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a9e2aefa | 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 | ||
cc87ebcd | 16 | /* $Id$ */ |
17 | ||
3d1463c8 | 18 | //----------------------------------------------------------------------------- |
7945aae7 | 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 | |
3d1463c8 | 27 | //----------------------------------------------------------------------------- |
a9e2aefa | 28 | |
29f1b13a | 29 | #include "AliMUONTrackReconstructor.h" |
7ec3b9cf | 30 | |
29fc2c86 | 31 | #include "AliMUONConstants.h" |
96ebe67e | 32 | #include "AliMUONVCluster.h" |
1fef78c8 | 33 | #include "AliMUONVClusterServer.h" |
96ebe67e | 34 | #include "AliMUONVClusterStore.h" |
a9e2aefa | 35 | #include "AliMUONTrack.h" |
37827b29 | 36 | #include "AliMUONTrackParam.h" |
37 | #include "AliMUONTrackExtrap.h" | |
5a240757 | 38 | #include "AliMUONRecoParam.h" |
b709ac13 | 39 | |
1fef78c8 | 40 | #include "AliMpArea.h" |
41 | ||
8c343c7c | 42 | #include "AliLog.h" |
af743f54 | 43 | |
208f139e | 44 | #include <TMinuit.h> |
af743f54 | 45 | #include <Riostream.h> |
ea94c18b | 46 | #include <TMath.h> |
af743f54 | 47 | #include <TMatrixD.h> |
a9e2aefa | 48 | |
de2cd600 | 49 | // Functions to be minimized with Minuit |
ea94c18b | 50 | void TrackChi2(Int_t &nParam, Double_t *gradient, Double_t &chi2, Double_t *param, Int_t flag); |
de2cd600 | 51 | |
7945aae7 | 52 | /// \cond CLASSIMP |
29f1b13a | 53 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context |
7945aae7 | 54 | /// \endcond |
a9e2aefa | 55 | |
019df241 | 56 | //__________________________________________________________________________ |
a0dc65b4 | 57 | AliMUONTrackReconstructor::AliMUONTrackReconstructor(const AliMUONRecoParam* recoParam, AliMUONVClusterServer* clusterServer) |
58 | : AliMUONVTrackReconstructor(recoParam,clusterServer) | |
a9e2aefa | 59 | { |
96ebe67e | 60 | /// Constructor |
a9e2aefa | 61 | } |
9cbdf048 | 62 | |
019df241 | 63 | //__________________________________________________________________________ |
ea94c18b | 64 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor() |
a9e2aefa | 65 | { |
ea94c18b | 66 | /// Destructor |
67 | } | |
276c44b7 | 68 | |
de2cd600 | 69 | //__________________________________________________________________________ |
1fef78c8 | 70 | void AliMUONTrackReconstructor::MakeTrackCandidates(AliMUONVClusterStore& clusterStore) |
de2cd600 | 71 | { |
019df241 | 72 | /// To make track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): |
208f139e | 73 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. |
96ebe67e | 74 | /// Good candidates are made of at least three clusters. |
208f139e | 75 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. |
b709ac13 | 76 | |
208f139e | 77 | TClonesArray *segments; |
208f139e | 78 | AliMUONTrack *track; |
208f139e | 79 | Int_t iCandidate = 0; |
96ebe67e | 80 | Bool_t clusterFound; |
208f139e | 81 | |
de2cd600 | 82 | AliDebug(1,"Enter MakeTrackCandidates"); |
de2cd600 | 83 | |
3a7acd03 | 84 | // Unless we're doing combined tracking, we'll clusterize all stations at once |
85 | Int_t firstChamber(0); | |
86 | Int_t lastChamber(9); | |
87 | ||
a0dc65b4 | 88 | if (GetRecoParam()->CombineClusterTrackReco()) { |
3a7acd03 | 89 | // ... Here's the exception : ask the clustering to reconstruct |
90 | // clusters *only* in station 4 and 5 for combined tracking | |
91 | firstChamber = 6; | |
92 | } | |
93 | ||
94 | for (Int_t i = firstChamber; i <= lastChamber; ++i ) | |
95 | { | |
35be7ed7 | 96 | if (fClusterServer && GetRecoParam()->UseChamber(i)) fClusterServer->Clusterize(i, clusterStore, AliMpArea(), GetRecoParam()); |
1fef78c8 | 97 | } |
98 | ||
208f139e | 99 | // Loop over stations(1..) 5 and 4 and make track candidates |
ea94c18b | 100 | for (Int_t istat=4; istat>=3; istat--) { |
101 | ||
208f139e | 102 | // Make segments in the station |
9bf6860b | 103 | segments = MakeSegmentsBetweenChambers(clusterStore, 2*istat, 2*istat+1); |
ea94c18b | 104 | |
208f139e | 105 | // Loop over segments |
7ec3b9cf | 106 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) |
107 | { | |
208f139e | 108 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); |
ea94c18b | 109 | |
208f139e | 110 | // Transform segments to tracks and put them at the end of fRecTracksPtr |
a0dc65b4 | 111 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg]),GetRecoParam()->GetBendingVertexDispersion()); |
a9e2aefa | 112 | fNRecTracks++; |
ea94c18b | 113 | |
96ebe67e | 114 | // Look for compatible cluster(s) in the other station |
a0dc65b4 | 115 | if (GetRecoParam()->MakeTrackCandidatesFast()) |
96ebe67e | 116 | clusterFound = FollowLinearTrackInStation(*track, clusterStore, 7-istat); |
117 | else clusterFound = FollowTrackInStation(*track, clusterStore, 7-istat); | |
019df241 | 118 | |
96ebe67e | 119 | // Remove track if no cluster found |
a0dc65b4 | 120 | if (!clusterFound && GetRecoParam()->RequestStation(7-istat)) { |
ea94c18b | 121 | fRecTracksPtr->Remove(track); |
122 | fNRecTracks--; | |
123 | } | |
124 | ||
a9e2aefa | 125 | } |
ea94c18b | 126 | |
208f139e | 127 | // delete the array of segments |
128 | delete segments; | |
129 | } | |
ea94c18b | 130 | |
208f139e | 131 | fRecTracksPtr->Compress(); // this is essential before checking tracks |
132 | ||
133 | // Keep all different tracks or only the best ones as required | |
a0dc65b4 | 134 | if (GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); |
208f139e | 135 | else RemoveDoubleTracks(); |
136 | ||
137 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
138 | ||
9bf6860b | 139 | } |
140 | ||
141 | //__________________________________________________________________________ | |
142 | void AliMUONTrackReconstructor::MakeMoreTrackCandidates(AliMUONVClusterStore& clusterStore) | |
143 | { | |
144 | /// To make extra track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
145 | /// clustering is supposed to be already done | |
146 | /// Start with segments made of 1 cluster in each of the stations 4 and 5 then follow track in remaining chambers. | |
147 | /// Good candidates are made of at least three clusters if both station are requested (two otherwise). | |
148 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
149 | ||
150 | TClonesArray *segments; | |
151 | AliMUONTrack *track; | |
152 | Int_t iCandidate = 0, iCurrentTrack, nCurrentTracks; | |
153 | Bool_t clusterFound; | |
154 | ||
155 | AliDebug(1,"Enter MakeMoreTrackCandidates"); | |
156 | ||
157 | // Double loop over chambers in stations(1..) 4 and 5 to make track candidates | |
158 | for (Int_t ich1 = 6; ich1 <= 7; ich1++) { | |
159 | for (Int_t ich2 = 8; ich2 <= 9; ich2++) { | |
160 | ||
161 | // Make segments in the station | |
162 | segments = MakeSegmentsBetweenChambers(clusterStore, ich1, ich2); | |
163 | ||
164 | // Loop over segments | |
165 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) | |
166 | { | |
167 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
168 | ||
169 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
170 | iCurrentTrack = fRecTracksPtr->GetLast()+1; | |
a0dc65b4 | 171 | track = new ((*fRecTracksPtr)[iCurrentTrack]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg]),GetRecoParam()->GetBendingVertexDispersion()); |
9bf6860b | 172 | fNRecTracks++; |
173 | ||
174 | // Look for compatible cluster(s) in the second chamber of station 5 | |
a0dc65b4 | 175 | if (GetRecoParam()->MakeTrackCandidatesFast()) |
9bf6860b | 176 | clusterFound = FollowLinearTrackInChamber(*track, clusterStore, 17-ich2); |
177 | else clusterFound = FollowTrackInChamber(*track, clusterStore, 17-ich2); | |
178 | ||
179 | // skip the original track in case it has been removed | |
a0dc65b4 | 180 | if (GetRecoParam()->TrackAllTracks() && clusterFound) iCurrentTrack++; |
9bf6860b | 181 | |
182 | // loop over every new tracks | |
183 | nCurrentTracks = fRecTracksPtr->GetLast()+1; | |
184 | while (iCurrentTrack < nCurrentTracks) { | |
185 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iCurrentTrack); | |
186 | ||
187 | // Look for compatible cluster(s) in the second chamber of station 4 | |
a0dc65b4 | 188 | if (GetRecoParam()->MakeTrackCandidatesFast()) |
9bf6860b | 189 | FollowLinearTrackInChamber(*track, clusterStore, 13-ich1); |
190 | else FollowTrackInChamber(*track, clusterStore, 13-ich1); | |
191 | ||
192 | iCurrentTrack++; | |
193 | } | |
194 | ||
195 | } | |
196 | ||
197 | // delete the array of segments | |
198 | delete segments; | |
199 | } | |
200 | } | |
201 | ||
202 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
203 | ||
204 | // Keep all different tracks or only the best ones as required | |
a0dc65b4 | 205 | if (GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); |
9bf6860b | 206 | else RemoveDoubleTracks(); |
207 | ||
208 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
209 | ||
a9e2aefa | 210 | } |
211 | ||
212 | //__________________________________________________________________________ | |
1fef78c8 | 213 | void AliMUONTrackReconstructor::FollowTracks(AliMUONVClusterStore& clusterStore) |
a9e2aefa | 214 | { |
2457f726 | 215 | /// Follow tracks in stations(1..) 3, 2 and 1 |
208f139e | 216 | AliDebug(1,"Enter FollowTracks"); |
217 | ||
04b5ea16 | 218 | AliMUONTrack *track, *nextTrack; |
b709ac13 | 219 | AliMUONTrackParam *trackParam, *nextTrackParam; |
af743f54 | 220 | Int_t currentNRecTracks; |
208f139e | 221 | |
a0dc65b4 | 222 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * |
223 | GetRecoParam()->GetSigmaCutForTracking(); | |
3304fa09 | 224 | |
208f139e | 225 | for (Int_t station = 2; station >= 0; station--) { |
ea94c18b | 226 | |
208f139e | 227 | // Save the actual number of reconstructed track in case of |
228 | // tracks are added or suppressed during the tracking procedure | |
229 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
af743f54 | 230 | currentNRecTracks = fNRecTracks; |
ea94c18b | 231 | |
af743f54 | 232 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { |
208f139e | 233 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); |
ea94c18b | 234 | |
208f139e | 235 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); |
ea94c18b | 236 | |
208f139e | 237 | // Fit the track: |
238 | // Do not take into account the multiple scattering to speed up the fit | |
239 | // Calculate the track parameter covariance matrix | |
9bf6860b | 240 | // If there is no cluster out of station 4 or 5 then use the vertex to better constrain the fit |
241 | if (((AliMUONTrackParam*) track->GetTrackParamAtCluster()->First())->GetClusterPtr()->GetChamberId() > 5) | |
242 | Fit(*track, kFALSE, kTRUE, kTRUE); | |
96ebe67e | 243 | else Fit(*track, kFALSE, kFALSE, kTRUE); |
ea94c18b | 244 | |
9bf6860b | 245 | // remove track with absolute bending momentum out of limits |
246 | // or if the normalized chi2 is too high | |
247 | Double_t bendingMomentum = TMath::Abs(1. / ((AliMUONTrackParam*)track->GetTrackParamAtCluster()->First())->GetInverseBendingMomentum()); | |
a0dc65b4 | 248 | if (bendingMomentum < GetRecoParam()->GetMinBendingMomentum() || |
249 | bendingMomentum > GetRecoParam()->GetMaxBendingMomentum() || | |
9bf6860b | 250 | track->GetNormalizedChi2() > sigmaCut2) { |
251 | fRecTracksPtr->Remove(track); | |
208f139e | 252 | fNRecTracks--; |
253 | continue; | |
254 | } | |
ea94c18b | 255 | |
b709ac13 | 256 | // save parameters from fit into smoothed parameters to complete track afterward |
a0dc65b4 | 257 | if (GetRecoParam()->ComplementTracks()) { |
b709ac13 | 258 | |
259 | if (station==2) { // save track parameters on stations 4 and 5 | |
260 | ||
261 | // extrapolate track parameters and covariances at each cluster | |
96ebe67e | 262 | track->UpdateCovTrackParamAtCluster(); |
b709ac13 | 263 | |
264 | // save them | |
96ebe67e | 265 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
b709ac13 | 266 | while (trackParam) { |
267 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
268 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
96ebe67e | 269 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 270 | } |
271 | ||
272 | } else { // or save track parameters on last station only | |
273 | ||
96ebe67e | 274 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
9bf6860b | 275 | if (trackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { |
b709ac13 | 276 | |
9bf6860b | 277 | // save parameters from fit |
278 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
279 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
b709ac13 | 280 | |
9bf6860b | 281 | // save parameters extrapolated to the second chamber of the same station if it has been hit |
282 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
283 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { | |
284 | ||
285 | // reset parameters and covariances | |
286 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
287 | nextTrackParam->SetZ(trackParam->GetZ()); | |
288 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
289 | ||
290 | // extrapolate them to the z of the corresponding cluster | |
291 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); | |
292 | ||
293 | // save them | |
294 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
295 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
296 | ||
297 | } | |
b709ac13 | 298 | |
299 | } | |
300 | ||
301 | } | |
302 | ||
303 | } | |
304 | ||
96ebe67e | 305 | // Look for compatible cluster(s) in station(0..) "station" |
9bf6860b | 306 | if (!FollowTrackInStation(*track, clusterStore, station)) { |
307 | ||
308 | // Try to recover track if required | |
a0dc65b4 | 309 | if (GetRecoParam()->RecoverTracks()) { |
9bf6860b | 310 | |
311 | // work on a copy of the track if this station is not required | |
312 | // to keep the case where no cluster is reconstructed as a possible candidate | |
a0dc65b4 | 313 | if (!GetRecoParam()->RequestStation(station)) { |
9bf6860b | 314 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*track); |
315 | fNRecTracks++; | |
316 | } | |
317 | ||
318 | // try to recover | |
319 | if (!RecoverTrack(*track, clusterStore, station)) { | |
320 | // remove track if no cluster found | |
321 | fRecTracksPtr->Remove(track); | |
322 | fNRecTracks--; | |
323 | } | |
324 | ||
a0dc65b4 | 325 | } else if (GetRecoParam()->RequestStation(station)) { |
9bf6860b | 326 | // remove track if no cluster found |
327 | fRecTracksPtr->Remove(track); | |
328 | fNRecTracks--; | |
329 | } | |
330 | ||
ea94c18b | 331 | } |
332 | ||
208f139e | 333 | } |
ea94c18b | 334 | |
208f139e | 335 | // Compress fRecTracksPtr for the next step |
336 | fRecTracksPtr->Compress(); | |
ea94c18b | 337 | |
208f139e | 338 | // Keep only the best tracks if required |
a0dc65b4 | 339 | if (!GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); |
ea94c18b | 340 | |
208f139e | 341 | } |
342 | ||
96ebe67e | 343 | // Last fit of track candidates with all stations |
208f139e | 344 | // Take into account the multiple scattering and remove bad tracks |
345 | Int_t trackIndex = -1; | |
04b5ea16 | 346 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
04b5ea16 | 347 | while (track) { |
ea94c18b | 348 | |
04b5ea16 | 349 | trackIndex++; |
350 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
ea94c18b | 351 | |
96ebe67e | 352 | Fit(*track, kTRUE, kFALSE, kTRUE); |
ea94c18b | 353 | |
208f139e | 354 | // Printout for debuging |
355 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
356 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
a9e2aefa | 357 | track->RecursiveDump(); |
208f139e | 358 | } |
ea94c18b | 359 | |
208f139e | 360 | // Remove the track if the normalized chi2 is too high |
3304fa09 | 361 | if (track->GetNormalizedChi2() > sigmaCut2) { |
208f139e | 362 | fRecTracksPtr->Remove(track); |
363 | fNRecTracks--; | |
6d9a2d45 | 364 | track = nextTrack; |
365 | continue; | |
a9e2aefa | 366 | } |
ea94c18b | 367 | |
b709ac13 | 368 | // save parameters from fit into smoothed parameters to complete track afterward |
a0dc65b4 | 369 | if (GetRecoParam()->ComplementTracks()) { |
b709ac13 | 370 | |
96ebe67e | 371 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
9bf6860b | 372 | if (trackParam->GetClusterPtr()->GetChamberId() < 2) { |
b709ac13 | 373 | |
9bf6860b | 374 | // save parameters from fit |
375 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
376 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
b709ac13 | 377 | |
9bf6860b | 378 | // save parameters extrapolated to the second chamber of the same station if it has been hit |
379 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
380 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2) { | |
381 | ||
382 | // reset parameters and covariances | |
383 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
384 | nextTrackParam->SetZ(trackParam->GetZ()); | |
385 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
386 | ||
387 | // extrapolate them to the z of the corresponding cluster | |
388 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); | |
389 | ||
390 | // save them | |
391 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
392 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
393 | ||
394 | } | |
b709ac13 | 395 | |
396 | } | |
397 | ||
398 | } | |
399 | ||
208f139e | 400 | track = nextTrack; |
ea94c18b | 401 | |
208f139e | 402 | } |
ea94c18b | 403 | |
208f139e | 404 | fRecTracksPtr->Compress(); |
405 | ||
9bf6860b | 406 | } |
407 | ||
408 | //__________________________________________________________________________ | |
409 | Bool_t AliMUONTrackReconstructor::FollowTrackInChamber(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextChamber) | |
410 | { | |
411 | /// Follow trackCandidate in chamber(0..) nextChamber and search for compatible cluster(s) | |
412 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
413 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
414 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
415 | /// Remove the obsolete "trackCandidate" at the end. | |
416 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
417 | AliDebug(1,Form("Enter FollowTrackInChamber(1..) %d", nextChamber+1)); | |
418 | ||
419 | Double_t chi2WithOneCluster = 1.e10; | |
a0dc65b4 | 420 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * |
421 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
9bf6860b | 422 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; |
423 | Bool_t foundOneCluster = kFALSE; | |
424 | AliMUONTrack *newTrack = 0x0; | |
425 | AliMUONVCluster *cluster; | |
426 | AliMUONTrackParam extrapTrackParam; | |
427 | AliMUONTrackParam extrapTrackParamAtCh; | |
428 | AliMUONTrackParam extrapTrackParamAtCluster; | |
429 | AliMUONTrackParam bestTrackParamAtCluster; | |
430 | ||
431 | // Get track parameters according to the propagation direction | |
432 | if (nextChamber > 7) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
433 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
434 | ||
435 | // Printout for debuging | |
436 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
437 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
438 | extrapTrackParamAtCh.GetParameters().Print(); | |
439 | extrapTrackParamAtCh.GetCovariances().Print(); | |
440 | } | |
441 | ||
442 | // Add MCS effect | |
443 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
444 | ||
445 | // Add MCS in the missing chamber(s) if any | |
446 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
447 | while (currentChamber > nextChamber + 1) { | |
448 | // extrapolation to the missing chamber | |
449 | currentChamber--; | |
450 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber)); | |
451 | // add MCS effect | |
452 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
453 | } | |
454 | ||
455 | //Extrapolate trackCandidate to chamber | |
456 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(nextChamber)); | |
457 | ||
458 | // Printout for debuging | |
459 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
460 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(nextChamber)<<":"<<endl; | |
461 | extrapTrackParamAtCh.GetParameters().Print(); | |
462 | extrapTrackParamAtCh.GetCovariances().Print(); | |
463 | } | |
464 | ||
465 | // Printout for debuging | |
466 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
467 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << nextChamber+1 << endl; | |
468 | } | |
469 | ||
470 | // Ask the clustering to reconstruct new clusters around the track position in the current chamber | |
471 | // except for station 4 and 5 that are already entirely clusterized | |
a0dc65b4 | 472 | if (GetRecoParam()->CombineClusterTrackReco()) { |
9bf6860b | 473 | if (nextChamber < 6) AskForNewClustersInChamber(extrapTrackParamAtCh, clusterStore, nextChamber); |
474 | } | |
475 | ||
476 | // Create iterators to loop over clusters in both chambers | |
477 | TIter next(clusterStore.CreateChamberIterator(nextChamber,nextChamber)); | |
478 | ||
479 | // look for cluster in chamber | |
480 | while ( ( cluster = static_cast<AliMUONVCluster*>(next()) ) ) { | |
481 | ||
482 | // try to add the current cluster fast | |
483 | if (!TryOneClusterFast(extrapTrackParamAtCh, cluster)) continue; | |
484 | ||
485 | // try to add the current cluster accuratly | |
486 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, cluster, extrapTrackParamAtCluster); | |
487 | ||
488 | // if good chi2 then consider to add cluster | |
489 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
490 | foundOneCluster = kTRUE; | |
491 | ||
492 | // Printout for debuging | |
493 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
494 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << nextChamber+1 | |
495 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
496 | cluster->Print(); | |
497 | } | |
498 | ||
a0dc65b4 | 499 | if (GetRecoParam()->TrackAllTracks()) { |
9bf6860b | 500 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
501 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
502 | UpdateTrack(*newTrack,extrapTrackParamAtCluster); | |
503 | fNRecTracks++; | |
504 | ||
505 | // Printout for debuging | |
506 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
507 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << nextChamber+1 << endl; | |
508 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
509 | } | |
510 | ||
511 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { | |
512 | // keep track of the best single cluster except if a couple of clusters has already been found | |
513 | bestChi2WithOneCluster = chi2WithOneCluster; | |
514 | bestTrackParamAtCluster = extrapTrackParamAtCluster; | |
515 | } | |
516 | ||
517 | } | |
518 | ||
519 | } | |
520 | ||
521 | // fill out the best track if required else clean up the fRecTracksPtr array | |
a0dc65b4 | 522 | if (!GetRecoParam()->TrackAllTracks()) { |
9bf6860b | 523 | if (foundOneCluster) { |
524 | UpdateTrack(trackCandidate,bestTrackParamAtCluster); | |
525 | ||
526 | // Printout for debuging | |
527 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
528 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster.GetClusterPtr()->GetChamberId()+1 << endl; | |
529 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
530 | } | |
531 | ||
532 | } else return kFALSE; | |
533 | ||
534 | } else if (foundOneCluster) { | |
535 | ||
536 | // remove obsolete track | |
537 | fRecTracksPtr->Remove(&trackCandidate); | |
538 | fNRecTracks--; | |
539 | ||
540 | } else return kFALSE; | |
541 | ||
542 | return kTRUE; | |
543 | ||
208f139e | 544 | } |
1a38e749 | 545 | |
208f139e | 546 | //__________________________________________________________________________ |
1fef78c8 | 547 | Bool_t AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) |
208f139e | 548 | { |
96ebe67e | 549 | /// Follow trackCandidate in station(0..) nextStation and search for compatible cluster(s) |
208f139e | 550 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: |
551 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
552 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
553 | /// Remove the obsolete "trackCandidate" at the end. | |
96ebe67e | 554 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. |
208f139e | 555 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); |
556 | ||
ea94c18b | 557 | // Order the chamber according to the propagation direction (tracking starts with chamber 2): |
558 | // - nextStation == station(1...) 5 => forward propagation | |
559 | // - nextStation < station(1...) 5 => backward propagation | |
560 | Int_t ch1, ch2; | |
561 | if (nextStation==4) { | |
562 | ch1 = 2*nextStation+1; | |
563 | ch2 = 2*nextStation; | |
564 | } else { | |
565 | ch1 = 2*nextStation; | |
566 | ch2 = 2*nextStation+1; | |
567 | } | |
568 | ||
96ebe67e | 569 | Double_t chi2WithOneCluster = 1.e10; |
570 | Double_t chi2WithTwoClusters = 1.e10; | |
a0dc65b4 | 571 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * |
572 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
573 | Double_t maxChi2WithTwoClusters = 4. * GetRecoParam()->GetSigmaCutForTracking() * | |
574 | GetRecoParam()->GetSigmaCutForTracking(); // 4 because 4 quantities in chi2 | |
96ebe67e | 575 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; |
576 | Double_t bestChi2WithTwoClusters = maxChi2WithTwoClusters; | |
577 | Bool_t foundOneCluster = kFALSE; | |
578 | Bool_t foundTwoClusters = kFALSE; | |
208f139e | 579 | AliMUONTrack *newTrack = 0x0; |
96ebe67e | 580 | AliMUONVCluster *clusterCh1, *clusterCh2; |
019df241 | 581 | AliMUONTrackParam extrapTrackParam; |
7332f213 | 582 | AliMUONTrackParam extrapTrackParamAtCh; |
96ebe67e | 583 | AliMUONTrackParam extrapTrackParamAtCluster1; |
584 | AliMUONTrackParam extrapTrackParamAtCluster2; | |
585 | AliMUONTrackParam bestTrackParamAtCluster1; | |
586 | AliMUONTrackParam bestTrackParamAtCluster2; | |
587 | ||
588 | Int_t nClusters = clusterStore.GetSize(); | |
589 | Bool_t *clusterCh1Used = new Bool_t[nClusters]; | |
590 | for (Int_t i = 0; i < nClusters; i++) clusterCh1Used[i] = kFALSE; | |
591 | Int_t iCluster1; | |
ea94c18b | 592 | |
7332f213 | 593 | // Get track parameters according to the propagation direction |
594 | if (nextStation==4) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
595 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
ea94c18b | 596 | |
9bf6860b | 597 | // Printout for debuging |
598 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
599 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
600 | extrapTrackParamAtCh.GetParameters().Print(); | |
601 | extrapTrackParamAtCh.GetCovariances().Print(); | |
602 | } | |
603 | ||
ea94c18b | 604 | // Add MCS effect |
019df241 | 605 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 606 | |
9bf6860b | 607 | // Add MCS in the missing chamber(s) if any |
608 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
609 | while (ch1 < ch2 && currentChamber > ch2 + 1) { | |
ea94c18b | 610 | // extrapolation to the missing chamber |
9bf6860b | 611 | currentChamber--; |
612 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber)); | |
ea94c18b | 613 | // add MCS effect |
019df241 | 614 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 615 | } |
616 | ||
617 | //Extrapolate trackCandidate to chamber "ch2" | |
019df241 | 618 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2)); |
ea94c18b | 619 | |
208f139e | 620 | // Printout for debuging |
621 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
9bf6860b | 622 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch2)<<":"<<endl; |
623 | extrapTrackParamAtCh.GetParameters().Print(); | |
019df241 | 624 | extrapTrackParamAtCh.GetCovariances().Print(); |
208f139e | 625 | } |
ea94c18b | 626 | |
208f139e | 627 | // Printout for debuging |
628 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 629 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << ch2+1 << endl; |
208f139e | 630 | } |
ea94c18b | 631 | |
1fef78c8 | 632 | // Ask the clustering to reconstruct new clusters around the track position in the current station |
633 | // except for station 4 and 5 that are already entirely clusterized | |
a0dc65b4 | 634 | if (GetRecoParam()->CombineClusterTrackReco()) { |
1fef78c8 | 635 | if (nextStation < 3) AskForNewClustersInStation(extrapTrackParamAtCh, clusterStore, nextStation); |
636 | } | |
637 | ||
96ebe67e | 638 | // Create iterators to loop over clusters in both chambers |
639 | TIter nextInCh1(clusterStore.CreateChamberIterator(ch1,ch1)); | |
640 | TIter nextInCh2(clusterStore.CreateChamberIterator(ch2,ch2)); | |
641 | ||
642 | // look for candidates in chamber 2 | |
643 | while ( ( clusterCh2 = static_cast<AliMUONVCluster*>(nextInCh2()) ) ) { | |
ea94c18b | 644 | |
96ebe67e | 645 | // try to add the current cluster fast |
646 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh2)) continue; | |
019df241 | 647 | |
96ebe67e | 648 | // try to add the current cluster accuratly |
649 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh2, extrapTrackParamAtCluster2); | |
ea94c18b | 650 | |
96ebe67e | 651 | // if good chi2 then try to attach a cluster in the other chamber too |
652 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
653 | Bool_t foundSecondCluster = kFALSE; | |
ea94c18b | 654 | |
208f139e | 655 | // Printout for debuging |
656 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 657 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch2+1 |
658 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
9bf6860b | 659 | clusterCh2->Print(); |
96ebe67e | 660 | cout << " look for second clusters in chamber(1..): " << ch1+1 << " ..." << endl; |
a9e2aefa | 661 | } |
ea94c18b | 662 | |
663 | // add MCS effect for next step | |
96ebe67e | 664 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCluster2,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 665 | |
019df241 | 666 | // copy new track parameters for next step |
96ebe67e | 667 | extrapTrackParam = extrapTrackParamAtCluster2; |
019df241 | 668 | |
669 | //Extrapolate track parameters to chamber "ch1" | |
670 | AliMUONTrackExtrap::ExtrapToZ(&extrapTrackParam, AliMUONConstants::DefaultChamberZ(ch1)); | |
671 | ||
96ebe67e | 672 | // reset cluster iterator of chamber 1 |
673 | nextInCh1.Reset(); | |
674 | iCluster1 = -1; | |
675 | ||
676 | // look for second candidates in chamber 1 | |
677 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
678 | iCluster1++; | |
ea94c18b | 679 | |
96ebe67e | 680 | // try to add the current cluster fast |
681 | if (!TryOneClusterFast(extrapTrackParam, clusterCh1)) continue; | |
019df241 | 682 | |
96ebe67e | 683 | // try to add the current cluster accuratly |
684 | chi2WithTwoClusters = TryTwoClusters(extrapTrackParamAtCluster2, clusterCh1, extrapTrackParamAtCluster1); | |
ea94c18b | 685 | |
96ebe67e | 686 | // if good chi2 then create a new track by adding the 2 clusters to the "trackCandidate" |
687 | if (chi2WithTwoClusters < maxChi2WithTwoClusters) { | |
688 | foundSecondCluster = kTRUE; | |
689 | foundTwoClusters = kTRUE; | |
ea94c18b | 690 | |
691 | // Printout for debuging | |
692 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 693 | cout << "FollowTrackInStation: found second cluster in chamber(1..): " << ch1+1 |
9bf6860b | 694 | << " (Global Chi2 = " << chi2WithTwoClusters << ")" << endl; |
695 | clusterCh1->Print(); | |
ea94c18b | 696 | } |
697 | ||
a0dc65b4 | 698 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 699 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new clusters |
ea94c18b | 700 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 701 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,extrapTrackParamAtCluster2); |
208f139e | 702 | fNRecTracks++; |
ea94c18b | 703 | |
96ebe67e | 704 | // Tag clusterCh1 as used |
705 | clusterCh1Used[iCluster1] = kTRUE; | |
ea94c18b | 706 | |
208f139e | 707 | // Printout for debuging |
708 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 709 | cout << "FollowTrackInStation: added two clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 710 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 711 | } |
ea94c18b | 712 | |
96ebe67e | 713 | } else if (chi2WithTwoClusters < bestChi2WithTwoClusters) { |
714 | // keep track of the best couple of clusters | |
715 | bestChi2WithTwoClusters = chi2WithTwoClusters; | |
716 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
717 | bestTrackParamAtCluster2 = extrapTrackParamAtCluster2; | |
208f139e | 718 | } |
ea94c18b | 719 | |
a9e2aefa | 720 | } |
ea94c18b | 721 | |
d0bfce8d | 722 | } |
ea94c18b | 723 | |
96ebe67e | 724 | // if no clusterCh1 found then consider to add clusterCh2 only |
725 | if (!foundSecondCluster) { | |
726 | foundOneCluster = kTRUE; | |
ea94c18b | 727 | |
a0dc65b4 | 728 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 729 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 730 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 731 | UpdateTrack(*newTrack,extrapTrackParamAtCluster2); |
208f139e | 732 | fNRecTracks++; |
ea94c18b | 733 | |
208f139e | 734 | // Printout for debuging |
735 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 736 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch2+1 << endl; |
208f139e | 737 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
738 | } | |
ea94c18b | 739 | |
96ebe67e | 740 | } else if (!foundTwoClusters && chi2WithOneCluster < bestChi2WithOneCluster) { |
741 | // keep track of the best single cluster except if a couple of clusters has already been found | |
742 | bestChi2WithOneCluster = chi2WithOneCluster; | |
743 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster2; | |
208f139e | 744 | } |
ea94c18b | 745 | |
d0bfce8d | 746 | } |
ea94c18b | 747 | |
208f139e | 748 | } |
ea94c18b | 749 | |
208f139e | 750 | } |
ea94c18b | 751 | |
208f139e | 752 | // look for candidates in chamber 1 not already attached to a track |
96ebe67e | 753 | // if we want to keep all possible tracks or if no good couple of clusters has been found |
a0dc65b4 | 754 | if (GetRecoParam()->TrackAllTracks() || !foundTwoClusters) { |
ea94c18b | 755 | |
ea94c18b | 756 | // add MCS effect for next step |
019df241 | 757 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
758 | ||
759 | //Extrapolate trackCandidate to chamber "ch1" | |
760 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch1)); | |
761 | ||
9bf6860b | 762 | // Printout for debuging |
763 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
764 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch1)<<":"<<endl; | |
765 | extrapTrackParamAtCh.GetParameters().Print(); | |
766 | extrapTrackParamAtCh.GetCovariances().Print(); | |
767 | } | |
768 | ||
769 | // Printout for debuging | |
770 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
771 | cout << "FollowTrackInStation: look for single clusters in chamber(1..): " << ch1+1 << endl; | |
772 | } | |
773 | ||
96ebe67e | 774 | // reset cluster iterator of chamber 1 |
775 | nextInCh1.Reset(); | |
776 | iCluster1 = -1; | |
777 | ||
778 | // look for second candidates in chamber 1 | |
779 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
780 | iCluster1++; | |
ea94c18b | 781 | |
96ebe67e | 782 | if (clusterCh1Used[iCluster1]) continue; // Skip cluster already used |
ea94c18b | 783 | |
96ebe67e | 784 | // try to add the current cluster fast |
785 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh1)) continue; | |
019df241 | 786 | |
96ebe67e | 787 | // try to add the current cluster accuratly |
788 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh1, extrapTrackParamAtCluster1); | |
9bf6860b | 789 | |
96ebe67e | 790 | // if good chi2 then consider to add clusterCh1 |
791 | // We do not try to attach a cluster in the other chamber too since it has already been done above | |
792 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
793 | foundOneCluster = kTRUE; | |
9bf6860b | 794 | |
ea94c18b | 795 | // Printout for debuging |
796 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 797 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 |
798 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
9bf6860b | 799 | clusterCh1->Print(); |
ea94c18b | 800 | } |
801 | ||
a0dc65b4 | 802 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 803 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 804 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 805 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1); |
208f139e | 806 | fNRecTracks++; |
ea94c18b | 807 | |
808 | // Printout for debuging | |
208f139e | 809 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { |
96ebe67e | 810 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch1+1 << endl; |
208f139e | 811 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
812 | } | |
ea94c18b | 813 | |
96ebe67e | 814 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { |
815 | // keep track of the best single cluster except if a couple of clusters has already been found | |
816 | bestChi2WithOneCluster = chi2WithOneCluster; | |
817 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
208f139e | 818 | } |
ea94c18b | 819 | |
d0bfce8d | 820 | } |
ea94c18b | 821 | |
208f139e | 822 | } |
ea94c18b | 823 | |
208f139e | 824 | } |
ea94c18b | 825 | |
208f139e | 826 | // fill out the best track if required else clean up the fRecTracksPtr array |
a0dc65b4 | 827 | if (!GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 828 | if (foundTwoClusters) { |
829 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestTrackParamAtCluster2); | |
ea94c18b | 830 | |
208f139e | 831 | // Printout for debuging |
832 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 833 | cout << "FollowTrackInStation: added the two best clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 834 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 835 | } |
ea94c18b | 836 | |
96ebe67e | 837 | } else if (foundOneCluster) { |
838 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1); | |
ea94c18b | 839 | |
208f139e | 840 | // Printout for debuging |
841 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 842 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster1.GetClusterPtr()->GetChamberId()+1 << endl; |
208f139e | 843 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
04b5ea16 | 844 | } |
ea94c18b | 845 | |
dd230855 | 846 | } else { |
96ebe67e | 847 | delete [] clusterCh1Used; |
dd230855 | 848 | return kFALSE; |
849 | } | |
ea94c18b | 850 | |
96ebe67e | 851 | } else if (foundOneCluster || foundTwoClusters) { |
ea94c18b | 852 | |
853 | // remove obsolete track | |
854 | fRecTracksPtr->Remove(&trackCandidate); | |
855 | fNRecTracks--; | |
856 | ||
dd230855 | 857 | } else { |
96ebe67e | 858 | delete [] clusterCh1Used; |
dd230855 | 859 | return kFALSE; |
860 | } | |
ea94c18b | 861 | |
96ebe67e | 862 | delete [] clusterCh1Used; |
ea94c18b | 863 | return kTRUE; |
864 | ||
865 | } | |
866 | ||
867 | //__________________________________________________________________________ | |
96ebe67e | 868 | Double_t AliMUONTrackReconstructor::TryTwoClusters(const AliMUONTrackParam &trackParamAtCluster1, AliMUONVCluster* cluster2, |
869 | AliMUONTrackParam &trackParamAtCluster2) | |
ea94c18b | 870 | { |
96ebe67e | 871 | /// Test the compatibility between the track and the 2 clusters together (using trackParam's covariance matrix): |
872 | /// return the corresponding Chi2 accounting for covariances between the 2 clusters | |
873 | /// return trackParamAtCluster1 & 2 | |
ea94c18b | 874 | |
96ebe67e | 875 | // extrapolate track parameters at the z position of the second cluster (no need to extrapolate the covariances) |
876 | trackParamAtCluster2.SetParameters(trackParamAtCluster1.GetParameters()); | |
877 | trackParamAtCluster2.SetZ(trackParamAtCluster1.GetZ()); | |
878 | AliMUONTrackExtrap::ExtrapToZ(&trackParamAtCluster2, cluster2->GetZ()); | |
ea94c18b | 879 | |
96ebe67e | 880 | // set pointer to cluster2 into trackParamAtCluster2 |
881 | trackParamAtCluster2.SetClusterPtr(cluster2); | |
ea94c18b | 882 | |
96ebe67e | 883 | // Set differences between track and the 2 clusters in the bending and non bending directions |
884 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
ea94c18b | 885 | TMatrixD dPos(4,1); |
96ebe67e | 886 | dPos(0,0) = cluster1->GetX() - trackParamAtCluster1.GetNonBendingCoor(); |
887 | dPos(1,0) = cluster1->GetY() - trackParamAtCluster1.GetBendingCoor(); | |
888 | dPos(2,0) = cluster2->GetX() - trackParamAtCluster2.GetNonBendingCoor(); | |
889 | dPos(3,0) = cluster2->GetY() - trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 890 | |
96ebe67e | 891 | // Calculate the error matrix from the track parameter covariances at first cluster |
ea94c18b | 892 | TMatrixD error(4,4); |
893 | error.Zero(); | |
96ebe67e | 894 | if (trackParamAtCluster1.CovariancesExist()) { |
895 | // Save track parameters at first cluster | |
896 | TMatrixD paramAtCluster1Save(trackParamAtCluster1.GetParameters()); | |
897 | ||
898 | // Save track coordinates at second cluster | |
899 | Double_t nonBendingCoor2 = trackParamAtCluster2.GetNonBendingCoor(); | |
900 | Double_t bendingCoor2 = trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 901 | |
96ebe67e | 902 | // copy track parameters at first cluster for jacobian calculation |
903 | AliMUONTrackParam trackParam(trackParamAtCluster1); | |
ea94c18b | 904 | |
96ebe67e | 905 | // add MCS effect to the covariance matrix at first cluster |
906 | AliMUONTrackExtrap::AddMCSEffect(&trackParam,AliMUONConstants::ChamberThicknessInX0(),1.); | |
ea94c18b | 907 | |
96ebe67e | 908 | // Get the pointer to the parameter covariance matrix at first cluster |
909 | const TMatrixD& kParamCov = trackParam.GetCovariances(); | |
ea94c18b | 910 | |
911 | // Calculate the jacobian related to the transformation between track parameters | |
96ebe67e | 912 | // at first cluster and track coordinates at the 2 cluster z-positions |
ea94c18b | 913 | TMatrixD jacob(4,5); |
914 | jacob.Zero(); | |
96ebe67e | 915 | // first derivative at the first cluster: |
ea94c18b | 916 | jacob(0,0) = 1.; // dx1/dx |
917 | jacob(1,2) = 1.; // dy1/dy | |
96ebe67e | 918 | // first derivative at the second cluster: |
ea94c18b | 919 | TMatrixD dParam(5,1); |
920 | for (Int_t i=0; i<5; i++) { | |
921 | // Skip jacobian calculation for parameters with no associated error | |
922 | if (kParamCov(i,i) == 0.) continue; | |
923 | // Small variation of parameter i only | |
924 | for (Int_t j=0; j<5; j++) { | |
925 | if (j==i) { | |
926 | dParam(j,0) = TMath::Sqrt(kParamCov(i,i)); | |
96ebe67e | 927 | if (j == 4) dParam(j,0) *= TMath::Sign(1.,-paramAtCluster1Save(4,0)); // variation always in the same direction |
ea94c18b | 928 | } else dParam(j,0) = 0.; |
929 | } | |
930 | ||
96ebe67e | 931 | // Set new track parameters at first cluster |
932 | trackParam.SetParameters(paramAtCluster1Save); | |
933 | trackParam.AddParameters(dParam); | |
934 | trackParam.SetZ(cluster1->GetZ()); | |
ea94c18b | 935 | |
96ebe67e | 936 | // Extrapolate new track parameters to the z position of the second cluster |
937 | AliMUONTrackExtrap::ExtrapToZ(&trackParam,cluster2->GetZ()); | |
ea94c18b | 938 | |
939 | // Calculate the jacobian | |
96ebe67e | 940 | jacob(2,i) = (trackParam.GetNonBendingCoor() - nonBendingCoor2) / dParam(i,0); // dx2/dParami |
941 | jacob(3,i) = (trackParam.GetBendingCoor() - bendingCoor2 ) / dParam(i,0); // dy2/dParami | |
208f139e | 942 | } |
ea94c18b | 943 | |
944 | // Calculate the error matrix | |
945 | TMatrixD tmp(jacob,TMatrixD::kMult,kParamCov); | |
946 | error = TMatrixD(tmp,TMatrixD::kMultTranspose,jacob); | |
947 | } | |
948 | ||
96ebe67e | 949 | // Add cluster resolution to the error matrix |
950 | error(0,0) += cluster1->GetErrX2(); | |
951 | error(1,1) += cluster1->GetErrY2(); | |
952 | error(2,2) += cluster2->GetErrX2(); | |
953 | error(3,3) += cluster2->GetErrY2(); | |
ea94c18b | 954 | |
955 | // invert the error matrix for Chi2 calculation | |
956 | if (error.Determinant() != 0) { | |
957 | error.Invert(); | |
208f139e | 958 | } else { |
ea94c18b | 959 | AliWarning(" Determinant error=0"); |
960 | return 1.e10; | |
208f139e | 961 | } |
962 | ||
ea94c18b | 963 | // Compute the Chi2 value |
964 | TMatrixD tmp2(dPos,TMatrixD::kTransposeMult,error); | |
965 | TMatrixD result(tmp2,TMatrixD::kMult,dPos); | |
966 | ||
967 | return result(0,0); | |
968 | ||
969 | } | |
970 | ||
971 | //__________________________________________________________________________ | |
96ebe67e | 972 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster) |
ea94c18b | 973 | { |
96ebe67e | 974 | /// Add 1 cluster to the track candidate |
ea94c18b | 975 | /// Update chi2 of the track |
976 | ||
977 | // Compute local chi2 | |
96ebe67e | 978 | AliMUONVCluster* cluster = trackParamAtCluster.GetClusterPtr(); |
979 | Double_t deltaX = trackParamAtCluster.GetNonBendingCoor() - cluster->GetX(); | |
980 | Double_t deltaY = trackParamAtCluster.GetBendingCoor() - cluster->GetY(); | |
981 | Double_t localChi2 = deltaX*deltaX / cluster->GetErrX2() + | |
982 | deltaY*deltaY / cluster->GetErrY2(); | |
ea94c18b | 983 | |
96ebe67e | 984 | // Flag cluster as being not removable |
a0dc65b4 | 985 | if (GetRecoParam()->RequestStation(cluster->GetChamberId()/2)) |
9bf6860b | 986 | trackParamAtCluster.SetRemovable(kFALSE); |
987 | else trackParamAtCluster.SetRemovable(kTRUE); | |
96ebe67e | 988 | trackParamAtCluster.SetLocalChi2(0.); // --> Local chi2 not used |
5f4ceff2 | 989 | |
ea94c18b | 990 | // Update the chi2 of the new track |
96ebe67e | 991 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2); |
ea94c18b | 992 | |
96ebe67e | 993 | // Update TrackParamAtCluster |
994 | track.AddTrackParamAtCluster(trackParamAtCluster,*cluster); | |
ea94c18b | 995 | |
04b5ea16 | 996 | } |
997 | ||
de2cd600 | 998 | //__________________________________________________________________________ |
96ebe67e | 999 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster1, AliMUONTrackParam &trackParamAtCluster2) |
ea94c18b | 1000 | { |
96ebe67e | 1001 | /// Add 2 clusters to the track candidate |
ea94c18b | 1002 | /// Update track and local chi2 |
1003 | ||
96ebe67e | 1004 | // Update local chi2 at first cluster |
1005 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
1006 | Double_t deltaX = trackParamAtCluster1.GetNonBendingCoor() - cluster1->GetX(); | |
1007 | Double_t deltaY = trackParamAtCluster1.GetBendingCoor() - cluster1->GetY(); | |
1008 | Double_t localChi2AtCluster1 = deltaX*deltaX / cluster1->GetErrX2() + | |
1009 | deltaY*deltaY / cluster1->GetErrY2(); | |
1010 | trackParamAtCluster1.SetLocalChi2(localChi2AtCluster1); | |
ea94c18b | 1011 | |
96ebe67e | 1012 | // Flag first cluster as being removable |
1013 | trackParamAtCluster1.SetRemovable(kTRUE); | |
ea94c18b | 1014 | |
96ebe67e | 1015 | // Update local chi2 at second cluster |
1016 | AliMUONVCluster* cluster2 = trackParamAtCluster2.GetClusterPtr(); | |
1017 | deltaX = trackParamAtCluster2.GetNonBendingCoor() - cluster2->GetX(); | |
1018 | deltaY = trackParamAtCluster2.GetBendingCoor() - cluster2->GetY(); | |
1019 | Double_t localChi2AtCluster2 = deltaX*deltaX / cluster2->GetErrX2() + | |
1020 | deltaY*deltaY / cluster2->GetErrY2(); | |
1021 | trackParamAtCluster2.SetLocalChi2(localChi2AtCluster2); | |
ea94c18b | 1022 | |
96ebe67e | 1023 | // Flag first cluster as being removable |
1024 | trackParamAtCluster2.SetRemovable(kTRUE); | |
ea94c18b | 1025 | |
1026 | // Update the chi2 of the new track | |
96ebe67e | 1027 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2AtCluster1 + localChi2AtCluster2); |
ea94c18b | 1028 | |
96ebe67e | 1029 | // Update TrackParamAtCluster |
1030 | track.AddTrackParamAtCluster(trackParamAtCluster1,*cluster1); | |
1031 | track.AddTrackParamAtCluster(trackParamAtCluster2,*cluster2); | |
ea94c18b | 1032 | |
1033 | } | |
1034 | ||
1035 | //__________________________________________________________________________ | |
1fef78c8 | 1036 | Bool_t AliMUONTrackReconstructor::RecoverTrack(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) |
ea94c18b | 1037 | { |
1038 | /// Try to recover the track candidate in the next station | |
96ebe67e | 1039 | /// by removing the worst of the two clusters attached in the current station |
ea94c18b | 1040 | /// Return kTRUE if recovering succeeds |
1041 | AliDebug(1,"Enter RecoverTrack"); | |
1042 | ||
96ebe67e | 1043 | // Do not try to recover track until we have attached cluster(s) on station(1..) 3 |
ea94c18b | 1044 | if (nextStation > 1) return kFALSE; |
1045 | ||
96ebe67e | 1046 | Int_t worstClusterNumber = -1; |
9bf6860b | 1047 | Double_t localChi2, worstLocalChi2 = -1.; |
ea94c18b | 1048 | |
96ebe67e | 1049 | // Look for the cluster to remove |
1050 | for (Int_t clusterNumber = 0; clusterNumber < 2; clusterNumber++) { | |
1051 | AliMUONTrackParam *trackParamAtCluster = (AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(clusterNumber); | |
ea94c18b | 1052 | |
9bf6860b | 1053 | // check if current cluster is in the previous station |
1054 | if (trackParamAtCluster->GetClusterPtr()->GetChamberId()/2 != nextStation+1) break; | |
1055 | ||
96ebe67e | 1056 | // check if current cluster is removable |
1057 | if (!trackParamAtCluster->IsRemovable()) return kFALSE; | |
ea94c18b | 1058 | |
9bf6860b | 1059 | // reset the current cluster as beig not removable if it is on a required station |
a0dc65b4 | 1060 | if (GetRecoParam()->RequestStation(nextStation+1)) trackParamAtCluster->SetRemovable(kFALSE); |
9bf6860b | 1061 | |
96ebe67e | 1062 | // Pick up cluster with the worst chi2 |
1063 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
ea94c18b | 1064 | if (localChi2 > worstLocalChi2) { |
1065 | worstLocalChi2 = localChi2; | |
96ebe67e | 1066 | worstClusterNumber = clusterNumber; |
ea94c18b | 1067 | } |
9bf6860b | 1068 | |
ea94c18b | 1069 | } |
1070 | ||
9bf6860b | 1071 | // check if worst cluster found |
1072 | if (worstClusterNumber < 0) return kFALSE; | |
ea94c18b | 1073 | |
96ebe67e | 1074 | // Remove the worst cluster |
1075 | trackCandidate.RemoveTrackParamAtCluster((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(worstClusterNumber)); | |
ea94c18b | 1076 | |
1077 | // Re-fit the track: | |
1078 | // Do not take into account the multiple scattering to speed up the fit | |
1079 | // Calculate the track parameter covariance matrix | |
96ebe67e | 1080 | Fit(trackCandidate, kFALSE, kFALSE, kTRUE); |
ea94c18b | 1081 | |
96ebe67e | 1082 | // Look for new cluster(s) in next station |
1083 | return FollowTrackInStation(trackCandidate,clusterStore,nextStation); | |
ea94c18b | 1084 | |
1085 | } | |
1086 | ||
1087 | //__________________________________________________________________________ | |
96ebe67e | 1088 | void AliMUONTrackReconstructor::SetVertexErrXY2ForFit(AliMUONTrack &trackCandidate) |
de2cd600 | 1089 | { |
96ebe67e | 1090 | /// Compute the vertex resolution square from natural vertex dispersion and |
208f139e | 1091 | /// multiple scattering effets according to trackCandidate path in absorber |
1092 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
1093 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
1094 | AliDebug(1,"Enter SetVertexForFit"); | |
de2cd600 | 1095 | |
a0dc65b4 | 1096 | Double_t nonBendingReso2 = GetRecoParam()->GetNonBendingVertexDispersion() * |
1097 | GetRecoParam()->GetNonBendingVertexDispersion(); | |
1098 | Double_t bendingReso2 = GetRecoParam()->GetBendingVertexDispersion() * | |
1099 | GetRecoParam()->GetBendingVertexDispersion(); | |
96ebe67e | 1100 | |
208f139e | 1101 | // add multiple scattering effets |
96ebe67e | 1102 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate.GetTrackParamAtCluster()->First()))); |
208f139e | 1103 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering |
1104 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
ea94c18b | 1105 | const TMatrixD& kParamCov = paramAtVertex.GetCovariances(); |
1106 | nonBendingReso2 += kParamCov(0,0); | |
1107 | bendingReso2 += kParamCov(2,2); | |
96ebe67e | 1108 | |
1109 | // Set the vertex resolution square | |
1110 | trackCandidate.SetVertexErrXY2(nonBendingReso2,bendingReso2); | |
208f139e | 1111 | } |
1112 | ||
1113 | //__________________________________________________________________________ | |
96ebe67e | 1114 | void AliMUONTrackReconstructor::Fit(AliMUONTrack &track, Bool_t includeMCS, Bool_t fitWithVertex, Bool_t calcCov) |
208f139e | 1115 | { |
96ebe67e | 1116 | /// Fit the track |
1117 | /// w/wo multiple Coulomb scattering according to "includeMCS". | |
1118 | /// w/wo constraining the vertex according to "fitWithVertex". | |
1119 | /// calculating or not the covariance matrix according to "calcCov". | |
7332f213 | 1120 | AliDebug(1,"Enter Fit"); |
de2cd600 | 1121 | |
208f139e | 1122 | Double_t benC, errorParam, invBenP, nonBenC, x, y; |
de2cd600 | 1123 | AliMUONTrackParam *trackParam; |
96ebe67e | 1124 | Double_t arg[1], fedm, errdef, globalChi2; |
208f139e | 1125 | Int_t npari, nparx; |
1126 | Int_t status, covStatus; | |
1127 | ||
8cde4af5 | 1128 | // Instantiate gMinuit if not already done |
1129 | if (!gMinuit) gMinuit = new TMinuit(6); | |
208f139e | 1130 | // Clear MINUIT parameters |
1131 | gMinuit->mncler(); | |
1132 | // Give the fitted track to MINUIT | |
ea94c18b | 1133 | gMinuit->SetObjectFit(&track); |
208f139e | 1134 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { |
1135 | // Define print level | |
1136 | arg[0] = 1; | |
1137 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1138 | // Print covariance matrix | |
1139 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
1140 | } else { | |
1141 | arg[0] = -1; | |
1142 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1143 | } | |
de2cd600 | 1144 | // No warnings |
208f139e | 1145 | gMinuit->mnexcm("SET NOW", arg, 0, status); |
1146 | // Define strategy | |
1147 | //arg[0] = 2; | |
1148 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
1149 | ||
ea94c18b | 1150 | // set flag w/wo multiple scattering according to "includeMCS" |
96ebe67e | 1151 | track.FitWithMCS(includeMCS); |
ea94c18b | 1152 | if (includeMCS) { |
96ebe67e | 1153 | // compute cluster weights only once |
1154 | if (!track.ComputeClusterWeights()) { | |
ea94c18b | 1155 | AliWarning("cannot take into account the multiple scattering effects"); |
96ebe67e | 1156 | track.FitWithMCS(kFALSE); |
ea94c18b | 1157 | } |
1158 | } | |
1159 | ||
96ebe67e | 1160 | track.FitWithVertex(fitWithVertex); |
1161 | if (fitWithVertex) SetVertexErrXY2ForFit(track); | |
1162 | ||
ea94c18b | 1163 | // Set fitting function |
1164 | gMinuit->SetFCN(TrackChi2); | |
208f139e | 1165 | |
1166 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
9bf6860b | 1167 | // Mandatory limits to avoid NaN values of parameters |
96ebe67e | 1168 | trackParam = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->First()); |
a0dc65b4 | 1169 | Double_t maxIBM = 1. / GetRecoParam()->GetMinBendingMomentum(); |
208f139e | 1170 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); |
9bf6860b | 1171 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -1., 1., status); |
208f139e | 1172 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); |
9bf6860b | 1173 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -1.5, 1.5, status); |
1174 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -maxIBM, maxIBM, status); | |
208f139e | 1175 | |
de2cd600 | 1176 | // minimization |
208f139e | 1177 | gMinuit->mnexcm("MIGRAD", arg, 0, status); |
1178 | ||
1179 | // Calculate the covariance matrix more accurately if required | |
1180 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
8cde4af5 | 1181 | |
de2cd600 | 1182 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") |
208f139e | 1183 | gMinuit->GetParameter(0, x, errorParam); |
1184 | trackParam->SetNonBendingCoor(x); | |
1185 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
de2cd600 | 1186 | trackParam->SetNonBendingSlope(nonBenC); |
208f139e | 1187 | gMinuit->GetParameter(2, y, errorParam); |
1188 | trackParam->SetBendingCoor(y); | |
1189 | gMinuit->GetParameter(3, benC, errorParam); | |
1190 | trackParam->SetBendingSlope(benC); | |
1191 | gMinuit->GetParameter(4, invBenP, errorParam); | |
1192 | trackParam->SetInverseBendingMomentum(invBenP); | |
1193 | ||
de2cd600 | 1194 | // global result of the fit |
96ebe67e | 1195 | gMinuit->mnstat(globalChi2, fedm, errdef, npari, nparx, covStatus); |
1196 | track.SetGlobalChi2(globalChi2); | |
208f139e | 1197 | |
1198 | // Get the covariance matrix if required | |
1199 | if (calcCov) { | |
1200 | // Covariance matrix according to HESSE status | |
1201 | // If problem then keep only the diagonal terms (variances) | |
1202 | Double_t matrix[5][5]; | |
1203 | gMinuit->mnemat(&matrix[0][0],5); | |
1204 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
1205 | else trackParam->SetVariances(matrix); | |
ea94c18b | 1206 | } else trackParam->DeleteCovariances(); |
208f139e | 1207 | |
de2cd600 | 1208 | } |
1209 | ||
1210 | //__________________________________________________________________________ | |
ea94c18b | 1211 | void TrackChi2(Int_t & /*nParam*/, Double_t * /*gradient*/, Double_t &chi2, Double_t *param, Int_t /*flag*/) |
de2cd600 | 1212 | { |
ea94c18b | 1213 | /// Return the "Chi2" to be minimized with Minuit for track fitting. |
96ebe67e | 1214 | /// Assumes that the trackParamAtCluster are sorted according to increasing Z. |
1215 | /// Track parameters at each cluster are updated accordingly. | |
ea94c18b | 1216 | /// Vertex is used according to the flag "trackBeingFitted->GetFitWithVertex()". |
1217 | /// Multiple Coulomb scattering is taken into account according to the flag "trackBeingFitted->GetFitWithMCS()". | |
208f139e | 1218 | |
1219 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
96ebe67e | 1220 | AliMUONTrackParam* trackParamAtCluster = (AliMUONTrackParam*) trackBeingFitted->GetTrackParamAtCluster()->First(); |
208f139e | 1221 | Double_t dX, dY; |
ea94c18b | 1222 | chi2 = 0.; // initialize chi2 |
208f139e | 1223 | |
ea94c18b | 1224 | // update track parameters |
96ebe67e | 1225 | trackParamAtCluster->SetNonBendingCoor(param[0]); |
1226 | trackParamAtCluster->SetNonBendingSlope(param[1]); | |
1227 | trackParamAtCluster->SetBendingCoor(param[2]); | |
1228 | trackParamAtCluster->SetBendingSlope(param[3]); | |
1229 | trackParamAtCluster->SetInverseBendingMomentum(param[4]); | |
1230 | trackBeingFitted->UpdateTrackParamAtCluster(); | |
208f139e | 1231 | |
1232 | // Take the vertex into account in the fit if required | |
96ebe67e | 1233 | if (trackBeingFitted->FitWithVertex()) { |
1234 | Double_t nonBendingReso2,bendingReso2; | |
1235 | trackBeingFitted->GetVertexErrXY2(nonBendingReso2,bendingReso2); | |
1236 | if (nonBendingReso2 == 0. || bendingReso2 == 0.) chi2 += 1.e10; | |
1237 | else { | |
1238 | AliMUONTrackParam paramAtVertex(*trackParamAtCluster); | |
1239 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); // vextex position = (0,0,0) | |
1240 | dX = paramAtVertex.GetNonBendingCoor(); | |
1241 | dY = paramAtVertex.GetBendingCoor(); | |
1242 | chi2 += dX * dX / nonBendingReso2 + dY * dY / bendingReso2; | |
208f139e | 1243 | } |
de2cd600 | 1244 | } |
208f139e | 1245 | |
ea94c18b | 1246 | // compute chi2 w/wo multiple scattering |
96ebe67e | 1247 | chi2 += trackBeingFitted->ComputeGlobalChi2(trackBeingFitted->FitWithMCS()); |
b709ac13 | 1248 | |
1249 | } | |
1250 | ||
1251 | //__________________________________________________________________________ | |
96ebe67e | 1252 | void AliMUONTrackReconstructor::ComplementTracks(const AliMUONVClusterStore& clusterStore) |
b709ac13 | 1253 | { |
1254 | /// Complete tracks by adding missing clusters (if there is an overlap between | |
1255 | /// two detection elements, the track may have two clusters in the same chamber) | |
1256 | /// Re-fit track parameters and covariances | |
1257 | AliDebug(1,"Enter ComplementTracks"); | |
1258 | ||
1259 | Int_t chamberId, detElemId; | |
96ebe67e | 1260 | Double_t chi2OfCluster, bestChi2OfCluster; |
a0dc65b4 | 1261 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * |
1262 | GetRecoParam()->GetSigmaCutForTracking(); | |
96ebe67e | 1263 | Bool_t foundOneCluster, trackModified; |
1264 | AliMUONVCluster* cluster; | |
1265 | AliMUONTrackParam *trackParam, *nextTrackParam, copyOfTrackParam, trackParamAtCluster, bestTrackParamAtCluster; | |
b709ac13 | 1266 | |
b709ac13 | 1267 | AliMUONTrack *track = (AliMUONTrack*) fRecTracksPtr->First(); |
1268 | while (track) { | |
1269 | trackModified = kFALSE; | |
1270 | ||
96ebe67e | 1271 | trackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->First(); |
b709ac13 | 1272 | while (trackParam) { |
96ebe67e | 1273 | foundOneCluster = kFALSE; |
1274 | bestChi2OfCluster = 2. * sigmaCut2; // 2 because 2 quantities in chi2 | |
1275 | chamberId = trackParam->GetClusterPtr()->GetChamberId(); | |
1276 | detElemId = trackParam->GetClusterPtr()->GetDetElemId(); | |
b709ac13 | 1277 | |
1278 | // prepare nextTrackParam before adding new cluster because of the sorting | |
96ebe67e | 1279 | nextTrackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 1280 | |
1281 | // recover track parameters from local fit and put them into a copy of trackParam | |
1282 | copyOfTrackParam.SetZ(trackParam->GetZ()); | |
1283 | copyOfTrackParam.SetParameters(trackParam->GetSmoothParameters()); | |
1284 | copyOfTrackParam.SetCovariances(trackParam->GetSmoothCovariances()); | |
1285 | ||
96ebe67e | 1286 | // Create iterators to loop over clusters in current chamber |
1287 | TIter nextInCh(clusterStore.CreateChamberIterator(chamberId,chamberId)); | |
1288 | ||
b709ac13 | 1289 | // look for one second candidate in the same chamber |
96ebe67e | 1290 | while ( ( cluster = static_cast<AliMUONVCluster*>(nextInCh()) ) ) { |
b709ac13 | 1291 | |
1292 | // look for a cluster in another detection element | |
96ebe67e | 1293 | if (cluster->GetDetElemId() == detElemId) continue; |
b709ac13 | 1294 | |
96ebe67e | 1295 | // try to add the current cluster fast |
1296 | if (!TryOneClusterFast(copyOfTrackParam, cluster)) continue; | |
b709ac13 | 1297 | |
96ebe67e | 1298 | // try to add the current cluster accurately |
1299 | chi2OfCluster = TryOneCluster(copyOfTrackParam, cluster, trackParamAtCluster); | |
b709ac13 | 1300 | |
1301 | // if better chi2 then prepare to add this cluster to the track | |
96ebe67e | 1302 | if (chi2OfCluster < bestChi2OfCluster) { |
1303 | bestChi2OfCluster = chi2OfCluster; | |
1304 | bestTrackParamAtCluster = trackParamAtCluster; | |
1305 | foundOneCluster = kTRUE; | |
b709ac13 | 1306 | } |
1307 | ||
1308 | } | |
1309 | ||
1310 | // add new cluster if any | |
96ebe67e | 1311 | if (foundOneCluster) { |
0e894e58 | 1312 | |
1313 | // Printout for debuging | |
1314 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1315 | cout << "ComplementTracks: found one cluster in chamber(1..): " << chamberId+1 << endl; | |
1316 | bestTrackParamAtCluster.GetClusterPtr()->Print(); | |
1317 | cout<<endl<<"Track parameters and covariances at cluster:"<<endl; | |
1318 | bestTrackParamAtCluster.GetParameters().Print(); | |
1319 | bestTrackParamAtCluster.GetCovariances().Print(); | |
1320 | } | |
1321 | ||
7332f213 | 1322 | trackParam->SetRemovable(kTRUE); |
1323 | bestTrackParamAtCluster.SetRemovable(kTRUE); | |
1324 | track->AddTrackParamAtCluster(bestTrackParamAtCluster,*(bestTrackParamAtCluster.GetClusterPtr())); | |
b709ac13 | 1325 | trackModified = kTRUE; |
1326 | } | |
1327 | ||
1328 | trackParam = nextTrackParam; | |
1329 | } | |
1330 | ||
1331 | // re-fit track parameters if needed | |
96ebe67e | 1332 | if (trackModified) Fit(*track, kTRUE, kFALSE, kTRUE); |
b709ac13 | 1333 | |
1334 | track = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1335 | } | |
ea94c18b | 1336 | |
de2cd600 | 1337 | } |
1338 | ||
1339 | //__________________________________________________________________________ | |
7332f213 | 1340 | void AliMUONTrackReconstructor::ImproveTrack(AliMUONTrack &track) |
de2cd600 | 1341 | { |
7332f213 | 1342 | /// Improve the given track by removing clusters with local chi2 highter than the defined cut |
ea94c18b | 1343 | /// Recompute track parameters and covariances at the remaining clusters |
7332f213 | 1344 | AliDebug(1,"Enter ImproveTrack"); |
208f139e | 1345 | |
ea94c18b | 1346 | Double_t localChi2, worstLocalChi2; |
7332f213 | 1347 | AliMUONTrackParam *trackParamAtCluster, *worstTrackParamAtCluster; |
a0dc65b4 | 1348 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForImprovement() * |
1349 | GetRecoParam()->GetSigmaCutForImprovement(); | |
208f139e | 1350 | |
7332f213 | 1351 | while (!track.IsImproved()) { |
ea94c18b | 1352 | |
7332f213 | 1353 | // identify removable clusters |
a0dc65b4 | 1354 | track.TagRemovableClusters(GetRecoParam()->RequestedStationMask()); |
b709ac13 | 1355 | |
7332f213 | 1356 | // Update track parameters and covariances |
1357 | track.UpdateCovTrackParamAtCluster(); | |
1358 | ||
1359 | // Compute local chi2 of each clusters | |
1360 | track.ComputeLocalChi2(kTRUE); | |
1361 | ||
1362 | // Look for the cluster to remove | |
1363 | worstTrackParamAtCluster = NULL; | |
1364 | worstLocalChi2 = 0.; | |
1365 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1366 | while (trackParamAtCluster) { | |
ea94c18b | 1367 | |
7332f213 | 1368 | // Pick up cluster with the worst chi2 |
1369 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1370 | if (localChi2 > worstLocalChi2) { | |
1371 | worstLocalChi2 = localChi2; | |
1372 | worstTrackParamAtCluster = trackParamAtCluster; | |
ea94c18b | 1373 | } |
1374 | ||
7332f213 | 1375 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(trackParamAtCluster); |
1376 | } | |
1377 | ||
1378 | // Check if worst cluster found | |
1379 | if (!worstTrackParamAtCluster) { | |
1380 | AliWarning("Bad local chi2 values?"); | |
1381 | break; | |
1382 | } | |
1383 | ||
1384 | // Check whether the worst chi2 is under requirement or not | |
1385 | if (worstLocalChi2 < 2. * sigmaCut2) { // 2 because 2 quantities in chi2 | |
1386 | track.SetImproved(kTRUE); | |
1387 | break; | |
1388 | } | |
1389 | ||
1390 | // if the worst cluster is not removable then stop improvement | |
1391 | if (!worstTrackParamAtCluster->IsRemovable()) break; | |
1392 | ||
1393 | // Remove the worst cluster | |
1394 | track.RemoveTrackParamAtCluster(worstTrackParamAtCluster); | |
1395 | ||
1396 | // Re-fit the track: | |
1397 | // Take into account the multiple scattering | |
1398 | // Calculate the track parameter covariance matrix | |
1399 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1400 | ||
1401 | // Printout for debuging | |
1402 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1403 | cout << "ImproveTracks: track " << fRecTracksPtr->IndexOf(&track)+1 << " improved " << endl; | |
de2cd600 | 1404 | } |
ea94c18b | 1405 | |
de2cd600 | 1406 | } |
1407 | ||
de2cd600 | 1408 | } |
1409 | ||
208f139e | 1410 | //__________________________________________________________________________ |
7332f213 | 1411 | void AliMUONTrackReconstructor::FinalizeTrack(AliMUONTrack &track) |
b8dc484b | 1412 | { |
7332f213 | 1413 | /// Recompute track parameters and covariances at each attached cluster |
1414 | /// from those at the first one, if not already done | |
1415 | AliDebug(1,"Enter FinalizeTrack"); | |
1416 | if (!track.IsImproved()) track.UpdateCovTrackParamAtCluster(); | |
a9e2aefa | 1417 | } |
1418 | ||
9bf6860b | 1419 | //__________________________________________________________________________ |
b1fea02e | 1420 | Bool_t AliMUONTrackReconstructor::RefitTrack(AliMUONTrack &track, Bool_t enableImprovement) |
7deb8eb0 | 1421 | { |
1422 | /// re-fit the given track | |
1423 | ||
1424 | // check validity of the track | |
ad3c6eda | 1425 | if (track.GetNClusters() < 3) { |
7deb8eb0 | 1426 | AliWarning("the track does not contain enough clusters --> unable to refit"); |
1427 | return kFALSE; | |
1428 | } | |
1429 | ||
1430 | // reset the seed (i.e. parameters at first cluster) before fitting | |
1431 | AliMUONTrackParam* firstTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1432 | if (firstTrackParam->GetInverseBendingMomentum() == 0.) { | |
1433 | AliWarning("track parameters at first chamber are not initialized --> unable to refit"); | |
1434 | return kFALSE; | |
1435 | } | |
1436 | ||
1437 | // compute track parameters at each cluster from parameters at the first one | |
1438 | // necessary to compute multiple scattering effect during refitting | |
1439 | track.UpdateTrackParamAtCluster(); | |
1440 | ||
1441 | // Re-fit the track: | |
1442 | // Take into account the multiple scattering | |
1443 | // Calculate the track parameter covariance matrix | |
1444 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1445 | ||
1446 | // Improve the reconstructed tracks if required | |
b1fea02e | 1447 | track.SetImproved(kFALSE); |
a0dc65b4 | 1448 | if (enableImprovement && GetRecoParam()->ImproveTracks()) ImproveTrack(track); |
7deb8eb0 | 1449 | |
1450 | // Fill AliMUONTrack data members | |
1451 | FinalizeTrack(track); | |
1452 | ||
1453 | return kTRUE; | |
1454 | ||
1455 | } | |
1456 |