliTRDgeometry::AmThick() - AliTRDgeometry::DrThick();
119 // initialize cluster containers
120 for (Int_t isector = 0; isector < AliTRDgeometry::kNsector; isector++) new(&fTrSec[isector]) AliTRDtrackingSector(fGeom, isector);
123 memset(fTrackQuality, 0, kMaxTracksStack*sizeof(Double_t));
124 memset(fSeedLayer, 0, kMaxTracksStack*sizeof(Int_t));
125 memset(fSeedTB, 0, kNSeedPlanes*sizeof(AliTRDchamberTimeBin*));
126 fTracksESD = new TClonesArray("AliESDtrack", 2*kMaxTracksStack);
127 fTracksESD->SetOwner();
130 //____________________________________________________________________
131 AliTRDtrackerV1::~AliTRDtrackerV1()
137 if(fgRieman) delete fgRieman; fgRieman = NULL;
138 if(fgTiltedRieman) delete fgTiltedRieman; fgTiltedRieman = NULL;
139 if(fgTiltedRiemanConstrained) delete fgTiltedRiemanConstrained; fgTiltedRiemanConstrained = NULL;
140 for(Int_t isl =0; isl<kNSeedPlanes; isl++) if(fSeedTB[isl]) delete fSeedTB[isl];
141 if(fTracksESD){ fTracksESD->Delete(); delete fTracksESD; }
142 if(fTracks) {fTracks->Delete(); delete fTracks;}
143 if(fTracklets) {fTracklets->Delete(); delete fTracklets;}
145 fClusters->Delete(); delete fClusters;
147 if(fGeom) delete fGeom;
150 //____________________________________________________________________
151 Int_t AliTRDtrackerV1::Clusters2Tracks(AliESDEvent *esd)
154 // Steering stand alone tracking for full TRD detector
157 // esd : The ESD event. On output it contains
158 // the ESD tracks found in TRD.
161 // Number of tracks found in the TRD detector.
163 // Detailed description
164 // 1. Launch individual SM trackers.
165 // See AliTRDtrackerV1::Clusters2TracksSM() for details.
168 if(!fkReconstructor->GetRecoParam() ){
169 AliError("Reconstruction configuration not initialized. Call first AliTRDReconstructor::SetRecoParam().");
173 //AliInfo("Start Track Finder ...");
175 for(int ism=0; ism<AliTRDgeometry::kNsector; ism++){
176 // for(int ism=1; ism<2; ism++){
177 //AliInfo(Form("Processing supermodule %i ...", ism));
178 ntracks += Clusters2TracksSM(ism, esd);
180 AliInfo(Form("Number of tracks: !TRDin[%d]", ntracks));
185 //_____________________________________________________________________________
186 Bool_t AliTRDtrackerV1::GetTrackPoint(Int_t index, AliTrackPoint &p) const
188 //AliInfo(Form("Asking for tracklet %d", index));
190 // reset position of the point before using it
191 p.SetXYZ(0., 0., 0.);
192 AliTRDseedV1 *tracklet = GetTracklet(index);
193 if (!tracklet) return kFALSE;
195 // get detector for this tracklet
196 Int_t det = tracklet->GetDetector();
197 Int_t sec = fGeom->GetSector(det);
198 Double_t alpha = (sec+.5)*AliTRDgeometry::GetAlpha(),
199 sinA = TMath::Sin(alpha),
200 cosA = TMath::Cos(alpha);
202 local[0] = tracklet->GetX();
203 local[1] = tracklet->GetY();
204 local[2] = tracklet->GetZ();
206 fGeom->RotateBack(det, local, global);
208 Double_t cov2D[3]; Float_t cov[6];
209 tracklet->GetCovAt(local[0], cov2D);
210 cov[0] = cov2D[0]*sinA*sinA;
211 cov[1] =-cov2D[0]*sinA*cosA;
212 cov[2] =-cov2D[1]*sinA;
213 cov[3] = cov2D[0]*cosA*cosA;
214 cov[4] = cov2D[1]*cosA;
216 // store the global position of the tracklet and its covariance matrix in the track point
217 p.SetXYZ(global[0],global[1],global[2], cov);
220 AliGeomManager::ELayerID iLayer = AliGeomManager::ELayerID(AliGeomManager::kTRD1+fGeom->GetLayer(det));
221 Int_t modId = fGeom->GetSector(det) * AliTRDgeometry::kNstack + fGeom->GetStack(det);
222 UShort_t volid = AliGeomManager::LayerToVolUID(iLayer, modId);
223 p.SetVolumeID(volid);
228 //____________________________________________________________________
229 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitter()
231 if(!fgTiltedRieman) fgTiltedRieman = new TLinearFitter(4, "hyp4");
232 return fgTiltedRieman;
235 //____________________________________________________________________
236 TLinearFitter* AliTRDtrackerV1::GetTiltedRiemanFitterConstraint()
238 if(!fgTiltedRiemanConstrained) fgTiltedRiemanConstrained = new TLinearFitter(2, "hyp2");
239 return fgTiltedRiemanConstrained;
242 //____________________________________________________________________
243 AliRieman* AliTRDtrackerV1::GetRiemanFitter()
245 if(!fgRieman) fgRieman = new AliRieman(AliTRDseedV1::kNtb * AliTRDgeometry::kNlayer);
249 //_____________________________________________________________________________
250 Int_t AliTRDtrackerV1::PropagateBack(AliESDEvent *event)
252 // Propagation of ESD tracks from TPC to TOF detectors and building of the TRD track. For building
253 // a TRD track an ESD track is used as seed. The informations obtained on the TRD track (measured points,
254 // covariance, PID, etc.) are than used to update the corresponding ESD track.
255 // Each track seed is first propagated to the geometrical limit of the TRD detector.
256 // Its prolongation is searched in the TRD and if corresponding clusters are found tracklets are
257 // constructed out of them (see AliTRDseedV1::AttachClusters()) and the track is updated.
258 // Otherwise the ESD track is left unchanged.
260 // The following steps are performed:
261 // 1. Selection of tracks based on the variance in the y-z plane.
262 // 2. Propagation to the geometrical limit of the TRD volume. If track propagation fails the AliESDtrack::kTRDStop is set.
263 // 3. Prolongation inside the fiducial volume (see AliTRDtrackerV1::FollowBackProlongation()) and marking
264 // the following status bits:
265 // - AliESDtrack::kTRDin - if the tracks enters the TRD fiducial volume
266 // - AliESDtrack::kTRDStop - if the tracks fails propagation
267 // - AliESDtrack::kTRDbackup - if the tracks fulfills chi2 conditions and qualify for refitting
268 // 4. Writting to friends, PID, MC label, quality etc. Setting status bit AliESDtrack::kTRDout.
269 // 5. Propagation to TOF. If track propagation fails the AliESDtrack::kTRDStop is set.
272 if(!fClusters || !fClusters->GetEntriesFast()){
273 AliInfo("No TRD clusters");
276 AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance(); // Calibration monitor
277 if (!calibra) AliInfo("Could not get Calibra instance");
278 if (!fgNTimeBins) fgNTimeBins = fkReconstructor->GetNTimeBins();
281 Int_t nFound = 0, // number of tracks found
282 nSeeds = 0, // total number of ESD seeds
283 nTRDseeds= 0, // number of seeds in the TRD acceptance
284 nTPCseeds= 0; // number of TPC seeds
285 Float_t foundMin = 20.0;
287 Float_t *quality = NULL;
289 nSeeds = event->GetNumberOfTracks();
290 // Sort tracks according to quality
291 // (covariance in the yz plane)
293 quality = new Float_t[nSeeds];
294 index = new Int_t[nSeeds];
295 for (Int_t iSeed = nSeeds; iSeed--;) {
296 AliESDtrack *seed = event->GetTrack(iSeed);
297 Double_t covariance[15];
298 seed->GetExternalCovariance(covariance);
299 quality[iSeed] = covariance[0] + covariance[2];
301 TMath::Sort(nSeeds, quality, index,kFALSE);
304 // Propagate all seeds
307 for (Int_t iSeed = 0; iSeed < nSeeds; iSeed++) {
309 // Get the seeds in sorted sequence
310 AliESDtrack *seed = event->GetTrack(index[iSeed]);
311 Float_t p4 = seed->GetC(seed->GetBz());
313 // Check the seed status
314 ULong_t status = seed->GetStatus();
315 if ((status & AliESDtrack::kTPCout) == 0) continue;
316 if ((status & AliESDtrack::kTRDout) != 0) continue;
318 // Propagate to the entrance in the TRD mother volume
319 new(&track) AliTRDtrackV1(*seed);
320 if(AliTRDgeometry::GetXtrdBeg() > (fgkMaxStep + track.GetX()) && !PropagateToX(track, AliTRDgeometry::GetXtrdBeg(), fgkMaxStep)){
321 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
324 if(!AdjustSector(&track)){
325 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
328 if(TMath::Abs(track.GetSnp()) > fgkMaxSnp) {
329 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
335 // store track status at TRD entrance
336 seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
338 // prepare track and do propagation in the TRD
339 track.SetReconstructor(fkReconstructor);
340 track.SetKink(Bool_t(seed->GetKinkIndex(0)));
341 expectedClr = FollowBackProlongation(track);
342 // check if track entered the TRD fiducial volume
343 if(track.GetTrackLow()){
344 seed->UpdateTrackParams(&track, AliESDtrack::kTRDin);
347 // check if track was stopped in the TRD
349 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
355 // computes PID for track
357 // update calibration references using this track
358 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(&track);
359 // save calibration object
360 if (fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
361 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(track);
362 calibTrack->SetOwner();
363 seed->AddCalibObject(calibTrack);
366 seed->UpdateTrackParams(&track, AliESDtrack::kTRDout);
367 track.UpdateESDtrack(seed);
370 if ((TMath::Abs(track.GetC(track.GetBz()) - p4) / TMath::Abs(p4) < 0.2) ||(track.Pt() > 0.8)) {
372 // Make backup for back propagation
373 Int_t foundClr = track.GetNumberOfClusters();
374 if (foundClr >= foundMin) {
375 track.CookLabel(1. - fgkLabelFraction);
376 //if(track.GetBackupTrack()) UseClusters(track.GetBackupTrack());
378 // Sign only gold tracks
379 if (track.GetChi2() / track.GetNumberOfClusters() < 4) {
380 //if ((seed->GetKinkIndex(0) == 0) && (track.Pt() < 1.5)) UseClusters(&track);
382 Bool_t isGold = kFALSE;
385 if (track.GetChi2() / track.GetNumberOfClusters() < 5) {
386 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
392 if ((!isGold) && (track.GetNCross() == 0) && (track.GetChi2() / track.GetNumberOfClusters() < 7)) {
393 //seed->UpdateTrackParams(track, AliESDtrack::kTRDbackup);
394 if (track.GetBackupTrack()) seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
399 if ((!isGold) && (track.GetBackupTrack())) {
400 if ((track.GetBackupTrack()->GetNumberOfClusters() > foundMin) && ((track.GetBackupTrack()->GetChi2()/(track.GetBackupTrack()->GetNumberOfClusters()+1)) < 7)) {
401 seed->UpdateTrackParams(track.GetBackupTrack(),AliESDtrack::kTRDbackup);
408 // Propagation to the TOF
409 if(!(seed->GetStatus()&AliESDtrack::kTRDStop)) {
410 Int_t sm = track.GetSector();
411 // default value in case we have problems with the geometry.
412 Double_t xtof = 371.;
413 //Calculate radial position of the beginning of the TOF
414 //mother volume. In order to avoid mixing of the TRD
415 //and TOF modules some hard values are needed. This are:
416 //1. The path to the TOF module.
417 //2. The width of the TOF (29.05 cm)
418 //(with the help of Annalisa de Caro Mar-17-2009)
420 gGeoManager->cd(Form("/ALIC_1/B077_1/BSEGMO%d_1/BTOF%d_1", sm, sm));
421 TGeoHMatrix *m = NULL;
422 Double_t loc[]={0., 0., -.5*29.05}, glob[3];
424 if((m=gGeoManager->GetCurrentMatrix())){
425 m->LocalToMaster(loc, glob);
426 xtof = TMath::Sqrt(glob[0]*glob[0]+glob[1]*glob[1]);
429 if(xtof > (fgkMaxStep + track.GetX()) && !PropagateToX(track, xtof, fgkMaxStep)){
430 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
433 if(!AdjustSector(&track)){
434 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
437 if(TMath::Abs(track.GetSnp()) > fgkMaxSnp){
438 seed->UpdateTrackParams(&track, AliESDtrack::kTRDStop);
441 //seed->UpdateTrackParams(&track, AliESDtrack::kTRDout);
442 // TODO obsolete - delete
443 seed->SetTRDQuality(track.StatusForTOF());
445 seed->SetTRDBudget(track.GetBudget(0));
447 if(index) delete [] index;
448 if(quality) delete [] quality;
450 AliInfo(Form("Number of seeds: TPCout[%d] TRDin[%d]", nTPCseeds, nTRDseeds));
451 AliInfo(Form("Number of tracks: TRDout[%d]", nFound));
453 // run stand alone tracking
454 if (fkReconstructor->IsSeeding()) Clusters2Tracks(event);
460 //____________________________________________________________________
461 Int_t AliTRDtrackerV1::RefitInward(AliESDEvent *event)
464 // Refits tracks within the TRD. The ESD event is expected to contain seeds
465 // at the outer part of the TRD.
466 // The tracks are propagated to the innermost time bin
467 // of the TRD and the ESD event is updated
468 // Origin: Thomas KUHR (Thomas.Kuhr@cern.ch)
471 Int_t nseed = 0; // contor for loaded seeds
472 Int_t found = 0; // contor for updated TRD tracks
475 if(!fClusters || !fClusters->GetEntriesFast()){
476 AliInfo("No TRD clusters");
480 for (Int_t itrack = 0; itrack < event->GetNumberOfTracks(); itrack++) {
481 AliESDtrack *seed = event->GetTrack(itrack);
482 ULong_t status = seed->GetStatus();
484 new(&track) AliTRDtrackV1(*seed);
485 if (track.GetX() < 270.0) {
486 seed->UpdateTrackParams(&track, AliESDtrack::kTRDbackup);
490 // reject tracks which failed propagation in the TRD or
491 // are produced by the TRD stand alone tracker
492 if(!(status & AliESDtrack::kTRDout)) continue;
493 if(!(status & AliESDtrack::kTRDin)) continue;
496 track.ResetCovariance(50.0);
498 // do the propagation and processing
499 Bool_t kUPDATE = kFALSE;
500 Double_t xTPC = 250.0;
501 if(FollowProlongation(track)){
503 if (PropagateToX(track, xTPC, fgkMaxStep)) { // -with update
504 seed->UpdateTrackParams(&track, AliESDtrack::kTRDrefit);
509 // Update the friend track
510 if (fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
511 TObject *o = NULL; Int_t ic = 0;
512 AliTRDtrackV1 *calibTrack = NULL;
513 while((o = seed->GetCalibObject(ic++))){
514 if(!(calibTrack = dynamic_cast<AliTRDtrackV1*>(o))) continue;
515 calibTrack->SetTrackHigh(track.GetTrackHigh());
520 // Prolongate to TPC without update
522 AliTRDtrackV1 tt(*seed);
523 if (PropagateToX(tt, xTPC, fgkMaxStep)) seed->UpdateTrackParams(&tt, AliESDtrack::kTRDbackup);
526 AliInfo(Form("Number of seeds: TRDout[%d]", nseed));
527 AliInfo(Form("Number of tracks: TRDrefit[%d]", found));
532 //____________________________________________________________________
533 Int_t AliTRDtrackerV1::FollowProlongation(AliTRDtrackV1 &t)
535 // Extrapolates the TRD track in the TPC direction.
538 // t : the TRD track which has to be extrapolated
541 // number of clusters attached to the track
543 // Detailed description
545 // Starting from current radial position of track <t> this function
546 // extrapolates the track through the 6 TRD layers. The following steps
547 // are being performed for each plane:
549 // a. get plane limits in the local x direction
550 // b. check crossing sectors
551 // c. check track inclination
552 // 2. search tracklet in the tracker list (see GetTracklet() for details)
553 // 3. evaluate material budget using the geo manager
554 // 4. propagate and update track using the tracklet information.
559 Bool_t kStoreIn = kTRUE;
560 Int_t nClustersExpected = 0;
561 for (Int_t iplane = kNPlanes; iplane--;) {
563 AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
564 AliDebug(2, Form("Tracklet[%p] ly[%d] idx[%d]", (void*)tracklet, iplane, index));
565 if(!tracklet) continue;
566 if(!tracklet->IsOK()){
567 AliDebug(1, Form("Tracklet Det[%d] !OK", tracklet->GetDetector()));
570 Double_t x = tracklet->GetX();//GetX0();
571 // reject tracklets which are not considered for inward refit
572 if(x > t.GetX()+fgkMaxStep) continue;
574 // append tracklet to track
575 t.SetTracklet(tracklet, index);
577 if (x < (t.GetX()-fgkMaxStep) && !PropagateToX(t, x+fgkMaxStep, fgkMaxStep)) break;
578 if (!AdjustSector(&t)) break;
580 // Start global position
584 // End global position
585 Double_t alpha = t.GetAlpha(), y, z;
586 if (!t.GetProlongation(x,y,z)) break;
588 xyz1[0] = x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
589 xyz1[1] = x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
592 Double_t length = TMath::Sqrt(
593 (xyz0[0]-xyz1[0])*(xyz0[0]-xyz1[0]) +
594 (xyz0[1]-xyz1[1])*(xyz0[1]-xyz1[1]) +
595 (xyz0[2]-xyz1[2])*(xyz0[2]-xyz1[2])
598 // Get material budget
600 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param)<=0.) break;
601 Double_t xrho= param[0]*param[4];
602 Double_t xx0 = param[1]; // Get mean propagation parameters
604 // Propagate and update
605 t.PropagateTo(x, xx0, xrho);
606 if (!AdjustSector(&t)) break;
613 Double_t cov[3]; tracklet->GetCovAt(x, cov);
614 Double_t p[2] = { tracklet->GetY(), tracklet->GetZ()};
615 Double_t chi2 = ((AliExternalTrackParam)t).GetPredictedChi2(p, cov);
616 if (chi2 < 1e+10 && t.Update(p, cov, chi2)){
617 nClustersExpected += tracklet->GetN();
621 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 1){
623 for(int iplane=0; iplane<AliTRDgeometry::kNlayer; iplane++){
624 AliTRDseedV1 *tracklet = GetTracklet(&t, iplane, index);
625 if(!tracklet) continue;
626 t.SetTracklet(tracklet, index);
629 if(fkReconstructor->IsDebugStreaming()){
630 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
631 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
632 AliTRDtrackV1 track(t);
634 cstreamer << "FollowProlongation"
635 << "EventNumber=" << eventNumber
636 << "ncl=" << nClustersExpected
637 << "track.=" << &track
641 return nClustersExpected;
645 //_____________________________________________________________________________
646 Int_t AliTRDtrackerV1::FollowBackProlongation(AliTRDtrackV1 &t)
648 // Extrapolates/Build the TRD track in the TOF direction.
651 // t : the TRD track which has to be extrapolated
654 // number of clusters attached to the track
656 // Starting from current radial position of track <t> this function
657 // extrapolates the track through the 6 TRD layers. The following steps
658 // are being performed for each plane:
659 // 1. Propagate track to the entrance of the next chamber:
660 // - get chamber limits in the radial direction
661 // - check crossing sectors
662 // - check track inclination
663 // - check track prolongation against boundary conditions (see exclusion boundaries on AliTRDgeometry::IsOnBoundary())
664 // 2. Build tracklet (see AliTRDseed::AttachClusters() for details) for this layer if needed. If only
665 // Kalman filter is needed and tracklets are already linked to the track this step is skipped.
666 // 3. Fit tracklet using the information from the Kalman filter.
667 // 4. Propagate and update track at reference radial position of the tracklet.
668 // 5. Register tracklet with the tracker and track; update pulls monitoring.
671 // 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:
672 // - AliTRDtrackV1::kProlongation : track prolongation failed
673 // - AliTRDtrackV1::kPropagation : track prolongation failed
674 // - AliTRDtrackV1::kAdjustSector : failed during sector crossing
675 // - AliTRDtrackV1::kSnp : too large bending
676 // - AliTRDtrackV1::kTrackletInit : fail to initialize tracklet
677 // - AliTRDtrackV1::kUpdate : fail to attach clusters or fit the tracklet
678 // - AliTRDtrackV1::kUnknown : anything which is not covered before
679 // 2. By default the status of the track before first TRD update is saved.
684 // Alexandru Bercuci <A.Bercuci@gsi.de>
688 Double_t driftLength = .5*AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick();
689 AliTRDtrackingChamber *chamber = NULL;
691 Int_t debugLevel = fkReconstructor->IsDebugStreaming() ? fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) : 0;
692 TTreeSRedirector *cstreamer = fkReconstructor->IsDebugStreaming() ? fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker) : 0x0;
694 AliTRDseedV1 tracklet, *ptrTracklet = NULL;
695 // in case of stand alone tracking we store all the pointers to the tracklets in a temporary array
696 AliTRDseedV1 *tracklets[kNPlanes];
697 memset(tracklets, 0, sizeof(AliTRDseedV1 *) * kNPlanes);
698 for(Int_t ip = 0; ip < kNPlanes; ip++){
699 tracklets[ip] = t.GetTracklet(ip);
702 Bool_t kStoreIn(kTRUE), //
703 kPropagateIn(kTRUE),//
704 kUseTRD(fkReconstructor->GetRecoParam()->IsOverPtThreshold(t.Pt()));// use TRD measurment to update Kalman
706 // Loop through the TRD layers
707 TGeoHMatrix *matrix = NULL;
709 for (Int_t ily=0, sm=-1, stk=-1, det=-1; ily < AliTRDgeometry::kNlayer; ily++) {
710 AliDebug(2, Form("Propagate to x[%d] = %7.2f", ily, fR[ily]));
712 // rough estimate of the entry point
713 if (!t.GetProlongation(fR[ily], y, z)){
715 t.SetStatus(AliTRDtrackV1::kProlongation);
716 AliDebug(4, Form("Failed Rough Prolongation to ly[%d] x[%7.2f] y[%7.2f] z[%7.2f]", ily, fR[ily], y, z));
720 // find sector / stack / detector
722 // TODO cross check with y value !
723 stk = fGeom->GetStack(z, ily);
724 det = stk>=0 ? AliTRDgeometry::GetDetector(ily, stk, sm) : -1;
725 matrix = det>=0 ? fGeom->GetClusterMatrix(det) : NULL;
726 AliDebug(3, Form("Propagate to det[%3d]", det));
728 // check if supermodule/chamber is installed
729 if( !fGeom->GetSMstatus(sm) ||
731 fGeom->IsHole(ily, stk, sm) ||
733 AliDebug(4, Form("Missing Geometry ly[%d]. Guess radial position", ily));
734 // propagate to the default radial position
735 if(fR[ily] > (fgkMaxStep + t.GetX()) && !PropagateToX(t, fR[ily], fgkMaxStep)){
737 t.SetStatus(AliTRDtrackV1::kPropagation);
738 AliDebug(4, "Failed Propagation [Missing Geometry]");
741 if(!AdjustSector(&t)){
743 t.SetStatus(AliTRDtrackV1::kAdjustSector);
744 AliDebug(4, "Failed Adjust Sector [Missing Geometry]");
747 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp){
749 t.SetStatus(AliTRDtrackV1::kSnp);
750 AliDebug(4, "Failed Max Snp [Missing Geometry]");
753 t.SetStatus(AliTRDtrackV1::kGeometry, ily);
757 // retrieve rotation matrix for the current chamber
758 Double_t loc[] = {AliTRDgeometry::AnodePos()- driftLength, 0., 0.};
759 Double_t glb[] = {0., 0., 0.};
760 matrix->LocalToMaster(loc, glb);
762 // Propagate to the radial distance of the current layer
763 x = glb[0] - fgkMaxStep;
764 if(x > (fgkMaxStep + t.GetX()) && !PropagateToX(t, x, fgkMaxStep)){
766 t.SetStatus(AliTRDtrackV1::kPropagation);
767 AliDebug(4, Form("Failed Initial Propagation to x[%7.2f]", x));
770 if(!AdjustSector(&t)){
772 t.SetStatus(AliTRDtrackV1::kAdjustSector);
773 AliDebug(4, "Failed Adjust Sector Start");
776 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp) {
778 t.SetStatus(AliTRDtrackV1::kSnp);
779 AliDebug(4, Form("Failed Max Snp[%f] MaxSnp[%f]", t.GetSnp(), fgkMaxSnp));
782 Bool_t doRecalculate = kFALSE;
783 if(sm != t.GetSector()){
785 doRecalculate = kTRUE;
787 if(stk != fGeom->GetStack(z, ily)){
788 stk = fGeom->GetStack(z, ily);
789 doRecalculate = kTRUE;
792 det = AliTRDgeometry::GetDetector(ily, stk, sm);
793 if(!(matrix = fGeom->GetClusterMatrix(det))){
794 t.SetStatus(AliTRDtrackV1::kGeometry, ily);
795 AliDebug(4, Form("Failed Geometry Matrix ly[%d]", ily));
798 matrix->LocalToMaster(loc, glb);
799 x = glb[0] - fgkMaxStep;
802 // check if track is well inside fiducial volume
803 if (!t.GetProlongation(x+fgkMaxStep, y, z)) {
805 t.SetStatus(AliTRDtrackV1::kProlongation);
806 AliDebug(4, Form("Failed Prolongation to x[%7.2f] y[%7.2f] z[%7.2f]", x+fgkMaxStep, y, z));
809 if(fGeom->IsOnBoundary(det, y, z, .5)){
810 t.SetStatus(AliTRDtrackV1::kBoundary, ily);
811 AliDebug(4, "Failed Track on Boundary");
814 // mark track as entering the FIDUCIAL volume of TRD
820 ptrTracklet = tracklets[ily];
821 if(!ptrTracklet){ // BUILD TRACKLET
822 AliDebug(3, Form("Building tracklet det[%d]", det));
823 // check data in supermodule
824 if(!fTrSec[sm].GetNChambers()){
825 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
826 AliDebug(4, "Failed NoClusters");
829 if(fTrSec[sm].GetX(ily) < 1.){
830 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
831 AliDebug(4, "Failed NoX");
835 // check data in chamber
836 if(!(chamber = fTrSec[sm].GetChamber(stk, ily))){
837 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
838 AliDebug(4, "Failed No Detector");
841 if(chamber->GetNClusters() < fgNTimeBins*fkReconstructor->GetRecoParam() ->GetFindableClusters()){
842 t.SetStatus(AliTRDtrackV1::kNoClusters, ily);
843 AliDebug(4, "Failed Not Enough Clusters in Detector");
847 ptrTracklet = new(&tracklet) AliTRDseedV1(det);
848 ptrTracklet->SetReconstructor(fkReconstructor);
849 ptrTracklet->SetKink(t.IsKink());
850 ptrTracklet->SetPadPlane(fGeom->GetPadPlane(ily, stk));
851 ptrTracklet->SetX0(glb[0]+driftLength);
852 if(!tracklet.Init(&t)){
854 t.SetStatus(AliTRDtrackV1::kTrackletInit);
855 AliDebug(4, "Failed Tracklet Init");
858 if(!tracklet.AttachClusters(chamber, kTRUE)){
859 t.SetStatus(AliTRDtrackV1::kNoAttach, ily);
861 AliTRDseedV1 trackletCp(*ptrTracklet);
862 UChar_t status(t.GetStatusTRD(ily));
863 (*cstreamer) << "FollowBackProlongation2"
864 <<"status=" << status
865 <<"tracklet.=" << &trackletCp
868 AliDebug(4, "Failed Attach Clusters");
871 AliDebug(3, Form("Number of Clusters in Tracklet: %d", tracklet.GetN()));
872 if(tracklet.GetN() < fgNTimeBins*fkReconstructor->GetRecoParam() ->GetFindableClusters()){
873 t.SetStatus(AliTRDtrackV1::kNoClustersTracklet, ily);
875 AliTRDseedV1 trackletCp(*ptrTracklet);
876 UChar_t status(t.GetStatusTRD(ily));
877 (*cstreamer) << "FollowBackProlongation2"
878 <<"status=" << status
879 <<"tracklet.=" << &trackletCp
882 AliDebug(4, "Failed N Clusters Attached");
885 ptrTracklet->UpdateUsed();
886 } else AliDebug(2, Form("Use external tracklet ly[%d]", ily));
887 // propagate track to the radial position of the tracklet
888 ptrTracklet->UseClusters(); // TODO ? do we need this here ?
889 // fit tracklet no tilt correction
890 if(!ptrTracklet->Fit(kFALSE)){
891 t.SetStatus(AliTRDtrackV1::kNoFit, ily);
892 AliDebug(4, "Failed Tracklet Fit");
895 x = ptrTracklet->GetX(); //GetX0();
896 if(x > (fgkMaxStep + t.GetX()) && !PropagateToX(t, x, fgkMaxStep)) {
898 t.SetStatus(AliTRDtrackV1::kPropagation);
899 AliDebug(4, Form("Failed Propagation to Tracklet x[%7.2f]", x));
902 if(!AdjustSector(&t)) {
904 t.SetStatus(AliTRDtrackV1::kAdjustSector);
905 AliDebug(4, "Failed Adjust Sector");
908 if(TMath::Abs(t.GetSnp()) > fgkMaxSnp) {
910 t.SetStatus(AliTRDtrackV1::kSnp);
911 AliDebug(4, Form("Failed Max Snp[%f] MaxSnp[%f]", t.GetSnp(), fgkMaxSnp));
916 kPropagateIn = kFALSE;
918 Double_t cov[3]; ptrTracklet->GetCovAt(x, cov);
919 Double_t p[2] = { ptrTracklet->GetY(), ptrTracklet->GetZ()};
920 Double_t chi2 = ((AliExternalTrackParam)t).GetPredictedChi2(p, cov);
921 // update Kalman with the TRD measurement
922 if(chi2>1e+10){ // TODO
923 t.SetStatus(AliTRDtrackV1::kChi2, ily);
925 UChar_t status(t.GetStatusTRD());
926 AliTRDseedV1 trackletCp(*ptrTracklet);
927 AliTRDtrackV1 trackCp(t);
929 (*cstreamer) << "FollowBackProlongation1"
930 << "status=" << status
931 << "tracklet.=" << &trackletCp
932 << "track.=" << &trackCp
935 AliDebug(4, Form("Failed Chi2[%f]", chi2));
938 if(!t.Update(p, cov, chi2, kUseTRD)) {
940 t.SetStatus(AliTRDtrackV1::kUpdate);
942 UChar_t status(t.GetStatusTRD());
943 AliTRDseedV1 trackletCp(*ptrTracklet);
944 AliTRDtrackV1 trackCp(t);
946 (*cstreamer) << "FollowBackProlongation1"
947 << "status=" << status
948 << "tracklet.=" << &trackletCp
949 << "track.=" << &trackCp
952 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]));
956 AliTracker::FillResiduals(&t, p, cov, ptrTracklet->GetVolumeId());
959 // load tracklet to the tracker
960 ptrTracklet->Update(&t);
961 ptrTracklet = SetTracklet(ptrTracklet);
962 Int_t index(fTracklets->GetEntriesFast()-1);
963 t.SetTracklet(ptrTracklet, index);
964 n += ptrTracklet->GetN();
965 AliDebug(2, Form("Setting Tracklet[%d] @ Idx[%d]", ily, index));
967 // Reset material budget if 2 consecutive gold
968 // if(ilayer>0 && t.GetTracklet(ilayer-1) && ptrTracklet->GetN() + t.GetTracklet(ilayer-1)->GetN() > 20) t.SetBudget(2, 0.);
970 // Make backup of the track until is gold
971 // TO DO update quality check of the track.
972 // consider comparison with fTimeBinsRange
973 Float_t ratio0 = ptrTracklet->GetN() / Float_t(fgNTimeBins);
974 //Float_t ratio1 = Float_t(t.GetNumberOfClusters()+1) / Float_t(t.GetNExpected()+1);
979 //(ratio0+ratio1 > 1.5) &&
980 (t.GetNCross() == 0) &&
981 (TMath::Abs(t.GetSnp()) < 0.85) &&
982 (t.GetNumberOfClusters() > 20)){
986 //printf("clusters[%d] chi2[%f] x[%f] status[%d ", n, t.GetChi2(), t.GetX(), t.GetStatusTRD());
987 //for(int i=0; i<6; i++) printf("%d ", t.GetStatusTRD(i)); printf("]\n");
990 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
991 AliTRDtrackV1 track(t);
993 (*cstreamer) << "FollowBackProlongation0"
994 << "EventNumber=" << eventNumber
996 << "track.=" << &track
1003 //_________________________________________________________________________
1004 Float_t AliTRDtrackerV1::FitRieman(AliTRDseedV1 *tracklets, Double_t *chi2, Int_t *const planes){
1006 // Fits a Riemann-circle to the given points without tilting pad correction.
1007 // The fit is performed using an instance of the class AliRieman (equations
1008 // and transformations see documentation of this class)
1009 // Afterwards all the tracklets are Updated
1011 // Parameters: - Array of tracklets (AliTRDseedV1)
1012 // - Storage for the chi2 values (beginning with direction z)
1013 // - Seeding configuration
1014 // Output: - The curvature
1016 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1018 Int_t allplanes[] = {0, 1, 2, 3, 4, 5};
1019 Int_t *ppl = &allplanes[0];
1020 Int_t maxLayers = 6;
1025 for(Int_t il = 0; il < maxLayers; il++){
1026 if(!tracklets[ppl[il]].IsOK()) continue;
1027 fitter->AddPoint(tracklets[ppl[il]].GetX0(), tracklets[ppl[il]].GetYfit(0), tracklets[ppl[il]].GetZfit(0),1,10);
1030 // Set the reference position of the fit and calculate the chi2 values
1031 memset(chi2, 0, sizeof(Double_t) * 2);
1032 for(Int_t il = 0; il < maxLayers; il++){
1033 // Reference positions
1034 tracklets[ppl[il]].Init(fitter);
1037 if((!tracklets[ppl[il]].IsOK()) && (!planes)) continue;
1038 chi2[0] += tracklets[ppl[il]].GetChi2Y();
1039 chi2[1] += tracklets[ppl[il]].GetChi2Z();
1041 return fitter->GetC();
1044 //_________________________________________________________________________
1045 void AliTRDtrackerV1::FitRieman(AliTRDcluster **seedcl, Double_t chi2[2])
1048 // Performs a Riemann helix fit using the seedclusters as spacepoints
1049 // Afterwards the chi2 values are calculated and the seeds are updated
1051 // Parameters: - The four seedclusters
1052 // - The tracklet array (AliTRDseedV1)
1053 // - The seeding configuration
1058 AliRieman *fitter = AliTRDtrackerV1::GetRiemanFitter();
1060 for(Int_t i = 0; i < 4; i++){
1061 fitter->AddPoint(seedcl[i]->GetX(), seedcl[i]->GetY(), seedcl[i]->GetZ(), 1., 10.);
1066 // Update the seed and calculated the chi2 value
1067 chi2[0] = 0; chi2[1] = 0;
1068 for(Int_t ipl = 0; ipl < kNSeedPlanes; ipl++){
1070 chi2[0] += (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetZ() - fitter->GetZat(seedcl[ipl]->GetX()));
1071 chi2[1] += (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX())) * (seedcl[ipl]->GetY() - fitter->GetYat(seedcl[ipl]->GetX()));
1076 //_________________________________________________________________________
1077 Float_t AliTRDtrackerV1::FitTiltedRiemanConstraint(AliTRDseedV1 *tracklets, Double_t zVertex)
1080 // Fits a helix to the clusters. Pad tilting is considered. As constraint it is
1081 // assumed that the vertex position is set to 0.
1082 // This method is very usefull for high-pt particles
1083 // Basis for the fit: (x - x0)^2 + (y - y0)^2 - R^2 = 0
1084 // x0, y0: Center of the circle
1085 // Measured y-position: ymeas = y - tan(phiT)(zc - zt)
1086 // zc: center of the pad row
1087 // Equation which has to be fitted (after transformation):
1088 // a + b * u + e * v + 2*(ymeas + tan(phiT)(z - zVertex))*t = 0
1090 // t = 1/(x^2 + y^2)
1092 // v = 2 * x * tan(phiT) * t
1093 // Parameters in the equation:
1094 // a = -1/y0, b = x0/y0, e = dz/dx
1096 // The Curvature is calculated by the following equation:
1097 // - curv = a/Sqrt(b^2 + 1) = 1/R
1098 // Parameters: - the 6 tracklets
1099 // - the Vertex constraint
1100 // Output: - the Chi2 value of the track
1105 TLinearFitter *fitter = GetTiltedRiemanFitterConstraint();
1106 fitter->StoreData(kTRUE);
1107 fitter->ClearPoints();
1108 AliTRDcluster *cl = NULL;
1110 Float_t x, y, z, w, t, error, tilt;
1113 for(Int_t ilr = 0; ilr < AliTRDgeometry::kNlayer; ilr++){
1114 if(!tracklets[ilr].IsOK()) continue;
1115 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1116 if(!tracklets[ilr].IsUsable(itb)) continue;
1117 cl = tracklets[ilr].GetClusters(itb);
1118 if(!cl->IsInChamber()) continue;
1122 tilt = tracklets[ilr].GetTilt();
1124 t = 1./(x * x + y * y);
1125 uvt[0] = 2. * x * t;
1126 uvt[1] = 2. * x * t * tilt ;
1127 w = 2. * (y + tilt * (z - zVertex)) * t;
1128 error = 2. * TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) * t;
1129 fitter->AddPoint(uvt, w, error);
1135 // Calculate curvature
1136 Double_t a = fitter->GetParameter(0);
1137 Double_t b = fitter->GetParameter(1);
1138 Double_t curvature = a/TMath::Sqrt(b*b + 1);
1140 Float_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1141 for(Int_t ip = 0; ip < AliTRDtrackerV1::kNPlanes; ip++)
1142 tracklets[ip].SetC(curvature);
1144 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker()) >= 5){
1145 //Linear Model on z-direction
1146 Double_t xref = CalculateReferenceX(tracklets); // Relative to the middle of the stack
1147 Double_t slope = fitter->GetParameter(2);
1148 Double_t zref = slope * xref;
1149 Float_t chi2Z = CalculateChi2Z(tracklets, zref, slope, xref);
1150 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1151 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1152 TTreeSRedirector &treeStreamer = *fkReconstructor->GetDebugStream(AliTRDReconstructor::kTracker);
1153 treeStreamer << "FitTiltedRiemanConstraint"
1154 << "EventNumber=" << eventNumber
1155 << "CandidateNumber=" << candidateNumber
1156 << "Curvature=" << curvature
1157 << "Chi2Track=" << chi2track
1158 << "Chi2Z=" << chi2Z
1165 //_________________________________________________________________________
1166 Float_t AliTRDtrackerV1::FitTiltedRieman(AliTRDseedV1 *tracklets, Bool_t sigError)
1169 // Performs a Riemann fit taking tilting pad correction into account
1170 // The equation of a Riemann circle, where the y position is substituted by the
1171 // measured y-position taking pad tilting into account, has to be transformed
1172 // into a 4-dimensional hyperplane equation
1173 // Riemann circle: (x-x0)^2 + (y-y0)^2 -R^2 = 0
1174 // Measured y-Position: ymeas = y - tan(phiT)(zc - zt)
1175 // zc: center of the pad row
1176 // zt: z-position of the track
1177 // The z-position of the track is assumed to be linear dependent on the x-position
1178 // Transformed equation: a + b * u + c * t + d * v + e * w - 2 * (ymeas + tan(phiT) * zc) * t = 0
1179 // Transformation: u = 2 * x * t
1180 // v = 2 * tan(phiT) * t
1181 // w = 2 * tan(phiT) * (x - xref) * t
1182 // t = 1 / (x^2 + ymeas^2)
1183 // Parameters: a = -1/y0
1185 // c = (R^2 -x0^2 - y0^2)/y0
1188 // If the offset respectively the slope in z-position is impossible, the parameters are fixed using
1189 // results from the simple riemann fit. Afterwards the fit is redone.
1190 // The curvature is calculated according to the formula:
1191 // curv = a/(1 + b^2 + c*a) = 1/R
1193 // Paramters: - Array of tracklets (connected to the track candidate)
1194 // - Flag selecting the error definition
1195 // Output: - Chi2 values of the track (in Parameter list)
1197 TLinearFitter *fitter = GetTiltedRiemanFitter();
1198 fitter->StoreData(kTRUE);
1199 fitter->ClearPoints();
1200 AliTRDLeastSquare zfitter;
1201 AliTRDcluster *cl = NULL;
1203 Double_t xref = CalculateReferenceX(tracklets);
1204 Double_t x, y, z, t, tilt, dx, w, we, erry, errz;
1205 Double_t uvt[4], sumPolY[5], sumPolZ[3];
1206 memset(sumPolY, 0, sizeof(Double_t) * 5);
1207 memset(sumPolZ, 0, sizeof(Double_t) * 3);
1209 // Containers for Least-square fitter
1210 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1211 if(!tracklets[ipl].IsOK()) continue;
1212 tilt = tracklets[ipl].GetTilt();
1213 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1214 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1215 if(!cl->IsInChamber()) continue;
1216 if (!tracklets[ipl].IsUsable(itb)) continue;
1223 uvt[0] = 2. * x * t;
1225 uvt[2] = 2. * tilt * t;
1226 uvt[3] = 2. * tilt * dx * t;
1227 w = 2. * (y + tilt*z) * t;
1228 // error definition changes for the different calls
1230 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2()) : 0.2;
1231 fitter->AddPoint(uvt, w, we);
1232 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1233 // adding points for covariance matrix estimation
1234 erry = 1./(TMath::Sqrt(cl->GetSigmaY2()) + 0.1); // 0.1 is a systematic error (due to misalignment and miscalibration)
1236 errz = 1./cl->GetSigmaZ2();
1237 for(Int_t ipol = 0; ipol < 5; ipol++){
1238 sumPolY[ipol] += erry;
1241 sumPolZ[ipol] += errz;
1251 Double_t offset = fitter->GetParameter(3);
1252 Double_t slope = fitter->GetParameter(4);
1254 // Linear fitter - not possible to make boundaries
1255 // Do not accept non possible z and dzdx combinations
1256 Bool_t acceptablez = kTRUE;
1257 Double_t zref = 0.0;
1258 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1259 if(!tracklets[iLayer].IsOK()) continue;
1260 zref = offset + slope * (tracklets[iLayer].GetX0() - xref);
1261 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1262 acceptablez = kFALSE;
1265 Double_t dzmf = zfitter.GetFunctionParameter(1);
1266 Double_t zmf = zfitter.GetFunctionValue(&xref);
1267 fgTiltedRieman->FixParameter(3, zmf);
1268 fgTiltedRieman->FixParameter(4, dzmf);
1270 fitter->ReleaseParameter(3);
1271 fitter->ReleaseParameter(4);
1272 offset = fitter->GetParameter(3);
1273 slope = fitter->GetParameter(4);
1276 // Calculate Curvarture
1277 Double_t a = fitter->GetParameter(0);
1278 Double_t b = fitter->GetParameter(1);
1279 Double_t c = fitter->GetParameter(2);
1280 Double_t curvature = 1.0 + b*b - c*a;
1281 if (curvature > 0.0)
1282 curvature = a / TMath::Sqrt(curvature);
1284 Double_t chi2track = fitter->GetChisquare()/Double_t(nPoints);
1286 // Prepare error calculation
1287 TMatrixD covarPolY(3,3);
1288 covarPolY(0,0) = sumPolY[0]; covarPolY(1,1) = sumPolY[2]; covarPolY(2,2) = sumPolY[4];
1289 covarPolY(0,1) = covarPolY(1,0) = sumPolY[1];
1290 covarPolY(0,2) = covarPolY(2,0) = sumPolY[2];
1291 covarPolY(2,1) = covarPolY(1,2) = sumPolY[3];
1293 TMatrixD covarPolZ(2,2);
1294 covarPolZ(0,0) = sumPolZ[0]; covarPolZ(1,1) = sumPolZ[2];
1295 covarPolZ(1,0) = covarPolZ(0,1) = sumPolZ[1];
1298 // Update the tracklets
1299 Double_t x1, dy, dz;
1301 memset(cov, 0, sizeof(Double_t) * 15);
1302 for(Int_t iLayer = 0; iLayer < AliTRDtrackerV1::kNPlanes; iLayer++) {
1304 x = tracklets[iLayer].GetX0();
1310 memset(cov, 0, sizeof(Double_t) * 3);
1311 TMatrixD transform(3,3);
1314 transform(0,2) = x*x;
1318 TMatrixD covariance(transform, TMatrixD::kMult, covarPolY);
1319 covariance *= transform.T();
1320 TMatrixD transformZ(2,2);
1321 transformZ(0,0) = transformZ(1,1) = 1;
1322 transformZ(0,1) = x;
1323 TMatrixD covarZ(transformZ, TMatrixD::kMult, covarPolZ);
1324 covarZ *= transformZ.T();
1325 // y: R^2 = (x - x0)^2 + (y - y0)^2
1326 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1327 // R = Sqrt() = 1/Curvature
1328 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
1329 Double_t res = (x * a + b); // = (x - x0)/y0
1331 res = 1.0 - c * a + b * b - res; // = (R^2 - (x - x0)^2)/y0^2
1333 res = TMath::Sqrt(res);
1334 y = (1.0 - res) / a;
1336 cov[0] = covariance(0,0);
1337 cov[2] = covarZ(0,0);
1340 // dy: R^2 = (x - x0)^2 + (y - y0)^2
1341 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
1342 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1343 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
1344 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
1345 Double_t x0 = -b / a;
1346 if (-c * a + b * b + 1 > 0) {
1347 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
1348 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
1349 if (a < 0) yderiv *= -1.0;
1353 z = offset + slope * (x - xref);
1355 tracklets[iLayer].SetYref(0, y);
1356 tracklets[iLayer].SetYref(1, dy);
1357 tracklets[iLayer].SetZref(0, z);
1358 tracklets[iLayer].SetZref(1, dz);
1359 tracklets[iLayer].SetC(curvature);
1360 tracklets[iLayer].SetCovRef(cov);
1361 tracklets[iLayer].SetChi2(chi2track);
1364 /* if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >=5){
1365 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
1366 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
1367 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
1368 Double_t chi2z = CalculateChi2Z(tracklets, offset, slope, xref);
1369 cstreamer << "FitTiltedRieman0"
1370 << "EventNumber=" << eventNumber
1371 << "CandidateNumber=" << candidateNumber
1373 << "Chi2Z=" << chi2z
1380 //____________________________________________________________________
1381 Double_t AliTRDtrackerV1::FitLine(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t err, Int_t np, AliTrackPoint *points)
1384 // Fit track with a staight line
1385 // Fills an AliTrackPoint array with np points
1386 // Function should be used to refit tracks when no magnetic field was on
1388 AliTRDLeastSquare yfitter, zfitter;
1389 AliTRDcluster *cl = NULL;
1391 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1393 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1394 if(!(tracklet = track->GetTracklet(ipl))) continue;
1395 if(!tracklet->IsOK()) continue;
1396 new(&work[ipl]) AliTRDseedV1(*tracklet);
1398 tracklets = &work[0];
1401 Double_t xref = CalculateReferenceX(tracklets);
1402 Double_t x, y, z, dx, ye, yr, tilt;
1403 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1404 if(!tracklets[ipl].IsOK()) continue;
1405 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1406 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1407 if (!tracklets[ipl].IsUsable(itb)) continue;
1411 zfitter.AddPoint(&dx, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1415 Double_t z0 = zfitter.GetFunctionParameter(0);
1416 Double_t dzdx = zfitter.GetFunctionParameter(1);
1417 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1418 if(!tracklets[ipl].IsOK()) continue;
1419 for(Int_t itb = 0; itb < fgNTimeBins; itb++){
1420 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1421 if (!tracklets[ipl].IsUsable(itb)) continue;
1425 tilt = tracklets[ipl].GetTilt();
1427 yr = y + tilt*(z - z0 - dzdx*dx);
1428 // error definition changes for the different calls
1429 ye = tilt*TMath::Sqrt(cl->GetSigmaZ2());
1430 ye += err ? tracklets[ipl].GetSigmaY() : 0.2;
1431 yfitter.AddPoint(&dx, yr, ye);
1435 Double_t y0 = yfitter.GetFunctionParameter(0);
1436 Double_t dydx = yfitter.GetFunctionParameter(1);
1437 Double_t chi2 = 0.;//yfitter.GetChisquare()/Double_t(nPoints);
1439 //update track points array
1442 for(int ip=0; ip<np; ip++){
1443 points[ip].GetXYZ(xyz);
1444 xyz[1] = y0 + dydx * (xyz[0] - xref);
1445 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1446 points[ip].SetXYZ(xyz);
1453 //_________________________________________________________________________
1454 Double_t AliTRDtrackerV1::FitRiemanTilt(const AliTRDtrackV1 *track, AliTRDseedV1 *tracklets, Bool_t sigError, Int_t np, AliTrackPoint *points)
1457 // Performs a Riemann fit taking tilting pad correction into account
1459 // Paramters: - Array of tracklets (connected to the track candidate)
1460 // - Flag selecting the error definition
1461 // Output: - Chi2 values of the track (in Parameter list)
1463 // The equations which has to be solved simultaneously are:
1465 // R^{2} = (x-x_{0})^{2} + (y^{*}-y_{0})^{2}
1466 // y^{*} = y - tg(h)(z - z_{t})
1467 // z_{t} = z_{0}+dzdx*(x-x_{r})
1469 // with (x, y, z) the coordinate of the cluster, (x_0, y_0, z_0) the coordinate of the center of the Riemann circle,
1470 // R its radius, x_r a constant refrence radial position in the middle of the TRD stack and dzdx the slope of the
1471 // track in the x-z plane. Using the following transformations
1473 // t = 1 / (x^{2} + y^{2})
1475 // v = 2 * tan(h) * t
1476 // w = 2 * tan(h) * (x - x_{r}) * t
1478 // One gets the following linear equation
1480 // a + b * u + c * t + d * v + e * w = 2 * (y + tg(h) * z) * t
1482 // where the coefficients have the following meaning
1486 // c = (R^{2} -x_{0}^{2} - y_{0}^{2})/y_{0}
1490 // The error calculation for the free term is thus
1492 // #sigma = 2 * #sqrt{#sigma^{2}_{y} + (tilt corr ...) + tg^{2}(h) * #sigma^{2}_{z}} * t
1495 // From this simple model one can compute chi^2 estimates and a rough approximation of pt from the curvature according
1498 // C = 1/R = a/(1 + b^{2} + c*a)
1502 // M.Ivanov <M.Ivanov@gsi.de>
1503 // A.Bercuci <A.Bercuci@gsi.de>
1504 // M.Fasel <M.Fasel@gsi.de>
1506 TLinearFitter *fitter = GetTiltedRiemanFitter();
1507 fitter->StoreData(kTRUE);
1508 fitter->ClearPoints();
1509 AliTRDLeastSquare zfitter;
1510 AliTRDcluster *cl = NULL;
1512 AliTRDseedV1 work[kNPlanes], *tracklet = NULL;
1514 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1515 if(!(tracklet = track->GetTracklet(ipl))) continue;
1516 if(!tracklet->IsOK()) continue;
1517 new(&work[ipl]) AliTRDseedV1(*tracklet);
1519 tracklets = &work[0];
1522 Double_t xref = CalculateReferenceX(tracklets);
1523 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1524 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));
1525 Double_t x, y, z, t, tilt, dx, w, we;
1528 // Containers for Least-square fitter
1529 for(Int_t ipl = 0; ipl < kNPlanes; ipl++){
1530 if(!tracklets[ipl].IsOK()) continue;
1531 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
1532 if(!(cl = tracklets[ipl].GetClusters(itb))) continue;
1533 //if (!tracklets[ipl].IsUsable(itb)) continue;
1537 tilt = tracklets[ipl].GetTilt();
1541 uvt[0] = 2. * x * t;
1543 uvt[2] = 2. * tilt * t;
1544 uvt[3] = 2. * tilt * dx * t;
1545 w = 2. * (y + tilt*z) * t;
1546 // error definition changes for the different calls
1548 we *= sigError ? TMath::Sqrt(cl->GetSigmaY2()) : 0.2;
1549 fitter->AddPoint(uvt, w, we);
1550 zfitter.AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
1554 if(fitter->Eval()) return 1.E10;
1556 Double_t z0 = fitter->GetParameter(3);
1557 Double_t dzdx = fitter->GetParameter(4);
1560 // Linear fitter - not possible to make boundaries
1561 // Do not accept non possible z and dzdx combinations
1562 Bool_t accept = kTRUE;
1563 Double_t zref = 0.0;
1564 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
1565 if(!tracklets[iLayer].IsOK()) continue;
1566 zref = z0 + dzdx * (tracklets[iLayer].GetX0() - xref);
1567 if (TMath::Abs(tracklets[iLayer].GetZfit(0) - zref) > tracklets[iLayer].GetPadLength() * 0.5 + 1.0)
1572 Double_t dzmf = zfitter.GetFunctionParameter(1);
1573 Double_t zmf = zfitter.GetFunctionValue(&xref);
1574 fitter->FixParameter(3, zmf);
1575 fitter->FixParameter(4, dzmf);
1577 fitter->ReleaseParameter(3);
1578 fitter->ReleaseParameter(4);
1579 z0 = fitter->GetParameter(3); // = zmf ?
1580 dzdx = fitter->GetParameter(4); // = dzmf ?
1583 // Calculate Curvature
1584 Double_t a = fitter->GetParameter(0);
1585 Double_t b = fitter->GetParameter(1);
1586 Double_t c = fitter->GetParameter(2);
1587 Double_t y0 = 1. / a;
1588 Double_t x0 = -b * y0;
1589 Double_t tmp = y0*y0 + x0*x0 - c*y0;
1590 if(tmp<=0.) return 1.E10;
1591 Double_t radius = TMath::Sqrt(tmp);
1592 Double_t curvature = 1.0 + b*b - c*a;
1593 if (curvature > 0.0) curvature = a / TMath::Sqrt(curvature);
1595 // Calculate chi2 of the fit
1596 Double_t chi2 = fitter->GetChisquare()/Double_t(nPoints);
1597 AliDebugGeneral("AliTRDtrackerV1::FitRiemanTilt()", 4,
1598 Form("x0[%6.2f] y0[%6.2f] R[%6.2f] chi2[%f]\n", x0, y0, radius, chi2));
1600 // Update the tracklets
1602 for(Int_t ip = 0; ip < kNPlanes; ip++) {
1603 x = tracklets[ip].GetX0();
1604 tmp = radius*radius-(x-x0)*(x-x0);
1605 if(tmp <= 0.) continue;
1606 tmp = TMath::Sqrt(tmp);
1608 // y: R^2 = (x - x0)^2 + (y - y0)^2
1609 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
1610 tracklets[ip].SetYref(0, y0 - (y0>0.?1.:-1)*tmp);
1611 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
1612 tracklets[ip].SetYref(1, (x - x0) / tmp);
1613 tracklets[ip].SetZref(0, z0 + dzdx * (x - xref));
1614 tracklets[ip].SetZref(1, dzdx);
1615 tracklets[ip].SetC(curvature);
1616 tracklets[ip].SetChi2(chi2);
1619 //update track points array
1622 for(int ip=0; ip<np; ip++){
1623 points[ip].GetXYZ(xyz);
1624 xyz[1] = TMath::Abs(xyz[0] - x0) > radius ? 100. : y0 - (y0>0.?1.:-1.)*TMath::Sqrt((radius-(xyz[0]-x0))*(radius+(xyz[0]-x0)));
1625 xyz[2] = z0 + dzdx * (xyz[0] - xref);
1626 points[ip].SetXYZ(xyz);
1634 //____________________________________________________________________
1635 Double_t AliTRDtrackerV1::FitKalman(AliTRDtrackV1 *track, AliTRDseedV1 * const tracklets, Bool_t up, Int_t np, AliTrackPoint *points)
1637 // Kalman filter implementation for the TRD.
1638 // It returns the positions of the fit in the array "points"
1640 // Author : A.Bercuci@gsi.de
1642 // printf("Start track @ x[%f]\n", track->GetX());
1644 //prepare marker points along the track
1645 Int_t ip = np ? 0 : 1;
1647 if((up?-1:1) * (track->GetX() - points[ip].GetX()) > 0.) break;
1648 //printf("AliTRDtrackerV1::FitKalman() : Skip track marker x[%d] = %7.3f. Before track start ( %7.3f ).\n", ip, points[ip].GetX(), track->GetX());
1651 //if(points) printf("First marker point @ x[%d] = %f\n", ip, points[ip].GetX());
1654 AliTRDseedV1 tracklet, *ptrTracklet = NULL;
1656 //Loop through the TRD planes
1657 for (Int_t jplane = 0; jplane < kNPlanes; jplane++) {
1658 // GET TRACKLET OR BUILT IT
1659 Int_t iplane = up ? jplane : kNPlanes - 1 - jplane;
1661 if(!(ptrTracklet = &tracklets[iplane])) continue;
1663 if(!(ptrTracklet = track->GetTracklet(iplane))){
1664 /*AliTRDtrackerV1 *tracker = NULL;
1665 if(!(tracker = dynamic_cast<AliTRDtrackerV1*>( AliTRDrecoParam:Tracker()))) continue;
1666 ptrTracklet = new(&tracklet) AliTRDseedV1(iplane);
1667 if(!tracker->MakeTracklet(ptrTracklet, track)) */
1671 if(!ptrTracklet->IsOK()) continue;
1673 Double_t x = ptrTracklet->GetX0();
1676 //don't do anything if next marker is after next update point.
1677 if((up?-1:1) * (points[ip].GetX() - x) - fgkMaxStep < 0) break;
1678 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1680 Double_t xyz[3]; // should also get the covariance
1682 track->Global2LocalPosition(xyz, track->GetAlpha());
1683 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1686 // printf("plane[%d] tracklet[%p] x[%f]\n", iplane, ptrTracklet, x);
1688 // Propagate closer to the next update point
1689 if(((up?-1:1) * (x - track->GetX()) + fgkMaxStep < 0) && !PropagateToX(*track, x + (up?-1:1)*fgkMaxStep, fgkMaxStep)) return -1.;
1691 if(!AdjustSector(track)) return -1;
1692 if(TMath::Abs(track->GetSnp()) > fgkMaxSnp) return -1;
1694 //load tracklet to the tracker and the track
1696 if((index = FindTracklet(ptrTracklet)) < 0){
1697 ptrTracklet = SetTracklet(&tracklet);
1698 index = fTracklets->GetEntriesFast()-1;
1700 track->SetTracklet(ptrTracklet, index);*/
1703 // register tracklet to track with tracklet creation !!
1704 // PropagateBack : loaded tracklet to the tracker and update index
1705 // RefitInward : update index
1706 // MakeTrack : loaded tracklet to the tracker and update index
1707 if(!tracklets) track->SetTracklet(ptrTracklet, -1);
1710 //Calculate the mean material budget along the path inside the chamber
1711 Double_t xyz0[3]; track->GetXYZ(xyz0);
1712 Double_t alpha = track->GetAlpha();
1713 Double_t xyz1[3], y, z;
1714 if(!track->GetProlongation(x, y, z)) return -1;
1715 xyz1[0] = x * TMath::Cos(alpha) - y * TMath::Sin(alpha);
1716 xyz1[1] = +x * TMath::Sin(alpha) + y * TMath::Cos(alpha);
1718 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
1720 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param) <=0.) break;
1721 Double_t xrho = param[0]*param[4]; // density*length
1722 Double_t xx0 = param[1]; // radiation length
1724 //Propagate the track
1725 track->PropagateTo(x, xx0, xrho);
1726 if (!AdjustSector(track)) break;
1729 Double_t cov[3]; ptrTracklet->GetCovAt(x, cov);
1730 Double_t p[2] = { ptrTracklet->GetY(), ptrTracklet->GetZ()};
1731 Double_t chi2 = ((AliExternalTrackParam*)track)->GetPredictedChi2(p, cov);
1732 if(chi2<1e+10) track->Update(p, cov, chi2);
1735 //Reset material budget if 2 consecutive gold
1736 if(iplane>0 && track->GetTracklet(iplane-1) && ptrTracklet->GetN() + track->GetTracklet(iplane-1)->GetN() > 20) track->SetBudget(2, 0.);
1737 } // end planes loop
1741 if(((up?-1:1) * (points[ip].GetX() - track->GetX()) < 0) && !PropagateToX(*track, points[ip].GetX(), fgkMaxStep)) return -1.;
1743 Double_t xyz[3]; // should also get the covariance
1745 track->Global2LocalPosition(xyz, track->GetAlpha());
1746 points[ip].SetXYZ(xyz[0], xyz[1], xyz[2]);
1750 return track->GetChi2();
1753 //_________________________________________________________________________
1754 Float_t AliTRDtrackerV1::CalculateChi2Z(AliTRDseedV1 *tracklets, Double_t offset, Double_t slope, Double_t xref)
1757 // Calculates the chi2-value of the track in z-Direction including tilting pad correction.
1758 // A linear dependence on the x-value serves as a model.
1759 // The parameters are related to the tilted Riemann fit.
1760 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
1761 // - the offset for the reference x
1763 // - the reference x position
1764 // Output: - The Chi2 value of the track in z-Direction
1766 Float_t chi2Z = 0, nLayers = 0;
1767 for (Int_t iLayer = 0; iLayer < AliTRDgeometry::kNlayer; iLayer++) {
1768 if(!tracklets[iLayer].IsOK()) continue;
1769 Double_t z = offset + slope * (tracklets[iLayer].GetX0() - xref);
1770 chi2Z += TMath::Abs(tracklets[iLayer].GetZfit(0) - z);
1773 chi2Z /= TMath::Max((nLayers - 3.0),1.0);
1777 //_____________________________________________________________________________
1778 Int_t AliTRDtrackerV1::PropagateToX(AliTRDtrackV1 &t, Double_t xToGo, Double_t maxStep)
1781 // Starting from current X-position of track <t> this function
1782 // extrapolates the track up to radial position <xToGo>.
1783 // Returns 1 if track reaches the plane, and 0 otherwise
1786 const Double_t kEpsilon = 0.00001;
1788 // Current track X-position
1789 Double_t xpos = t.GetX();
1791 // Direction: inward or outward
1792 Double_t dir = (xpos < xToGo) ? 1.0 : -1.0;
1794 while (((xToGo - xpos) * dir) > kEpsilon) {
1803 // The next step size
1804 Double_t step = dir * TMath::Min(TMath::Abs(xToGo-xpos),maxStep);
1806 // Get the global position of the starting point
1809 // X-position after next step
1812 // Get local Y and Z at the X-position of the next step
1813 if(t.GetProlongation(x,y,z)<0) return 0; // No prolongation possible
1815 // The global position of the end point of this prolongation step
1816 xyz1[0] = x * TMath::Cos(t.GetAlpha()) - y * TMath::Sin(t.GetAlpha());
1817 xyz1[1] = +x * TMath::Sin(t.GetAlpha()) + y * TMath::Cos(t.GetAlpha());
1820 // Calculate the mean material budget between start and
1821 // end point of this prolongation step
1822 if(AliTracker::MeanMaterialBudget(xyz0, xyz1, param)<=0.) return 0;
1824 // Propagate the track to the X-position after the next step
1825 if (!t.PropagateTo(x, param[1], param[0]*param[4])) return 0;
1827 // Rotate the track if necessary
1830 // New track X-position
1840 //_____________________________________________________________________________
1841 Int_t AliTRDtrackerV1::ReadClusters(TClonesArray* &array, TTree *clusterTree) const
1844 // Reads AliTRDclusters from the file.
1845 // The names of the cluster tree and branches
1846 // should match the ones used in AliTRDclusterizer::WriteClusters()
1849 Int_t nsize = Int_t(clusterTree->GetTotBytes() / (sizeof(AliTRDcluster)));
1850 TObjArray *clusterArray = new TObjArray(nsize+1000);
1852 TBranch *branch = clusterTree->GetBranch("TRDcluster");
1854 AliError("Can't get the branch !");
1857 branch->SetAddress(&clusterArray);
1860 Float_t nclusters = fkReconstructor->GetRecoParam()->GetNClusters();
1861 if(fkReconstructor->IsHLT()) nclusters /= AliTRDgeometry::kNsector;
1862 array = new TClonesArray("AliTRDcluster", Int_t(nclusters));
1863 array->SetOwner(kTRUE);
1866 // Loop through all entries in the tree
1867 Int_t nEntries = (Int_t) clusterTree->GetEntries();
1870 AliTRDcluster *c = NULL;
1871 for (Int_t iEntry = 0; iEntry < nEntries; iEntry++) {
1873 nbytes += clusterTree->GetEvent(iEntry);
1875 // Get the number of points in the detector
1876 Int_t nCluster = clusterArray->GetEntriesFast();
1877 for (Int_t iCluster = 0; iCluster < nCluster; iCluster++) {
1878 if(!(c = (AliTRDcluster *) clusterArray->UncheckedAt(iCluster))) continue;
1879 new((*fClusters)[ncl++]) AliTRDcluster(*c);
1880 delete (clusterArray->RemoveAt(iCluster));
1884 delete clusterArray;
1889 //_____________________________________________________________________________
1890 Int_t AliTRDtrackerV1::LoadClusters(TTree *cTree)
1893 // Fills clusters into TRD tracking sectors
1896 if(!fkReconstructor->IsWritingClusters()){
1897 fClusters = AliTRDReconstructor::GetClusters();
1899 if (ReadClusters(fClusters, cTree)) {
1900 AliError("Problem with reading the clusters !");
1906 if(!fClusters || !fClusters->GetEntriesFast()){
1907 AliInfo("No TRD clusters");
1912 BuildTrackingContainers();
1914 //Int_t ncl = fClusters->GetEntriesFast();
1915 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1920 //_____________________________________________________________________________
1921 Int_t AliTRDtrackerV1::LoadClusters(TClonesArray * const clusters)
1924 // Fills clusters into TRD tracking sectors
1925 // Function for use in the HLT
1927 if(!clusters || !clusters->GetEntriesFast()){
1928 AliInfo("No TRD clusters");
1932 fClusters = clusters;
1936 BuildTrackingContainers();
1938 //Int_t ncl = fClusters->GetEntriesFast();
1939 //AliInfo(Form("Clusters %d [%6.2f %% in the active volume]", ncl, 100.*float(nin)/ncl));
1945 //____________________________________________________________________
1946 Int_t AliTRDtrackerV1::BuildTrackingContainers()
1948 // Building tracking containers for clusters
1950 Int_t nin =0, icl = fClusters->GetEntriesFast();
1952 AliTRDcluster *c = (AliTRDcluster *) fClusters->UncheckedAt(icl);
1953 if(c->IsInChamber()) nin++;
1954 if(fkReconstructor->IsHLT()) c->SetRPhiMethod(AliTRDcluster::kCOG);
1955 Int_t detector = c->GetDetector();
1956 Int_t sector = fGeom->GetSector(detector);
1957 Int_t stack = fGeom->GetStack(detector);
1958 Int_t layer = fGeom->GetLayer(detector);
1960 fTrSec[sector].GetChamber(stack, layer, kTRUE)->InsertCluster(c, icl);
1963 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
1964 for(int isector =0; isector<AliTRDgeometry::kNsector; isector++){
1965 if(!fTrSec[isector].GetNChambers()) continue;
1966 fTrSec[isector].Init(fkReconstructor, cal);
1974 //____________________________________________________________________
1975 void AliTRDtrackerV1::UnloadClusters()
1978 // Clears the arrays of clusters and tracks. Resets sectors and timebins
1979 // If option "force" is also set the containers are also deleted. This is useful
1984 if(HasRemoveContainers()){delete fTracks; fTracks = NULL;}
1987 fTracklets->Delete();
1988 if(HasRemoveContainers()){delete fTracklets; fTracklets = NULL;}
1991 if(IsClustersOwner()) fClusters->Delete();
1993 // save clusters array in the reconstructor for further use.
1994 if(!fkReconstructor->IsWritingClusters()){
1995 AliTRDReconstructor::SetClusters(fClusters);
1996 SetClustersOwner(kFALSE);
1997 } else AliTRDReconstructor::SetClusters(NULL);
2000 for (int i = 0; i < AliTRDgeometry::kNsector; i++) fTrSec[i].Clear();
2002 // Increment the Event Number
2003 AliTRDtrackerDebug::SetEventNumber(AliTRDtrackerDebug::GetEventNumber() + 1);
2006 // //____________________________________________________________________
2007 // void AliTRDtrackerV1::UseClusters(const AliKalmanTrack *t, Int_t) const
2009 // const AliTRDtrackV1 *track = dynamic_cast<const AliTRDtrackV1*>(t);
2010 // if(!track) return;
2012 // AliTRDseedV1 *tracklet = NULL;
2013 // for(Int_t ily=AliTRDgeometry::kNlayer; ily--;){
2014 // if(!(tracklet = track->GetTracklet(ily))) continue;
2015 // AliTRDcluster *c = NULL;
2016 // for(Int_t ic=AliTRDseed::kNclusters; ic--;){
2017 // if(!(c=tracklet->GetClusters(ic))) continue;
2024 //_____________________________________________________________________________
2025 Bool_t AliTRDtrackerV1::AdjustSector(AliTRDtrackV1 *const track)
2028 // Rotates the track when necessary
2031 Double_t alpha = AliTRDgeometry::GetAlpha();
2032 Double_t y = track->GetY();
2033 Double_t ymax = track->GetX()*TMath::Tan(0.5*alpha);
2036 if (!track->Rotate( alpha)) {
2040 else if (y < -ymax) {
2041 if (!track->Rotate(-alpha)) {
2051 //____________________________________________________________________
2052 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(AliTRDtrackV1 *const track, Int_t p, Int_t &idx)
2054 // Find tracklet for TRD track <track>
2063 // Detailed description
2065 idx = track->GetTrackletIndex(p);
2066 AliTRDseedV1 *tracklet = (idx<0) ? NULL : (AliTRDseedV1*)fTracklets->UncheckedAt(idx);
2071 //____________________________________________________________________
2072 AliTRDseedV1* AliTRDtrackerV1::SetTracklet(const AliTRDseedV1 * const tracklet)
2074 // Add this tracklet to the list of tracklets stored in the tracker
2077 // - tracklet : pointer to the tracklet to be added to the list
2080 // - the index of the new tracklet in the tracker tracklets list
2082 // Detailed description
2083 // Build the tracklets list if it is not yet created (late initialization)
2084 // and adds the new tracklet to the list.
2087 fTracklets = new TClonesArray("AliTRDseedV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2088 fTracklets->SetOwner(kTRUE);
2090 Int_t nentries = fTracklets->GetEntriesFast();
2091 return new ((*fTracklets)[nentries]) AliTRDseedV1(*tracklet);
2094 //____________________________________________________________________
2095 AliTRDtrackV1* AliTRDtrackerV1::SetTrack(const AliTRDtrackV1 * const track)
2097 // Add this track to the list of tracks stored in the tracker
2100 // - track : pointer to the track to be added to the list
2103 // - the pointer added
2105 // Detailed description
2106 // Build the tracks list if it is not yet created (late initialization)
2107 // and adds the new track to the list.
2110 fTracks = new TClonesArray("AliTRDtrackV1", AliTRDgeometry::Nsector()*kMaxTracksStack);
2111 fTracks->SetOwner(kTRUE);
2113 Int_t nentries = fTracks->GetEntriesFast();
2114 return new ((*fTracks)[nentries]) AliTRDtrackV1(*track);
2119 //____________________________________________________________________
2120 Int_t AliTRDtrackerV1::Clusters2TracksSM(Int_t sector, AliESDEvent *esd)
2123 // Steer tracking for one SM.
2126 // sector : Array of (SM) propagation layers containing clusters
2127 // esd : The current ESD event. On output it contains the also
2128 // the ESD (TRD) tracks found in this SM.
2131 // Number of tracks found in this TRD supermodule.
2133 // Detailed description
2135 // 1. Unpack AliTRDpropagationLayers objects for each stack.
2136 // 2. Launch stack tracking.
2137 // See AliTRDtrackerV1::Clusters2TracksStack() for details.
2138 // 3. Pack results in the ESD event.
2142 Int_t nChambers = 0;
2143 AliTRDtrackingChamber **stack = NULL, *chamber = NULL;
2144 for(int istack = 0; istack<AliTRDgeometry::kNstack; istack++){
2145 if(!(stack = fTrSec[sector].GetStack(istack))) continue;
2147 for(int ilayer=0; ilayer<AliTRDgeometry::kNlayer; ilayer++){
2148 if(!(chamber = stack[ilayer])) continue;
2149 if(chamber->GetNClusters() < fgNTimeBins * fkReconstructor->GetRecoParam() ->GetFindableClusters()) continue;
2151 //AliInfo(Form("sector %d stack %d layer %d clusters %d", sector, istack, ilayer, chamber->GetNClusters()));
2153 if(nChambers < 4) continue;
2154 //AliInfo(Form("Doing stack %d", istack));
2155 nTracks += Clusters2TracksStack(stack, fTracksESD);
2157 if(nTracks) AliDebug(2, Form("Number of tracks: SM_%02d[%d]", sector, nTracks));
2159 for(int itrack=0; itrack<nTracks; itrack++){
2160 AliESDtrack *esdTrack((AliESDtrack*)(fTracksESD->operator[](itrack)));
2161 Int_t id = esd->AddTrack(esdTrack);
2163 // set ESD id to stand alone TRD tracks
2164 if (fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2165 esdTrack=esd->GetTrack(id);
2166 TObject *o(NULL); Int_t ic(0);
2167 AliTRDtrackV1 *calibTrack(NULL);
2168 while((o = esdTrack->GetCalibObject(ic++))){
2169 if(!(calibTrack = dynamic_cast<AliTRDtrackV1*>(o))) continue;
2170 calibTrack->SetESDid(esdTrack->GetID());
2176 // Reset Track and Candidate Number
2177 AliTRDtrackerDebug::SetCandidateNumber(0);
2178 AliTRDtrackerDebug::SetTrackNumber(0);
2180 // delete ESD tracks in the array
2181 fTracksESD->Delete();
2185 //____________________________________________________________________
2186 Int_t AliTRDtrackerV1::Clusters2TracksStack(AliTRDtrackingChamber **stack, TClonesArray * const esdTrackList)
2189 // Make tracks in one TRD stack.
2192 // layer : Array of stack propagation layers containing clusters
2193 // esdTrackList : Array of ESD tracks found by the stand alone tracker.
2194 // On exit the tracks found in this stack are appended.
2197 // Number of tracks found in this stack.
2199 // Detailed description
2201 // 1. Find the 3 most useful seeding chambers. See BuildSeedingConfigs() for details.
2202 // 2. Steer AliTRDtrackerV1::MakeSeeds() for 3 seeding layer configurations.
2203 // See AliTRDtrackerV1::MakeSeeds() for more details.
2204 // 3. Arrange track candidates in decreasing order of their quality
2205 // 4. Classify tracks in 5 categories according to:
2206 // a) number of layers crossed
2208 // 5. Sign clusters by tracks in decreasing order of track quality
2209 // 6. Build AliTRDtrack out of seeding tracklets
2211 // 8. Build ESD track and register it to the output list
2214 const AliTRDCalDet *cal = AliTRDcalibDB::Instance()->GetT0Det();
2215 AliTRDtrackingChamber *chamber = NULL;
2216 AliTRDtrackingChamber **ci = NULL;
2217 AliTRDseedV1 sseed[kMaxTracksStack*6]; // to be initialized
2218 Int_t pars[4]; // MakeSeeds parameters
2220 //Double_t alpha = AliTRDgeometry::GetAlpha();
2221 //Double_t shift = .5 * alpha;
2222 Int_t configs[kNConfigs];
2224 // Purge used clusters from the containers
2226 for(Int_t ic = kNPlanes; ic--; ci++){
2227 if(!(*ci)) continue;
2231 // Build initial seeding configurations
2232 Double_t quality = BuildSeedingConfigs(stack, configs);
2233 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2234 AliInfo(Form("Plane config %d %d %d Quality %f"
2235 , configs[0], configs[1], configs[2], quality));
2239 // Initialize contors
2240 Int_t ntracks, // number of TRD track candidates
2241 ntracks1, // number of registered TRD tracks/iter
2242 ntracks2 = 0; // number of all registered TRD tracks in stack
2246 Int_t ic = 0; ci = &stack[0];
2247 while(ic<kNPlanes && !(*ci)){ic++; ci++;}
2248 if(!(*ci)) return ntracks2;
2249 Int_t istack = fGeom->GetStack((*ci)->GetDetector());
2252 // Loop over seeding configurations
2253 ntracks = 0; ntracks1 = 0;
2254 for (Int_t iconf = 0; iconf<3; iconf++) {
2255 pars[0] = configs[iconf];
2258 ntracks = MakeSeeds(stack, &sseed[6*ntracks], pars);
2259 //AliInfo(Form("Number of Tracks after iteration step %d: %d\n", iconf, ntracks));
2260 if(ntracks == kMaxTracksStack) break;
2262 AliDebug(2, Form("Candidate TRD tracks %d in iteration %d.", ntracks, fSieveSeeding));
2266 // Sort the seeds according to their quality
2267 Int_t sort[kMaxTracksStack];
2268 TMath::Sort(ntracks, fTrackQuality, sort, kTRUE);
2270 // Initialize number of tracks so far and logic switches
2271 Int_t ntracks0 = esdTrackList->GetEntriesFast();
2272 Bool_t signedTrack[kMaxTracksStack];
2273 Bool_t fakeTrack[kMaxTracksStack];
2274 for (Int_t i=0; i<ntracks; i++){
2275 signedTrack[i] = kFALSE;
2276 fakeTrack[i] = kFALSE;
2278 //AliInfo("Selecting track candidates ...");
2280 // Sieve clusters in decreasing order of track quality
2281 Double_t trackParams[7];
2282 // AliTRDseedV1 *lseed = NULL;
2283 Int_t jSieve = 0, candidates;
2285 //AliInfo(Form("\t\tITER = %i ", jSieve));
2287 // Check track candidates
2289 for (Int_t itrack = 0; itrack < ntracks; itrack++) {
2290 Int_t trackIndex = sort[itrack];
2291 if (signedTrack[trackIndex] || fakeTrack[trackIndex]) continue;
2294 // Calculate track parameters from tracklets seeds
2299 for (Int_t jLayer = 0; jLayer < kNPlanes; jLayer++) {
2300 Int_t jseed = kNPlanes*trackIndex+jLayer;
2301 if(!sseed[jseed].IsOK()) continue;
2302 if (TMath::Abs(sseed[jseed].GetYref(0) / sseed[jseed].GetX0()) < 0.158) findable++;
2303 // TODO here we get a sig fault which should never happen !
2304 sseed[jseed].UpdateUsed();
2305 ncl += sseed[jseed].GetN2();
2306 nused += sseed[jseed].GetNUsed();
2310 // Filter duplicated tracks
2312 //printf("Skip %d nused %d\n", trackIndex, nused);
2313 fakeTrack[trackIndex] = kTRUE;
2316 if (ncl>0 && Float_t(nused)/ncl >= .25){
2317 //printf("Skip %d nused/ncl >= .25\n", trackIndex);
2318 fakeTrack[trackIndex] = kTRUE;
2323 Bool_t skip = kFALSE;
2326 if(nlayers < 6) {skip = kTRUE; break;}
2327 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2331 if(nlayers < findable){skip = kTRUE; break;}
2332 if(TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -4.){skip = kTRUE; break;}
2336 if ((nlayers == findable) || (nlayers == 6)) { skip = kTRUE; break;}
2337 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -6.0){skip = kTRUE; break;}
2341 if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) < -5.){skip = kTRUE; break;}
2345 if (nlayers == 3){skip = kTRUE; break;}
2346 //if (TMath::Log(1.E-9+fTrackQuality[trackIndex]) - nused/(nlayers-3.0) < -15.0){skip = kTRUE; break;}
2351 AliDebug(4, Form("REJECTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2353 } else AliDebug(4, Form("ACCEPTED : %d idx[%d] quality[%e] tracklets[%d] usedClusters[%d]", itrack, trackIndex, fTrackQuality[trackIndex], nlayers, nused));
2355 signedTrack[trackIndex] = kTRUE;
2357 // Build track parameters
2358 AliTRDseedV1 *lseed =&sseed[trackIndex*6];
2360 while(idx<3 && !lseed->IsOK()) {
2364 Double_t x = lseed->GetX0();// - 3.5;
2365 trackParams[0] = x; //NEW AB
2366 trackParams[1] = lseed->GetYref(0); // lseed->GetYat(x);
2367 trackParams[2] = lseed->GetZref(0); // lseed->GetZat(x);
2368 trackParams[3] = TMath::Sin(TMath::ATan(lseed->GetYref(1)));
2369 trackParams[4] = lseed->GetZref(1) / TMath::Sqrt(1. + lseed->GetYref(1) * lseed->GetYref(1));
2370 trackParams[5] = lseed->GetC();
2371 Int_t ich = 0; while(!(chamber = stack[ich])) ich++;
2372 trackParams[6] = fGeom->GetSector(chamber->GetDetector());/* *alpha+shift; // Supermodule*/
2374 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 1 && fkReconstructor->IsDebugStreaming()){
2375 //AliInfo(Form("Track %d [%d] nlayers %d trackQuality = %e nused %d, yref = %3.3f", itrack, trackIndex, nlayers, fTrackQuality[trackIndex], nused, trackParams[1]));
2377 AliTRDseedV1 *dseed[6];
2378 for(Int_t iseed = AliTRDgeometry::kNlayer; iseed--;) dseed[iseed] = new AliTRDseedV1(lseed[iseed]);
2380 //Int_t eventNrInFile = esd->GetEventNumberInFile();
2381 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2382 Int_t trackNumber = AliTRDtrackerDebug::GetTrackNumber();
2383 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2384 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2385 cstreamer << "Clusters2TracksStack"
2386 << "EventNumber=" << eventNumber
2387 << "TrackNumber=" << trackNumber
2388 << "CandidateNumber=" << candidateNumber
2389 << "Iter=" << fSieveSeeding
2390 << "Like=" << fTrackQuality[trackIndex]
2391 << "S0.=" << dseed[0]
2392 << "S1.=" << dseed[1]
2393 << "S2.=" << dseed[2]
2394 << "S3.=" << dseed[3]
2395 << "S4.=" << dseed[4]
2396 << "S5.=" << dseed[5]
2397 << "p0=" << trackParams[0]
2398 << "p1=" << trackParams[1]
2399 << "p2=" << trackParams[2]
2400 << "p3=" << trackParams[3]
2401 << "p4=" << trackParams[4]
2402 << "p5=" << trackParams[5]
2403 << "p6=" << trackParams[6]
2405 << "NLayers=" << nlayers
2406 << "Findable=" << findable
2407 << "NUsed=" << nused
2411 AliTRDtrackV1 *track = MakeTrack(&sseed[trackIndex*kNPlanes], trackParams);
2413 AliDebug(1, "Track building failed.");
2417 //AliInfo("End of MakeTrack()");
2418 AliESDtrack *esdTrack = new ((*esdTrackList)[ntracks0++]) AliESDtrack();
2419 esdTrack->UpdateTrackParams(track, AliESDtrack::kTRDout);
2420 esdTrack->SetLabel(track->GetLabel());
2421 track->UpdateESDtrack(esdTrack);
2422 // write ESD-friends if neccessary
2423 if (fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 0){
2424 AliTRDtrackV1 *calibTrack = new AliTRDtrackV1(*track);
2425 calibTrack->SetOwner();
2426 esdTrack->AddCalibObject(calibTrack);
2429 AliTRDtrackerDebug::SetTrackNumber(AliTRDtrackerDebug::GetTrackNumber() + 1);
2433 } while(jSieve<5 && candidates); // end track candidates sieve
2434 if(!ntracks1) break;
2436 // increment counters
2437 ntracks2 += ntracks1;
2439 if(fkReconstructor->IsHLT()) break;
2442 // Rebuild plane configurations and indices taking only unused clusters into account
2443 quality = BuildSeedingConfigs(stack, configs);
2444 if(quality < 1.E-7) break; //fkReconstructor->GetRecoParam() ->GetPlaneQualityThreshold()) break;
2446 for(Int_t ip = 0; ip < kNPlanes; ip++){
2447 if(!(chamber = stack[ip])) continue;
2448 chamber->Build(fGeom, cal);//Indices(fSieveSeeding);
2451 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 10){
2452 AliInfo(Form("Sieve level %d Plane config %d %d %d Quality %f", fSieveSeeding, configs[0], configs[1], configs[2], quality));
2454 } while(fSieveSeeding<10); // end stack clusters sieve
2458 //AliInfo(Form("Registered TRD tracks %d in stack %d.", ntracks2, pars[1]));
2463 //___________________________________________________________________
2464 Double_t AliTRDtrackerV1::BuildSeedingConfigs(AliTRDtrackingChamber **stack, Int_t *configs)
2467 // Assign probabilities to chambers according to their
2468 // capability of producing seeds.
2472 // layers : Array of stack propagation layers for all 6 chambers in one stack
2473 // configs : On exit array of configuration indexes (see GetSeedingConfig()
2474 // for details) in the decreasing order of their seeding probabilities.
2478 // Return top configuration quality
2480 // Detailed description:
2482 // To each chamber seeding configuration (see GetSeedingConfig() for
2483 // the list of all configurations) one defines 2 quality factors:
2484 // - an apriori topological quality (see GetSeedingConfig() for details) and
2485 // - a data quality based on the uniformity of the distribution of
2486 // clusters over the x range (time bins population). See CookChamberQA() for details.
2487 // The overall chamber quality is given by the product of this 2 contributions.
2490 Double_t chamberQ[kNPlanes];memset(chamberQ, 0, kNPlanes*sizeof(Double_t));
2491 AliTRDtrackingChamber *chamber = NULL;
2492 for(int iplane=0; iplane<kNPlanes; iplane++){
2493 if(!(chamber = stack[iplane])) continue;
2494 chamberQ[iplane] = (chamber = stack[iplane]) ? chamber->GetQuality() : 0.;
2497 Double_t tconfig[kNConfigs];memset(tconfig, 0, kNConfigs*sizeof(Double_t));
2498 Int_t planes[] = {0, 0, 0, 0};
2499 for(int iconf=0; iconf<kNConfigs; iconf++){
2500 GetSeedingConfig(iconf, planes);
2501 tconfig[iconf] = fgTopologicQA[iconf];
2502 for(int iplane=0; iplane<4; iplane++) tconfig[iconf] *= chamberQ[planes[iplane]];
2505 TMath::Sort((Int_t)kNConfigs, tconfig, configs, kTRUE);
2506 // AliInfo(Form("q[%d] = %f", configs[0], tconfig[configs[0]]));
2507 // AliInfo(Form("q[%d] = %f", configs[1], tconfig[configs[1]]));
2508 // AliInfo(Form("q[%d] = %f", configs[2], tconfig[configs[2]]));
2510 return tconfig[configs[0]];
2513 //____________________________________________________________________
2514 Int_t AliTRDtrackerV1::MakeSeeds(AliTRDtrackingChamber **stack, AliTRDseedV1 * const sseed, const Int_t * const ipar)
2517 // Seed tracklets and build candidate TRD tracks. The procedure is used during barrel tracking to account for tracks which are
2518 // either missed by TPC prolongation or conversions inside the TRD volume.
2519 // For stand alone tracking the procedure is used to estimate all tracks measured by TRD.
2522 // layers : Array of stack propagation layers containing clusters
2523 // sseed : Array of empty tracklet seeds. On exit they are filled.
2524 // ipar : Control parameters:
2525 // ipar[0] -> seeding chambers configuration
2526 // ipar[1] -> stack index
2527 // ipar[2] -> number of track candidates found so far
2530 // Number of tracks candidates found.
2532 // The following steps are performed:
2533 // 1. Build seeding layers by collapsing all time bins from each of the four seeding chambers along the
2534 // radial coordinate. See AliTRDtrackingChamber::GetSeedingLayer() for details. The chambers selection for seeding
2535 // is described in AliTRDtrackerV1::Clusters2TracksStack().
2536 // 2. Using the seeding clusters from the seeding layer (step 1) build combinatorics using the following algorithm:
2537 // - for each seeding cluster in the lower seeding layer find
2538 // - all seeding clusters in the upper seeding layer inside a road defined by a given phi angle. The angle
2539 // is calculated on the minimum pt of tracks from vertex accesible to the stand alone tracker.
2540 // - for each pair of two extreme seeding clusters select middle upper cluster using roads defined externally by the
2542 // - select last seeding cluster as the nearest to the linear approximation of the track described by the first three
2543 // seeding clusters.
2544 // The implementation of road calculation and cluster selection can be found in the functions AliTRDchamberTimeBin::BuildCond()
2545 // and AliTRDchamberTimeBin::GetClusters().
2546 // 3. Helix fit of the seeding clusters set. (see AliTRDtrackerFitter::FitRieman(AliTRDcluster**)). No tilt correction is
2547 // performed at this level
2548 // 4. Initialize seeding tracklets in the seeding chambers.
2549 // 5. *Filter 0* Chi2 cut on the Y and Z directions. The threshold is set externally by the reco params.
2550 // 6. Attach (true) clusters to seeding tracklets (see AliTRDseedV1::AttachClusters()) and fit tracklet (see
2551 // AliTRDseedV1::Fit()). The number of used clusters used by current seeds should not exceed ... (25).
2552 // 7. *Filter 1* Check if all 4 seeding tracklets are correctly constructed.
2553 // 8. Helix fit of the clusters from the seeding tracklets with tilt correction. Refit tracklets using the new
2554 // approximation of the track.
2555 // 9. *Filter 2* Calculate likelihood of the track. (See AliTRDtrackerV1::CookLikelihood()). The following quantities are
2556 // checked against the Riemann fit:
2557 // - position resolution in y
2558 // - angular resolution in the bending plane
2559 // - likelihood of the number of clusters attached to the tracklet
2560 // 10. Extrapolation of the helix fit to the other 2 chambers *non seeding* chambers:
2561 // - Initialization of extrapolation tracklets with the fit parameters
2562 // - Attach clusters to extrapolated tracklets
2563 // - Helix fit of tracklets
2564 // 11. Improve seeding tracklets quality by reassigning clusters based on the last parameters of the track
2565 // See AliTRDtrackerV1::ImproveSeedQuality() for details.
2566 // 12. Helix fit of all 6 seeding tracklets and chi2 calculation
2567 // 13. Hyperplane fit and track quality calculation. See AliTRDtrackerFitter::FitHyperplane() for details.
2568 // 14. Cooking labels for tracklets. Should be done only for MC
2569 // 15. Register seeds.
2572 // Marian Ivanov <M.Ivanov@gsi.de>
2573 // Alexandru Bercuci <A.Bercuci@gsi.de>
2574 // Markus Fasel <M.Fasel@gsi.de>
2576 AliTRDtrackingChamber *chamber = NULL;
2577 AliTRDcluster *c[kNSeedPlanes] = {NULL, NULL, NULL, NULL}; // initilize seeding clusters
2578 AliTRDseedV1 *cseed = &sseed[0]; // initialize tracklets for first track
2579 Int_t ncl, mcl; // working variable for looping over clusters
2580 Int_t index[AliTRDchamberTimeBin::kMaxClustersLayer], jndex[AliTRDchamberTimeBin::kMaxClustersLayer];
2582 // chi2[0] = tracklet chi2 on the Z direction
2583 // chi2[1] = tracklet chi2 on the R direction
2586 // this should be data member of AliTRDtrack TODO
2587 Double_t seedQuality[kMaxTracksStack];
2589 // unpack control parameters
2590 Int_t config = ipar[0];
2591 Int_t ntracks = ipar[1];
2592 Int_t istack = ipar[2];
2593 Int_t planes[kNSeedPlanes]; GetSeedingConfig(config, planes);
2594 Int_t planesExt[kNPlanes-kNSeedPlanes]; GetExtrapolationConfig(config, planesExt);
2597 // Init chambers geometry
2598 Double_t hL[kNPlanes]; // Tilting angle
2599 Float_t padlength[kNPlanes]; // pad lenghts
2600 Float_t padwidth[kNPlanes]; // pad widths
2601 AliTRDpadPlane *pp = NULL;
2602 for(int iplane=0; iplane<kNPlanes; iplane++){
2603 pp = fGeom->GetPadPlane(iplane, istack);
2604 hL[iplane] = TMath::Tan(TMath::DegToRad()*pp->GetTiltingAngle());
2605 padlength[iplane] = pp->GetLengthIPad();
2606 padwidth[iplane] = pp->GetWidthIPad();
2609 // Init anode wire position for chambers
2610 Double_t x0[kNPlanes], // anode wire position
2611 driftLength = .5*AliTRDgeometry::AmThick() - AliTRDgeometry::DrThick(); // drift length
2612 TGeoHMatrix *matrix = NULL;
2613 Double_t loc[] = {AliTRDgeometry::AnodePos(), 0., 0.};
2614 Double_t glb[] = {0., 0., 0.};
2615 AliTRDtrackingChamber **cIter = &stack[0];
2616 for(int iLayer=0; iLayer<kNPlanes; iLayer++,cIter++){
2617 if(!(*cIter)) continue;
2618 if(!(matrix = fGeom->GetClusterMatrix((*cIter)->GetDetector()))){
2620 x0[iLayer] = fgkX0[iLayer];
2622 matrix->LocalToMaster(loc, glb);
2623 x0[iLayer] = glb[0];
2626 AliDebug(2, Form("Making seeds Stack[%d] Config[%d] Tracks[%d]...", istack, config, ntracks));
2628 // Build seeding layers
2631 for(int isl=0; isl<kNSeedPlanes; isl++){
2632 if(!(chamber = stack[planes[isl]])) continue;
2633 if(!chamber->GetSeedingLayer(fSeedTB[isl], fGeom, fkReconstructor)) continue;
2636 if(nlayers < kNSeedPlanes) return ntracks;
2639 // Start finding seeds
2640 Double_t cond0[4], cond1[4], cond2[4];
2642 while((c[3] = (*fSeedTB[3])[icl++])){
2644 fSeedTB[0]->BuildCond(c[3], cond0, 0);
2645 fSeedTB[0]->GetClusters(cond0, index, ncl);
2646 //printf("Found c[3] candidates 0 %d\n", ncl);
2649 c[0] = (*fSeedTB[0])[index[jcl++]];
2651 Double_t dx = c[3]->GetX() - c[0]->GetX();
2652 Double_t dzdx = (c[3]->GetZ() - c[0]->GetZ())/dx;
2653 Double_t dydx = (c[3]->GetY() - c[0]->GetY())/dx;
2654 fSeedTB[1]->BuildCond(c[0], cond1, 1, dzdx, dydx);
2655 fSeedTB[1]->GetClusters(cond1, jndex, mcl);
2656 //printf("Found c[0] candidates 1 %d\n", mcl);
2660 c[1] = (*fSeedTB[1])[jndex[kcl++]];
2662 fSeedTB[2]->BuildCond(c[1], cond2, 2, dzdx, dydx);
2663 c[2] = fSeedTB[2]->GetNearestCluster(cond2);
2664 //printf("Found c[1] candidate 2 %p\n", c[2]);
2667 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].",
2668 c[0]->GetX(), c[0]->GetY(), c[0]->GetZ(),
2669 c[1]->GetX(), c[1]->GetY(), c[1]->GetZ(),
2670 c[2]->GetX(), c[2]->GetY(), c[2]->GetZ(),
2671 c[3]->GetX(), c[3]->GetY(), c[3]->GetZ()));
2673 for (Int_t il = 0; il < kNPlanes; il++) cseed[il].Reset();
2677 AliTRDseedV1 *tseed = &cseed[0];
2679 for(int iLayer=0; iLayer<kNPlanes; iLayer++, tseed++, cIter++){
2680 Int_t det = (*cIter) ? (*cIter)->GetDetector() : -1;
2681 tseed->SetDetector(det);
2682 tseed->SetTilt(hL[iLayer]);
2683 tseed->SetPadLength(padlength[iLayer]);
2684 tseed->SetPadWidth(padwidth[iLayer]);
2685 tseed->SetReconstructor(fkReconstructor);
2686 tseed->SetX0(det<0 ? fR[iLayer]+driftLength : x0[iLayer]);
2687 tseed->Init(GetRiemanFitter());
2688 tseed->SetStandAlone(kTRUE);
2691 Bool_t isFake = kFALSE;
2692 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2693 if (c[0]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2694 if (c[1]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2695 if (c[2]->GetLabel(0) != c[3]->GetLabel(0)) isFake = kTRUE;
2698 for(Int_t l = 0; l < kNSeedPlanes; l++) xpos[l] = fSeedTB[l]->GetX();
2700 for(int il=0; il<4; il++) yref[il] = cseed[planes[il]].GetYref(0);
2701 Int_t ll = c[3]->GetLabel(0);
2702 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2703 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2704 AliRieman *rim = GetRiemanFitter();
2705 TTreeSRedirector &cs0 = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2707 <<"EventNumber=" << eventNumber
2708 <<"CandidateNumber=" << candidateNumber
2709 <<"isFake=" << isFake
2710 <<"config=" << config
2712 <<"chi2z=" << chi2[0]
2713 <<"chi2y=" << chi2[1]
2714 <<"Y2exp=" << cond2[0]
2715 <<"Z2exp=" << cond2[1]
2716 <<"X0=" << xpos[0] //layer[sLayer]->GetX()
2717 <<"X1=" << xpos[1] //layer[sLayer + 1]->GetX()
2718 <<"X2=" << xpos[2] //layer[sLayer + 2]->GetX()
2719 <<"X3=" << xpos[3] //layer[sLayer + 3]->GetX()
2720 <<"yref0=" << yref[0]
2721 <<"yref1=" << yref[1]
2722 <<"yref2=" << yref[2]
2723 <<"yref3=" << yref[3]
2728 <<"Seed0.=" << &cseed[planes[0]]
2729 <<"Seed1.=" << &cseed[planes[1]]
2730 <<"Seed2.=" << &cseed[planes[2]]
2731 <<"Seed3.=" << &cseed[planes[3]]
2732 <<"RiemanFitter.=" << rim
2735 if(chi2[0] > fkReconstructor->GetRecoParam() ->GetChi2Z()/*7./(3. - sLayer)*//*iter*/){
2736 AliDebug(3, Form("Filter on chi2Z [%f].", chi2[0]));
2737 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2740 if(chi2[1] > fkReconstructor->GetRecoParam() ->GetChi2Y()/*1./(3. - sLayer)*//*iter*/){
2741 AliDebug(3, Form("Filter on chi2Y [%f].", chi2[1]));
2742 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2745 //AliInfo("Passed chi2 filter.");
2747 // try attaching clusters to tracklets
2749 AliTRDcluster *cl = NULL;
2750 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2751 Int_t jLayer = planes[iLayer];
2752 Int_t nNotInChamber = 0;
2753 if(!cseed[jLayer].AttachClusters(stack[jLayer], kTRUE)) continue;
2754 if(/*fkReconstructor->IsHLT()*/kFALSE){
2755 cseed[jLayer].UpdateUsed();
2756 if(!cseed[jLayer].IsOK()) continue;
2758 cseed[jLayer].Fit();
2759 cseed[jLayer].UpdateUsed();
2760 cseed[jLayer].ResetClusterIter();
2761 while((cl = cseed[jLayer].NextCluster())){
2762 if(!cl->IsInChamber()) nNotInChamber++;
2764 //printf("clusters[%d], used[%d], not in chamber[%d]\n", cseed[jLayer].GetN(), cseed[jLayer].GetNUsed(), nNotInChamber);
2765 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
2770 if(mlayers < kNSeedPlanes){
2771 AliDebug(2, Form("Found only %d tracklets out of %d. Skip.", mlayers, kNSeedPlanes));
2772 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2776 // temporary exit door for the HLT
2777 if(fkReconstructor->IsHLT()){
2778 // attach clusters to extrapolation chambers
2779 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2780 Int_t jLayer = planesExt[iLayer];
2781 if(!(chamber = stack[jLayer])) continue;
2782 if(!cseed[jLayer].AttachClusters(chamber, kTRUE)) continue;
2783 cseed[jLayer].Fit();
2785 fTrackQuality[ntracks] = 1.; // dummy value
2787 if(ntracks == kMaxTracksStack) return ntracks;
2793 // Update Seeds and calculate Likelihood
2794 // fit tracklets and cook likelihood
2795 FitTiltedRieman(&cseed[0], kTRUE);
2796 for(int iLayer=0; iLayer<kNSeedPlanes; iLayer++){
2797 Int_t jLayer = planes[iLayer];
2798 cseed[jLayer].Fit(kTRUE);
2800 Double_t like = CookLikelihood(&cseed[0], planes); // to be checked
2802 if (TMath::Log(1.E-9 + like) < fkReconstructor->GetRecoParam() ->GetTrackLikelihood()){
2803 AliDebug(3, Form("Filter on likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2804 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2807 //AliInfo(Form("Passed likelihood %f[%e].", TMath::Log(1.E-9 + like), like));
2809 // book preliminary results
2810 seedQuality[ntracks] = like;
2811 fSeedLayer[ntracks] = config;/*sLayer;*/
2813 // attach clusters to the extrapolation seeds
2815 for(int iLayer=0; iLayer<kNPlanes-kNSeedPlanes; iLayer++){
2816 Int_t jLayer = planesExt[iLayer];
2817 if(!(chamber = stack[jLayer])) continue;
2819 // fit extrapolated seed
2820 if ((jLayer == 0) && !(cseed[1].IsOK())) continue;
2821 if ((jLayer == 5) && !(cseed[4].IsOK())) continue;
2822 AliTRDseedV1 pseed = cseed[jLayer];
2823 if(!pseed.AttachClusters(chamber, kTRUE)) continue;
2825 cseed[jLayer] = pseed;
2826 FitTiltedRieman(cseed, kTRUE);
2827 cseed[jLayer].Fit(kTRUE);
2831 // AliInfo("Extrapolation done.");
2832 // Debug Stream containing all the 6 tracklets
2833 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2834 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2835 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
2836 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2837 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2838 cstreamer << "MakeSeeds1"
2839 << "EventNumber=" << eventNumber
2840 << "CandidateNumber=" << candidateNumber
2841 << "S0.=" << &cseed[0]
2842 << "S1.=" << &cseed[1]
2843 << "S2.=" << &cseed[2]
2844 << "S3.=" << &cseed[3]
2845 << "S4.=" << &cseed[4]
2846 << "S5.=" << &cseed[5]
2847 << "FitterT.=" << tiltedRieman
2851 if(fkReconstructor->GetRecoParam()->HasImproveTracklets()){
2852 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
2853 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer] = cseed[jLayer];
2855 if(ImproveSeedQuality(stack, cseed) < mlayers+elayers){
2856 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2857 AliDebug(3, "Filter on improve seeds.");
2860 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) cseed[jLayer] = bseed[jLayer];
2863 //AliInfo("Improve seed quality done.");
2865 // fit full track and cook likelihoods
2866 // Double_t curv = FitRieman(&cseed[0], chi2);
2867 // Double_t chi2ZF = chi2[0] / TMath::Max((mlayers - 3.), 1.);
2868 // Double_t chi2RF = chi2[1] / TMath::Max((mlayers - 3.), 1.);
2870 // do the final track fitting (Once with vertex constraint and once without vertex constraint)
2871 Double_t chi2Vals[3];
2872 chi2Vals[0] = FitTiltedRieman(&cseed[0], kTRUE);
2873 if(fkReconstructor->GetRecoParam()->IsVertexConstrained())
2874 chi2Vals[1] = FitTiltedRiemanConstraint(&cseed[0], GetZ()); // Do Vertex Constrained fit if desired
2877 chi2Vals[2] = GetChi2Z(&cseed[0]) / TMath::Max((mlayers - 3.), 1.);
2878 // Chi2 definitions in testing stage
2879 //chi2Vals[2] = GetChi2ZTest(&cseed[0]);
2880 fTrackQuality[ntracks] = CalculateTrackLikelihood(&cseed[0], &chi2Vals[0]);
2881 //AliInfo("Hyperplane fit done\n");
2883 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
2884 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2885 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2886 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2887 TLinearFitter *fitterTC = GetTiltedRiemanFitterConstraint();
2888 TLinearFitter *fitterT = GetTiltedRiemanFitter();
2890 for(Int_t iseed = 0; iseed < kNPlanes; iseed++){
2891 ncls += cseed[iseed].IsOK() ? cseed[iseed].GetN2() : 0;
2893 cstreamer << "MakeSeeds2"
2894 << "EventNumber=" << eventNumber
2895 << "CandidateNumber=" << candidateNumber
2896 << "Chi2TR=" << chi2Vals[0]
2897 << "Chi2TC=" << chi2Vals[1]
2898 << "Nlayers=" << mlayers
2899 << "NClusters=" << ncls
2901 << "S0.=" << &cseed[0]
2902 << "S1.=" << &cseed[1]
2903 << "S2.=" << &cseed[2]
2904 << "S3.=" << &cseed[3]
2905 << "S4.=" << &cseed[4]
2906 << "S5.=" << &cseed[5]
2907 << "FitterT.=" << fitterT
2908 << "FitterTC.=" << fitterTC
2913 AliTRDtrackerDebug::SetCandidateNumber(AliTRDtrackerDebug::GetCandidateNumber() + 1);
2914 if(ntracks == kMaxTracksStack){
2915 AliWarning(Form("Number of seeds reached maximum allowed (%d) in stack.", kMaxTracksStack));
2926 //_____________________________________________________________________________
2927 AliTRDtrackV1* AliTRDtrackerV1::MakeTrack(AliTRDseedV1 * const seeds, Double_t *params)
2930 // Build a TRD track out of tracklet candidates
2933 // seeds : array of tracklets
2934 // params : array of track parameters as they are estimated by stand alone tracker. 7 elements.
2935 // [0] - radial position of the track at reference point
2936 // [1] - y position of the fit at [0]
2937 // [2] - z position of the fit at [0]
2938 // [3] - snp of the first tracklet
2939 // [4] - tgl of the first tracklet
2940 // [5] - curvature of the Riemann fit - 1/pt
2941 // [6] - sector rotation angle
2946 // Initialize the TRD track based on the parameters of the fit and a parametric covariance matrix
2947 // (diagonal with constant variance terms TODO - correct parameterization)
2949 // In case of HLT just register the tracklets in the tracker and return values of the Riemann fit. For the
2950 // offline case perform a full Kalman filter on the already found tracklets (see AliTRDtrackerV1::FollowBackProlongation()
2951 // for details). Do also MC label calculation and PID if propagation successfully.
2954 Double_t alpha = AliTRDgeometry::GetAlpha();
2955 Double_t shift = AliTRDgeometry::GetAlpha()/2.0;
2958 c[ 0] = 0.2; // s^2_y
2959 c[ 1] = 0.0; c[ 2] = 2.0; // s^2_z
2960 c[ 3] = 0.0; c[ 4] = 0.0; c[ 5] = 0.02; // s^2_snp
2961 c[ 6] = 0.0; c[ 7] = 0.0; c[ 8] = 0.0; c[ 9] = 0.1; // s^2_tgl
2962 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
2964 AliTRDtrackV1 track(seeds, ¶ms[1], c, params[0], params[6]*alpha+shift);
2965 track.PropagateTo(params[0]-5.0);
2966 AliTRDseedV1 *ptrTracklet = NULL;
2968 // skip Kalman filter for HLT
2969 if(/*fkReconstructor->IsHLT()*/kFALSE){
2970 for (Int_t jLayer = 0; jLayer < AliTRDgeometry::kNlayer; jLayer++) {
2971 track.UnsetTracklet(jLayer);
2972 ptrTracklet = &seeds[jLayer];
2973 if(!ptrTracklet->IsOK()) continue;
2974 if(TMath::Abs(ptrTracklet->GetYref(1) - ptrTracklet->GetYfit(1)) >= .2) continue; // check this condition with Marian
2975 ptrTracklet = SetTracklet(ptrTracklet);
2976 ptrTracklet->UseClusters();
2977 track.SetTracklet(ptrTracklet, fTracklets->GetEntriesFast()-1);
2979 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
2980 ptrTrack->CookPID();
2981 ptrTrack->CookLabel(.9);
2982 ptrTrack->SetReconstructor(fkReconstructor);
2986 // prevent the error message in AliTracker::MeanMaterialBudget: "start point out of geometry"
2987 if(TMath::Abs(track.GetX()) + TMath::Abs(track.GetY()) + TMath::Abs(track.GetZ()) > 10000)
2990 track.ResetCovariance(1);
2991 Int_t nc = TMath::Abs(FollowBackProlongation(track));
2992 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 5 && fkReconstructor->IsDebugStreaming()){
2993 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
2994 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
2995 Double_t p[5]; // Track Params for the Debug Stream
2996 track.GetExternalParameters(params[0], p);
2997 TTreeSRedirector &cs = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
2999 << "EventNumber=" << eventNumber
3000 << "CandidateNumber=" << candidateNumber
3002 << "X=" << params[0]
3008 << "Yin=" << params[1]
3009 << "Zin=" << params[2]
3010 << "snpin=" << params[3]
3011 << "tndin=" << params[4]
3012 << "crvin=" << params[5]
3013 << "track.=" << &track
3016 if (nc < 30) return NULL;
3018 AliTRDtrackV1 *ptrTrack = SetTrack(&track);
3019 ptrTrack->SetReconstructor(fkReconstructor);
3020 ptrTrack->CookLabel(.9);
3022 // computes PID for track
3023 ptrTrack->CookPID();
3024 // update calibration references using this track
3025 AliTRDCalibraFillHisto *calibra = AliTRDCalibraFillHisto::Instance();
3027 AliInfo("Could not get Calibra instance\n");
3028 if(calibra->GetHisto2d()) calibra->UpdateHistogramsV1(ptrTrack);
3034 //____________________________________________________________________
3035 Int_t AliTRDtrackerV1::ImproveSeedQuality(AliTRDtrackingChamber **stack, AliTRDseedV1 *cseed)
3038 // Sort tracklets according to "quality" and try to "improve" the first 4 worst
3041 // layers : Array of propagation layers for a stack/supermodule
3042 // cseed : Array of 6 seeding tracklets which has to be improved
3045 // cssed : Improved seeds
3047 // Detailed description
3049 // Iterative procedure in which new clusters are searched for each
3050 // tracklet seed such that the seed quality (see AliTRDseed::GetQuality())
3051 // can be maximized. If some optimization is found the old seeds are replaced.
3056 // make a local working copy
3057 AliTRDtrackingChamber *chamber = NULL;
3058 AliTRDseedV1 bseed[AliTRDgeometry::kNlayer];
3060 Float_t quality(0.),
3061 lQuality[] = {1.e3, 1.e3, 1.e3, 1.e3, 1.e3, 1.e3};
3063 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;){
3064 bseed[jLayer] = cseed[jLayer];
3065 if(!bseed[jLayer].IsOK()) continue;
3067 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3068 quality += lQuality[jLayer];
3070 Float_t chi2 = FitTiltedRieman(bseed, kTRUE);
3072 for (Int_t iter = 0; iter < 4; iter++) {
3073 AliDebug(2, Form("Iter[%d] Q[%f] chi2[%f]", iter, quality, chi2));
3075 // Try better cluster set
3076 Int_t nLayers(0); Float_t qualitynew(0.);
3078 TMath::Sort(Int_t(AliTRDgeometry::kNlayer), lQuality, indexes, kFALSE);
3079 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) {
3080 Int_t bLayer = indexes[jLayer];
3081 bseed[bLayer].Reset("c");
3082 if(!(chamber = stack[bLayer])) continue;
3083 if(!bseed[bLayer].AttachClusters(chamber, kTRUE)) continue;
3084 bseed[bLayer].Fit(kTRUE);
3085 if(!bseed[bLayer].IsOK()) continue;
3087 lQuality[jLayer] = bseed[jLayer].GetQuality(kTRUE);
3088 qualitynew += lQuality[jLayer];
3090 if(rLayers > nLayers){
3091 AliDebug(1, Form("Lost %d tracklets while improving.", rLayers-nLayers));
3093 } else rLayers=nLayers;
3095 if(qualitynew >= quality){
3096 AliDebug(4, Form("Quality worsen in iter[%d].", iter));
3098 } else quality = qualitynew;
3100 // try improve track parameters
3101 AliTRDseedV1 tseed[AliTRDgeometry::kNlayer];
3102 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) tseed[jLayer]=bseed[jLayer];
3103 Float_t chi2new = FitTiltedRieman(tseed, kTRUE);
3105 AliDebug(4, Form("Chi2 worsen in iter[%d].", iter));
3107 } else chi2 = chi2new;
3109 // store better tracklets
3110 for(Int_t jLayer=AliTRDgeometry::kNlayer; jLayer--;) bseed[jLayer]=tseed[jLayer];
3113 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 7 && fkReconstructor->IsDebugStreaming()){
3114 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3115 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3116 TLinearFitter *tiltedRieman = GetTiltedRiemanFitter();
3117 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3118 cstreamer << "ImproveSeedQuality"
3119 << "EventNumber=" << eventNumber
3120 << "CandidateNumber=" << candidateNumber
3121 << "Iteration=" << iter
3122 << "S0.=" << &bseed[0]
3123 << "S1.=" << &bseed[1]
3124 << "S2.=" << &bseed[2]
3125 << "S3.=" << &bseed[3]
3126 << "S4.=" << &bseed[4]
3127 << "S5.=" << &bseed[5]
3128 << "FitterT.=" << tiltedRieman
3132 // we are sure that at least 2 tracklets are OK !
3136 //_________________________________________________________________________
3137 Double_t AliTRDtrackerV1::CalculateTrackLikelihood(const AliTRDseedV1 *const tracklets, Double_t *chi2){
3139 // Calculates the Track Likelihood value. This parameter serves as main quality criterion for
3140 // the track selection
3141 // The likelihood value containes:
3142 // - The chi2 values from the both fitters and the chi2 values in z-direction from a linear fit
3143 // - The Sum of the Parameter |slope_ref - slope_fit|/Sigma of the tracklets
3144 // For all Parameters an exponential dependency is used
3146 // Parameters: - Array of tracklets (AliTRDseedV1) related to the track candidate
3147 // - Array of chi2 values:
3148 // * Non-Constrained Tilted Riemann fit
3149 // * Vertex-Constrained Tilted Riemann fit
3150 // * z-Direction from Linear fit
3151 // Output: - The calculated track likelihood
3156 Double_t chi2phi = 0, nLayers = 0;
3157 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
3158 if(!tracklets[iLayer].IsOK()) continue;
3159 chi2phi += tracklets[iLayer].GetChi2Phi();
3162 chi2phi /= Float_t (nLayers - 2.0);
3164 Double_t likeChi2Z = TMath::Exp(-chi2[2] * 0.14); // Chi2Z
3165 Double_t likeChi2TC = (fkReconstructor->GetRecoParam()->IsVertexConstrained()) ?
3166 TMath::Exp(-chi2[1] * 0.677) : 1; // Constrained Tilted Riemann
3167 Double_t likeChi2TR = TMath::Exp(-chi2[0] * 0.0078); // Non-constrained Tilted Riemann
3168 Double_t likeChi2Phi= TMath::Exp(-chi2phi * 3.23);//3.23
3169 Double_t trackLikelihood = likeChi2Z * likeChi2TR * likeChi2Phi;
3171 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3172 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3173 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3174 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3175 cstreamer << "CalculateTrackLikelihood0"
3176 << "EventNumber=" << eventNumber
3177 << "CandidateNumber=" << candidateNumber
3178 << "LikeChi2Z=" << likeChi2Z
3179 << "LikeChi2TR=" << likeChi2TR
3180 << "LikeChi2TC=" << likeChi2TC
3181 << "LikeChi2Phi=" << likeChi2Phi
3182 << "TrackLikelihood=" << trackLikelihood
3186 return trackLikelihood;
3189 //____________________________________________________________________
3190 Double_t AliTRDtrackerV1::CookLikelihood(AliTRDseedV1 *cseed, Int_t planes[4])
3193 // Calculate the probability of this track candidate.
3196 // cseeds : array of candidate tracklets
3197 // planes : array of seeding planes (see seeding configuration)
3198 // chi2 : chi2 values (on the Z and Y direction) from the rieman fit of the track.
3203 // Detailed description
3205 // The track quality is estimated based on the following 4 criteria:
3206 // 1. precision of the rieman fit on the Y direction (likea)
3207 // 2. chi2 on the Y direction (likechi2y)
3208 // 3. chi2 on the Z direction (likechi2z)
3209 // 4. number of attached clusters compared to a reference value
3210 // (see AliTRDrecoParam::fkFindable) (likeN)
3212 // The distributions for each type of probabilities are given below as of
3213 // (date). They have to be checked to assure consistency of estimation.
3216 // ratio of the total number of clusters/track which are expected to be found by the tracker.
3217 const AliTRDrecoParam *fRecoPars = fkReconstructor->GetRecoParam();
3219 Double_t chi2y = GetChi2Y(&cseed[0]);
3220 Double_t chi2z = GetChi2Z(&cseed[0]);
3222 Float_t nclusters = 0.;
3223 Double_t sumda = 0.;
3224 for(UChar_t ilayer = 0; ilayer < 4; ilayer++){
3225 Int_t jlayer = planes[ilayer];
3226 nclusters += cseed[jlayer].GetN2();
3227 sumda += TMath::Abs(cseed[jlayer].GetYfit(1) - cseed[jlayer].GetYref(1));
3231 Double_t likea = TMath::Exp(-sumda * fRecoPars->GetPhiSlope());
3232 Double_t likechi2y = 0.0000000001;
3233 if (fkReconstructor->IsCosmic() || chi2y < fRecoPars->GetChi2YCut()) likechi2y += TMath::Exp(-TMath::Sqrt(chi2y) * fRecoPars->GetChi2YSlope());
3234 Double_t likechi2z = TMath::Exp(-chi2z * fRecoPars->GetChi2ZSlope());
3235 Double_t likeN = TMath::Exp(-(fRecoPars->GetNMeanClusters() - nclusters) / fRecoPars->GetNSigmaClusters());
3236 Double_t like = likea * likechi2y * likechi2z * likeN;
3238 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) >= 2 && fkReconstructor->IsDebugStreaming()){
3239 Int_t eventNumber = AliTRDtrackerDebug::GetEventNumber();
3240 Int_t candidateNumber = AliTRDtrackerDebug::GetCandidateNumber();
3241 Int_t nTracklets = 0; Float_t meanNcls = 0;
3242 for(Int_t iseed=0; iseed < kNPlanes; iseed++){
3243 if(!cseed[iseed].IsOK()) continue;
3245 meanNcls += cseed[iseed].GetN2();
3247 if(nTracklets) meanNcls /= nTracklets;
3248 // The Debug Stream contains the seed
3249 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
3250 cstreamer << "CookLikelihood"
3251 << "EventNumber=" << eventNumber
3252 << "CandidateNumber=" << candidateNumber
3253 << "tracklet0.=" << &cseed[0]
3254 << "tracklet1.=" << &cseed[1]
3255 << "tracklet2.=" << &cseed[2]
3256 << "tracklet3.=" << &cseed[3]
3257 << "tracklet4.=" << &cseed[4]
3258 << "tracklet5.=" << &cseed[5]
3259 << "sumda=" << sumda
3260 << "chi2y=" << chi2y
3261 << "chi2z=" << chi2z
3262 << "likea=" << likea
3263 << "likechi2y=" << likechi2y
3264 << "likechi2z=" << likechi2z
3265 << "nclusters=" << nclusters
3266 << "likeN=" << likeN
3268 << "meanncls=" << meanNcls
3275 //____________________________________________________________________
3276 void AliTRDtrackerV1::GetSeedingConfig(Int_t iconfig, Int_t planes[4])
3279 // Map seeding configurations to detector planes.
3282 // iconfig : configuration index
3283 // planes : member planes of this configuration. On input empty.
3286 // planes : contains the planes which are defining the configuration
3288 // Detailed description
3290 // Here is the list of seeding planes configurations together with
3291 // their topological classification:
3309 // The topologic quality is modeled as follows:
3310 // 1. The general model is define by the equation:
3311 // p(conf) = exp(-conf/2)
3312 // 2. According to the topologic classification, configurations from the same
3313 // class are assigned the agerage value over the model values.
3314 // 3. Quality values are normalized.
3316 // The topologic quality distribution as function of configuration is given below:
3318 // <img src="gif/topologicQA.gif">
3323 case 0: // 5432 TQ 0
3329 case 1: // 4321 TQ 0
3335 case 2: // 3210 TQ 0
3341 case 3: // 5321 TQ 1
3347 case 4: // 4210 TQ 1
3353 case 5: // 5431 TQ 1
3359 case 6: // 4320 TQ 1
3365 case 7: // 5430 TQ 2
3371 case 8: // 5210 TQ 2
3377 case 9: // 5421 TQ 3
3383 case 10: // 4310 TQ 3
3389 case 11: // 5410 TQ 4
3395 case 12: // 5420 TQ 5
3401 case 13: // 5320 TQ 5
3407 case 14: // 5310 TQ 5
3416 //____________________________________________________________________
3417 void AliTRDtrackerV1::GetExtrapolationConfig(Int_t iconfig, Int_t planes[2])
3420 // Returns the extrapolation planes for a seeding configuration.
3423 // iconfig : configuration index
3424 // planes : planes which are not in this configuration. On input empty.
3427 // planes : contains the planes which are not in the configuration
3429 // Detailed description
3433 case 0: // 5432 TQ 0
3437 case 1: // 4321 TQ 0
3441 case 2: // 3210 TQ 0
3445 case 3: // 5321 TQ 1
3449 case 4: // 4210 TQ 1
3453 case 5: // 5431 TQ 1
3457 case 6: // 4320 TQ 1
3461 case 7: // 5430 TQ 2
3465 case 8: // 5210 TQ 2
3469 case 9: // 5421 TQ 3
3473 case 10: // 4310 TQ 3
3477 case 11: // 5410 TQ 4
3481 case 12: // 5420 TQ 5
3485 case 13: // 5320 TQ 5
3489 case 14: // 5310 TQ 5
3496 //____________________________________________________________________
3497 AliCluster* AliTRDtrackerV1::GetCluster(Int_t idx) const
3499 if(!fClusters) return NULL;
3500 Int_t ncls = fClusters->GetEntriesFast();
3501 return idx >= 0 && idx < ncls ? (AliCluster*)fClusters->UncheckedAt(idx) : NULL;
3504 //____________________________________________________________________
3505 AliTRDseedV1* AliTRDtrackerV1::GetTracklet(Int_t idx) const
3507 if(!fTracklets) return NULL;
3508 Int_t ntrklt = fTracklets->GetEntriesFast();
3509 return idx >= 0 && idx < ntrklt ? (AliTRDseedV1*)fTracklets->UncheckedAt(idx) : NULL;
3512 //____________________________________________________________________
3513 AliKalmanTrack* AliTRDtrackerV1::GetTrack(Int_t idx) const
3515 if(!fTracks) return NULL;
3516 Int_t ntrk = fTracks->GetEntriesFast();
3517 return idx >= 0 && idx < ntrk ? (AliKalmanTrack*)fTracks->UncheckedAt(idx) : NULL;
3522 // //_____________________________________________________________________________
3523 // Int_t AliTRDtrackerV1::Freq(Int_t n, const Int_t *inlist
3524 // , Int_t *outlist, Bool_t down)
3527 // // Sort eleements according occurancy
3528 // // The size of output array has is 2*n
3535 // Int_t *sindexS = new Int_t[n]; // Temporary array for sorting
3536 // Int_t *sindexF = new Int_t[2*n];
3537 // for (Int_t i = 0; i < n; i++) {
3541 // TMath::Sort(n,inlist,sindexS,down);
3543 // Int_t last = inlist[sindexS[0]];
3544 // Int_t val = last;
3546 // sindexF[0+n] = last;
3547 // Int_t countPos = 0;
3549 // // Find frequency
3550 // for (Int_t i = 1; i < n; i++) {
3551 // val = inlist[sindexS[i]];
3552 // if (last == val) {
3553 // sindexF[countPos]++;
3557 // sindexF[countPos+n] = val;
3558 // sindexF[countPos]++;
3562 // if (last == val) {
3566 // // Sort according frequency
3567 // TMath::Sort(countPos,sindexF,sindexS,kTRUE);
3569 // for (Int_t i = 0; i < countPos; i++) {
3570 // outlist[2*i ] = sindexF[sindexS[i]+n];
3571 // outlist[2*i+1] = sindexF[sindexS[i]];
3574 // delete [] sindexS;
3575 // delete [] sindexF;
3582 //____________________________________________________________________
3583 void AliTRDtrackerV1::ResetSeedTB()
3585 // reset buffer for seeding time bin layers. If the time bin
3586 // layers are not allocated this function allocates them
3588 for(Int_t isl=0; isl<kNSeedPlanes; isl++){
3589 if(!fSeedTB[isl]) fSeedTB[isl] = new AliTRDchamberTimeBin();
3590 else fSeedTB[isl]->Clear();
3595 //_____________________________________________________________________________
3596 Float_t AliTRDtrackerV1::GetChi2Y(const AliTRDseedV1 * const tracklets) const
3598 // Calculates normalized chi2 in y-direction
3599 // chi2 = Sum chi2 / n_tracklets
3601 Double_t chi2 = 0.; Int_t n = 0;
3602 for(Int_t ipl = kNPlanes; ipl--;){
3603 if(!tracklets[ipl].IsOK()) continue;
3604 chi2 += tracklets[ipl].GetChi2Y();
3607 return n ? chi2/n : 0.;
3610 //_____________________________________________________________________________
3611 Float_t AliTRDtrackerV1::GetChi2Z(const AliTRDseedV1 *const tracklets) const
3613 // Calculates normalized chi2 in z-direction
3614 // chi2 = Sum chi2 / n_tracklets
3616 Double_t chi2 = 0; Int_t n = 0;
3617 for(Int_t ipl = kNPlanes; ipl--;){
3618 if(!tracklets[ipl].IsOK()) continue;
3619 chi2 += tracklets[ipl].GetChi2Z();
3622 return n ? chi2/n : 0.;
3625 //____________________________________________________________________
3626 Float_t AliTRDtrackerV1::CalculateReferenceX(const AliTRDseedV1 *const tracklets){
3628 // Calculates the reference x-position for the tilted Rieman fit defined as middle
3629 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
3630 // are taken into account
3632 // Parameters: - Array of tracklets(AliTRDseedV1)
3634 // Output: - The reference x-position(Float_t)
3635 // Only kept for compatibility with the old code
3637 Int_t nDistances = 0;
3638 Float_t meanDistance = 0.;
3639 Int_t startIndex = 5;
3640 for(Int_t il =5; il > 0; il--){
3641 if(tracklets[il].IsOK() && tracklets[il -1].IsOK()){
3642 Float_t xdiff = tracklets[il].GetX0() - tracklets[il -1].GetX0();
3643 meanDistance += xdiff;
3646 if(tracklets[il].IsOK()) startIndex = il;
3648 if(tracklets[0].IsOK()) startIndex = 0;
3650 // We should normally never get here
3651 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
3652 Int_t iok = 0, idiff = 0;
3653 // This attempt is worse and should be avoided:
3654 // check for two chambers which are OK and repeat this without taking the mean value
3655 // Strategy avoids a division by 0;
3656 for(Int_t il = 5; il >= 0; il--){
3657 if(tracklets[il].IsOK()){
3658 xpos[iok] = tracklets[il].GetX0();
3662 if(iok) idiff++; // to get the right difference;
3666 meanDistance = (xpos[0] - xpos[1])/idiff;
3669 // we have do not even have 2 layers which are OK? The we do not need to fit at all
3674 meanDistance /= nDistances;
3676 return tracklets[startIndex].GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
3679 //_____________________________________________________________________________
3680 Double_t AliTRDtrackerV1::FitTiltedRiemanV1(AliTRDseedV1 *const tracklets){
3682 // Track Fitter Function using the new class implementation of
3685 AliTRDtrackFitterRieman fitter;
3686 fitter.SetRiemanFitter(GetTiltedRiemanFitter());
3688 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) fitter.SetTracklet(il, &tracklets[il]);
3689 Double_t chi2 = fitter.Eval();
3690 // Update the tracklets
3691 Double_t cov[15]; Double_t x0;
3692 memset(cov, 0, sizeof(Double_t) * 15);
3693 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++){
3694 x0 = tracklets[il].GetX0();
3695 tracklets[il].SetYref(0, fitter.GetYat(x0));
3696 tracklets[il].SetZref(0, fitter.GetZat(x0));
3697 tracklets[il].SetYref(1, fitter.GetDyDxAt(x0));
3698 tracklets[il].SetZref(1, fitter.GetDzDx());
3699 tracklets[il].SetC(fitter.GetCurvature());
3700 fitter.GetCovAt(x0, cov);
3701 tracklets[il].SetCovRef(cov);
3702 tracklets[il].SetChi2(chi2);
3707 ///////////////////////////////////////////////////////
3709 // Resources of class AliTRDLeastSquare //
3711 ///////////////////////////////////////////////////////
3713 //_____________________________________________________________________________
3714 AliTRDtrackerV1::AliTRDLeastSquare::AliTRDLeastSquare(){
3716 // Constructor of the nested class AliTRDtrackFitterLeastSquare
3718 // Fast solving linear regresion in 2D
3720 // The data members have the following meaning
3731 // fCovarianceMatrix[0] : s2a
3732 // fCovarianceMatrix[1] : s2b
3733 // fCovarianceMatrix[2] : cov(ab)
3735 memset(fParams, 0, sizeof(Double_t) * 2);
3736 memset(fSums, 0, sizeof(Double_t) * 6);
3737 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3741 //_____________________________________________________________________________
3742 void AliTRDtrackerV1::AliTRDLeastSquare::AddPoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3744 // Adding Point to the fitter
3747 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3749 const Double_t &xpt = *x;
3750 // printf("Adding point x = %f, y = %f, sigma = %f\n", xpt, y, sigmaY);
3752 fSums[1] += weight * xpt;
3753 fSums[2] += weight * y;
3754 fSums[3] += weight * xpt * y;
3755 fSums[4] += weight * xpt * xpt;
3756 fSums[5] += weight * y * y;
3759 //_____________________________________________________________________________
3760 void AliTRDtrackerV1::AliTRDLeastSquare::RemovePoint(const Double_t *const x, Double_t y, Double_t sigmaY){
3762 // Remove Point from the sample
3765 Double_t weight = 1/(sigmaY > 1e-9 ? sigmaY : 1e-9);
3767 const Double_t &xpt = *x;
3769 fSums[1] -= weight * xpt;
3770 fSums[2] -= weight * y;
3771 fSums[3] -= weight * xpt * y;
3772 fSums[4] -= weight * xpt * xpt;
3773 fSums[5] -= weight * y * y;
3776 //_____________________________________________________________________________
3777 Bool_t AliTRDtrackerV1::AliTRDLeastSquare::Eval(){
3779 // Evaluation of the fit:
3780 // Calculation of the parameters
3781 // Calculation of the covariance matrix
3784 Double_t det = fSums[0] * fSums[4] - fSums[1] *fSums[1];
3785 if(det==0) return kFALSE;
3787 // for(Int_t isum = 0; isum < 5; isum++)
3788 // printf("fSums[%d] = %f\n", isum, fSums[isum]);
3789 // printf("denominator = %f\n", denominator);
3790 fParams[0] = (fSums[2] * fSums[4] - fSums[1] * fSums[3])/det;
3791 fParams[1] = (fSums[0] * fSums[3] - fSums[1] * fSums[2])/det;
3792 // printf("fParams[0] = %f, fParams[1] = %f\n", fParams[0], fParams[1]);
3794 // Covariance matrix
3795 Double_t den = fSums[0]*fSums[4] - fSums[1]*fSums[1];
3796 fCovarianceMatrix[0] = fSums[4] / den;
3797 fCovarianceMatrix[1] = fSums[0] / den;
3798 fCovarianceMatrix[2] = -fSums[1] / den;
3799 /* fCovarianceMatrix[0] = fSums[4] / fSums[0] - fSums[1] * fSums[1] / (fSums[0] * fSums[0]);
3800 fCovarianceMatrix[1] = fSums[5] / fSums[0] - fSums[2] * fSums[2] / (fSums[0] * fSums[0]);
3801 fCovarianceMatrix[2] = fSums[3] / fSums[0] - fSums[1] * fSums[2] / (fSums[0] * fSums[0]);*/
3808 //_____________________________________________________________________________
3809 Double_t AliTRDtrackerV1::AliTRDLeastSquare::GetFunctionValue(const Double_t *const xpos) const {
3811 // Returns the Function value of the fitted function at a given x-position
3813 return fParams[0] + fParams[1] * (*xpos);
3816 //_____________________________________________________________________________
3817 void AliTRDtrackerV1::AliTRDLeastSquare::GetCovarianceMatrix(Double_t *storage) const {
3819 // Copies the values of the covariance matrix into the storage
3821 memcpy(storage, fCovarianceMatrix, sizeof(Double_t) * 3);
3824 //_____________________________________________________________________________
3825 void AliTRDtrackerV1::AliTRDLeastSquare::Reset(){
3829 memset(fParams, 0, sizeof(Double_t) * 2);
3830 memset(fCovarianceMatrix, 0, sizeof(Double_t) * 3);
3831 memset(fSums, 0, sizeof(Double_t) * 6);
3834 ///////////////////////////////////////////////////////
3836 // Resources of class AliTRDtrackFitterRieman //
3838 ///////////////////////////////////////////////////////
3840 //_____________________________________________________________________________
3841 AliTRDtrackerV1::AliTRDtrackFitterRieman::AliTRDtrackFitterRieman():
3847 fSysClusterError(0.)
3850 // Default constructor
3852 fZfitter = new AliTRDLeastSquare;
3853 fCovarPolY = new TMatrixD(3,3);
3854 fCovarPolZ = new TMatrixD(2,2);
3855 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * 6);
3856 memset(fParameters, 0, sizeof(Double_t) * 5);
3857 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3858 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3861 //_____________________________________________________________________________
3862 AliTRDtrackerV1::AliTRDtrackFitterRieman::~AliTRDtrackFitterRieman(){
3866 if(fZfitter) delete fZfitter;
3867 if(fCovarPolY) delete fCovarPolY;
3868 if(fCovarPolZ) delete fCovarPolZ;
3871 //_____________________________________________________________________________
3872 void AliTRDtrackerV1::AliTRDtrackFitterRieman::Reset(){
3877 fTrackFitter->StoreData(kTRUE);
3878 fTrackFitter->ClearPoints();
3884 memset(fTracklets, 0, sizeof(AliTRDseedV1 *) * AliTRDgeometry::kNlayer);
3885 memset(fParameters, 0, sizeof(Double_t) * 5);
3886 memset(fSumPolY, 0, sizeof(Double_t) * 5);
3887 memset(fSumPolZ, 0, sizeof(Double_t) * 2);
3888 for(Int_t irow = 0; irow < fCovarPolY->GetNrows(); irow++)
3889 for(Int_t icol = 0; icol < fCovarPolY->GetNcols(); icol++){
3890 (*fCovarPolY)(irow, icol) = 0.;
3891 if(irow < 2 && icol < 2)
3892 (*fCovarPolZ)(irow, icol) = 0.;
3896 //_____________________________________________________________________________
3897 void AliTRDtrackerV1::AliTRDtrackFitterRieman::SetTracklet(Int_t itr, AliTRDseedV1 *tracklet){
3899 // Add tracklet into the fitter
3901 if(itr >= AliTRDgeometry::kNlayer) return;
3902 fTracklets[itr] = tracklet;
3905 //_____________________________________________________________________________
3906 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::Eval(){
3909 // 1. Apply linear transformation and store points in the fitter
3910 // 2. Evaluate the fit
3911 // 3. Check if the result of the fit in z-direction is reasonable
3913 // 3a. Fix the parameters 3 and 4 with the results of a simple least
3915 // 3b. Redo the fit with the fixed parameters
3916 // 4. Store fit results (parameters and errors)
3921 fXref = CalculateReferenceX();
3922 for(Int_t il = 0; il < AliTRDgeometry::kNlayer; il++) UpdateFitters(fTracklets[il]);
3923 if(!fTrackFitter->GetNpoints()) return 1e10;
3925 fTrackFitter->Eval();
3927 fParameters[3] = fTrackFitter->GetParameter(3);
3928 fParameters[4] = fTrackFitter->GetParameter(4);
3929 if(!CheckAcceptable(fParameters[3], fParameters[4])) {
3930 fTrackFitter->FixParameter(3, fZfitter->GetFunctionValue(&fXref));
3931 fTrackFitter->FixParameter(4, fZfitter->GetFunctionParameter(1));
3932 fTrackFitter->Eval();
3933 fTrackFitter->ReleaseParameter(3);
3934 fTrackFitter->ReleaseParameter(4);
3935 fParameters[3] = fTrackFitter->GetParameter(3);
3936 fParameters[4] = fTrackFitter->GetParameter(4);
3938 // Update the Fit Parameters and the errors
3939 fParameters[0] = fTrackFitter->GetParameter(0);
3940 fParameters[1] = fTrackFitter->GetParameter(1);
3941 fParameters[2] = fTrackFitter->GetParameter(2);
3943 // Prepare Covariance estimation
3944 (*fCovarPolY)(0,0) = fSumPolY[0]; (*fCovarPolY)(1,1) = fSumPolY[2]; (*fCovarPolY)(2,2) = fSumPolY[4];
3945 (*fCovarPolY)(1,0) = (*fCovarPolY)(0,1) = fSumPolY[1];
3946 (*fCovarPolY)(2,0) = (*fCovarPolY)(0,2) = fSumPolY[2];
3947 (*fCovarPolY)(2,1) = (*fCovarPolY)(1,2) = fSumPolY[3];
3948 fCovarPolY->Invert();
3949 (*fCovarPolZ)(0,0) = fSumPolZ[0]; (*fCovarPolZ)(1,1) = fSumPolZ[2];
3950 (*fCovarPolZ)(1,0) = (*fCovarPolZ)(0,1) = fSumPolZ[1];
3951 fCovarPolZ->Invert();
3952 return fTrackFitter->GetChisquare() / fTrackFitter->GetNpoints();
3955 //_____________________________________________________________________________
3956 void AliTRDtrackerV1::AliTRDtrackFitterRieman::UpdateFitters(AliTRDseedV1 * const tracklet){
3958 // Does the transformations and updates the fitters
3959 // The following transformation is applied
3961 AliTRDcluster *cl = NULL;
3962 Double_t x, y, z, dx, t, w, we, yerr, zerr;
3964 if(!tracklet || !tracklet->IsOK()) return;
3965 Double_t tilt = tracklet->GetTilt();
3966 for(Int_t itb = 0; itb < AliTRDseedV1::kNclusters; itb++){
3967 if(!(cl = tracklet->GetClusters(itb))) continue;
3968 if(!cl->IsInChamber()) continue;
3969 if (!tracklet->IsUsable(itb)) continue;
3976 uvt[0] = 2. * x * t;
3978 uvt[2] = 2. * tilt * t;
3979 uvt[3] = 2. * tilt * dx * t;
3980 w = 2. * (y + tilt*z) * t;
3981 // error definition changes for the different calls
3983 we *= TMath::Sqrt(cl->GetSigmaY2()+tilt*tilt*cl->GetSigmaZ2());
3984 // Update sums for error calculation
3985 yerr = 1./(TMath::Sqrt(cl->GetSigmaY2()) + fSysClusterError);
3987 zerr = 1./cl->GetSigmaZ2();
3988 for(Int_t ipol = 0; ipol < 5; ipol++){
3989 fSumPolY[ipol] += yerr;
3992 fSumPolZ[ipol] += zerr;
3996 fTrackFitter->AddPoint(uvt, w, we);
3997 fZfitter->AddPoint(&x, z, static_cast<Double_t>(TMath::Sqrt(cl->GetSigmaZ2())));
4001 //_____________________________________________________________________________
4002 Bool_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CheckAcceptable(Double_t offset, Double_t slope){
4004 // Check whether z-results are acceptable
4005 // Definition: Distance between tracklet fit and track fit has to be
4006 // less then half a padlength
4007 // Point of comparision is at the anode wire
4009 Bool_t acceptablez = kTRUE;
4010 Double_t zref = 0.0;
4011 for (Int_t iLayer = 0; iLayer < kNPlanes; iLayer++) {
4012 if(!fTracklets[iLayer]->IsOK()) continue;
4013 zref = offset + slope * (fTracklets[iLayer]->GetX0() - fXref);
4014 if (TMath::Abs(fTracklets[iLayer]->GetZfit(0) - zref) > fTracklets[iLayer]->GetPadLength() * 0.5 + 1.0)
4015 acceptablez = kFALSE;
4020 //_____________________________________________________________________________
4021 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetYat(Double_t x) const {
4023 // Calculate y position out of the track parameters
4024 // y: R^2 = (x - x0)^2 + (y - y0)^2
4025 // => y = y0 +/- Sqrt(R^2 - (x - x0)^2)
4026 // R = Sqrt() = 1/Curvature
4027 // => y = y0 +/- Sqrt(1/Curvature^2 - (x - x0)^2)
4030 Double_t disc = (x * fParameters[0] + fParameters[1]);
4031 disc = 1 - fParameters[0]*fParameters[2] + fParameters[1]*fParameters[1] - disc*disc;
4033 disc = TMath::Sqrt(disc);
4034 y = (1.0 - disc) / fParameters[0];
4039 //_____________________________________________________________________________
4040 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetZat(Double_t x) const {
4042 // Return z position for a given x position
4043 // Simple linear function
4045 return fParameters[3] + fParameters[4] * (x - fXref);
4048 //_____________________________________________________________________________
4049 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetDyDxAt(Double_t x) const {
4051 // Calculate dydx at a given radial position out of the track parameters
4052 // dy: R^2 = (x - x0)^2 + (y - y0)^2
4053 // => y = +/- Sqrt(R^2 - (x - x0)^2) + y0
4054 // => dy/dx = (x - x0)/Sqrt(R^2 - (x - x0)^2)
4055 // Curvature: cr = 1/R = a/Sqrt(1 + b^2 - c*a)
4056 // => dy/dx = (x - x0)/(1/(cr^2) - (x - x0)^2)
4058 Double_t x0 = -fParameters[1] / fParameters[0];
4059 Double_t curvature = GetCurvature();
4061 if (-fParameters[2] * fParameters[0] + fParameters[1] * fParameters[1] + 1 > 0) {
4062 if (1.0/(curvature * curvature) - (x - x0) * (x - x0) > 0.0) {
4063 Double_t yderiv = (x - x0) / TMath::Sqrt(1.0/(curvature * curvature) - (x - x0) * (x - x0));
4064 if (fParameters[0] < 0) yderiv *= -1.0;
4071 //_____________________________________________________________________________
4072 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCurvature() const {
4074 // Calculate track curvature
4077 Double_t curvature = 1.0 + fParameters[1]*fParameters[1] - fParameters[2]*fParameters[0];
4078 if (curvature > 0.0)
4079 curvature = fParameters[0] / TMath::Sqrt(curvature);
4083 //_____________________________________________________________________________
4084 void AliTRDtrackerV1::AliTRDtrackFitterRieman::GetCovAt(Double_t x, Double_t *cov) const {
4086 // Error Definition according to gauss error propagation
4088 TMatrixD transform(3,3);
4089 transform(0,0) = transform(1,1) = transform(2,2) = 1;
4090 transform(0,1) = transform(1,2) = x;
4091 transform(0,2) = x*x;
4092 TMatrixD covariance(transform, TMatrixD::kMult, *fCovarPolY);
4093 covariance *= transform.T();
4094 cov[0] = covariance(0,0);
4095 TMatrixD transformZ(2,2);
4096 transformZ(0,0) = transformZ(1,1) = 1;
4097 transformZ(0,1) = x;
4098 TMatrixD covarZ(transformZ, TMatrixD::kMult, *fCovarPolZ);
4099 covarZ *= transformZ.T();
4100 cov[1] = covarZ(0,0);
4104 //____________________________________________________________________
4105 Double_t AliTRDtrackerV1::AliTRDtrackFitterRieman::CalculateReferenceX(){
4107 // Calculates the reference x-position for the tilted Rieman fit defined as middle
4108 // of the stack (middle between layers 2 and 3). For the calculation all the tracklets
4109 // are taken into account
4111 // Parameters: - Array of tracklets(AliTRDseedV1)
4113 // Output: - The reference x-position(Float_t)
4115 Int_t nDistances = 0;
4116 Float_t meanDistance = 0.;
4117 Int_t startIndex = 5;
4118 for(Int_t il =5; il > 0; il--){
4119 if(fTracklets[il]->IsOK() && fTracklets[il -1]->IsOK()){
4120 Float_t xdiff = fTracklets[il]->GetX0() - fTracklets[il -1]->GetX0();
4121 meanDistance += xdiff;
4124 if(fTracklets[il]->IsOK()) startIndex = il;
4126 if(fTracklets[0]->IsOK()) startIndex = 0;
4128 // We should normally never get here
4129 Float_t xpos[2]; memset(xpos, 0, sizeof(Float_t) * 2);
4130 Int_t iok = 0, idiff = 0;
4131 // This attempt is worse and should be avoided:
4132 // check for two chambers which are OK and repeat this without taking the mean value
4133 // Strategy avoids a division by 0;
4134 for(Int_t il = 5; il >= 0; il--){
4135 if(fTracklets[il]->IsOK()){
4136 xpos[iok] = fTracklets[il]->GetX0();
4140 if(iok) idiff++; // to get the right difference;
4144 meanDistance = (xpos[0] - xpos[1])/idiff;
4147 // we have do not even have 2 layers which are OK? The we do not need to fit at all
4152 meanDistance /= nDistances;
4154 return fTracklets[startIndex]->GetX0() + (2.5 - startIndex) * meanDistance - 0.5 * (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());