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1 | /************************************************************************** | |
2 | * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * | |
3 | * * | |
4 | * Author: The ALICE Off-line Project. * | |
5 | * Contributors are mentioned in the code where appropriate. * | |
6 | * * | |
7 | * Permission to use, copy, modify and distribute this software and its * | |
8 | * documentation strictly for non-commercial purposes is hereby granted * | |
9 | * without fee, provided that the above copyright notice appears in all * | |
10 | * copies and that both the copyright notice and this permission notice * | |
11 | * appear in the supporting documentation. The authors make no claims * | |
12 | * about the suitability of this software for any purpose. It is * | |
13 | * provided "as is" without express or implied warranty. * | |
14 | **************************************************************************/ | |
15 | ||
16 | /* $Id$ */ | |
17 | ||
18 | //----------------------------------------------------------------------------- | |
19 | /// \class AliMUONTrackReconstructor | |
20 | /// MUON track reconstructor using the original method | |
21 | /// | |
22 | /// This class contains as data: | |
23 | /// - the parameters for the track reconstruction | |
24 | /// | |
25 | /// It contains as methods, among others: | |
26 | /// - MakeTracks to build the tracks | |
27 | //----------------------------------------------------------------------------- | |
28 | ||
29 | #include "AliMUONTrackReconstructor.h" | |
30 | ||
31 | #include "AliMUONConstants.h" | |
32 | #include "AliMUONVCluster.h" | |
33 | #include "AliMUONVClusterServer.h" | |
34 | #include "AliMUONVClusterStore.h" | |
35 | #include "AliMUONTrack.h" | |
36 | #include "AliMUONTrackParam.h" | |
37 | #include "AliMUONTrackExtrap.h" | |
38 | #include "AliMUONRecoParam.h" | |
39 | #include "AliMUONGeometryTransformer.h" | |
40 | ||
41 | #include "AliMpArea.h" | |
42 | ||
43 | #include "AliLog.h" | |
44 | ||
45 | #include <TMinuit.h> | |
46 | #include <Riostream.h> | |
47 | #include <TMath.h> | |
48 | #include <TMatrixD.h> | |
49 | #include <TClonesArray.h> | |
50 | ||
51 | // Functions to be minimized with Minuit | |
52 | void TrackChi2(Int_t &nParam, Double_t *gradient, Double_t &chi2, Double_t *param, Int_t flag); | |
53 | ||
54 | using std::endl; | |
55 | using std::cout; | |
56 | /// \cond CLASSIMP | |
57 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context | |
58 | /// \endcond | |
59 | ||
60 | //__________________________________________________________________________ | |
61 | AliMUONTrackReconstructor::AliMUONTrackReconstructor(const AliMUONRecoParam* recoParam, AliMUONVClusterServer* clusterServer, | |
62 | const AliMUONGeometryTransformer* transformer) | |
63 | : AliMUONVTrackReconstructor(recoParam, clusterServer, transformer) | |
64 | { | |
65 | /// Constructor | |
66 | } | |
67 | ||
68 | //__________________________________________________________________________ | |
69 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor() | |
70 | { | |
71 | /// Destructor | |
72 | } | |
73 | ||
74 | //__________________________________________________________________________ | |
75 | Bool_t AliMUONTrackReconstructor::MakeTrackCandidates(AliMUONVClusterStore& clusterStore) | |
76 | { | |
77 | /// To make track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
78 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. | |
79 | /// Good candidates are made of at least three clusters. | |
80 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
81 | ||
82 | TClonesArray *segments; | |
83 | AliMUONTrack *track; | |
84 | Int_t iCandidate = 0; | |
85 | Bool_t clusterFound; | |
86 | ||
87 | AliDebug(1,"Enter MakeTrackCandidates"); | |
88 | ||
89 | // Unless we're doing combined tracking, we'll clusterize all stations at once | |
90 | Int_t firstChamber(0); | |
91 | Int_t lastChamber(9); | |
92 | ||
93 | if (GetRecoParam()->CombineClusterTrackReco()) { | |
94 | // ... Here's the exception : ask the clustering to reconstruct | |
95 | // clusters *only* in station 4 and 5 for combined tracking | |
96 | firstChamber = 6; | |
97 | } | |
98 | ||
99 | for (Int_t i = firstChamber; i <= lastChamber; ++i ) | |
100 | { | |
101 | if (fClusterServer && GetRecoParam()->UseChamber(i)) fClusterServer->Clusterize(i, clusterStore, AliMpArea(), GetRecoParam()); | |
102 | } | |
103 | ||
104 | // Loop over stations(1..) 5 and 4 and make track candidates | |
105 | for (Int_t istat=4; istat>=3; istat--) { | |
106 | ||
107 | // Make segments in the station | |
108 | segments = MakeSegmentsBetweenChambers(clusterStore, 2*istat, 2*istat+1); | |
109 | ||
110 | // Loop over segments | |
111 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) | |
112 | { | |
113 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
114 | ||
115 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
116 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg]),GetRecoParam()->GetBendingVertexDispersion()); | |
117 | fNRecTracks++; | |
118 | ||
119 | // Look for compatible cluster(s) in the other station | |
120 | if (GetRecoParam()->MakeTrackCandidatesFast()) | |
121 | clusterFound = FollowLinearTrackInStation(*track, clusterStore, 7-istat); | |
122 | else clusterFound = FollowTrackInStation(*track, clusterStore, 7-istat); | |
123 | ||
124 | // Remove track if no cluster found on a requested station | |
125 | // or abort tracking if there are too many candidates | |
126 | if (GetRecoParam()->RequestStation(7-istat)) { | |
127 | if (!clusterFound) { | |
128 | fRecTracksPtr->Remove(track); | |
129 | fNRecTracks--; | |
130 | } else if (fNRecTracks > GetRecoParam()->GetMaxTrackCandidates()) { | |
131 | AliError(Form("Too many track candidates (%d tracks). Stop tracking.", fNRecTracks)); | |
132 | return kFALSE; | |
133 | } | |
134 | } else { | |
135 | if ((fNRecTracks + segments->GetEntriesFast() - iseg - 1) > GetRecoParam()->GetMaxTrackCandidates()) { | |
136 | AliError(Form("Too many track candidates (%d tracks). Stop tracking.", fNRecTracks + segments->GetEntriesFast() - iseg - 1)); | |
137 | return kFALSE; | |
138 | } | |
139 | } | |
140 | ||
141 | } | |
142 | ||
143 | } | |
144 | ||
145 | // Keep all different tracks or only the best ones as required | |
146 | if (GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); | |
147 | else RemoveDoubleTracks(); | |
148 | ||
149 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
150 | ||
151 | return kTRUE; | |
152 | ||
153 | } | |
154 | ||
155 | //__________________________________________________________________________ | |
156 | Bool_t AliMUONTrackReconstructor::MakeMoreTrackCandidates(AliMUONVClusterStore& clusterStore) | |
157 | { | |
158 | /// To make extra track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
159 | /// clustering is supposed to be already done | |
160 | /// Start with segments made of 1 cluster in each of the stations 4 and 5 then follow track in remaining chambers. | |
161 | /// Good candidates are made of at least three clusters if both station are requested (two otherwise). | |
162 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
163 | ||
164 | TClonesArray *segments; | |
165 | AliMUONObjectPair *segment; | |
166 | AliMUONTrack *track; | |
167 | Int_t iCandidate = 0, iCurrentTrack, nCurrentTracks; | |
168 | Bool_t clusterFound; | |
169 | ||
170 | AliDebug(1,"Enter MakeMoreTrackCandidates"); | |
171 | ||
172 | // Double loop over chambers in stations(1..) 4 and 5 to make track candidates | |
173 | for (Int_t ich1 = 6; ich1 <= 7; ich1++) { | |
174 | for (Int_t ich2 = 8; ich2 <= 9; ich2++) { | |
175 | ||
176 | // Make segments in the station | |
177 | segments = MakeSegmentsBetweenChambers(clusterStore, ich1, ich2); | |
178 | ||
179 | /// Remove segments already attached to a track | |
180 | RemoveUsedSegments(*segments); | |
181 | ||
182 | // Loop over segments | |
183 | for (Int_t iSegment=0; iSegment<segments->GetEntriesFast(); iSegment++) | |
184 | { | |
185 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
186 | segment = (AliMUONObjectPair*) segments->UncheckedAt(iSegment); | |
187 | ||
188 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
189 | iCurrentTrack = fRecTracksPtr->GetLast()+1; | |
190 | track = new ((*fRecTracksPtr)[iCurrentTrack]) AliMUONTrack(segment,GetRecoParam()->GetBendingVertexDispersion()); | |
191 | fNRecTracks++; | |
192 | ||
193 | // Look for compatible cluster(s) in the second chamber of station 5 | |
194 | clusterFound = FollowLinearTrackInChamber(*track, clusterStore, 17-ich2); | |
195 | ||
196 | // skip the original track in case it has been removed | |
197 | if (GetRecoParam()->TrackAllTracks() && clusterFound) iCurrentTrack++; | |
198 | ||
199 | // loop over every new tracks | |
200 | nCurrentTracks = fRecTracksPtr->GetLast()+1; | |
201 | while (iCurrentTrack < nCurrentTracks) { | |
202 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iCurrentTrack); | |
203 | ||
204 | // Look for compatible cluster(s) in the second chamber of station 4 | |
205 | FollowLinearTrackInChamber(*track, clusterStore, 13-ich1); | |
206 | ||
207 | iCurrentTrack++; | |
208 | } | |
209 | ||
210 | // abort tracking if there are too many candidates | |
211 | if ((fNRecTracks + segments->GetEntriesFast() - iSegment - 1) > GetRecoParam()->GetMaxTrackCandidates()) { | |
212 | AliError(Form("Too many track candidates (%d tracks). Stop tracking.", fNRecTracks + segments->GetEntriesFast() - iSegment - 1)); | |
213 | return kFALSE; | |
214 | } | |
215 | ||
216 | } | |
217 | ||
218 | } | |
219 | } | |
220 | ||
221 | // Keep only the best tracks if required | |
222 | if (!GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); | |
223 | else fRecTracksPtr->Compress(); | |
224 | ||
225 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
226 | ||
227 | return kTRUE; | |
228 | ||
229 | } | |
230 | ||
231 | //__________________________________________________________________________ | |
232 | Bool_t AliMUONTrackReconstructor::FollowTracks(AliMUONVClusterStore& clusterStore) | |
233 | { | |
234 | /// Follow tracks in stations(1..) 3, 2 and 1 | |
235 | AliDebug(1,"Enter FollowTracks"); | |
236 | ||
237 | AliMUONTrack *track, *nextTrack; | |
238 | AliMUONTrackParam *trackParam, *nextTrackParam; | |
239 | Int_t currentNRecTracks; | |
240 | ||
241 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * | |
242 | GetRecoParam()->GetSigmaCutForTracking(); | |
243 | ||
244 | for (Int_t station = 2; station >= 0; station--) { | |
245 | ||
246 | // Save the actual number of reconstructed track in case of | |
247 | // tracks are added or suppressed during the tracking procedure | |
248 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
249 | currentNRecTracks = fNRecTracks; | |
250 | ||
251 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { | |
252 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); | |
253 | ||
254 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
255 | ||
256 | // Fit the track: | |
257 | // Do not take into account the multiple scattering to speed up the fit | |
258 | // Calculate the track parameter covariance matrix | |
259 | // If there is no cluster out of station 4 or 5 then use the vertex to better constrain the fit | |
260 | if (((AliMUONTrackParam*) track->GetTrackParamAtCluster()->First())->GetClusterPtr()->GetChamberId() > 5) | |
261 | Fit(*track, kFALSE, kTRUE, kTRUE); | |
262 | else Fit(*track, kFALSE, kFALSE, kTRUE); | |
263 | ||
264 | // remove tracks out of limits | |
265 | if (!IsAcceptable(*((AliMUONTrackParam*)track->GetTrackParamAtCluster()->First()))) { | |
266 | fRecTracksPtr->Remove(track); | |
267 | fNRecTracks--; | |
268 | continue; | |
269 | } | |
270 | ||
271 | // remove track if the normalized chi2 is too high | |
272 | if (track->GetNormalizedChi2() > sigmaCut2) { | |
273 | fRecTracksPtr->Remove(track); | |
274 | fNRecTracks--; | |
275 | continue; | |
276 | } | |
277 | ||
278 | // save parameters from fit into smoothed parameters to complete track afterward | |
279 | if (GetRecoParam()->ComplementTracks()) { | |
280 | ||
281 | if (station==2) { // save track parameters on stations 4 and 5 | |
282 | ||
283 | // extrapolate track parameters and covariances at each cluster | |
284 | // remove the track in case of failure | |
285 | if (!track->UpdateCovTrackParamAtCluster()) { | |
286 | fRecTracksPtr->Remove(track); | |
287 | fNRecTracks--; | |
288 | continue; | |
289 | } | |
290 | ||
291 | // save them | |
292 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); | |
293 | while (trackParam) { | |
294 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
295 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
296 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
297 | } | |
298 | ||
299 | } else { // or save track parameters on last station only | |
300 | ||
301 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); | |
302 | if (trackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { | |
303 | ||
304 | // save parameters from fit | |
305 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
306 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
307 | ||
308 | // save parameters extrapolated to the second chamber of the same station if it has been hit | |
309 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
310 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { | |
311 | ||
312 | // reset parameters and covariances | |
313 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
314 | nextTrackParam->SetZ(trackParam->GetZ()); | |
315 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
316 | ||
317 | // extrapolate them to the z of the corresponding cluster | |
318 | // remove the track in case of failure | |
319 | if (!AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ())) { | |
320 | fRecTracksPtr->Remove(track); | |
321 | fNRecTracks--; | |
322 | continue; | |
323 | } | |
324 | ||
325 | // save them | |
326 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
327 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
328 | ||
329 | } | |
330 | ||
331 | } | |
332 | ||
333 | } | |
334 | ||
335 | } | |
336 | ||
337 | // Look for compatible cluster(s) in station(0..) "station" | |
338 | if (!FollowTrackInStation(*track, clusterStore, station)) { | |
339 | ||
340 | // Try to recover track if required | |
341 | if (GetRecoParam()->RecoverTracks()) { | |
342 | ||
343 | // work on a copy of the track if this station is not required | |
344 | // to keep the case where no cluster is reconstructed as a possible candidate | |
345 | if (!GetRecoParam()->RequestStation(station)) { | |
346 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*track); | |
347 | fNRecTracks++; | |
348 | } | |
349 | ||
350 | // try to recover | |
351 | if (!RecoverTrack(*track, clusterStore, station)) { | |
352 | // remove track if no cluster found | |
353 | fRecTracksPtr->Remove(track); | |
354 | fNRecTracks--; | |
355 | } | |
356 | ||
357 | } else if (GetRecoParam()->RequestStation(station)) { | |
358 | // remove track if no cluster found | |
359 | fRecTracksPtr->Remove(track); | |
360 | fNRecTracks--; | |
361 | } | |
362 | ||
363 | } | |
364 | ||
365 | // abort tracking if there are too many candidates | |
366 | if (fNRecTracks > GetRecoParam()->GetMaxTrackCandidates()) { | |
367 | AliError(Form("Too many track candidates (%d tracks). Stop tracking.", fNRecTracks)); | |
368 | return kFALSE; | |
369 | } | |
370 | ||
371 | } | |
372 | ||
373 | // Compress fRecTracksPtr for the next step | |
374 | fRecTracksPtr->Compress(); | |
375 | ||
376 | // Keep only the best tracks if required | |
377 | if (!GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); | |
378 | ||
379 | } | |
380 | ||
381 | // Last fit of track candidates with all stations | |
382 | // Take into account the multiple scattering and remove bad tracks | |
383 | Int_t trackIndex = -1; | |
384 | track = (AliMUONTrack*) fRecTracksPtr->First(); | |
385 | while (track) { | |
386 | ||
387 | trackIndex++; | |
388 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
389 | ||
390 | Fit(*track, kTRUE, kFALSE, kTRUE); | |
391 | ||
392 | // Printout for debuging | |
393 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
394 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
395 | track->RecursiveDump(); | |
396 | } | |
397 | ||
398 | // Remove the track if the normalized chi2 is too high | |
399 | if (track->GetNormalizedChi2() > sigmaCut2) { | |
400 | fRecTracksPtr->Remove(track); | |
401 | fNRecTracks--; | |
402 | track = nextTrack; | |
403 | continue; | |
404 | } | |
405 | ||
406 | // save parameters from fit into smoothed parameters to complete track afterward | |
407 | if (GetRecoParam()->ComplementTracks()) { | |
408 | ||
409 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); | |
410 | if (trackParam->GetClusterPtr()->GetChamberId() < 2) { | |
411 | ||
412 | // save parameters from fit | |
413 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
414 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
415 | ||
416 | // save parameters extrapolated to the second chamber of the same station if it has been hit | |
417 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
418 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2) { | |
419 | ||
420 | // reset parameters and covariances | |
421 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
422 | nextTrackParam->SetZ(trackParam->GetZ()); | |
423 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
424 | ||
425 | // extrapolate them to the z of the corresponding cluster | |
426 | // remove the track in case of failure | |
427 | if (!AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ())) { | |
428 | fRecTracksPtr->Remove(track); | |
429 | fNRecTracks--; | |
430 | track = nextTrack; | |
431 | continue; | |
432 | } | |
433 | ||
434 | // save them | |
435 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
436 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
437 | ||
438 | } | |
439 | ||
440 | } | |
441 | ||
442 | } | |
443 | ||
444 | track = nextTrack; | |
445 | ||
446 | } | |
447 | ||
448 | fRecTracksPtr->Compress(); | |
449 | ||
450 | return kTRUE; | |
451 | ||
452 | } | |
453 | ||
454 | //__________________________________________________________________________ | |
455 | Bool_t AliMUONTrackReconstructor::FollowTrackInChamber(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextChamber) | |
456 | { | |
457 | /// Follow trackCandidate in chamber(0..) nextChamber and search for compatible cluster(s) | |
458 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
459 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
460 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
461 | /// Remove the obsolete "trackCandidate" at the end. | |
462 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
463 | AliDebug(1,Form("Enter FollowTrackInChamber(1..) %d", nextChamber+1)); | |
464 | ||
465 | Double_t chi2WithOneCluster = AliMUONTrack::MaxChi2(); | |
466 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * | |
467 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
468 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; | |
469 | Bool_t foundOneCluster = kFALSE; | |
470 | AliMUONTrack *newTrack = 0x0; | |
471 | AliMUONVCluster *cluster; | |
472 | AliMUONTrackParam extrapTrackParam; | |
473 | AliMUONTrackParam extrapTrackParamAtCh; | |
474 | AliMUONTrackParam extrapTrackParamAtCluster; | |
475 | AliMUONTrackParam bestTrackParamAtCluster; | |
476 | ||
477 | // Get track parameters according to the propagation direction | |
478 | if (nextChamber > 7) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
479 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
480 | ||
481 | // Printout for debuging | |
482 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
483 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
484 | extrapTrackParamAtCh.GetParameters().Print(); | |
485 | extrapTrackParamAtCh.GetCovariances().Print(); | |
486 | } | |
487 | ||
488 | // Add MCS effect | |
489 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
490 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(currentChamber),-1.); | |
491 | ||
492 | // Add MCS in the missing chamber(s) if any | |
493 | while (currentChamber > nextChamber + 1) { | |
494 | // extrapolation to the missing chamber | |
495 | currentChamber--; | |
496 | if (!AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber))) return kFALSE; | |
497 | // add MCS effect | |
498 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(currentChamber),-1.); | |
499 | } | |
500 | ||
501 | //Extrapolate trackCandidate to chamber | |
502 | if (!AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(nextChamber))) return kFALSE; | |
503 | ||
504 | // Printout for debuging | |
505 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
506 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(nextChamber)<<":"<<endl; | |
507 | extrapTrackParamAtCh.GetParameters().Print(); | |
508 | extrapTrackParamAtCh.GetCovariances().Print(); | |
509 | } | |
510 | ||
511 | // Printout for debuging | |
512 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
513 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << nextChamber+1 << endl; | |
514 | } | |
515 | ||
516 | // Ask the clustering to reconstruct new clusters around the track position in the current chamber | |
517 | // except for station 4 and 5 that are already entirely clusterized | |
518 | if (GetRecoParam()->CombineClusterTrackReco()) { | |
519 | if (nextChamber < 6) AskForNewClustersInChamber(extrapTrackParamAtCh, clusterStore, nextChamber); | |
520 | } | |
521 | ||
522 | // Create iterators to loop over clusters in both chambers | |
523 | TIter next(clusterStore.CreateChamberIterator(nextChamber,nextChamber)); | |
524 | ||
525 | // look for cluster in chamber | |
526 | while ( ( cluster = static_cast<AliMUONVCluster*>(next()) ) ) { | |
527 | ||
528 | // try to add the current cluster fast | |
529 | if (!TryOneClusterFast(extrapTrackParamAtCh, cluster)) continue; | |
530 | ||
531 | // try to add the current cluster accuratly | |
532 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, cluster, extrapTrackParamAtCluster); | |
533 | ||
534 | // if good chi2 then consider to add cluster | |
535 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
536 | foundOneCluster = kTRUE; | |
537 | ||
538 | // Printout for debuging | |
539 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
540 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << nextChamber+1 | |
541 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
542 | cluster->Print(); | |
543 | } | |
544 | ||
545 | if (GetRecoParam()->TrackAllTracks()) { | |
546 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
547 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
548 | UpdateTrack(*newTrack,extrapTrackParamAtCluster); | |
549 | fNRecTracks++; | |
550 | ||
551 | // Printout for debuging | |
552 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
553 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << nextChamber+1 << endl; | |
554 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
555 | } | |
556 | ||
557 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { | |
558 | // keep track of the best single cluster except if a couple of clusters has already been found | |
559 | bestChi2WithOneCluster = chi2WithOneCluster; | |
560 | bestTrackParamAtCluster = extrapTrackParamAtCluster; | |
561 | } | |
562 | ||
563 | } | |
564 | ||
565 | } | |
566 | ||
567 | // fill out the best track if required else clean up the fRecTracksPtr array | |
568 | if (!GetRecoParam()->TrackAllTracks()) { | |
569 | if (foundOneCluster) { | |
570 | UpdateTrack(trackCandidate,bestTrackParamAtCluster); | |
571 | ||
572 | // Printout for debuging | |
573 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
574 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster.GetClusterPtr()->GetChamberId()+1 << endl; | |
575 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
576 | } | |
577 | ||
578 | } else return kFALSE; | |
579 | ||
580 | } else if (foundOneCluster) { | |
581 | ||
582 | // remove obsolete track | |
583 | fRecTracksPtr->Remove(&trackCandidate); | |
584 | fNRecTracks--; | |
585 | ||
586 | } else return kFALSE; | |
587 | ||
588 | return kTRUE; | |
589 | ||
590 | } | |
591 | ||
592 | //__________________________________________________________________________ | |
593 | Bool_t AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) | |
594 | { | |
595 | /// Follow trackCandidate in station(0..) nextStation and search for compatible cluster(s) | |
596 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
597 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
598 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
599 | /// Remove the obsolete "trackCandidate" at the end. | |
600 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
601 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); | |
602 | ||
603 | // Order the chamber according to the propagation direction (tracking starts with chamber 2): | |
604 | // - nextStation == station(1...) 5 => forward propagation | |
605 | // - nextStation < station(1...) 5 => backward propagation | |
606 | Int_t ch1, ch2; | |
607 | if (nextStation==4) { | |
608 | ch1 = 2*nextStation+1; | |
609 | ch2 = 2*nextStation; | |
610 | } else { | |
611 | ch1 = 2*nextStation; | |
612 | ch2 = 2*nextStation+1; | |
613 | } | |
614 | ||
615 | Double_t chi2WithOneCluster = AliMUONTrack::MaxChi2(); | |
616 | Double_t chi2WithTwoClusters = AliMUONTrack::MaxChi2(); | |
617 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * | |
618 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
619 | Double_t maxChi2WithTwoClusters = 4. * GetRecoParam()->GetSigmaCutForTracking() * | |
620 | GetRecoParam()->GetSigmaCutForTracking(); // 4 because 4 quantities in chi2 | |
621 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; | |
622 | Double_t bestChi2WithTwoClusters = maxChi2WithTwoClusters; | |
623 | Bool_t foundOneCluster = kFALSE; | |
624 | Bool_t foundTwoClusters = kFALSE; | |
625 | AliMUONTrack *newTrack = 0x0; | |
626 | AliMUONVCluster *clusterCh1, *clusterCh2; | |
627 | AliMUONTrackParam extrapTrackParam; | |
628 | AliMUONTrackParam extrapTrackParamAtCh; | |
629 | AliMUONTrackParam extrapTrackParamAtCluster1; | |
630 | AliMUONTrackParam extrapTrackParamAtCluster2; | |
631 | AliMUONTrackParam bestTrackParamAtCluster1; | |
632 | AliMUONTrackParam bestTrackParamAtCluster2; | |
633 | ||
634 | // Get track parameters according to the propagation direction | |
635 | if (nextStation==4) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
636 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
637 | ||
638 | // Printout for debuging | |
639 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
640 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
641 | extrapTrackParamAtCh.GetParameters().Print(); | |
642 | extrapTrackParamAtCh.GetCovariances().Print(); | |
643 | } | |
644 | ||
645 | // Add MCS effect | |
646 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
647 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(currentChamber),-1.); | |
648 | ||
649 | // Add MCS in the missing chamber(s) if any | |
650 | while (ch1 < ch2 && currentChamber > ch2 + 1) { | |
651 | // extrapolation to the missing chamber | |
652 | currentChamber--; | |
653 | if (!AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber))) return kFALSE; | |
654 | // add MCS effect | |
655 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(currentChamber),-1.); | |
656 | } | |
657 | ||
658 | //Extrapolate trackCandidate to chamber "ch2" | |
659 | if (!AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2))) return kFALSE; | |
660 | ||
661 | // Printout for debuging | |
662 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
663 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch2)<<":"<<endl; | |
664 | extrapTrackParamAtCh.GetParameters().Print(); | |
665 | extrapTrackParamAtCh.GetCovariances().Print(); | |
666 | } | |
667 | ||
668 | // Printout for debuging | |
669 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
670 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << ch2+1 << endl; | |
671 | } | |
672 | ||
673 | // Ask the clustering to reconstruct new clusters around the track position in the current station | |
674 | // except for station 4 and 5 that are already entirely clusterized | |
675 | if (GetRecoParam()->CombineClusterTrackReco()) { | |
676 | if (nextStation < 3) AskForNewClustersInStation(extrapTrackParamAtCh, clusterStore, nextStation); | |
677 | } | |
678 | ||
679 | Int_t nClusters = clusterStore.GetSize(); | |
680 | Bool_t *clusterCh1Used = new Bool_t[nClusters]; | |
681 | for (Int_t i = 0; i < nClusters; i++) clusterCh1Used[i] = kFALSE; | |
682 | Int_t iCluster1; | |
683 | ||
684 | // Create iterators to loop over clusters in both chambers | |
685 | TIter nextInCh1(clusterStore.CreateChamberIterator(ch1,ch1)); | |
686 | TIter nextInCh2(clusterStore.CreateChamberIterator(ch2,ch2)); | |
687 | ||
688 | // look for candidates in chamber 2 | |
689 | while ( ( clusterCh2 = static_cast<AliMUONVCluster*>(nextInCh2()) ) ) { | |
690 | ||
691 | // try to add the current cluster fast | |
692 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh2)) continue; | |
693 | ||
694 | // try to add the current cluster accuratly | |
695 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh2, extrapTrackParamAtCluster2); | |
696 | ||
697 | // if good chi2 then try to attach a cluster in the other chamber too | |
698 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
699 | Bool_t foundSecondCluster = kFALSE; | |
700 | ||
701 | // Printout for debuging | |
702 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
703 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch2+1 | |
704 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
705 | clusterCh2->Print(); | |
706 | cout << " look for second clusters in chamber(1..): " << ch1+1 << " ..." << endl; | |
707 | } | |
708 | ||
709 | // add MCS effect for next step | |
710 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCluster2,AliMUONConstants::ChamberThicknessInX0(ch2),-1.); | |
711 | ||
712 | // copy new track parameters for next step | |
713 | extrapTrackParam = extrapTrackParamAtCluster2; | |
714 | ||
715 | //Extrapolate track parameters to chamber "ch1" | |
716 | Bool_t normalExtrap = AliMUONTrackExtrap::ExtrapToZ(&extrapTrackParam, AliMUONConstants::DefaultChamberZ(ch1)); | |
717 | ||
718 | // reset cluster iterator of chamber 1 | |
719 | nextInCh1.Reset(); | |
720 | iCluster1 = -1; | |
721 | ||
722 | // look for second candidates in chamber 1 | |
723 | if (normalExtrap) while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
724 | iCluster1++; | |
725 | ||
726 | // try to add the current cluster fast | |
727 | if (!TryOneClusterFast(extrapTrackParam, clusterCh1)) continue; | |
728 | ||
729 | // try to add the current cluster accurately | |
730 | chi2WithTwoClusters = TryTwoClusters(extrapTrackParamAtCluster2, clusterCh1, extrapTrackParamAtCluster1); | |
731 | ||
732 | // if good chi2 then create a new track by adding the 2 clusters to the "trackCandidate" | |
733 | if (chi2WithTwoClusters < maxChi2WithTwoClusters) { | |
734 | foundSecondCluster = kTRUE; | |
735 | foundTwoClusters = kTRUE; | |
736 | ||
737 | // Printout for debuging | |
738 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
739 | cout << "FollowTrackInStation: found second cluster in chamber(1..): " << ch1+1 | |
740 | << " (Global Chi2 = " << chi2WithTwoClusters << ")" << endl; | |
741 | clusterCh1->Print(); | |
742 | } | |
743 | ||
744 | if (GetRecoParam()->TrackAllTracks()) { | |
745 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new clusters | |
746 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
747 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,extrapTrackParamAtCluster2); | |
748 | fNRecTracks++; | |
749 | ||
750 | // Tag clusterCh1 as used | |
751 | clusterCh1Used[iCluster1] = kTRUE; | |
752 | ||
753 | // Printout for debuging | |
754 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
755 | cout << "FollowTrackInStation: added two clusters in station(1..): " << nextStation+1 << endl; | |
756 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
757 | } | |
758 | ||
759 | } else if (chi2WithTwoClusters < bestChi2WithTwoClusters) { | |
760 | // keep track of the best couple of clusters | |
761 | bestChi2WithTwoClusters = chi2WithTwoClusters; | |
762 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
763 | bestTrackParamAtCluster2 = extrapTrackParamAtCluster2; | |
764 | } | |
765 | ||
766 | } | |
767 | ||
768 | } | |
769 | ||
770 | // if no clusterCh1 found then consider to add clusterCh2 only | |
771 | if (!foundSecondCluster) { | |
772 | foundOneCluster = kTRUE; | |
773 | ||
774 | if (GetRecoParam()->TrackAllTracks()) { | |
775 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
776 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
777 | UpdateTrack(*newTrack,extrapTrackParamAtCluster2); | |
778 | fNRecTracks++; | |
779 | ||
780 | // Printout for debuging | |
781 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
782 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch2+1 << endl; | |
783 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
784 | } | |
785 | ||
786 | } else if (!foundTwoClusters && chi2WithOneCluster < bestChi2WithOneCluster) { | |
787 | // keep track of the best single cluster except if a couple of clusters has already been found | |
788 | bestChi2WithOneCluster = chi2WithOneCluster; | |
789 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster2; | |
790 | } | |
791 | ||
792 | } | |
793 | ||
794 | } | |
795 | ||
796 | } | |
797 | ||
798 | // look for candidates in chamber 1 not already attached to a track | |
799 | // if we want to keep all possible tracks or if no good couple of clusters has been found | |
800 | if (GetRecoParam()->TrackAllTracks() || !foundTwoClusters) { | |
801 | ||
802 | // add MCS effect for next step | |
803 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(ch2),-1.); | |
804 | ||
805 | //Extrapolate trackCandidate to chamber "ch1" | |
806 | Bool_t normalExtrap = AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch1)); | |
807 | ||
808 | // Printout for debuging | |
809 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
810 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch1)<<":"<<endl; | |
811 | extrapTrackParamAtCh.GetParameters().Print(); | |
812 | extrapTrackParamAtCh.GetCovariances().Print(); | |
813 | } | |
814 | ||
815 | // Printout for debuging | |
816 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
817 | cout << "FollowTrackInStation: look for single clusters in chamber(1..): " << ch1+1 << endl; | |
818 | } | |
819 | ||
820 | // reset cluster iterator of chamber 1 | |
821 | nextInCh1.Reset(); | |
822 | iCluster1 = -1; | |
823 | ||
824 | // look for second candidates in chamber 1 | |
825 | if (normalExtrap) while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
826 | iCluster1++; | |
827 | ||
828 | if (clusterCh1Used[iCluster1]) continue; // Skip cluster already used | |
829 | ||
830 | // try to add the current cluster fast | |
831 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh1)) continue; | |
832 | ||
833 | // try to add the current cluster accuratly | |
834 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh1, extrapTrackParamAtCluster1); | |
835 | ||
836 | // if good chi2 then consider to add clusterCh1 | |
837 | // We do not try to attach a cluster in the other chamber too since it has already been done above | |
838 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
839 | foundOneCluster = kTRUE; | |
840 | ||
841 | // Printout for debuging | |
842 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
843 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 | |
844 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
845 | clusterCh1->Print(); | |
846 | } | |
847 | ||
848 | if (GetRecoParam()->TrackAllTracks()) { | |
849 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
850 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
851 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1); | |
852 | fNRecTracks++; | |
853 | ||
854 | // Printout for debuging | |
855 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
856 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch1+1 << endl; | |
857 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
858 | } | |
859 | ||
860 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { | |
861 | // keep track of the best single cluster except if a couple of clusters has already been found | |
862 | bestChi2WithOneCluster = chi2WithOneCluster; | |
863 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
864 | } | |
865 | ||
866 | } | |
867 | ||
868 | } | |
869 | ||
870 | } | |
871 | ||
872 | // fill out the best track if required else clean up the fRecTracksPtr array | |
873 | if (!GetRecoParam()->TrackAllTracks()) { | |
874 | if (foundTwoClusters) { | |
875 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestTrackParamAtCluster2); | |
876 | ||
877 | // Printout for debuging | |
878 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
879 | cout << "FollowTrackInStation: added the two best clusters in station(1..): " << nextStation+1 << endl; | |
880 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
881 | } | |
882 | ||
883 | } else if (foundOneCluster) { | |
884 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1); | |
885 | ||
886 | // Printout for debuging | |
887 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
888 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster1.GetClusterPtr()->GetChamberId()+1 << endl; | |
889 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
890 | } | |
891 | ||
892 | } else { | |
893 | delete [] clusterCh1Used; | |
894 | return kFALSE; | |
895 | } | |
896 | ||
897 | } else if (foundOneCluster || foundTwoClusters) { | |
898 | ||
899 | // remove obsolete track | |
900 | fRecTracksPtr->Remove(&trackCandidate); | |
901 | fNRecTracks--; | |
902 | ||
903 | } else { | |
904 | delete [] clusterCh1Used; | |
905 | return kFALSE; | |
906 | } | |
907 | ||
908 | delete [] clusterCh1Used; | |
909 | return kTRUE; | |
910 | ||
911 | } | |
912 | ||
913 | //__________________________________________________________________________ | |
914 | Double_t AliMUONTrackReconstructor::TryTwoClusters(const AliMUONTrackParam &trackParamAtCluster1, AliMUONVCluster* cluster2, | |
915 | AliMUONTrackParam &trackParamAtCluster2) | |
916 | { | |
917 | /// Test the compatibility between the track and the 2 clusters together (using trackParam's covariance matrix): | |
918 | /// return the corresponding Chi2 accounting for covariances between the 2 clusters | |
919 | /// return trackParamAtCluster1 & 2 | |
920 | ||
921 | // extrapolate track parameters at the z position of the second cluster (no need to extrapolate the covariances) | |
922 | // and set pointer to cluster into trackParamAtCluster | |
923 | trackParamAtCluster2.SetParameters(trackParamAtCluster1.GetParameters()); | |
924 | trackParamAtCluster2.SetZ(trackParamAtCluster1.GetZ()); | |
925 | trackParamAtCluster2.SetClusterPtr(cluster2); | |
926 | if (!AliMUONTrackExtrap::ExtrapToZ(&trackParamAtCluster2, cluster2->GetZ())) return 2.*AliMUONTrack::MaxChi2(); | |
927 | ||
928 | // Set differences between track and the 2 clusters in the bending and non bending directions | |
929 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
930 | TMatrixD dPos(4,1); | |
931 | dPos(0,0) = cluster1->GetX() - trackParamAtCluster1.GetNonBendingCoor(); | |
932 | dPos(1,0) = cluster1->GetY() - trackParamAtCluster1.GetBendingCoor(); | |
933 | dPos(2,0) = cluster2->GetX() - trackParamAtCluster2.GetNonBendingCoor(); | |
934 | dPos(3,0) = cluster2->GetY() - trackParamAtCluster2.GetBendingCoor(); | |
935 | ||
936 | // Calculate the error matrix from the track parameter covariances at first cluster | |
937 | TMatrixD error(4,4); | |
938 | error.Zero(); | |
939 | if (trackParamAtCluster1.CovariancesExist()) { | |
940 | // Save track parameters at first cluster | |
941 | TMatrixD paramAtCluster1Save(trackParamAtCluster1.GetParameters()); | |
942 | ||
943 | // Save track coordinates at second cluster | |
944 | Double_t nonBendingCoor2 = trackParamAtCluster2.GetNonBendingCoor(); | |
945 | Double_t bendingCoor2 = trackParamAtCluster2.GetBendingCoor(); | |
946 | ||
947 | // copy track parameters at first cluster for jacobian calculation | |
948 | AliMUONTrackParam trackParam(trackParamAtCluster1); | |
949 | ||
950 | // Get the pointer to the parameter covariance matrix at first cluster | |
951 | const TMatrixD& kParamCov = trackParam.GetCovariances(); | |
952 | ||
953 | // Calculate the jacobian related to the transformation between track parameters | |
954 | // at first cluster and track coordinates at the 2 cluster z-positions | |
955 | TMatrixD jacob(4,5); | |
956 | jacob.Zero(); | |
957 | // first derivative at the first cluster: | |
958 | jacob(0,0) = 1.; // dx1/dx | |
959 | jacob(1,2) = 1.; // dy1/dy | |
960 | // first derivative at the second cluster: | |
961 | TMatrixD dParam(5,1); | |
962 | Double_t direction[5] = {-1.,-1.,1.,1.,-1.}; | |
963 | for (Int_t i=0; i<5; i++) { | |
964 | // Skip jacobian calculation for parameters with no associated error | |
965 | if (kParamCov(i,i) == 0.) continue; | |
966 | // Small variation of parameter i only | |
967 | for (Int_t j=0; j<5; j++) { | |
968 | if (j==i) { | |
969 | dParam(j,0) = TMath::Sqrt(kParamCov(i,i)); | |
970 | dParam(j,0) *= TMath::Sign(1.,direction[j]*paramAtCluster1Save(j,0)); // variation always in the same direction | |
971 | } else dParam(j,0) = 0.; | |
972 | } | |
973 | ||
974 | // Set new track parameters at first cluster | |
975 | trackParam.SetParameters(paramAtCluster1Save); | |
976 | trackParam.AddParameters(dParam); | |
977 | trackParam.SetZ(cluster1->GetZ()); | |
978 | ||
979 | // Extrapolate new track parameters to the z position of the second cluster | |
980 | if (!AliMUONTrackExtrap::ExtrapToZ(&trackParam,cluster2->GetZ())) return 2.*AliMUONTrack::MaxChi2(); | |
981 | ||
982 | // Calculate the jacobian | |
983 | jacob(2,i) = (trackParam.GetNonBendingCoor() - nonBendingCoor2) / dParam(i,0); // dx2/dParami | |
984 | jacob(3,i) = (trackParam.GetBendingCoor() - bendingCoor2 ) / dParam(i,0); // dy2/dParami | |
985 | } | |
986 | ||
987 | // Calculate the error matrix | |
988 | TMatrixD tmp(jacob,TMatrixD::kMult,kParamCov); | |
989 | error = TMatrixD(tmp,TMatrixD::kMultTranspose,jacob); | |
990 | } | |
991 | ||
992 | // Add cluster resolution to the error matrix | |
993 | error(0,0) += cluster1->GetErrX2(); | |
994 | error(1,1) += cluster1->GetErrY2(); | |
995 | error(2,2) += cluster2->GetErrX2(); | |
996 | error(3,3) += cluster2->GetErrY2(); | |
997 | ||
998 | // invert the error matrix for Chi2 calculation | |
999 | if (error.Determinant() != 0) { | |
1000 | error.Invert(); | |
1001 | } else { | |
1002 | AliWarning(" Determinant error=0"); | |
1003 | return 2.*AliMUONTrack::MaxChi2(); | |
1004 | } | |
1005 | ||
1006 | // Compute the Chi2 value | |
1007 | TMatrixD tmp2(dPos,TMatrixD::kTransposeMult,error); | |
1008 | TMatrixD result(tmp2,TMatrixD::kMult,dPos); | |
1009 | ||
1010 | return result(0,0); | |
1011 | ||
1012 | } | |
1013 | ||
1014 | //__________________________________________________________________________ | |
1015 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster) | |
1016 | { | |
1017 | /// Add 1 cluster to the track candidate | |
1018 | /// Update chi2 of the track | |
1019 | ||
1020 | // Compute local chi2 | |
1021 | AliMUONVCluster* cluster = trackParamAtCluster.GetClusterPtr(); | |
1022 | Double_t deltaX = trackParamAtCluster.GetNonBendingCoor() - cluster->GetX(); | |
1023 | Double_t deltaY = trackParamAtCluster.GetBendingCoor() - cluster->GetY(); | |
1024 | Double_t localChi2 = deltaX*deltaX / cluster->GetErrX2() + | |
1025 | deltaY*deltaY / cluster->GetErrY2(); | |
1026 | ||
1027 | // Flag cluster as being not removable | |
1028 | if (GetRecoParam()->RequestStation(cluster->GetChamberId()/2)) | |
1029 | trackParamAtCluster.SetRemovable(kFALSE); | |
1030 | else trackParamAtCluster.SetRemovable(kTRUE); | |
1031 | trackParamAtCluster.SetLocalChi2(0.); // --> Local chi2 not used | |
1032 | ||
1033 | // Update the chi2 of the new track | |
1034 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2); | |
1035 | ||
1036 | // Update TrackParamAtCluster | |
1037 | track.AddTrackParamAtCluster(trackParamAtCluster,*cluster); | |
1038 | ||
1039 | } | |
1040 | ||
1041 | //__________________________________________________________________________ | |
1042 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster1, AliMUONTrackParam &trackParamAtCluster2) | |
1043 | { | |
1044 | /// Add 2 clusters to the track candidate | |
1045 | /// Update track and local chi2 | |
1046 | ||
1047 | // Update local chi2 at first cluster | |
1048 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
1049 | Double_t deltaX = trackParamAtCluster1.GetNonBendingCoor() - cluster1->GetX(); | |
1050 | Double_t deltaY = trackParamAtCluster1.GetBendingCoor() - cluster1->GetY(); | |
1051 | Double_t localChi2AtCluster1 = deltaX*deltaX / cluster1->GetErrX2() + | |
1052 | deltaY*deltaY / cluster1->GetErrY2(); | |
1053 | trackParamAtCluster1.SetLocalChi2(localChi2AtCluster1); | |
1054 | ||
1055 | // Flag first cluster as being removable | |
1056 | trackParamAtCluster1.SetRemovable(kTRUE); | |
1057 | ||
1058 | // Update local chi2 at second cluster | |
1059 | AliMUONVCluster* cluster2 = trackParamAtCluster2.GetClusterPtr(); | |
1060 | deltaX = trackParamAtCluster2.GetNonBendingCoor() - cluster2->GetX(); | |
1061 | deltaY = trackParamAtCluster2.GetBendingCoor() - cluster2->GetY(); | |
1062 | Double_t localChi2AtCluster2 = deltaX*deltaX / cluster2->GetErrX2() + | |
1063 | deltaY*deltaY / cluster2->GetErrY2(); | |
1064 | trackParamAtCluster2.SetLocalChi2(localChi2AtCluster2); | |
1065 | ||
1066 | // Flag first cluster as being removable | |
1067 | trackParamAtCluster2.SetRemovable(kTRUE); | |
1068 | ||
1069 | // Update the chi2 of the new track | |
1070 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2AtCluster1 + localChi2AtCluster2); | |
1071 | ||
1072 | // Update TrackParamAtCluster | |
1073 | track.AddTrackParamAtCluster(trackParamAtCluster1,*cluster1); | |
1074 | track.AddTrackParamAtCluster(trackParamAtCluster2,*cluster2); | |
1075 | ||
1076 | } | |
1077 | ||
1078 | //__________________________________________________________________________ | |
1079 | Bool_t AliMUONTrackReconstructor::RecoverTrack(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) | |
1080 | { | |
1081 | /// Try to recover the track candidate in the next station | |
1082 | /// by removing the worst of the two clusters attached in the current station | |
1083 | /// Return kTRUE if recovering succeeds | |
1084 | AliDebug(1,"Enter RecoverTrack"); | |
1085 | ||
1086 | // Do not try to recover track until we have attached cluster(s) on station(1..) 3 | |
1087 | if (nextStation > 1) return kFALSE; | |
1088 | ||
1089 | Int_t worstClusterNumber = -1; | |
1090 | Double_t localChi2, worstLocalChi2 = -1.; | |
1091 | ||
1092 | // Look for the cluster to remove | |
1093 | for (Int_t clusterNumber = 0; clusterNumber < 2; clusterNumber++) { | |
1094 | AliMUONTrackParam *trackParamAtCluster = (AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(clusterNumber); | |
1095 | ||
1096 | // check if current cluster is in the previous station | |
1097 | if (trackParamAtCluster->GetClusterPtr()->GetChamberId()/2 != nextStation+1) break; | |
1098 | ||
1099 | // check if current cluster is removable | |
1100 | if (!trackParamAtCluster->IsRemovable()) return kFALSE; | |
1101 | ||
1102 | // reset the current cluster as beig not removable if it is on a required station | |
1103 | if (GetRecoParam()->RequestStation(nextStation+1)) trackParamAtCluster->SetRemovable(kFALSE); | |
1104 | ||
1105 | // Pick up cluster with the worst chi2 | |
1106 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1107 | if (localChi2 > worstLocalChi2) { | |
1108 | worstLocalChi2 = localChi2; | |
1109 | worstClusterNumber = clusterNumber; | |
1110 | } | |
1111 | ||
1112 | } | |
1113 | ||
1114 | // check if worst cluster found | |
1115 | if (worstClusterNumber < 0) return kFALSE; | |
1116 | ||
1117 | // Remove the worst cluster | |
1118 | trackCandidate.RemoveTrackParamAtCluster((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(worstClusterNumber)); | |
1119 | ||
1120 | // Re-fit the track: | |
1121 | // Do not take into account the multiple scattering to speed up the fit | |
1122 | // Calculate the track parameter covariance matrix | |
1123 | Fit(trackCandidate, kFALSE, kFALSE, kTRUE); | |
1124 | ||
1125 | // skip track if the normalized chi2 is too high | |
1126 | if (trackCandidate.GetNormalizedChi2() > GetRecoParam()->GetSigmaCutForTracking() * GetRecoParam()->GetSigmaCutForTracking()) return kFALSE; | |
1127 | ||
1128 | // skip track out of limits | |
1129 | if (!IsAcceptable(*((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First()))) return kFALSE; | |
1130 | ||
1131 | // Look for new cluster(s) in next station | |
1132 | return FollowTrackInStation(trackCandidate,clusterStore,nextStation); | |
1133 | ||
1134 | } | |
1135 | ||
1136 | //__________________________________________________________________________ | |
1137 | void AliMUONTrackReconstructor::SetVertexErrXY2ForFit(AliMUONTrack &trackCandidate) | |
1138 | { | |
1139 | /// Compute the vertex resolution square from natural vertex dispersion and | |
1140 | /// multiple scattering effets according to trackCandidate path in absorber | |
1141 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
1142 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
1143 | AliDebug(1,"Enter SetVertexForFit"); | |
1144 | ||
1145 | Double_t nonBendingReso2 = GetRecoParam()->GetNonBendingVertexDispersion() * | |
1146 | GetRecoParam()->GetNonBendingVertexDispersion(); | |
1147 | Double_t bendingReso2 = GetRecoParam()->GetBendingVertexDispersion() * | |
1148 | GetRecoParam()->GetBendingVertexDispersion(); | |
1149 | ||
1150 | // add multiple scattering effets | |
1151 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate.GetTrackParamAtCluster()->First()))); | |
1152 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering | |
1153 | if (!AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex,AliMUONConstants::AbsZEnd())) { | |
1154 | nonBendingReso2 = 0.; | |
1155 | bendingReso2 = 0.; | |
1156 | } else { | |
1157 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
1158 | const TMatrixD& kParamCov = paramAtVertex.GetCovariances(); | |
1159 | nonBendingReso2 += kParamCov(0,0); | |
1160 | bendingReso2 += kParamCov(2,2); | |
1161 | } | |
1162 | ||
1163 | // Set the vertex resolution square | |
1164 | trackCandidate.SetVertexErrXY2(nonBendingReso2,bendingReso2); | |
1165 | } | |
1166 | ||
1167 | //__________________________________________________________________________ | |
1168 | void AliMUONTrackReconstructor::Fit(AliMUONTrack &track, Bool_t includeMCS, Bool_t fitWithVertex, Bool_t calcCov) | |
1169 | { | |
1170 | /// Fit the track | |
1171 | /// w/wo multiple Coulomb scattering according to "includeMCS". | |
1172 | /// w/wo constraining the vertex according to "fitWithVertex". | |
1173 | /// calculating or not the covariance matrix according to "calcCov". | |
1174 | AliDebug(1,"Enter Fit"); | |
1175 | ||
1176 | Double_t benC, errorParam, invBenP, nonBenC, x, y; | |
1177 | AliMUONTrackParam *trackParam; | |
1178 | Double_t arg[1], fedm, errdef, globalChi2; | |
1179 | Int_t npari, nparx; | |
1180 | Int_t status, covStatus; | |
1181 | ||
1182 | // Instantiate gMinuit if not already done | |
1183 | if (!gMinuit) gMinuit = new TMinuit(6); | |
1184 | // Clear MINUIT parameters | |
1185 | gMinuit->mncler(); | |
1186 | // Give the fitted track to MINUIT | |
1187 | gMinuit->SetObjectFit(&track); | |
1188 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
1189 | // Define print level | |
1190 | arg[0] = 1; | |
1191 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1192 | // Print covariance matrix | |
1193 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
1194 | } else { | |
1195 | arg[0] = -1; | |
1196 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1197 | } | |
1198 | // No warnings | |
1199 | gMinuit->mnexcm("SET NOW", arg, 0, status); | |
1200 | // Define strategy | |
1201 | //arg[0] = 2; | |
1202 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
1203 | ||
1204 | // set flag w/wo multiple scattering according to "includeMCS" | |
1205 | track.FitWithMCS(includeMCS); | |
1206 | if (includeMCS) { | |
1207 | // compute cluster weights only once | |
1208 | if (!track.UpdateTrackParamAtCluster() || !track.ComputeClusterWeights()) { | |
1209 | AliWarning("cannot take into account the multiple scattering effects"); | |
1210 | track.FitWithMCS(kFALSE); | |
1211 | } | |
1212 | } | |
1213 | ||
1214 | track.FitWithVertex(fitWithVertex); | |
1215 | if (fitWithVertex) SetVertexErrXY2ForFit(track); | |
1216 | ||
1217 | // Set fitting function | |
1218 | gMinuit->SetFCN(TrackChi2); | |
1219 | ||
1220 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
1221 | // Mandatory limits to avoid NaN values of parameters | |
1222 | trackParam = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->First()); | |
1223 | Double_t maxIBM = 1. / GetRecoParam()->GetMinBendingMomentum(); | |
1224 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); | |
1225 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -1., 1., status); | |
1226 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); | |
1227 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -1.5, 1.5, status); | |
1228 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -maxIBM, maxIBM, status); | |
1229 | ||
1230 | // minimization | |
1231 | gMinuit->mnexcm("MIGRAD", arg, 0, status); | |
1232 | ||
1233 | // Calculate the covariance matrix more accurately if required | |
1234 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
1235 | ||
1236 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") | |
1237 | gMinuit->GetParameter(0, x, errorParam); | |
1238 | trackParam->SetNonBendingCoor(x); | |
1239 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
1240 | trackParam->SetNonBendingSlope(nonBenC); | |
1241 | gMinuit->GetParameter(2, y, errorParam); | |
1242 | trackParam->SetBendingCoor(y); | |
1243 | gMinuit->GetParameter(3, benC, errorParam); | |
1244 | trackParam->SetBendingSlope(benC); | |
1245 | gMinuit->GetParameter(4, invBenP, errorParam); | |
1246 | trackParam->SetInverseBendingMomentum(invBenP); | |
1247 | ||
1248 | // global result of the fit | |
1249 | gMinuit->mnstat(globalChi2, fedm, errdef, npari, nparx, covStatus); | |
1250 | track.SetGlobalChi2(globalChi2); | |
1251 | ||
1252 | // Get the covariance matrix if required | |
1253 | if (calcCov) { | |
1254 | // Covariance matrix according to HESSE status | |
1255 | // If problem then keep only the diagonal terms (variances) | |
1256 | Double_t matrix[5][5]; | |
1257 | for (Int_t i=0; i<5; i++) for (Int_t j=0; j<5; j++) matrix[i][j] = 0.; | |
1258 | gMinuit->mnemat(&matrix[0][0],5); | |
1259 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
1260 | else trackParam->SetVariances(matrix); | |
1261 | } else trackParam->DeleteCovariances(); | |
1262 | ||
1263 | } | |
1264 | ||
1265 | //__________________________________________________________________________ | |
1266 | void TrackChi2(Int_t & /*nParam*/, Double_t * /*gradient*/, Double_t &chi2, Double_t *param, Int_t /*flag*/) | |
1267 | { | |
1268 | /// Return the "Chi2" to be minimized with Minuit for track fitting. | |
1269 | /// Assumes that the trackParamAtCluster are sorted according to increasing Z. | |
1270 | /// Track parameters at each cluster are updated accordingly. | |
1271 | /// Vertex is used according to the flag "trackBeingFitted->GetFitWithVertex()". | |
1272 | /// Multiple Coulomb scattering is taken into account according to the flag "trackBeingFitted->GetFitWithMCS()". | |
1273 | ||
1274 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
1275 | AliMUONTrackParam* trackParamAtCluster = (AliMUONTrackParam*) trackBeingFitted->GetTrackParamAtCluster()->First(); | |
1276 | Double_t dX, dY; | |
1277 | chi2 = 0.; // initialize chi2 | |
1278 | ||
1279 | // update track parameters | |
1280 | trackParamAtCluster->SetNonBendingCoor(param[0]); | |
1281 | trackParamAtCluster->SetNonBendingSlope(param[1]); | |
1282 | trackParamAtCluster->SetBendingCoor(param[2]); | |
1283 | trackParamAtCluster->SetBendingSlope(param[3]); | |
1284 | trackParamAtCluster->SetInverseBendingMomentum(param[4]); | |
1285 | if (!trackBeingFitted->UpdateTrackParamAtCluster()) { | |
1286 | chi2 = 2.*AliMUONTrack::MaxChi2(); | |
1287 | return; | |
1288 | } | |
1289 | ||
1290 | // Take the vertex into account in the fit if required | |
1291 | if (trackBeingFitted->FitWithVertex()) { | |
1292 | Double_t nonBendingReso2,bendingReso2; | |
1293 | trackBeingFitted->GetVertexErrXY2(nonBendingReso2,bendingReso2); | |
1294 | AliMUONTrackParam paramAtVertex(*trackParamAtCluster); | |
1295 | if (nonBendingReso2 != 0. && bendingReso2 != 0. && AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.)) { // vextex position = (0,0,0) | |
1296 | dX = paramAtVertex.GetNonBendingCoor(); | |
1297 | dY = paramAtVertex.GetBendingCoor(); | |
1298 | chi2 += dX * dX / nonBendingReso2 + dY * dY / bendingReso2; | |
1299 | } else { | |
1300 | chi2 = 2.*AliMUONTrack::MaxChi2(); | |
1301 | return; | |
1302 | } | |
1303 | } | |
1304 | ||
1305 | // compute chi2 w/wo multiple scattering | |
1306 | chi2 += trackBeingFitted->ComputeGlobalChi2(trackBeingFitted->FitWithMCS()); | |
1307 | ||
1308 | } | |
1309 | ||
1310 | //__________________________________________________________________________ | |
1311 | Bool_t AliMUONTrackReconstructor::ComplementTracks(const AliMUONVClusterStore& clusterStore) | |
1312 | { | |
1313 | /// Complete tracks by adding missing clusters (if there is an overlap between | |
1314 | /// two detection elements, the track may have two clusters in the same chamber). | |
1315 | /// Re-fit track parameters and covariances. | |
1316 | /// Return kTRUE if one or more tracks have been complemented. | |
1317 | AliDebug(1,"Enter ComplementTracks"); | |
1318 | ||
1319 | Int_t chamberId, detElemId; | |
1320 | Double_t chi2OfCluster, bestChi2OfCluster; | |
1321 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * | |
1322 | GetRecoParam()->GetSigmaCutForTracking(); | |
1323 | Bool_t foundOneCluster, trackModified, hasChanged = kFALSE; | |
1324 | AliMUONVCluster* cluster; | |
1325 | AliMUONTrackParam *trackParam, *nextTrackParam, copyOfTrackParam, trackParamAtCluster, bestTrackParamAtCluster; | |
1326 | ||
1327 | AliMUONTrack *track = (AliMUONTrack*) fRecTracksPtr->First(); | |
1328 | while (track) { | |
1329 | trackModified = kFALSE; | |
1330 | ||
1331 | trackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->First(); | |
1332 | while (trackParam) { | |
1333 | foundOneCluster = kFALSE; | |
1334 | bestChi2OfCluster = 2. * sigmaCut2; // 2 because 2 quantities in chi2 | |
1335 | chamberId = trackParam->GetClusterPtr()->GetChamberId(); | |
1336 | detElemId = trackParam->GetClusterPtr()->GetDetElemId(); | |
1337 | ||
1338 | // prepare nextTrackParam before adding new cluster because of the sorting | |
1339 | nextTrackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->After(trackParam); | |
1340 | ||
1341 | // recover track parameters from local fit and put them into a copy of trackParam | |
1342 | copyOfTrackParam.SetZ(trackParam->GetZ()); | |
1343 | copyOfTrackParam.SetParameters(trackParam->GetSmoothParameters()); | |
1344 | copyOfTrackParam.SetCovariances(trackParam->GetSmoothCovariances()); | |
1345 | ||
1346 | // Create iterators to loop over clusters in current chamber | |
1347 | TIter nextInCh(clusterStore.CreateChamberIterator(chamberId,chamberId)); | |
1348 | ||
1349 | // look for one second candidate in the same chamber | |
1350 | while ( ( cluster = static_cast<AliMUONVCluster*>(nextInCh()) ) ) { | |
1351 | ||
1352 | // look for a cluster in another detection element | |
1353 | if (cluster->GetDetElemId() == detElemId) continue; | |
1354 | ||
1355 | // try to add the current cluster fast | |
1356 | if (!TryOneClusterFast(copyOfTrackParam, cluster)) continue; | |
1357 | ||
1358 | // try to add the current cluster accurately | |
1359 | chi2OfCluster = TryOneCluster(copyOfTrackParam, cluster, trackParamAtCluster); | |
1360 | ||
1361 | // if better chi2 then prepare to add this cluster to the track | |
1362 | if (chi2OfCluster < bestChi2OfCluster) { | |
1363 | bestChi2OfCluster = chi2OfCluster; | |
1364 | bestTrackParamAtCluster = trackParamAtCluster; | |
1365 | foundOneCluster = kTRUE; | |
1366 | } | |
1367 | ||
1368 | } | |
1369 | ||
1370 | // add new cluster if any | |
1371 | if (foundOneCluster) { | |
1372 | ||
1373 | // Printout for debuging | |
1374 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1375 | cout << "ComplementTracks: found one cluster in chamber(1..): " << chamberId+1 << endl; | |
1376 | bestTrackParamAtCluster.GetClusterPtr()->Print(); | |
1377 | cout<<endl<<"Track parameters and covariances at cluster:"<<endl; | |
1378 | bestTrackParamAtCluster.GetParameters().Print(); | |
1379 | bestTrackParamAtCluster.GetCovariances().Print(); | |
1380 | } | |
1381 | ||
1382 | trackParam->SetRemovable(kTRUE); | |
1383 | bestTrackParamAtCluster.SetRemovable(kTRUE); | |
1384 | track->AddTrackParamAtCluster(bestTrackParamAtCluster,*(bestTrackParamAtCluster.GetClusterPtr())); | |
1385 | trackModified = kTRUE; | |
1386 | hasChanged = kTRUE; | |
1387 | } | |
1388 | ||
1389 | trackParam = nextTrackParam; | |
1390 | } | |
1391 | ||
1392 | // re-fit track parameters if needed | |
1393 | if (trackModified) Fit(*track, kTRUE, kFALSE, kTRUE); | |
1394 | ||
1395 | track = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1396 | } | |
1397 | ||
1398 | return hasChanged; | |
1399 | ||
1400 | } | |
1401 | ||
1402 | //__________________________________________________________________________ | |
1403 | void AliMUONTrackReconstructor::ImproveTrack(AliMUONTrack &track) | |
1404 | { | |
1405 | /// Improve the given track by removing clusters with local chi2 highter than the defined cut | |
1406 | /// Recompute track parameters and covariances at the remaining clusters | |
1407 | AliDebug(1,"Enter ImproveTrack"); | |
1408 | ||
1409 | Double_t localChi2, worstLocalChi2; | |
1410 | AliMUONTrackParam *trackParamAtCluster, *worstTrackParamAtCluster; | |
1411 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForImprovement() * | |
1412 | GetRecoParam()->GetSigmaCutForImprovement(); | |
1413 | ||
1414 | while (!track.IsImproved()) { | |
1415 | ||
1416 | // identify removable clusters | |
1417 | track.TagRemovableClusters(GetRecoParam()->RequestedStationMask()); | |
1418 | ||
1419 | // Update track parameters and covariances | |
1420 | if (!track.UpdateCovTrackParamAtCluster()) { | |
1421 | AliWarning("unable to update track parameters and covariances --> stop improvement"); | |
1422 | break; | |
1423 | } | |
1424 | ||
1425 | // Compute local chi2 of each clusters | |
1426 | track.ComputeLocalChi2(kTRUE); | |
1427 | ||
1428 | // Look for the cluster to remove | |
1429 | worstTrackParamAtCluster = NULL; | |
1430 | worstLocalChi2 = 0.; | |
1431 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1432 | while (trackParamAtCluster) { | |
1433 | ||
1434 | // Pick up cluster with the worst chi2 | |
1435 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1436 | if (localChi2 > worstLocalChi2) { | |
1437 | worstLocalChi2 = localChi2; | |
1438 | worstTrackParamAtCluster = trackParamAtCluster; | |
1439 | } | |
1440 | ||
1441 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(trackParamAtCluster); | |
1442 | } | |
1443 | ||
1444 | // Check if worst cluster found | |
1445 | if (!worstTrackParamAtCluster) { | |
1446 | AliWarning("Bad local chi2 values?"); | |
1447 | break; | |
1448 | } | |
1449 | ||
1450 | // Check whether the worst chi2 is under requirement or not | |
1451 | if (worstLocalChi2 < 2. * sigmaCut2) { // 2 because 2 quantities in chi2 | |
1452 | track.SetImproved(kTRUE); | |
1453 | break; | |
1454 | } | |
1455 | ||
1456 | // if the worst cluster is not removable then stop improvement | |
1457 | if (!worstTrackParamAtCluster->IsRemovable()) break; | |
1458 | ||
1459 | // Remove the worst cluster | |
1460 | track.RemoveTrackParamAtCluster(worstTrackParamAtCluster); | |
1461 | ||
1462 | // Re-fit the track: | |
1463 | // Take into account the multiple scattering | |
1464 | // Calculate the track parameter covariance matrix | |
1465 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1466 | ||
1467 | // Printout for debuging | |
1468 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1469 | cout << "ImproveTracks: track " << fRecTracksPtr->IndexOf(&track)+1 << " improved " << endl; | |
1470 | } | |
1471 | ||
1472 | } | |
1473 | ||
1474 | } | |
1475 | ||
1476 | //__________________________________________________________________________ | |
1477 | Bool_t AliMUONTrackReconstructor::FinalizeTrack(AliMUONTrack &track) | |
1478 | { | |
1479 | /// Recompute track parameters and covariances at each attached cluster | |
1480 | /// from those at the first one, if not already done | |
1481 | AliDebug(1,"Enter FinalizeTrack"); | |
1482 | if (!track.IsImproved() && !track.UpdateCovTrackParamAtCluster()) { | |
1483 | AliWarning("finalization failed due to extrapolation problem"); | |
1484 | return kFALSE; | |
1485 | } | |
1486 | return kTRUE; | |
1487 | } | |
1488 | ||
1489 | //__________________________________________________________________________ | |
1490 | Bool_t AliMUONTrackReconstructor::RefitTrack(AliMUONTrack &track, Bool_t enableImprovement) | |
1491 | { | |
1492 | /// re-fit the given track | |
1493 | ||
1494 | // check validity of the track | |
1495 | if (track.GetNClusters() < 3) { | |
1496 | AliWarning("the track does not contain enough clusters --> unable to refit"); | |
1497 | return kFALSE; | |
1498 | } | |
1499 | ||
1500 | // reset the seed (i.e. parameters at first cluster) before fitting | |
1501 | AliMUONTrackParam* firstTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1502 | if (firstTrackParam->GetInverseBendingMomentum() == 0.) { | |
1503 | AliWarning("track parameters at first chamber are not initialized --> unable to refit"); | |
1504 | return kFALSE; | |
1505 | } | |
1506 | ||
1507 | // compute track parameters at each cluster from parameters at the first one | |
1508 | // necessary to compute multiple scattering effect during refitting | |
1509 | if (!track.UpdateTrackParamAtCluster()) { | |
1510 | AliWarning("bad track refitting due to extrapolation failure"); | |
1511 | return kFALSE; | |
1512 | } | |
1513 | ||
1514 | // Re-fit the track: | |
1515 | // Take into account the multiple scattering | |
1516 | // Calculate the track parameter covariance matrix | |
1517 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1518 | ||
1519 | // Improve the reconstructed tracks if required | |
1520 | track.SetImproved(kFALSE); | |
1521 | if (enableImprovement && GetRecoParam()->ImproveTracks()) ImproveTrack(track); | |
1522 | ||
1523 | // Fill AliMUONTrack data members | |
1524 | if (track.GetGlobalChi2() < AliMUONTrack::MaxChi2()) return FinalizeTrack(track); | |
1525 | else { | |
1526 | AliWarning("track not finalized due to extrapolation failure"); | |
1527 | return kFALSE; | |
1528 | } | |
1529 | ||
1530 | } | |
1531 |