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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 AliMUONTrackReconstructorK | |
20 | /// | |
21 | /// MUON track reconstructor using the kalman method | |
22 | /// | |
23 | /// This class contains as data: | |
24 | /// - the parameters for the track reconstruction | |
25 | /// | |
26 | /// It contains as methods, among others: | |
27 | /// - MakeTracks to build the tracks | |
28 | /// | |
29 | //----------------------------------------------------------------------------- | |
30 | ||
31 | #include "AliMUONTrackReconstructorK.h" | |
32 | ||
33 | #include "AliMUONConstants.h" | |
34 | #include "AliMUONVCluster.h" | |
35 | #include "AliMUONVClusterServer.h" | |
36 | #include "AliMUONVClusterStore.h" | |
37 | #include "AliMUONTrack.h" | |
38 | #include "AliMUONTrackParam.h" | |
39 | #include "AliMUONTrackExtrap.h" | |
40 | ||
41 | #include "AliMpArea.h" | |
42 | ||
43 | #include "AliLog.h" | |
44 | ||
45 | #include <Riostream.h> | |
46 | #include <TMath.h> | |
47 | #include <TMatrixD.h> | |
48 | ||
49 | /// \cond CLASSIMP | |
50 | ClassImp(AliMUONTrackReconstructorK) // Class implementation in ROOT context | |
51 | /// \endcond | |
52 | ||
53 | //__________________________________________________________________________ | |
54 | AliMUONTrackReconstructorK::AliMUONTrackReconstructorK(AliMUONVClusterServer& clusterServer) | |
55 | : AliMUONVTrackReconstructor(clusterServer) | |
56 | { | |
57 | /// Constructor | |
58 | } | |
59 | ||
60 | //__________________________________________________________________________ | |
61 | AliMUONTrackReconstructorK::~AliMUONTrackReconstructorK() | |
62 | { | |
63 | /// Destructor | |
64 | } | |
65 | ||
66 | //__________________________________________________________________________ | |
67 | void AliMUONTrackReconstructorK::MakeTrackCandidates(AliMUONVClusterStore& clusterStore) | |
68 | { | |
69 | /// To make track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
70 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. | |
71 | /// Good candidates are made of at least three clusters if both station are requested (two otherwise). | |
72 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
73 | ||
74 | TClonesArray *segments; | |
75 | AliMUONTrack *track; | |
76 | Int_t iCandidate = 0; | |
77 | Bool_t clusterFound; | |
78 | ||
79 | AliDebug(1,"Enter MakeTrackCandidates"); | |
80 | ||
81 | // Unless we're doing combined tracking, we'll clusterize all stations at once | |
82 | Int_t firstChamber(0); | |
83 | Int_t lastChamber(9); | |
84 | ||
85 | if (AliMUONReconstructor::GetRecoParam()->CombineClusterTrackReco()) { | |
86 | // ... Here's the exception : ask the clustering to reconstruct | |
87 | // clusters *only* in station 4 and 5 for combined tracking | |
88 | firstChamber = 6; | |
89 | } | |
90 | ||
91 | for (Int_t i = firstChamber; i <= lastChamber; ++i ) | |
92 | { | |
93 | if (AliMUONReconstructor::GetRecoParam()->UseChamber(i)) fClusterServer.Clusterize(i, clusterStore, AliMpArea()); | |
94 | } | |
95 | ||
96 | // Loop over stations(1..) 5 and 4 and make track candidates | |
97 | for (Int_t istat=4; istat>=3; istat--) { | |
98 | ||
99 | // Make segments in the station | |
100 | segments = MakeSegmentsBetweenChambers(clusterStore, 2*istat, 2*istat+1); | |
101 | ||
102 | // Loop over segments | |
103 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) { | |
104 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
105 | ||
106 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
107 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg])); | |
108 | fNRecTracks++; | |
109 | ||
110 | // Look for compatible cluster(s) in the other station | |
111 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) | |
112 | clusterFound = FollowLinearTrackInStation(*track, clusterStore, 7-istat); | |
113 | else { | |
114 | // First recompute track parameters and covariances on station(1..) 5 using Kalman filter | |
115 | // (to make sure all tracks are treated in the same way) | |
116 | if (istat == 4) RetraceTrack(*track, kTRUE); | |
117 | clusterFound = FollowTrackInStation(*track, clusterStore, 7-istat); | |
118 | } | |
119 | ||
120 | // Remove track if no cluster found on a requested station | |
121 | if (!clusterFound) { | |
122 | if (AliMUONReconstructor::GetRecoParam()->RequestStation(7-istat)) { | |
123 | fRecTracksPtr->Remove(track); | |
124 | fNRecTracks--; | |
125 | } else if (istat == 3 && !AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) { | |
126 | // update track parameters and covariances using Kalman filter | |
127 | RetraceTrack(*track, kTRUE); | |
128 | } | |
129 | } | |
130 | ||
131 | } | |
132 | // delete the array of segments | |
133 | delete segments; | |
134 | } | |
135 | ||
136 | ||
137 | // Retrace tracks using Kalman filter and remove bad ones | |
138 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) { | |
139 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
140 | ||
141 | Int_t currentNRecTracks = fNRecTracks; | |
142 | for (Int_t iRecTrack = 0; iRecTrack < currentNRecTracks; iRecTrack++) { | |
143 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
144 | ||
145 | // Recompute track parameters and covariances using Kalman filter | |
146 | RetraceTrack(*track,kTRUE); | |
147 | ||
148 | // Remove the track if the normalized chi2 is too high | |
149 | if (track->GetNormalizedChi2() > AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
150 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking()) { | |
151 | fRecTracksPtr->Remove(track); | |
152 | fNRecTracks--; | |
153 | } | |
154 | ||
155 | } | |
156 | ||
157 | } | |
158 | ||
159 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
160 | ||
161 | // Keep all different tracks or only the best ones as required | |
162 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); | |
163 | else RemoveDoubleTracks(); | |
164 | ||
165 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
166 | ||
167 | } | |
168 | ||
169 | //__________________________________________________________________________ | |
170 | void AliMUONTrackReconstructorK::MakeMoreTrackCandidates(AliMUONVClusterStore& clusterStore) | |
171 | { | |
172 | /// To make extra track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
173 | /// clustering is supposed to be already done | |
174 | /// Start with segments made of 1 cluster in each of the stations 4 and 5 then follow track in remaining chambers. | |
175 | /// Good candidates are made of at least three clusters if both station are requested (two otherwise). | |
176 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
177 | ||
178 | TClonesArray *segments; | |
179 | AliMUONTrack *track; | |
180 | Int_t iCandidate = 0, iCurrentTrack, nCurrentTracks; | |
181 | Int_t initialNRecTracks = fNRecTracks; | |
182 | Bool_t clusterFound; | |
183 | ||
184 | AliDebug(1,"Enter MakeMoreTrackCandidates"); | |
185 | ||
186 | // Double loop over chambers in stations(1..) 4 and 5 to make track candidates | |
187 | for (Int_t ich1 = 6; ich1 <= 7; ich1++) { | |
188 | for (Int_t ich2 = 8; ich2 <= 9; ich2++) { | |
189 | ||
190 | // Make segments between ch1 and ch2 | |
191 | segments = MakeSegmentsBetweenChambers(clusterStore, ich1, ich2); | |
192 | ||
193 | // Loop over segments | |
194 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) { | |
195 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
196 | ||
197 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
198 | iCurrentTrack = fRecTracksPtr->GetLast()+1; | |
199 | track = new ((*fRecTracksPtr)[iCurrentTrack]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg])); | |
200 | fNRecTracks++; | |
201 | ||
202 | // Look for compatible cluster(s) in the second chamber of station 5 | |
203 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) | |
204 | clusterFound = FollowLinearTrackInChamber(*track, clusterStore, 17-ich2); | |
205 | else clusterFound = FollowTrackInChamber(*track, clusterStore, 17-ich2); | |
206 | ||
207 | // skip the original track in case it has been removed | |
208 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks() && clusterFound) iCurrentTrack++; | |
209 | ||
210 | // loop over every new tracks | |
211 | nCurrentTracks = fRecTracksPtr->GetLast()+1; | |
212 | while (iCurrentTrack < nCurrentTracks) { | |
213 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iCurrentTrack); | |
214 | ||
215 | // Look for compatible cluster(s) in the second chamber of station 4 | |
216 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) | |
217 | FollowLinearTrackInChamber(*track, clusterStore, 13-ich1); | |
218 | else FollowTrackInChamber(*track, clusterStore, 13-ich1); | |
219 | ||
220 | iCurrentTrack++; | |
221 | } | |
222 | ||
223 | } | |
224 | ||
225 | // delete the array of segments | |
226 | delete segments; | |
227 | } | |
228 | } | |
229 | ||
230 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
231 | ||
232 | // Retrace tracks using Kalman filter | |
233 | for (Int_t iRecTrack = initialNRecTracks; iRecTrack < fNRecTracks; iRecTrack++) { | |
234 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
235 | ||
236 | // Recompute track parameters and covariances using Kalman filter | |
237 | RetraceTrack(*track,kTRUE); | |
238 | ||
239 | // Remove the track if the normalized chi2 is too high | |
240 | // (only if the tracking has been done without magnetic field) | |
241 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast() && | |
242 | track->GetNormalizedChi2() > AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
243 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking()) { | |
244 | fRecTracksPtr->Remove(track); | |
245 | fNRecTracks--; | |
246 | } | |
247 | ||
248 | } | |
249 | ||
250 | // this is essential before checking tracks | |
251 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) fRecTracksPtr->Compress(); | |
252 | ||
253 | // Keep all different tracks or only the best ones as required | |
254 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); | |
255 | else RemoveDoubleTracks(); | |
256 | ||
257 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
258 | ||
259 | } | |
260 | ||
261 | //__________________________________________________________________________ | |
262 | void AliMUONTrackReconstructorK::RetraceTrack(AliMUONTrack &trackCandidate, Bool_t resetSeed) | |
263 | { | |
264 | /// Re-run the kalman filter from the most downstream cluster to the most uptream one | |
265 | AliDebug(1,"Enter RetraceTrack"); | |
266 | ||
267 | AliMUONTrackParam* lastTrackParam = (AliMUONTrackParam*) trackCandidate.GetTrackParamAtCluster()->Last(); | |
268 | ||
269 | // Reset the "seed" (= track parameters and their covariances at last cluster) if required | |
270 | if (resetSeed) { | |
271 | ||
272 | // parameters at last cluster | |
273 | AliMUONVCluster* cluster2 = lastTrackParam->GetClusterPtr(); | |
274 | Double_t x2 = cluster2->GetX(); | |
275 | Double_t y2 = cluster2->GetY(); | |
276 | Double_t z2 = cluster2->GetZ(); | |
277 | ||
278 | // parameters at last but one cluster | |
279 | AliMUONTrackParam* previousTrackParam = (AliMUONTrackParam*) trackCandidate.GetTrackParamAtCluster()->Before(lastTrackParam); | |
280 | AliMUONVCluster* cluster1 = previousTrackParam->GetClusterPtr(); | |
281 | // make sure it is on the previous chamber (can have 2 clusters in the same chamber after "ComplementTrack") | |
282 | if (cluster2->GetChamberId() == cluster1->GetChamberId()) { | |
283 | previousTrackParam = (AliMUONTrackParam*) trackCandidate.GetTrackParamAtCluster()->Before(previousTrackParam); | |
284 | cluster1 = previousTrackParam->GetClusterPtr(); | |
285 | } | |
286 | Double_t x1 = cluster1->GetX(); | |
287 | Double_t y1 = cluster1->GetY(); | |
288 | Double_t z1 = cluster1->GetZ(); | |
289 | ||
290 | // reset track parameters | |
291 | Double_t dZ = z1 - z2; | |
292 | lastTrackParam->SetNonBendingCoor(x2); | |
293 | lastTrackParam->SetBendingCoor(y2); | |
294 | lastTrackParam->SetZ(z2); | |
295 | lastTrackParam->SetNonBendingSlope((x1 - x2) / dZ); | |
296 | lastTrackParam->SetBendingSlope((y1 - y2) / dZ); | |
297 | Double_t bendingImpact = y2 - z2 * lastTrackParam->GetBendingSlope(); | |
298 | Double_t inverseBendingMomentum = 1. / AliMUONTrackExtrap::GetBendingMomentumFromImpactParam(bendingImpact); | |
299 | lastTrackParam->SetInverseBendingMomentum(inverseBendingMomentum); | |
300 | ||
301 | // => Reset track parameter covariances at last cluster (as if the other clusters did not exist) | |
302 | TMatrixD lastParamCov(5,5); | |
303 | lastParamCov.Zero(); | |
304 | // Non bending plane | |
305 | lastParamCov(0,0) = cluster2->GetErrX2(); | |
306 | lastParamCov(1,1) = 100. * ( cluster1->GetErrX2() + cluster2->GetErrX2() ) / dZ / dZ; | |
307 | // Bending plane | |
308 | lastParamCov(2,2) = cluster2->GetErrY2(); | |
309 | lastParamCov(3,3) = 100. * ( cluster1->GetErrY2() + cluster2->GetErrY2() ) / dZ / dZ; | |
310 | // Inverse bending momentum (vertex resolution + bending slope resolution + 10% error on dipole parameters+field) | |
311 | lastParamCov(4,4) = ((AliMUONReconstructor::GetRecoParam()->GetBendingVertexDispersion() * | |
312 | AliMUONReconstructor::GetRecoParam()->GetBendingVertexDispersion() + | |
313 | (z1 * z1 * cluster2->GetErrY2() + z2 * z2 * cluster1->GetErrY2()) / dZ / dZ) / | |
314 | bendingImpact / bendingImpact + 0.1 * 0.1) * inverseBendingMomentum * inverseBendingMomentum; | |
315 | lastTrackParam->SetCovariances(lastParamCov); | |
316 | ||
317 | // Reset the track chi2 | |
318 | lastTrackParam->SetTrackChi2(0.); | |
319 | ||
320 | } | |
321 | ||
322 | // Redo the tracking | |
323 | RetracePartialTrack(trackCandidate, lastTrackParam); | |
324 | ||
325 | } | |
326 | ||
327 | //__________________________________________________________________________ | |
328 | void AliMUONTrackReconstructorK::RetracePartialTrack(AliMUONTrack &trackCandidate, const AliMUONTrackParam* startingTrackParam) | |
329 | { | |
330 | /// Re-run the kalman filter from the cluster attached to startingTrackParam to the most uptream cluster | |
331 | AliDebug(1,"Enter RetracePartialTrack"); | |
332 | ||
333 | // Printout for debuging | |
334 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
335 | cout << "RetracePartialTrack: track chi2 before re-tracking: " << trackCandidate.GetGlobalChi2() << endl; | |
336 | } | |
337 | ||
338 | // Reset the track chi2 | |
339 | trackCandidate.SetGlobalChi2(startingTrackParam->GetTrackChi2()); | |
340 | ||
341 | // loop over attached clusters until the first one and recompute track parameters and covariances using kalman filter | |
342 | Int_t expectedChamber = startingTrackParam->GetClusterPtr()->GetChamberId() - 1; | |
343 | Int_t currentChamber; | |
344 | Double_t addChi2TrackAtCluster; | |
345 | AliMUONTrackParam* trackParamAtCluster = (AliMUONTrackParam*) trackCandidate.GetTrackParamAtCluster()->Before(startingTrackParam); | |
346 | while (trackParamAtCluster) { | |
347 | ||
348 | // reset track parameters and their covariances | |
349 | trackParamAtCluster->SetParameters(startingTrackParam->GetParameters()); | |
350 | trackParamAtCluster->SetZ(startingTrackParam->GetZ()); | |
351 | trackParamAtCluster->SetCovariances(startingTrackParam->GetCovariances()); | |
352 | ||
353 | // add MCS effect | |
354 | AliMUONTrackExtrap::AddMCSEffect(trackParamAtCluster,AliMUONConstants::ChamberThicknessInX0(),1.); | |
355 | ||
356 | // reset propagator for smoother | |
357 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) trackParamAtCluster->ResetPropagator(); | |
358 | ||
359 | // add MCS in missing chambers if any | |
360 | currentChamber = trackParamAtCluster->GetClusterPtr()->GetChamberId(); | |
361 | while (currentChamber < expectedChamber) { | |
362 | // extrapolation to the missing chamber (update the propagator) | |
363 | AliMUONTrackExtrap::ExtrapToZCov(trackParamAtCluster, AliMUONConstants::DefaultChamberZ(expectedChamber), | |
364 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
365 | // add MCS effect | |
366 | AliMUONTrackExtrap::AddMCSEffect(trackParamAtCluster,AliMUONConstants::ChamberThicknessInX0(),1.); | |
367 | expectedChamber--; | |
368 | } | |
369 | ||
370 | // extrapolation to the plane of the cluster attached to the current trackParamAtCluster (update the propagator) | |
371 | AliMUONTrackExtrap::ExtrapToZCov(trackParamAtCluster, trackParamAtCluster->GetClusterPtr()->GetZ(), | |
372 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
373 | ||
374 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) { | |
375 | // save extrapolated parameters for smoother | |
376 | trackParamAtCluster->SetExtrapParameters(trackParamAtCluster->GetParameters()); | |
377 | ||
378 | // save extrapolated covariance matrix for smoother | |
379 | trackParamAtCluster->SetExtrapCovariances(trackParamAtCluster->GetCovariances()); | |
380 | } | |
381 | ||
382 | // Compute new track parameters using kalman filter | |
383 | addChi2TrackAtCluster = RunKalmanFilter(*trackParamAtCluster); | |
384 | ||
385 | // Update the track chi2 | |
386 | trackCandidate.SetGlobalChi2(trackCandidate.GetGlobalChi2() + addChi2TrackAtCluster); | |
387 | trackParamAtCluster->SetTrackChi2(trackCandidate.GetGlobalChi2()); | |
388 | ||
389 | // prepare next step | |
390 | expectedChamber = currentChamber - 1; | |
391 | startingTrackParam = trackParamAtCluster; | |
392 | trackParamAtCluster = (AliMUONTrackParam*) (trackCandidate.GetTrackParamAtCluster()->Before(startingTrackParam)); | |
393 | } | |
394 | ||
395 | // Printout for debuging | |
396 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
397 | cout << "RetracePartialTrack: track chi2 after re-tracking: " << trackCandidate.GetGlobalChi2() << endl; | |
398 | } | |
399 | ||
400 | } | |
401 | ||
402 | //__________________________________________________________________________ | |
403 | void AliMUONTrackReconstructorK::FollowTracks(AliMUONVClusterStore& clusterStore) | |
404 | { | |
405 | /// Follow tracks in stations(1..) 3, 2 and 1 | |
406 | AliDebug(1,"Enter FollowTracks"); | |
407 | ||
408 | AliMUONTrack *track; | |
409 | Int_t currentNRecTracks; | |
410 | ||
411 | for (Int_t station = 2; station >= 0; station--) { | |
412 | ||
413 | // Save the actual number of reconstructed track in case of | |
414 | // tracks are added or suppressed during the tracking procedure | |
415 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
416 | currentNRecTracks = fNRecTracks; | |
417 | ||
418 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { | |
419 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); | |
420 | ||
421 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
422 | ||
423 | // Look for compatible cluster(s) in station(0..) "station" | |
424 | if (!FollowTrackInStation(*track, clusterStore, station)) { | |
425 | ||
426 | // Try to recover track if required | |
427 | if (AliMUONReconstructor::GetRecoParam()->RecoverTracks()) { | |
428 | ||
429 | // work on a copy of the track if this station is not required | |
430 | // to keep the case where no cluster is reconstructed as a possible candidate | |
431 | if (!AliMUONReconstructor::GetRecoParam()->RequestStation(station)) { | |
432 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*track); | |
433 | fNRecTracks++; | |
434 | } | |
435 | ||
436 | // try to recover | |
437 | if (!RecoverTrack(*track, clusterStore, station)) { | |
438 | // remove track if no cluster found | |
439 | fRecTracksPtr->Remove(track); | |
440 | fNRecTracks--; | |
441 | } | |
442 | ||
443 | } else if (AliMUONReconstructor::GetRecoParam()->RequestStation(station)) { | |
444 | // remove track if no cluster found | |
445 | fRecTracksPtr->Remove(track); | |
446 | fNRecTracks--; | |
447 | } | |
448 | ||
449 | } | |
450 | ||
451 | } | |
452 | ||
453 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
454 | ||
455 | // Keep only the best tracks if required | |
456 | if (!AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); | |
457 | ||
458 | } | |
459 | ||
460 | } | |
461 | ||
462 | //__________________________________________________________________________ | |
463 | Bool_t AliMUONTrackReconstructorK::FollowTrackInChamber(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextChamber) | |
464 | { | |
465 | /// Follow trackCandidate in chamber(0..) nextChamber and search for compatible cluster(s) | |
466 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
467 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
468 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
469 | /// Remove the obsolete "trackCandidate" at the end. | |
470 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
471 | /// return kTRUE if new cluster(s) have been found (otherwise return kFALSE) | |
472 | AliDebug(1,Form("Enter FollowTrackInChamber(1..) %d", nextChamber+1)); | |
473 | ||
474 | Double_t bendingMomentum; | |
475 | Double_t chi2OfCluster; | |
476 | Double_t maxChi2OfCluster = 2. * AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
477 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
478 | Double_t addChi2TrackAtCluster; | |
479 | Double_t bestAddChi2TrackAtCluster = 1.e10; | |
480 | Bool_t foundOneCluster = kFALSE; | |
481 | AliMUONTrack *newTrack = 0x0; | |
482 | AliMUONVCluster *cluster; | |
483 | AliMUONTrackParam extrapTrackParamAtCh; | |
484 | AliMUONTrackParam extrapTrackParamAtCluster; | |
485 | AliMUONTrackParam bestTrackParamAtCluster; | |
486 | ||
487 | // Get track parameters according to the propagation direction | |
488 | if (nextChamber > 7) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
489 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
490 | ||
491 | // Printout for debuging | |
492 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
493 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
494 | extrapTrackParamAtCh.GetParameters().Print(); | |
495 | extrapTrackParamAtCh.GetCovariances().Print(); | |
496 | } | |
497 | ||
498 | // Add MCS effect | |
499 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
500 | ||
501 | // reset propagator for smoother | |
502 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) extrapTrackParamAtCh.ResetPropagator(); | |
503 | ||
504 | // Add MCS in the missing chamber(s) if any | |
505 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
506 | while (currentChamber > nextChamber + 1) { | |
507 | // extrapolation to the missing chamber | |
508 | currentChamber--; | |
509 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber), | |
510 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
511 | // add MCS effect | |
512 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
513 | } | |
514 | ||
515 | //Extrapolate trackCandidate to chamber | |
516 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(nextChamber), | |
517 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
518 | ||
519 | // Printout for debuging | |
520 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
521 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(nextChamber)<<":"<<endl; | |
522 | extrapTrackParamAtCh.GetParameters().Print(); | |
523 | extrapTrackParamAtCh.GetCovariances().Print(); | |
524 | } | |
525 | ||
526 | // Printout for debuging | |
527 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
528 | cout << "FollowTrackInChamber: look for clusters in chamber(1..): " << nextChamber+1 << endl; | |
529 | } | |
530 | ||
531 | // Ask the clustering to reconstruct new clusters around the track position in the current chamber | |
532 | // except for station 4 and 5 that are already entirely clusterized | |
533 | if (AliMUONReconstructor::GetRecoParam()->CombineClusterTrackReco()) { | |
534 | if (nextChamber < 6) AskForNewClustersInChamber(extrapTrackParamAtCh, clusterStore, nextChamber); | |
535 | } | |
536 | ||
537 | // Create iterators to loop over clusters in both chambers | |
538 | TIter next(clusterStore.CreateChamberIterator(nextChamber,nextChamber)); | |
539 | ||
540 | // look for candidates in chamber | |
541 | while ( ( cluster = static_cast<AliMUONVCluster*>(next()) ) ) { | |
542 | ||
543 | // try to add the current cluster fast | |
544 | if (!TryOneClusterFast(extrapTrackParamAtCh, cluster)) continue; | |
545 | ||
546 | // try to add the current cluster accuratly | |
547 | chi2OfCluster = TryOneCluster(extrapTrackParamAtCh, cluster, extrapTrackParamAtCluster, | |
548 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
549 | ||
550 | // if good chi2 then consider to add cluster | |
551 | if (chi2OfCluster < maxChi2OfCluster) { | |
552 | foundOneCluster = kTRUE; | |
553 | ||
554 | // Printout for debuging | |
555 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
556 | cout << "FollowTrackInChamber: found one cluster in chamber(1..): " << nextChamber+1 | |
557 | << " (Chi2 = " << chi2OfCluster << ")" << endl; | |
558 | cluster->Print(); | |
559 | } | |
560 | ||
561 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) { | |
562 | // save extrapolated parameters for smoother | |
563 | extrapTrackParamAtCluster.SetExtrapParameters(extrapTrackParamAtCluster.GetParameters()); | |
564 | ||
565 | // save extrapolated covariance matrix for smoother | |
566 | extrapTrackParamAtCluster.SetExtrapCovariances(extrapTrackParamAtCluster.GetCovariances()); | |
567 | } | |
568 | ||
569 | // Compute new track parameters including new cluster using kalman filter | |
570 | addChi2TrackAtCluster = RunKalmanFilter(extrapTrackParamAtCluster); | |
571 | ||
572 | // skip track with absolute bending momentum out of limits | |
573 | bendingMomentum = TMath::Abs(1. / extrapTrackParamAtCluster.GetInverseBendingMomentum()); | |
574 | if (bendingMomentum < AliMUONReconstructor::GetRecoParam()->GetMinBendingMomentum() || | |
575 | bendingMomentum > AliMUONReconstructor::GetRecoParam()->GetMaxBendingMomentum()) continue; | |
576 | ||
577 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
578 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
579 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
580 | UpdateTrack(*newTrack,extrapTrackParamAtCluster,addChi2TrackAtCluster); | |
581 | fNRecTracks++; | |
582 | ||
583 | // Printout for debuging | |
584 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
585 | cout << "FollowTrackInChamber: added one cluster in chamber(1..): " << nextChamber+1 << endl; | |
586 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
587 | } | |
588 | ||
589 | } else if (addChi2TrackAtCluster < bestAddChi2TrackAtCluster) { | |
590 | // keep track of the best cluster | |
591 | bestAddChi2TrackAtCluster = addChi2TrackAtCluster; | |
592 | bestTrackParamAtCluster = extrapTrackParamAtCluster; | |
593 | } | |
594 | ||
595 | } | |
596 | ||
597 | } | |
598 | ||
599 | // fill out the best track if required else clean up the fRecTracksPtr array | |
600 | if (!AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
601 | if (foundOneCluster) { | |
602 | UpdateTrack(trackCandidate,bestTrackParamAtCluster,bestAddChi2TrackAtCluster); | |
603 | ||
604 | // Printout for debuging | |
605 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
606 | cout << "FollowTrackInChamber: added the best cluster in chamber(1..): " << bestTrackParamAtCluster.GetClusterPtr()->GetChamberId()+1 << endl; | |
607 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
608 | } | |
609 | ||
610 | } else return kFALSE; | |
611 | ||
612 | } else if (foundOneCluster) { | |
613 | ||
614 | // remove obsolete track | |
615 | fRecTracksPtr->Remove(&trackCandidate); | |
616 | fNRecTracks--; | |
617 | ||
618 | } else return kFALSE; | |
619 | ||
620 | return kTRUE; | |
621 | ||
622 | } | |
623 | ||
624 | //__________________________________________________________________________ | |
625 | Bool_t AliMUONTrackReconstructorK::FollowTrackInStation(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) | |
626 | { | |
627 | /// Follow trackCandidate in station(0..) nextStation and search for compatible cluster(s) | |
628 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
629 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
630 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
631 | /// Remove the obsolete "trackCandidate" at the end. | |
632 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
633 | /// return kTRUE if new cluster(s) have been found (otherwise return kFALSE) | |
634 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); | |
635 | ||
636 | // Order the chamber according to the propagation direction (tracking starts with chamber 2): | |
637 | // - nextStation == station(1...) 5 => forward propagation | |
638 | // - nextStation < station(1...) 5 => backward propagation | |
639 | Int_t ch1, ch2; | |
640 | if (nextStation==4) { | |
641 | ch1 = 2*nextStation+1; | |
642 | ch2 = 2*nextStation; | |
643 | } else { | |
644 | ch1 = 2*nextStation; | |
645 | ch2 = 2*nextStation+1; | |
646 | } | |
647 | ||
648 | Double_t bendingMomentum; | |
649 | Double_t chi2OfCluster; | |
650 | Double_t maxChi2OfCluster = 2. * AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
651 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
652 | Double_t addChi2TrackAtCluster1; | |
653 | Double_t addChi2TrackAtCluster2; | |
654 | Double_t bestAddChi2TrackAtCluster1 = 1.e10; | |
655 | Double_t bestAddChi2TrackAtCluster2 = 1.e10; | |
656 | Bool_t foundOneCluster = kFALSE; | |
657 | Bool_t foundTwoClusters = kFALSE; | |
658 | AliMUONTrack *newTrack = 0x0; | |
659 | AliMUONVCluster *clusterCh1, *clusterCh2; | |
660 | AliMUONTrackParam extrapTrackParam; | |
661 | AliMUONTrackParam extrapTrackParamAtCh; | |
662 | AliMUONTrackParam extrapTrackParamAtCluster1; | |
663 | AliMUONTrackParam extrapTrackParamAtCluster2; | |
664 | AliMUONTrackParam bestTrackParamAtCluster1; | |
665 | AliMUONTrackParam bestTrackParamAtCluster2; | |
666 | ||
667 | Int_t nClusters = clusterStore.GetSize(); | |
668 | Bool_t *clusterCh1Used = new Bool_t[nClusters]; | |
669 | for (Int_t i = 0; i < nClusters; i++) clusterCh1Used[i] = kFALSE; | |
670 | Int_t iCluster1; | |
671 | ||
672 | // Get track parameters according to the propagation direction | |
673 | ||
674 | if (nextStation==4) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
675 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
676 | ||
677 | // Printout for debuging | |
678 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
679 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
680 | extrapTrackParamAtCh.GetParameters().Print(); | |
681 | extrapTrackParamAtCh.GetCovariances().Print(); | |
682 | } | |
683 | ||
684 | // Add MCS effect | |
685 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
686 | ||
687 | // reset propagator for smoother | |
688 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) extrapTrackParamAtCh.ResetPropagator(); | |
689 | ||
690 | // Add MCS in the missing chamber(s) if any | |
691 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
692 | while (ch1 < ch2 && currentChamber > ch2 + 1) { | |
693 | // extrapolation to the missing chamber | |
694 | currentChamber--; | |
695 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber), | |
696 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
697 | // add MCS effect | |
698 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
699 | } | |
700 | ||
701 | //Extrapolate trackCandidate to chamber "ch2" | |
702 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2), | |
703 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
704 | ||
705 | // Printout for debuging | |
706 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
707 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch2)<<":"<<endl; | |
708 | extrapTrackParamAtCh.GetParameters().Print(); | |
709 | extrapTrackParamAtCh.GetCovariances().Print(); | |
710 | } | |
711 | ||
712 | // Printout for debuging | |
713 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
714 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << ch2+1 << endl; | |
715 | } | |
716 | ||
717 | // Ask the clustering to reconstruct new clusters around the track position in the current station | |
718 | // except for station 4 and 5 that are already entirely clusterized | |
719 | if (AliMUONReconstructor::GetRecoParam()->CombineClusterTrackReco()) { | |
720 | if (nextStation < 3) AskForNewClustersInStation(extrapTrackParamAtCh, clusterStore, nextStation); | |
721 | } | |
722 | ||
723 | // Create iterators to loop over clusters in both chambers | |
724 | TIter nextInCh1(clusterStore.CreateChamberIterator(ch1,ch1)); | |
725 | TIter nextInCh2(clusterStore.CreateChamberIterator(ch2,ch2)); | |
726 | ||
727 | // look for candidates in chamber 2 | |
728 | while ( ( clusterCh2 = static_cast<AliMUONVCluster*>(nextInCh2()) ) ) { | |
729 | ||
730 | // try to add the current cluster fast | |
731 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh2)) continue; | |
732 | ||
733 | // try to add the current cluster accuratly | |
734 | chi2OfCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh2, extrapTrackParamAtCluster2, | |
735 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
736 | ||
737 | // if good chi2 then try to attach a cluster in the other chamber too | |
738 | if (chi2OfCluster < maxChi2OfCluster) { | |
739 | Bool_t foundSecondCluster = kFALSE; | |
740 | ||
741 | // Printout for debuging | |
742 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
743 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch2+1 | |
744 | << " (Chi2 = " << chi2OfCluster << ")" << endl; | |
745 | clusterCh2->Print(); | |
746 | cout << " look for second clusters in chamber(1..): " << ch1+1 << " ..." << endl; | |
747 | } | |
748 | ||
749 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) { | |
750 | // save extrapolated parameters for smoother | |
751 | extrapTrackParamAtCluster2.SetExtrapParameters(extrapTrackParamAtCluster2.GetParameters()); | |
752 | ||
753 | // save extrapolated covariance matrix for smoother | |
754 | extrapTrackParamAtCluster2.SetExtrapCovariances(extrapTrackParamAtCluster2.GetCovariances()); | |
755 | } | |
756 | ||
757 | // Compute new track parameters including "clusterCh2" using kalman filter | |
758 | addChi2TrackAtCluster2 = RunKalmanFilter(extrapTrackParamAtCluster2); | |
759 | ||
760 | // skip track with absolute bending momentum out of limits | |
761 | bendingMomentum = TMath::Abs(1. / extrapTrackParamAtCluster2.GetInverseBendingMomentum()); | |
762 | if (bendingMomentum < AliMUONReconstructor::GetRecoParam()->GetMinBendingMomentum() || | |
763 | bendingMomentum > AliMUONReconstructor::GetRecoParam()->GetMaxBendingMomentum()) continue; | |
764 | ||
765 | // copy new track parameters for next step | |
766 | extrapTrackParam = extrapTrackParamAtCluster2; | |
767 | ||
768 | // add MCS effect | |
769 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParam,AliMUONConstants::ChamberThicknessInX0(),1.); | |
770 | ||
771 | // reset propagator for smoother | |
772 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) extrapTrackParam.ResetPropagator(); | |
773 | ||
774 | //Extrapolate track parameters to chamber "ch1" | |
775 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParam, AliMUONConstants::DefaultChamberZ(ch1), | |
776 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
777 | ||
778 | // reset cluster iterator of chamber 1 | |
779 | nextInCh1.Reset(); | |
780 | iCluster1 = -1; | |
781 | ||
782 | // look for second candidates in chamber 1 | |
783 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
784 | iCluster1++; | |
785 | ||
786 | // try to add the current cluster fast | |
787 | if (!TryOneClusterFast(extrapTrackParam, clusterCh1)) continue; | |
788 | ||
789 | // try to add the current cluster accuratly | |
790 | chi2OfCluster = TryOneCluster(extrapTrackParam, clusterCh1, extrapTrackParamAtCluster1, | |
791 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
792 | ||
793 | // if good chi2 then consider to add the 2 clusters to the "trackCandidate" | |
794 | if (chi2OfCluster < maxChi2OfCluster) { | |
795 | foundSecondCluster = kTRUE; | |
796 | foundTwoClusters = kTRUE; | |
797 | ||
798 | // Printout for debuging | |
799 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
800 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 | |
801 | << " (Chi2 = " << chi2OfCluster << ")" << endl; | |
802 | clusterCh1->Print(); | |
803 | } | |
804 | ||
805 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) { | |
806 | // save extrapolated parameters for smoother | |
807 | extrapTrackParamAtCluster1.SetExtrapParameters(extrapTrackParamAtCluster1.GetParameters()); | |
808 | ||
809 | // save extrapolated covariance matrix for smoother | |
810 | extrapTrackParamAtCluster1.SetExtrapCovariances(extrapTrackParamAtCluster1.GetCovariances()); | |
811 | } | |
812 | ||
813 | // Compute new track parameters including "clusterCh1" using kalman filter | |
814 | addChi2TrackAtCluster1 = RunKalmanFilter(extrapTrackParamAtCluster1); | |
815 | ||
816 | // skip track with absolute bending momentum out of limits | |
817 | bendingMomentum = TMath::Abs(1. / extrapTrackParamAtCluster1.GetInverseBendingMomentum()); | |
818 | if (bendingMomentum < AliMUONReconstructor::GetRecoParam()->GetMinBendingMomentum() || | |
819 | bendingMomentum > AliMUONReconstructor::GetRecoParam()->GetMaxBendingMomentum()) continue; | |
820 | ||
821 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
822 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new clusters | |
823 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
824 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,extrapTrackParamAtCluster2,addChi2TrackAtCluster1,addChi2TrackAtCluster2); | |
825 | fNRecTracks++; | |
826 | ||
827 | // if we are arrived on station(1..) 5, recompute track parameters and covariances starting from this station | |
828 | // (going in the right direction) | |
829 | if (nextStation == 4) RetraceTrack(*newTrack,kTRUE); | |
830 | ||
831 | // Tag clusterCh1 as used | |
832 | clusterCh1Used[iCluster1] = kTRUE; | |
833 | ||
834 | // Printout for debuging | |
835 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
836 | cout << "FollowTrackInStation: added two clusters in station(1..): " << nextStation+1 << endl; | |
837 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
838 | } | |
839 | ||
840 | } else if (addChi2TrackAtCluster1+addChi2TrackAtCluster2 < bestAddChi2TrackAtCluster1+bestAddChi2TrackAtCluster2) { | |
841 | // keep track of the best couple of clusters | |
842 | bestAddChi2TrackAtCluster1 = addChi2TrackAtCluster1; | |
843 | bestAddChi2TrackAtCluster2 = addChi2TrackAtCluster2; | |
844 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
845 | bestTrackParamAtCluster2 = extrapTrackParamAtCluster2; | |
846 | } | |
847 | ||
848 | } | |
849 | ||
850 | } | |
851 | ||
852 | // if no clusterCh1 found then consider to add clusterCh2 only | |
853 | if (!foundSecondCluster) { | |
854 | foundOneCluster = kTRUE; | |
855 | ||
856 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
857 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
858 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
859 | UpdateTrack(*newTrack,extrapTrackParamAtCluster2,addChi2TrackAtCluster2); | |
860 | fNRecTracks++; | |
861 | ||
862 | // if we are arrived on station(1..) 5, recompute track parameters and covariances starting from this station | |
863 | // (going in the right direction) | |
864 | if (nextStation == 4) RetraceTrack(*newTrack,kTRUE); | |
865 | ||
866 | // Printout for debuging | |
867 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
868 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch2+1 << endl; | |
869 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
870 | } | |
871 | ||
872 | } else if (!foundTwoClusters && addChi2TrackAtCluster2 < bestAddChi2TrackAtCluster1) { | |
873 | // keep track of the best single cluster except if a couple of clusters has already been found | |
874 | bestAddChi2TrackAtCluster1 = addChi2TrackAtCluster2; | |
875 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster2; | |
876 | } | |
877 | ||
878 | } | |
879 | ||
880 | } | |
881 | ||
882 | } | |
883 | ||
884 | // look for candidates in chamber 1 not already attached to a track | |
885 | // if we want to keep all possible tracks or if no good couple of clusters has been found | |
886 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks() || !foundTwoClusters) { | |
887 | ||
888 | // add MCS effect for next step | |
889 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
890 | ||
891 | //Extrapolate trackCandidate to chamber "ch1" | |
892 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch1), | |
893 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
894 | ||
895 | // Printout for debuging | |
896 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
897 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch1)<<":"<<endl; | |
898 | extrapTrackParamAtCh.GetParameters().Print(); | |
899 | extrapTrackParamAtCh.GetCovariances().Print(); | |
900 | } | |
901 | ||
902 | // Printout for debuging | |
903 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
904 | cout << "FollowTrackInStation: look for single clusters in chamber(1..): " << ch1+1 << endl; | |
905 | } | |
906 | ||
907 | // reset cluster iterator of chamber 1 | |
908 | nextInCh1.Reset(); | |
909 | iCluster1 = -1; | |
910 | ||
911 | // look for second candidates in chamber 1 | |
912 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
913 | iCluster1++; | |
914 | ||
915 | if (clusterCh1Used[iCluster1]) continue; // Skip clusters already used | |
916 | ||
917 | // try to add the current cluster fast | |
918 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh1)) continue; | |
919 | ||
920 | // try to add the current cluster accuratly | |
921 | chi2OfCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh1, extrapTrackParamAtCluster1, | |
922 | AliMUONReconstructor::GetRecoParam()->UseSmoother()); | |
923 | ||
924 | // if good chi2 then consider to add clusterCh1 | |
925 | // We do not try to attach a cluster in the other chamber too since it has already been done above | |
926 | if (chi2OfCluster < maxChi2OfCluster) { | |
927 | foundOneCluster = kTRUE; | |
928 | ||
929 | // Printout for debuging | |
930 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
931 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 | |
932 | << " (Chi2 = " << chi2OfCluster << ")" << endl; | |
933 | clusterCh1->Print(); | |
934 | } | |
935 | ||
936 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) { | |
937 | // save extrapolated parameters for smoother | |
938 | extrapTrackParamAtCluster1.SetExtrapParameters(extrapTrackParamAtCluster1.GetParameters()); | |
939 | ||
940 | // save extrapolated covariance matrix for smoother | |
941 | extrapTrackParamAtCluster1.SetExtrapCovariances(extrapTrackParamAtCluster1.GetCovariances()); | |
942 | } | |
943 | ||
944 | // Compute new track parameters including "clusterCh1" using kalman filter | |
945 | addChi2TrackAtCluster1 = RunKalmanFilter(extrapTrackParamAtCluster1); | |
946 | ||
947 | // skip track with absolute bending momentum out of limits | |
948 | bendingMomentum = TMath::Abs(1. / extrapTrackParamAtCluster1.GetInverseBendingMomentum()); | |
949 | if (bendingMomentum < AliMUONReconstructor::GetRecoParam()->GetMinBendingMomentum() || | |
950 | bendingMomentum > AliMUONReconstructor::GetRecoParam()->GetMaxBendingMomentum()) continue; | |
951 | ||
952 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
953 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster | |
954 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
955 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,addChi2TrackAtCluster1); | |
956 | fNRecTracks++; | |
957 | ||
958 | // if we are arrived on station(1..) 5, recompute track parameters and covariances starting from this station | |
959 | // (going in the right direction) | |
960 | if (nextStation == 4) RetraceTrack(*newTrack,kTRUE); | |
961 | ||
962 | // Printout for debuging | |
963 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
964 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch1+1 << endl; | |
965 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
966 | } | |
967 | ||
968 | } else if (addChi2TrackAtCluster1 < bestAddChi2TrackAtCluster1) { | |
969 | // keep track of the best single cluster except if a couple of clusters has already been found | |
970 | bestAddChi2TrackAtCluster1 = addChi2TrackAtCluster1; | |
971 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
972 | } | |
973 | ||
974 | } | |
975 | ||
976 | } | |
977 | ||
978 | } | |
979 | ||
980 | // fill out the best track if required else clean up the fRecTracksPtr array | |
981 | if (!AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { | |
982 | if (foundTwoClusters) { | |
983 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestTrackParamAtCluster2,bestAddChi2TrackAtCluster1,bestAddChi2TrackAtCluster2); | |
984 | ||
985 | // if we are arrived on station(1..) 5, recompute track parameters and covariances starting from this station | |
986 | // (going in the right direction) | |
987 | if (nextStation == 4) RetraceTrack(trackCandidate,kTRUE); | |
988 | ||
989 | // Printout for debuging | |
990 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
991 | cout << "FollowTrackInStation: added the two best clusters in station(1..): " << nextStation+1 << endl; | |
992 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
993 | } | |
994 | ||
995 | } else if (foundOneCluster) { | |
996 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestAddChi2TrackAtCluster1); | |
997 | ||
998 | // if we are arrived on station(1..) 5, recompute track parameters and covariances starting from this station | |
999 | // (going in the right direction) | |
1000 | if (nextStation == 4) RetraceTrack(trackCandidate,kTRUE); | |
1001 | ||
1002 | // Printout for debuging | |
1003 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1004 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster1.GetClusterPtr()->GetChamberId()+1 << endl; | |
1005 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
1006 | } | |
1007 | ||
1008 | } else { | |
1009 | delete [] clusterCh1Used; | |
1010 | return kFALSE; | |
1011 | } | |
1012 | ||
1013 | } else if (foundOneCluster || foundTwoClusters) { | |
1014 | ||
1015 | // remove obsolete track | |
1016 | fRecTracksPtr->Remove(&trackCandidate); | |
1017 | fNRecTracks--; | |
1018 | ||
1019 | } else { | |
1020 | delete [] clusterCh1Used; | |
1021 | return kFALSE; | |
1022 | } | |
1023 | ||
1024 | delete [] clusterCh1Used; | |
1025 | return kTRUE; | |
1026 | ||
1027 | } | |
1028 | ||
1029 | //__________________________________________________________________________ | |
1030 | Double_t AliMUONTrackReconstructorK::RunKalmanFilter(AliMUONTrackParam &trackParamAtCluster) | |
1031 | { | |
1032 | /// Compute new track parameters and their covariances including new cluster using kalman filter | |
1033 | /// return the additional track chi2 | |
1034 | AliDebug(1,"Enter RunKalmanFilter"); | |
1035 | ||
1036 | // Get actual track parameters (p) | |
1037 | TMatrixD param(trackParamAtCluster.GetParameters()); | |
1038 | ||
1039 | // Get new cluster parameters (m) | |
1040 | AliMUONVCluster *cluster = trackParamAtCluster.GetClusterPtr(); | |
1041 | TMatrixD clusterParam(5,1); | |
1042 | clusterParam.Zero(); | |
1043 | clusterParam(0,0) = cluster->GetX(); | |
1044 | clusterParam(2,0) = cluster->GetY(); | |
1045 | ||
1046 | // Compute the actual parameter weight (W) | |
1047 | TMatrixD paramWeight(trackParamAtCluster.GetCovariances()); | |
1048 | if (paramWeight.Determinant() != 0) { | |
1049 | paramWeight.Invert(); | |
1050 | } else { | |
1051 | AliWarning(" Determinant = 0"); | |
1052 | return 1.e10; | |
1053 | } | |
1054 | ||
1055 | // Compute the new cluster weight (U) | |
1056 | TMatrixD clusterWeight(5,5); | |
1057 | clusterWeight.Zero(); | |
1058 | clusterWeight(0,0) = 1. / cluster->GetErrX2(); | |
1059 | clusterWeight(2,2) = 1. / cluster->GetErrY2(); | |
1060 | ||
1061 | // Compute the new parameters covariance matrix ( (W+U)^-1 ) | |
1062 | TMatrixD newParamCov(paramWeight,TMatrixD::kPlus,clusterWeight); | |
1063 | if (newParamCov.Determinant() != 0) { | |
1064 | newParamCov.Invert(); | |
1065 | } else { | |
1066 | AliWarning(" Determinant = 0"); | |
1067 | return 1.e10; | |
1068 | } | |
1069 | ||
1070 | // Save the new parameters covariance matrix | |
1071 | trackParamAtCluster.SetCovariances(newParamCov); | |
1072 | ||
1073 | // Compute the new parameters (p' = ((W+U)^-1)U(m-p) + p) | |
1074 | TMatrixD tmp(clusterParam,TMatrixD::kMinus,param); | |
1075 | TMatrixD tmp2(clusterWeight,TMatrixD::kMult,tmp); // U(m-p) | |
1076 | TMatrixD newParam(newParamCov,TMatrixD::kMult,tmp2); // ((W+U)^-1)U(m-p) | |
1077 | newParam += param; // ((W+U)^-1)U(m-p) + p | |
1078 | ||
1079 | // Save the new parameters | |
1080 | trackParamAtCluster.SetParameters(newParam); | |
1081 | ||
1082 | // Compute the additional chi2 (= ((p'-p)^-1)W(p'-p) + ((p'-m)^-1)U(p'-m)) | |
1083 | tmp = newParam; // p' | |
1084 | tmp -= param; // (p'-p) | |
1085 | TMatrixD tmp3(paramWeight,TMatrixD::kMult,tmp); // W(p'-p) | |
1086 | TMatrixD addChi2Track(tmp,TMatrixD::kTransposeMult,tmp3); // ((p'-p)^-1)W(p'-p) | |
1087 | tmp = newParam; // p' | |
1088 | tmp -= clusterParam; // (p'-m) | |
1089 | TMatrixD tmp4(clusterWeight,TMatrixD::kMult,tmp); // U(p'-m) | |
1090 | addChi2Track += TMatrixD(tmp,TMatrixD::kTransposeMult,tmp4); // ((p'-p)^-1)W(p'-p) + ((p'-m)^-1)U(p'-m) | |
1091 | ||
1092 | return addChi2Track(0,0); | |
1093 | ||
1094 | } | |
1095 | ||
1096 | //__________________________________________________________________________ | |
1097 | void AliMUONTrackReconstructorK::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster, Double_t addChi2) | |
1098 | { | |
1099 | /// Add 1 cluster to the track candidate | |
1100 | /// Update chi2 of the track | |
1101 | ||
1102 | // Flag cluster as being (not) removable | |
1103 | if (AliMUONReconstructor::GetRecoParam()->RequestStation(trackParamAtCluster.GetClusterPtr()->GetChamberId()/2)) | |
1104 | trackParamAtCluster.SetRemovable(kFALSE); | |
1105 | else trackParamAtCluster.SetRemovable(kTRUE); | |
1106 | trackParamAtCluster.SetLocalChi2(0.); // --> Local chi2 not used | |
1107 | ||
1108 | // Update the track chi2 into trackParamAtCluster | |
1109 | trackParamAtCluster.SetTrackChi2(track.GetGlobalChi2() + addChi2); | |
1110 | ||
1111 | // Update the chi2 of the new track | |
1112 | track.SetGlobalChi2(trackParamAtCluster.GetTrackChi2()); | |
1113 | ||
1114 | // Update array of TrackParamAtCluster | |
1115 | track.AddTrackParamAtCluster(trackParamAtCluster,*(trackParamAtCluster.GetClusterPtr())); | |
1116 | ||
1117 | } | |
1118 | ||
1119 | //__________________________________________________________________________ | |
1120 | void AliMUONTrackReconstructorK::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster1, AliMUONTrackParam &trackParamAtCluster2, | |
1121 | Double_t addChi2AtCluster1, Double_t addChi2AtCluster2) | |
1122 | { | |
1123 | /// Add 2 clusters to the track candidate (order is important) | |
1124 | /// Update track and local chi2 | |
1125 | ||
1126 | // Update local chi2 at first cluster | |
1127 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
1128 | Double_t deltaX = trackParamAtCluster1.GetNonBendingCoor() - cluster1->GetX(); | |
1129 | Double_t deltaY = trackParamAtCluster1.GetBendingCoor() - cluster1->GetY(); | |
1130 | Double_t localChi2AtCluster1 = deltaX*deltaX / cluster1->GetErrX2() + | |
1131 | deltaY*deltaY / cluster1->GetErrY2(); | |
1132 | trackParamAtCluster1.SetLocalChi2(localChi2AtCluster1); | |
1133 | ||
1134 | // Flag first cluster as being removable | |
1135 | trackParamAtCluster1.SetRemovable(kTRUE); | |
1136 | ||
1137 | // Update local chi2 at second cluster | |
1138 | AliMUONVCluster* cluster2 = trackParamAtCluster2.GetClusterPtr(); | |
1139 | AliMUONTrackParam extrapTrackParamAtCluster2(trackParamAtCluster1); | |
1140 | AliMUONTrackExtrap::ExtrapToZ(&extrapTrackParamAtCluster2, trackParamAtCluster2.GetZ()); | |
1141 | deltaX = extrapTrackParamAtCluster2.GetNonBendingCoor() - cluster2->GetX(); | |
1142 | deltaY = extrapTrackParamAtCluster2.GetBendingCoor() - cluster2->GetY(); | |
1143 | Double_t localChi2AtCluster2 = deltaX*deltaX / cluster2->GetErrX2() + | |
1144 | deltaY*deltaY / cluster2->GetErrY2(); | |
1145 | trackParamAtCluster2.SetLocalChi2(localChi2AtCluster2); | |
1146 | ||
1147 | // Flag second cluster as being removable | |
1148 | trackParamAtCluster2.SetRemovable(kTRUE); | |
1149 | ||
1150 | // Update the track chi2 into trackParamAtCluster2 | |
1151 | trackParamAtCluster2.SetTrackChi2(track.GetGlobalChi2() + addChi2AtCluster2); | |
1152 | ||
1153 | // Update the track chi2 into trackParamAtCluster1 | |
1154 | trackParamAtCluster1.SetTrackChi2(trackParamAtCluster2.GetTrackChi2() + addChi2AtCluster1); | |
1155 | ||
1156 | // Update the chi2 of the new track | |
1157 | track.SetGlobalChi2(trackParamAtCluster1.GetTrackChi2()); | |
1158 | ||
1159 | // Update array of trackParamAtCluster | |
1160 | track.AddTrackParamAtCluster(trackParamAtCluster1,*cluster1); | |
1161 | track.AddTrackParamAtCluster(trackParamAtCluster2,*cluster2); | |
1162 | ||
1163 | } | |
1164 | ||
1165 | //__________________________________________________________________________ | |
1166 | Bool_t AliMUONTrackReconstructorK::RecoverTrack(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) | |
1167 | { | |
1168 | /// Try to recover the track candidate in the next station | |
1169 | /// by removing the worst of the two clusters attached in the current station | |
1170 | /// Return kTRUE if recovering succeeds | |
1171 | AliDebug(1,"Enter RecoverTrack"); | |
1172 | ||
1173 | // Do not try to recover track until we have attached cluster(s) on station(1..) 3 | |
1174 | if (nextStation > 1) return kFALSE; | |
1175 | ||
1176 | Int_t worstClusterNumber = -1; | |
1177 | Double_t localChi2, worstLocalChi2 = -1.; | |
1178 | ||
1179 | // Look for the cluster to remove | |
1180 | for (Int_t clusterNumber = 0; clusterNumber < 2; clusterNumber++) { | |
1181 | AliMUONTrackParam *trackParamAtCluster = (AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(clusterNumber); | |
1182 | ||
1183 | // check if current cluster is in the previous station | |
1184 | if (trackParamAtCluster->GetClusterPtr()->GetChamberId()/2 != nextStation+1) break; | |
1185 | ||
1186 | // check if current cluster is removable | |
1187 | if (!trackParamAtCluster->IsRemovable()) return kFALSE; | |
1188 | ||
1189 | // reset the current cluster as being not removable if it is on a required station | |
1190 | if (AliMUONReconstructor::GetRecoParam()->RequestStation(nextStation+1)) trackParamAtCluster->SetRemovable(kFALSE); | |
1191 | ||
1192 | // Pick up cluster with the worst chi2 | |
1193 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1194 | if (localChi2 > worstLocalChi2) { | |
1195 | worstLocalChi2 = localChi2; | |
1196 | worstClusterNumber = clusterNumber; | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | // check if worst cluster found | |
1201 | if (worstClusterNumber < 0) return kFALSE; | |
1202 | ||
1203 | // Remove the worst cluster | |
1204 | trackCandidate.RemoveTrackParamAtCluster((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(worstClusterNumber)); | |
1205 | ||
1206 | // Re-calculate track parameters at the (new) first cluster | |
1207 | RetracePartialTrack(trackCandidate,(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(1)); | |
1208 | ||
1209 | // skip track with absolute bending momentum out of limits | |
1210 | Double_t bendingMomentum = TMath::Abs(1. / ((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First())->GetInverseBendingMomentum()); | |
1211 | if (bendingMomentum < AliMUONReconstructor::GetRecoParam()->GetMinBendingMomentum() || | |
1212 | bendingMomentum > AliMUONReconstructor::GetRecoParam()->GetMaxBendingMomentum()) return kFALSE; | |
1213 | ||
1214 | // Look for new cluster(s) in next station | |
1215 | return FollowTrackInStation(trackCandidate, clusterStore, nextStation); | |
1216 | ||
1217 | } | |
1218 | ||
1219 | //__________________________________________________________________________ | |
1220 | Bool_t AliMUONTrackReconstructorK::RunSmoother(AliMUONTrack &track) | |
1221 | { | |
1222 | /// Compute new track parameters and their covariances using smoother | |
1223 | AliDebug(1,"Enter UseSmoother"); | |
1224 | ||
1225 | AliMUONTrackParam *previousTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1226 | ||
1227 | // Smoothed parameters and covariances at first cluster = filtered parameters and covariances | |
1228 | previousTrackParam->SetSmoothParameters(previousTrackParam->GetParameters()); | |
1229 | previousTrackParam->SetSmoothCovariances(previousTrackParam->GetCovariances()); | |
1230 | ||
1231 | // Compute local chi2 at first cluster | |
1232 | AliMUONVCluster *cluster = previousTrackParam->GetClusterPtr(); | |
1233 | Double_t dX = cluster->GetX() - previousTrackParam->GetNonBendingCoor(); | |
1234 | Double_t dY = cluster->GetY() - previousTrackParam->GetBendingCoor(); | |
1235 | Double_t localChi2 = dX * dX / cluster->GetErrX2() + dY * dY / cluster->GetErrY2(); | |
1236 | ||
1237 | // Save local chi2 at first cluster | |
1238 | previousTrackParam->SetLocalChi2(localChi2); | |
1239 | ||
1240 | AliMUONTrackParam *currentTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(previousTrackParam); | |
1241 | while (currentTrackParam) { | |
1242 | ||
1243 | // Get variables | |
1244 | const TMatrixD &extrapParameters = previousTrackParam->GetExtrapParameters(); // X(k+1 k) | |
1245 | const TMatrixD &filteredParameters = currentTrackParam->GetParameters(); // X(k k) | |
1246 | const TMatrixD &previousSmoothParameters = previousTrackParam->GetSmoothParameters(); // X(k+1 n) | |
1247 | const TMatrixD &propagator = previousTrackParam->GetPropagator(); // F(k) | |
1248 | const TMatrixD &extrapCovariances = previousTrackParam->GetExtrapCovariances(); // C(k+1 k) | |
1249 | const TMatrixD &filteredCovariances = currentTrackParam->GetCovariances(); // C(k k) | |
1250 | const TMatrixD &previousSmoothCovariances = previousTrackParam->GetSmoothCovariances(); // C(k+1 n) | |
1251 | ||
1252 | // Compute smoother gain: A(k) = C(kk) * F(f)^t * (C(k+1 k))^-1 | |
1253 | TMatrixD extrapWeight(extrapCovariances); | |
1254 | if (extrapWeight.Determinant() != 0) { | |
1255 | extrapWeight.Invert(); // (C(k+1 k))^-1 | |
1256 | } else { | |
1257 | AliWarning(" Determinant = 0"); | |
1258 | return kFALSE; | |
1259 | } | |
1260 | TMatrixD smootherGain(filteredCovariances,TMatrixD::kMultTranspose,propagator); // C(kk) * F(f)^t | |
1261 | smootherGain *= extrapWeight; // C(kk) * F(f)^t * (C(k+1 k))^-1 | |
1262 | ||
1263 | // Compute smoothed parameters: X(k n) = X(k k) + A(k) * (X(k+1 n) - X(k+1 k)) | |
1264 | TMatrixD tmpParam(previousSmoothParameters,TMatrixD::kMinus,extrapParameters); // X(k+1 n) - X(k+1 k) | |
1265 | TMatrixD smoothParameters(smootherGain,TMatrixD::kMult,tmpParam); // A(k) * (X(k+1 n) - X(k+1 k)) | |
1266 | smoothParameters += filteredParameters; // X(k k) + A(k) * (X(k+1 n) - X(k+1 k)) | |
1267 | ||
1268 | // Save smoothed parameters | |
1269 | currentTrackParam->SetSmoothParameters(smoothParameters); | |
1270 | ||
1271 | // Compute smoothed covariances: C(k n) = C(k k) + A(k) * (C(k+1 n) - C(k+1 k)) * (A(k))^t | |
1272 | TMatrixD tmpCov(previousSmoothCovariances,TMatrixD::kMinus,extrapCovariances); // C(k+1 n) - C(k+1 k) | |
1273 | TMatrixD tmpCov2(tmpCov,TMatrixD::kMultTranspose,smootherGain); // (C(k+1 n) - C(k+1 k)) * (A(k))^t | |
1274 | TMatrixD smoothCovariances(smootherGain,TMatrixD::kMult,tmpCov2); // A(k) * (C(k+1 n) - C(k+1 k)) * (A(k))^t | |
1275 | smoothCovariances += filteredCovariances; // C(k k) + A(k) * (C(k+1 n) - C(k+1 k)) * (A(k))^t | |
1276 | ||
1277 | // Save smoothed covariances | |
1278 | currentTrackParam->SetSmoothCovariances(smoothCovariances); | |
1279 | ||
1280 | // Compute smoothed residual: r(k n) = cluster - X(k n) | |
1281 | cluster = currentTrackParam->GetClusterPtr(); | |
1282 | TMatrixD smoothResidual(2,1); | |
1283 | smoothResidual.Zero(); | |
1284 | smoothResidual(0,0) = cluster->GetX() - smoothParameters(0,0); | |
1285 | smoothResidual(1,0) = cluster->GetY() - smoothParameters(2,0); | |
1286 | ||
1287 | // Compute weight of smoothed residual: W(k n) = (clusterCov - C(k n))^-1 | |
1288 | TMatrixD smoothResidualWeight(2,2); | |
1289 | smoothResidualWeight(0,0) = cluster->GetErrX2() - smoothCovariances(0,0); | |
1290 | smoothResidualWeight(0,1) = - smoothCovariances(0,2); | |
1291 | smoothResidualWeight(1,0) = - smoothCovariances(2,0); | |
1292 | smoothResidualWeight(1,1) = cluster->GetErrY2() - smoothCovariances(2,2); | |
1293 | if (smoothResidualWeight.Determinant() != 0) { | |
1294 | smoothResidualWeight.Invert(); | |
1295 | } else { | |
1296 | AliWarning(" Determinant = 0"); | |
1297 | return kFALSE; | |
1298 | } | |
1299 | ||
1300 | // Compute local chi2 = (r(k n))^t * W(k n) * r(k n) | |
1301 | TMatrixD tmpChi2(smoothResidual,TMatrixD::kTransposeMult,smoothResidualWeight); // (r(k n))^t * W(k n) | |
1302 | TMatrixD localChi2(tmpChi2,TMatrixD::kMult,smoothResidual); // (r(k n))^t * W(k n) * r(k n) | |
1303 | ||
1304 | // Save local chi2 | |
1305 | currentTrackParam->SetLocalChi2(localChi2(0,0)); | |
1306 | ||
1307 | previousTrackParam = currentTrackParam; | |
1308 | currentTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(previousTrackParam); | |
1309 | } | |
1310 | ||
1311 | return kTRUE; | |
1312 | ||
1313 | } | |
1314 | ||
1315 | //__________________________________________________________________________ | |
1316 | void AliMUONTrackReconstructorK::ComplementTracks(const AliMUONVClusterStore& clusterStore) | |
1317 | { | |
1318 | /// Complete tracks by adding missing clusters (if there is an overlap between | |
1319 | /// two detection elements, the track may have two clusters in the same chamber) | |
1320 | /// Recompute track parameters and covariances at each clusters | |
1321 | AliDebug(1,"Enter ComplementTracks"); | |
1322 | ||
1323 | Int_t chamberId, detElemId; | |
1324 | Double_t chi2OfCluster, addChi2TrackAtCluster, bestAddChi2TrackAtCluster; | |
1325 | Double_t maxChi2OfCluster = 2. * AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
1326 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
1327 | Bool_t foundOneCluster, trackModified; | |
1328 | AliMUONVCluster *cluster; | |
1329 | AliMUONTrackParam *trackParam, *previousTrackParam, *nextTrackParam, trackParamAtCluster, bestTrackParamAtCluster; | |
1330 | ||
1331 | AliMUONTrack *track = (AliMUONTrack*) fRecTracksPtr->First(); | |
1332 | while (track) { | |
1333 | trackModified = kFALSE; | |
1334 | ||
1335 | trackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->First(); | |
1336 | previousTrackParam = trackParam; | |
1337 | while (trackParam) { | |
1338 | foundOneCluster = kFALSE; | |
1339 | bestAddChi2TrackAtCluster = 1.e10; | |
1340 | chamberId = trackParam->GetClusterPtr()->GetChamberId(); | |
1341 | detElemId = trackParam->GetClusterPtr()->GetDetElemId(); | |
1342 | ||
1343 | // prepare nextTrackParam before adding new cluster because of the sorting | |
1344 | nextTrackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->After(trackParam); | |
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(*trackParam, cluster)) continue; | |
1357 | ||
1358 | // try to add the current cluster accurately | |
1359 | // never use track parameters at last cluster because the covariance matrix is meaningless | |
1360 | if (nextTrackParam) chi2OfCluster = TryOneCluster(*trackParam, cluster, trackParamAtCluster); | |
1361 | else chi2OfCluster = TryOneCluster(*previousTrackParam, cluster, trackParamAtCluster); | |
1362 | ||
1363 | // if good chi2 then consider to add this cluster to the track | |
1364 | if (chi2OfCluster < maxChi2OfCluster) { | |
1365 | ||
1366 | // Compute local track parameters including current cluster using kalman filter | |
1367 | addChi2TrackAtCluster = RunKalmanFilter(trackParamAtCluster); | |
1368 | ||
1369 | // keep track of the best cluster | |
1370 | if (addChi2TrackAtCluster < bestAddChi2TrackAtCluster) { | |
1371 | bestAddChi2TrackAtCluster = addChi2TrackAtCluster; | |
1372 | bestTrackParamAtCluster = trackParamAtCluster; | |
1373 | foundOneCluster = kTRUE; | |
1374 | } | |
1375 | ||
1376 | } | |
1377 | ||
1378 | } | |
1379 | ||
1380 | // add new cluster if any | |
1381 | if (foundOneCluster) { | |
1382 | ||
1383 | // Printout for debuging | |
1384 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1385 | cout << "ComplementTracks: found one cluster in chamber(1..): " << chamberId+1 << endl; | |
1386 | bestTrackParamAtCluster.GetClusterPtr()->Print(); | |
1387 | cout<<endl<<"Track parameters and covariances at cluster:"<<endl; | |
1388 | bestTrackParamAtCluster.GetParameters().Print(); | |
1389 | bestTrackParamAtCluster.GetCovariances().Print(); | |
1390 | } | |
1391 | ||
1392 | trackParam->SetRemovable(kTRUE); | |
1393 | bestTrackParamAtCluster.SetRemovable(kTRUE); | |
1394 | track->AddTrackParamAtCluster(bestTrackParamAtCluster,*(bestTrackParamAtCluster.GetClusterPtr())); | |
1395 | trackModified = kTRUE; | |
1396 | } | |
1397 | ||
1398 | previousTrackParam = trackParam; | |
1399 | trackParam = nextTrackParam; | |
1400 | } | |
1401 | ||
1402 | // re-compute track parameters using kalman filter if needed | |
1403 | if (trackModified) RetraceTrack(*track,kTRUE); | |
1404 | ||
1405 | track = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1406 | } | |
1407 | ||
1408 | } | |
1409 | ||
1410 | //__________________________________________________________________________ | |
1411 | void AliMUONTrackReconstructorK::ImproveTrack(AliMUONTrack &track) | |
1412 | { | |
1413 | /// Improve the given track by removing removable clusters with local chi2 highter than the defined cut | |
1414 | /// Removable clusters are identified by the method AliMUONTrack::TagRemovableClusters() | |
1415 | /// Recompute track parameters and covariances at the remaining clusters | |
1416 | AliDebug(1,"Enter ImproveTrack"); | |
1417 | ||
1418 | Double_t localChi2, worstLocalChi2; | |
1419 | AliMUONTrackParam *trackParamAtCluster, *worstTrackParamAtCluster, *nextTrackParam; | |
1420 | Bool_t smoothed; | |
1421 | Double_t sigmaCut2 = AliMUONReconstructor::GetRecoParam()->GetSigmaCutForImprovement() * | |
1422 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForImprovement(); | |
1423 | ||
1424 | while (!track.IsImproved()) { | |
1425 | ||
1426 | // identify removable clusters | |
1427 | track.TagRemovableClusters(); | |
1428 | ||
1429 | // Run smoother if required | |
1430 | smoothed = kFALSE; | |
1431 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) smoothed = RunSmoother(track); | |
1432 | ||
1433 | // Use standard procedure to compute local chi2 if smoother not required or not working | |
1434 | if (!smoothed) { | |
1435 | ||
1436 | // Update track parameters and covariances | |
1437 | track.UpdateCovTrackParamAtCluster(); | |
1438 | ||
1439 | // Compute local chi2 of each clusters | |
1440 | track.ComputeLocalChi2(kTRUE); | |
1441 | } | |
1442 | ||
1443 | // Look for the cluster to remove | |
1444 | worstTrackParamAtCluster = 0x0; | |
1445 | worstLocalChi2 = 0.; | |
1446 | trackParamAtCluster = (AliMUONTrackParam*)track.GetTrackParamAtCluster()->First(); | |
1447 | while (trackParamAtCluster) { | |
1448 | ||
1449 | // save parameters into smooth parameters in case of smoother did not work properly | |
1450 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother() && !smoothed) { | |
1451 | trackParamAtCluster->SetSmoothParameters(trackParamAtCluster->GetParameters()); | |
1452 | trackParamAtCluster->SetSmoothCovariances(trackParamAtCluster->GetCovariances()); | |
1453 | } | |
1454 | ||
1455 | // Pick up cluster with the worst chi2 | |
1456 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1457 | if (localChi2 > worstLocalChi2) { | |
1458 | worstLocalChi2 = localChi2; | |
1459 | worstTrackParamAtCluster = trackParamAtCluster; | |
1460 | } | |
1461 | ||
1462 | trackParamAtCluster = (AliMUONTrackParam*)track.GetTrackParamAtCluster()->After(trackParamAtCluster); | |
1463 | } | |
1464 | ||
1465 | // Check if worst cluster found | |
1466 | if (!worstTrackParamAtCluster) { | |
1467 | AliWarning("Bad local chi2 values?"); | |
1468 | break; | |
1469 | } | |
1470 | ||
1471 | // Check whether the worst chi2 is under requirement or not | |
1472 | if (worstLocalChi2 < 2. * sigmaCut2) { // 2 because 2 quantities in chi2 | |
1473 | track.SetImproved(kTRUE); | |
1474 | break; | |
1475 | } | |
1476 | ||
1477 | // if the worst cluster is not removable then stop improvement | |
1478 | if (!worstTrackParamAtCluster->IsRemovable()) break; | |
1479 | ||
1480 | // get track parameters at cluster next to the one to be removed | |
1481 | nextTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(worstTrackParamAtCluster); | |
1482 | ||
1483 | // Remove the worst cluster | |
1484 | track.RemoveTrackParamAtCluster(worstTrackParamAtCluster); | |
1485 | ||
1486 | // Re-calculate track parameters | |
1487 | // - from the cluster immediately downstream the one suppressed | |
1488 | // - or from the begining - if parameters have been re-computed using the standard method (kalman parameters have been lost) | |
1489 | // - or if the removed cluster was the last one | |
1490 | if (smoothed && nextTrackParam) RetracePartialTrack(track,nextTrackParam); | |
1491 | else RetraceTrack(track,kTRUE); | |
1492 | ||
1493 | // Printout for debuging | |
1494 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructorK") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1495 | cout << "ImproveTracks: track " << fRecTracksPtr->IndexOf(&track)+1 << " improved " << endl; | |
1496 | } | |
1497 | ||
1498 | } | |
1499 | ||
1500 | } | |
1501 | ||
1502 | //__________________________________________________________________________ | |
1503 | void AliMUONTrackReconstructorK::FinalizeTrack(AliMUONTrack &track) | |
1504 | { | |
1505 | /// Update track parameters and covariances at each attached cluster | |
1506 | /// using smoother if required, if not already done | |
1507 | ||
1508 | AliMUONTrackParam *trackParamAtCluster; | |
1509 | Bool_t smoothed = kFALSE; | |
1510 | ||
1511 | // update track parameters (using smoother if required) if not already done | |
1512 | if (!track.IsImproved()) { | |
1513 | smoothed = kFALSE; | |
1514 | if (AliMUONReconstructor::GetRecoParam()->UseSmoother()) smoothed = RunSmoother(track); | |
1515 | if (!smoothed) track.UpdateCovTrackParamAtCluster(); | |
1516 | } else smoothed = AliMUONReconstructor::GetRecoParam()->UseSmoother(); | |
1517 | ||
1518 | // copy smoothed parameters and covariances if any | |
1519 | if (smoothed) { | |
1520 | ||
1521 | trackParamAtCluster = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->First()); | |
1522 | while (trackParamAtCluster) { | |
1523 | ||
1524 | trackParamAtCluster->SetParameters(trackParamAtCluster->GetSmoothParameters()); | |
1525 | trackParamAtCluster->SetCovariances(trackParamAtCluster->GetSmoothCovariances()); | |
1526 | ||
1527 | trackParamAtCluster = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->After(trackParamAtCluster)); | |
1528 | } | |
1529 | ||
1530 | } | |
1531 | ||
1532 | } | |
1533 | ||
1534 | //__________________________________________________________________________ | |
1535 | Bool_t AliMUONTrackReconstructorK::RefitTrack(AliMUONTrack &track) | |
1536 | { | |
1537 | /// re-fit the given track | |
1538 | ||
1539 | // check validity of the track | |
1540 | if (!track.IsValid()) { | |
1541 | AliWarning("the track does not contain enough clusters --> unable to refit"); | |
1542 | return kFALSE; | |
1543 | } | |
1544 | ||
1545 | // re-compute track parameters and covariances using Kalman filter | |
1546 | RetraceTrack(track,kTRUE); | |
1547 | ||
1548 | // Improve the reconstructed tracks if required | |
1549 | if (AliMUONReconstructor::GetRecoParam()->ImproveTracks()) ImproveTrack(track); | |
1550 | ||
1551 | // Fill AliMUONTrack data members | |
1552 | FinalizeTrack(track); | |
1553 | ||
1554 | return kTRUE; | |
1555 | ||
1556 | } | |
1557 |