1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 ////////////////////////////////////////////////////////////////////////////
20 // The TRD offline tracklet
22 // The running horse of the TRD reconstruction. The following tasks are preformed:
23 // 1. Clusters attachment to tracks based on prior information stored at tracklet level (see AttachClusters)
24 // 2. Clusters position recalculation based on track information (see GetClusterXY and Fit)
25 // 3. Cluster error parametrization recalculation (see Fit)
26 // 4. Linear track approximation (Fit)
27 // 5. Optimal position (including z estimate for pad row cross tracklets) and covariance matrix of the track fit inside one TRD chamber (Fit)
28 // 6. Tilt pad correction and systematic effects (GetCovAt)
29 // 7. dEdx calculation (CookdEdx)
30 // 8. PID probabilities estimation (CookPID)
33 // Alex Bercuci <A.Bercuci@gsi.de> //
34 // Markus Fasel <M.Fasel@gsi.de> //
36 ////////////////////////////////////////////////////////////////////////////
39 #include "TLinearFitter.h"
40 #include "TClonesArray.h" // tmp
41 #include <TTreeStream.h>
44 #include "AliMathBase.h"
45 #include "AliCDBManager.h"
46 #include "AliTracker.h"
48 #include "AliTRDpadPlane.h"
49 #include "AliTRDcluster.h"
50 #include "AliTRDseedV1.h"
51 #include "AliTRDtrackV1.h"
52 #include "AliTRDcalibDB.h"
53 #include "AliTRDchamberTimeBin.h"
54 #include "AliTRDtrackingChamber.h"
55 #include "AliTRDtrackerV1.h"
56 #include "AliTRDrecoParam.h"
57 #include "AliTRDCommonParam.h"
59 #include "Cal/AliTRDCalPID.h"
60 #include "Cal/AliTRDCalROC.h"
61 #include "Cal/AliTRDCalDet.h"
63 ClassImp(AliTRDseedV1)
65 TLinearFitter *AliTRDseedV1::fgFitterY = NULL;
66 TLinearFitter *AliTRDseedV1::fgFitterZ = NULL;
68 //____________________________________________________________________
69 AliTRDseedV1::AliTRDseedV1(Int_t det)
71 ,fkReconstructor(NULL)
97 memset(fIndexes,0xFF,kNclusters*sizeof(fIndexes[0]));
98 memset(fClusters, 0, kNclusters*sizeof(AliTRDcluster*));
99 memset(fPad, 0, 3*sizeof(Float_t));
100 fYref[0] = 0.; fYref[1] = 0.;
101 fZref[0] = 0.; fZref[1] = 0.;
102 fYfit[0] = 0.; fYfit[1] = 0.;
103 fZfit[0] = 0.; fZfit[1] = 0.;
104 memset(fdEdx, 0, kNslices*sizeof(Float_t));
105 for(int ispec=0; ispec<AliPID::kSPECIES; ispec++) fProb[ispec] = -1.;
106 fLabels[0]=-1; fLabels[1]=-1; // most freq MC labels
107 fLabels[2]=0; // number of different labels for tracklet
108 memset(fRefCov, 0, 7*sizeof(Double_t));
109 // covariance matrix [diagonal]
110 // default sy = 200um and sz = 2.3 cm
111 fCov[0] = 4.e-4; fCov[1] = 0.; fCov[2] = 5.3;
112 SetStandAlone(kFALSE);
115 //____________________________________________________________________
116 AliTRDseedV1::AliTRDseedV1(const AliTRDseedV1 &ref)
117 :AliTRDtrackletBase((AliTRDtrackletBase&)ref)
118 ,fkReconstructor(NULL)
142 // Copy Constructor performing a deep copy
147 SetBit(kOwner, kFALSE);
148 SetStandAlone(ref.IsStandAlone());
152 //____________________________________________________________________
153 AliTRDseedV1& AliTRDseedV1::operator=(const AliTRDseedV1 &ref)
156 // Assignment Operator using the copy function
162 SetBit(kOwner, kFALSE);
167 //____________________________________________________________________
168 AliTRDseedV1::~AliTRDseedV1()
171 // Destructor. The RecoParam object belongs to the underlying tracker.
174 //printf("I-AliTRDseedV1::~AliTRDseedV1() : Owner[%s]\n", IsOwner()?"YES":"NO");
177 for(int itb=0; itb<kNclusters; itb++){
178 if(!fClusters[itb]) continue;
179 //AliInfo(Form("deleting c %p @ %d", fClusters[itb], itb));
180 delete fClusters[itb];
181 fClusters[itb] = NULL;
186 //____________________________________________________________________
187 void AliTRDseedV1::Copy(TObject &ref) const
194 AliTRDseedV1 &target = (AliTRDseedV1 &)ref;
196 target.fkReconstructor = fkReconstructor;
197 target.fClusterIter = NULL;
201 target.fS2PRF = fS2PRF;
202 target.fDiffL = fDiffL;
203 target.fDiffT = fDiffT;
204 target.fClusterIdx = 0;
205 target.fErrorMsg = fErrorMsg;
217 target.fChi2 = fChi2;
219 memcpy(target.fIndexes, fIndexes, kNclusters*sizeof(Int_t));
220 memcpy(target.fClusters, fClusters, kNclusters*sizeof(AliTRDcluster*));
221 memcpy(target.fPad, fPad, 3*sizeof(Float_t));
222 target.fYref[0] = fYref[0]; target.fYref[1] = fYref[1];
223 target.fZref[0] = fZref[0]; target.fZref[1] = fZref[1];
224 target.fYfit[0] = fYfit[0]; target.fYfit[1] = fYfit[1];
225 target.fZfit[0] = fZfit[0]; target.fZfit[1] = fZfit[1];
226 memcpy(target.fdEdx, fdEdx, kNslices*sizeof(Float_t));
227 memcpy(target.fProb, fProb, AliPID::kSPECIES*sizeof(Float_t));
228 memcpy(target.fLabels, fLabels, 3*sizeof(Int_t));
229 memcpy(target.fRefCov, fRefCov, 7*sizeof(Double_t));
230 memcpy(target.fCov, fCov, 3*sizeof(Double_t));
236 //____________________________________________________________
237 Bool_t AliTRDseedV1::Init(AliTRDtrackV1 *track)
239 // Initialize this tracklet using the track information
242 // track - the TRD track used to initialize the tracklet
244 // Detailed description
245 // The function sets the starting point and direction of the
246 // tracklet according to the information from the TRD track.
249 // The TRD track has to be propagated to the beginning of the
250 // chamber where the tracklet will be constructed
254 if(!track->GetProlongation(fX0, y, z)) return kFALSE;
260 //_____________________________________________________________________________
261 void AliTRDseedV1::Reset()
266 fExB=0.;fVD=0.;fT0=0.;fS2PRF=0.;
273 fdX=0.;fX0=0.; fX=0.; fY=0.; fZ=0.;
277 for(Int_t ic=kNclusters; ic--;) fIndexes[ic] = -1;
278 memset(fClusters, 0, kNclusters*sizeof(AliTRDcluster*));
279 memset(fPad, 0, 3*sizeof(Float_t));
280 fYref[0] = 0.; fYref[1] = 0.;
281 fZref[0] = 0.; fZref[1] = 0.;
282 fYfit[0] = 0.; fYfit[1] = 0.;
283 fZfit[0] = 0.; fZfit[1] = 0.;
284 memset(fdEdx, 0, kNslices*sizeof(Float_t));
285 for(int ispec=0; ispec<AliPID::kSPECIES; ispec++) fProb[ispec] = -1.;
286 fLabels[0]=-1; fLabels[1]=-1; // most freq MC labels
287 fLabels[2]=0; // number of different labels for tracklet
288 memset(fRefCov, 0, 7*sizeof(Double_t));
289 // covariance matrix [diagonal]
290 // default sy = 200um and sz = 2.3 cm
291 fCov[0] = 4.e-4; fCov[1] = 0.; fCov[2] = 5.3;
294 //____________________________________________________________________
295 void AliTRDseedV1::Update(const AliTRDtrackV1 *trk)
297 // update tracklet reference position from the TRD track
299 Double_t fSnp = trk->GetSnp();
300 Double_t fTgl = trk->GetTgl();
302 Double_t norm =1./TMath::Sqrt(1. - fSnp*fSnp);
303 fYref[1] = fSnp*norm;
304 fZref[1] = fTgl*norm;
305 SetCovRef(trk->GetCovariance());
307 Double_t dx = trk->GetX() - fX0;
308 fYref[0] = trk->GetY() - dx*fYref[1];
309 fZref[0] = trk->GetZ() - dx*fZref[1];
312 //_____________________________________________________________________________
313 void AliTRDseedV1::UpdateUsed()
316 // Calculate number of used clusers in the tracklet
319 Int_t nused = 0, nshared = 0;
320 for (Int_t i = kNclusters; i--; ) {
321 if (!fClusters[i]) continue;
322 if(fClusters[i]->IsUsed()){
324 } else if(fClusters[i]->IsShared()){
325 if(IsStandAlone()) nused++;
333 //_____________________________________________________________________________
334 void AliTRDseedV1::UseClusters()
339 // In stand alone mode:
340 // Clusters which are marked as used or shared from another track are
341 // removed from the tracklet
344 // - Clusters which are used by another track become shared
345 // - Clusters which are attached to a kink track become shared
347 AliTRDcluster **c = &fClusters[0];
348 for (Int_t ic=kNclusters; ic--; c++) {
351 if((*c)->IsShared() || (*c)->IsUsed()){
352 if((*c)->IsShared()) SetNShared(GetNShared()-1);
353 else SetNUsed(GetNUsed()-1);
360 if((*c)->IsUsed() || IsKink()){
371 //____________________________________________________________________
372 void AliTRDseedV1::CookdEdx(Int_t nslices)
374 // Calculates average dE/dx for all slices and store them in the internal array fdEdx.
377 // nslices : number of slices for which dE/dx should be calculated
379 // store results in the internal array fdEdx. This can be accessed with the method
380 // AliTRDseedV1::GetdEdx()
382 // Detailed description
383 // Calculates average dE/dx for all slices. Depending on the PID methode
384 // the number of slices can be 3 (LQ) or 8(NN).
385 // The calculation of dQ/dl are done using the tracklet fit results (see AliTRDseedV1::GetdQdl(Int_t))
387 // The following effects are included in the calculation:
388 // 1. calibration values for t0 and vdrift (using x coordinate to calculate slice)
389 // 2. cluster sharing (optional see AliTRDrecoParam::SetClusterSharing())
393 Int_t nclusters[kNslices];
394 memset(nclusters, 0, kNslices*sizeof(Int_t));
395 memset(fdEdx, 0, kNslices*sizeof(Float_t));
397 const Double_t kDriftLength = (.5 * AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
399 AliTRDcluster *c = NULL;
400 for(int ic=0; ic<AliTRDtrackerV1::GetNTimeBins(); ic++){
401 if(!(c = fClusters[ic]) && !(c = fClusters[ic+kNtb])) continue;
402 Float_t dx = TMath::Abs(fX0 - c->GetX());
404 // Filter clusters for dE/dx calculation
406 // 1.consider calibration effects for slice determination
408 if(dx<kDriftLength){ // TODO should be replaced by c->IsInChamber()
409 slice = Int_t(dx * nslices / kDriftLength);
410 } else slice = c->GetX() < fX0 ? nslices-1 : 0;
413 // 2. take sharing into account
414 Float_t w = /*c->IsShared() ? .5 :*/ 1.;
416 // 3. take into account large clusters TODO
417 //w *= c->GetNPads() > 3 ? .8 : 1.;
420 fdEdx[slice] += w * GetdQdl(ic); //fdQdl[ic];
422 } // End of loop over clusters
424 //if(fkReconstructor->GetPIDMethod() == AliTRDReconstructor::kLQPID){
425 if(nslices == AliTRDpidUtil::kLQslices){
426 // calculate mean charge per slice (only LQ PID)
427 for(int is=0; is<nslices; is++){
428 if(nclusters[is]) fdEdx[is] /= nclusters[is];
433 //_____________________________________________________________________________
434 void AliTRDseedV1::CookLabels()
437 // Cook 2 labels for seed
443 for (Int_t i = 0; i < kNclusters; i++) {
444 if (!fClusters[i]) continue;
445 for (Int_t ilab = 0; ilab < 3; ilab++) {
446 if (fClusters[i]->GetLabel(ilab) >= 0) {
447 labels[nlab] = fClusters[i]->GetLabel(ilab);
453 fLabels[2] = AliMathBase::Freq(nlab,labels,out,kTRUE);
455 if ((fLabels[2] > 1) && (out[3] > 1)) fLabels[1] = out[2];
459 //____________________________________________________________________
460 Float_t AliTRDseedV1::GetdQdl(Int_t ic, Float_t *dl) const
462 // Using the linear approximation of the track inside one TRD chamber (TRD tracklet)
463 // the charge per unit length can be written as:
465 // #frac{dq}{dl} = #frac{q_{c}}{dx * #sqrt{1 + #(){#frac{dy}{dx}}^{2}_{fit} + #(){#frac{dz}{dx}}^{2}_{ref}}}
467 // where qc is the total charge collected in the current time bin and dx is the length
469 // The following correction are applied :
470 // - charge : pad row cross corrections
471 // [diffusion and TRF assymetry] TODO
472 // - dx : anisochronity, track inclination - see Fit and AliTRDcluster::GetXloc()
473 // and AliTRDcluster::GetYloc() for the effects taken into account
476 //<img src="TRD/trackletDQDT.gif">
478 // In the picture the energy loss measured on the tracklet as a function of drift time [left] and respectively
479 // drift length [right] for different particle species is displayed.
480 // Author : Alex Bercuci <A.Bercuci@gsi.de>
483 // check whether both clusters are inside the chamber
484 Bool_t hasClusterInChamber = kFALSE;
485 if(fClusters[ic] && fClusters[ic]->IsInChamber()){
486 hasClusterInChamber = kTRUE;
487 dq += TMath::Abs(fClusters[ic]->GetQ());
488 }else if(fClusters[ic+kNtb] && fClusters[ic+kNtb]->IsInChamber()){
489 hasClusterInChamber = kTRUE;
490 dq += TMath::Abs(fClusters[ic+kNtb]->GetQ());
492 if(!hasClusterInChamber) return 0.;
493 if(dq<1.e-3) return 0.;
496 if(ic-1>=0 && ic+1<kNtb){
497 Float_t x2(0.), x1(0.);
498 // try to estimate upper radial position (find the cluster which is inside the chamber)
499 if(fClusters[ic-1] && fClusters[ic-1]->IsInChamber()) x2 = fClusters[ic-1]->GetX();
500 else if(fClusters[ic-1+kNtb] && fClusters[ic-1+kNtb]->IsInChamber()) x2 = fClusters[ic-1+kNtb]->GetX();
501 else if(fClusters[ic] && fClusters[ic]->IsInChamber()) x2 = fClusters[ic]->GetX()+fdX;
502 else x2 = fClusters[ic+kNtb]->GetX()+fdX;
503 // try to estimate lower radial position (find the cluster which is inside the chamber)
504 if(fClusters[ic+1] && fClusters[ic+1]->IsInChamber()) x1 = fClusters[ic+1]->GetX();
505 else if(fClusters[ic+1+kNtb] && fClusters[ic+1+kNtb]->IsInChamber()) x1 = fClusters[ic+1+kNtb]->GetX();
506 else if(fClusters[ic] && fClusters[ic]->IsInChamber()) x1 = fClusters[ic]->GetX()-fdX;
507 else x1 = fClusters[ic+kNtb]->GetX()-fdX;
511 dx *= TMath::Sqrt(1. + fYfit[1]*fYfit[1] + fZref[1]*fZref[1]);
516 //____________________________________________________________
517 Float_t AliTRDseedV1::GetMomentum(Float_t *err) const
519 // Returns momentum of the track after update with the current tracklet as:
521 // p=#frac{1}{1/p_{t}} #sqrt{1+tgl^{2}}
523 // and optionally the momentum error (if err is not null).
524 // The estimated variance of the momentum is given by:
526 // #sigma_{p}^{2} = (#frac{dp}{dp_{t}})^{2} #sigma_{p_{t}}^{2}+(#frac{dp}{dtgl})^{2} #sigma_{tgl}^{2}+2#frac{dp}{dp_{t}}#frac{dp}{dtgl} cov(tgl,1/p_{t})
528 // which can be simplified to
530 // #sigma_{p}^{2} = p^{2}p_{t}^{4}tgl^{2}#sigma_{tgl}^{2}-2p^{2}p_{t}^{3}tgl cov(tgl,1/p_{t})+p^{2}p_{t}^{2}#sigma_{1/p_{t}}^{2}
534 Double_t p = fPt*TMath::Sqrt(1.+fZref[1]*fZref[1]);
536 Double_t tgl2 = fZref[1]*fZref[1];
537 Double_t pt2 = fPt*fPt;
540 p2*tgl2*pt2*pt2*fRefCov[4]
541 -2.*p2*fZref[1]*fPt*pt2*fRefCov[5]
543 (*err) = TMath::Sqrt(s2);
549 //____________________________________________________________________
550 Float_t* AliTRDseedV1::GetProbability(Bool_t force)
552 if(!force) return &fProb[0];
553 if(!CookPID()) return NULL;
557 //____________________________________________________________
558 Bool_t AliTRDseedV1::CookPID()
560 // Fill probability array for tracklet from the DB.
565 // returns pointer to the probability array and NULL if missing DB access
567 // Retrieve PID probabilities for e+-, mu+-, K+-, pi+- and p+- from the DB according to tracklet information:
568 // - estimated momentum at tracklet reference point
569 // - dE/dx measurements
572 // According to the steering settings specified in the reconstruction one of the following methods are used
573 // - Neural Network [default] - option "nn"
574 // - 2D Likelihood - option "!nn"
576 AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
578 AliError("No access to calibration data");
582 if (!fkReconstructor) {
583 AliError("Reconstructor not set.");
587 // Retrieve the CDB container class with the parametric detector response
588 const AliTRDCalPID *pd = calibration->GetPIDObject(fkReconstructor->GetPIDMethod());
590 AliError("No access to AliTRDCalPID object");
593 //AliInfo(Form("Method[%d] : %s", fkReconstructor->GetRecoParam() ->GetPIDMethod(), pd->IsA()->GetName()));
595 // calculate tracklet length TO DO
596 Float_t length = (AliTRDgeometry::AmThick() + AliTRDgeometry::DrThick());
597 /// TMath::Sqrt((1.0 - fSnp[iPlane]*fSnp[iPlane]) / (1.0 + fTgl[iPlane]*fTgl[iPlane]));
600 CookdEdx(fkReconstructor->GetNdEdxSlices());
602 // Sets the a priori probabilities
603 for(int ispec=0; ispec<AliPID::kSPECIES; ispec++)
604 fProb[ispec] = pd->GetProbability(ispec, GetMomentum(), &fdEdx[0], length, GetPlane());
609 //____________________________________________________________________
610 Float_t AliTRDseedV1::GetQuality(Bool_t kZcorr) const
613 // Returns a quality measurement of the current seed
616 Float_t zcorr = kZcorr ? GetTilt() * (fZfit[0] - fZref[0]) : 0.;
618 .5 * TMath::Abs(18.0 - GetN())
619 + 10.* TMath::Abs(fYfit[1] - fYref[1])
620 + 5. * TMath::Abs(fYfit[0] - fYref[0] + zcorr)
621 + 2. * TMath::Abs(fZfit[0] - fZref[0]) / GetPadLength();
624 //____________________________________________________________________
625 void AliTRDseedV1::GetCovAt(Double_t x, Double_t *cov) const
627 // Computes covariance in the y-z plane at radial point x (in tracking coordinates)
628 // and returns the results in the preallocated array cov[3] as :
635 // For the linear transformation
639 // The error propagation has the general form
641 // C_{Y} = T_{x} C_{X} T_{x}^{T}
643 // We apply this formula 2 times. First to calculate the covariance of the tracklet
644 // at point x we consider:
646 // T_{x} = (1 x); X=(y0 dy/dx); C_{X}=#(){#splitline{Var(y0) Cov(y0, dy/dx)}{Cov(y0, dy/dx) Var(dy/dx)}}
648 // and secondly to take into account the tilt angle
650 // T_{#alpha} = #(){#splitline{cos(#alpha) __ sin(#alpha)}{-sin(#alpha) __ cos(#alpha)}}; X=(y z); C_{X}=#(){#splitline{Var(y) 0}{0 Var(z)}}
653 // using simple trigonometrics one can write for this last case
655 // C_{Y}=#frac{1}{1+tg^{2}#alpha} #(){#splitline{(#sigma_{y}^{2}+tg^{2}#alpha#sigma_{z}^{2}) __ tg#alpha(#sigma_{z}^{2}-#sigma_{y}^{2})}{tg#alpha(#sigma_{z}^{2}-#sigma_{y}^{2}) __ (#sigma_{z}^{2}+tg^{2}#alpha#sigma_{y}^{2})}}
657 // which can be aproximated for small alphas (2 deg) with
659 // C_{Y}=#(){#splitline{#sigma_{y}^{2} __ (#sigma_{z}^{2}-#sigma_{y}^{2})tg#alpha}{((#sigma_{z}^{2}-#sigma_{y}^{2})tg#alpha __ #sigma_{z}^{2}}}
662 // before applying the tilt rotation we also apply systematic uncertainties to the tracklet
663 // position which can be tunned from outside via the AliTRDrecoParam::SetSysCovMatrix(). They might
664 // account for extra misalignment/miscalibration uncertainties.
667 // Alex Bercuci <A.Bercuci@gsi.de>
668 // Date : Jan 8th 2009
673 Double_t sy2 = fCov[0] +2.*xr*fCov[1] + xr*xr*fCov[2];
675 //GetPadLength()*GetPadLength()/12.;
677 // insert systematic uncertainties
679 Double_t sys[15]; memset(sys, 0, 15*sizeof(Double_t));
680 fkReconstructor->GetRecoParam()->GetSysCovMatrix(sys);
684 // rotate covariance matrix
685 Double_t t2 = GetTilt()*GetTilt();
686 Double_t correction = 1./(1. + t2);
687 cov[0] = (sy2+t2*sz2)*correction;
688 cov[1] = GetTilt()*(sz2 - sy2)*correction;
689 cov[2] = (t2*sy2+sz2)*correction;
691 //printf("C(%6.1f %+6.3f %6.1f) [%s]\n", 1.e4*TMath::Sqrt(cov[0]), cov[1], 1.e4*TMath::Sqrt(cov[2]), IsRowCross()?" RC ":"-");
694 //____________________________________________________________
695 Double_t AliTRDseedV1::GetCovSqrt(const Double_t * const c, Double_t *d)
697 // Helper function to calculate the square root of the covariance matrix.
698 // The input matrix is stored in the vector c and the result in the vector d.
699 // Both arrays have to be initialized by the user with at least 3 elements. Return negative in case of failure.
701 // For calculating the square root of the symmetric matrix c
702 // the following relation is used:
704 // C^{1/2} = VD^{1/2}V^{-1}
706 // with V being the matrix with the n eigenvectors as columns.
707 // In case C is symmetric the followings are true:
708 // - matrix D is diagonal with the diagonal given by the eigenvalues of C
711 // Author A.Bercuci <A.Bercuci@gsi.de>
714 Double_t l[2], // eigenvalues
715 v[3]; // eigenvectors
716 // the secular equation and its solution :
717 // (c[0]-L)(c[2]-L)-c[1]^2 = 0
718 // L^2 - L*Tr(c)+DET(c) = 0
719 // L12 = [Tr(c) +- sqrt(Tr(c)^2-4*DET(c))]/2
720 Double_t tr = c[0]+c[2], // trace
721 det = c[0]*c[2]-c[1]*c[1]; // determinant
722 if(TMath::Abs(det)<1.e-20) return -1.;
723 Double_t dd = TMath::Sqrt(tr*tr - 4*det);
726 if(l[0]<0. || l[1]<0.) return -1.;
731 Double_t tmp = (l[0]-c[0])/c[1];
732 v[0] = TMath::Sqrt(1./(tmp*tmp+1));
734 v[2] = v[1]*c[1]/(l[1]-c[2]);
736 l[0] = TMath::Sqrt(l[0]); l[1] = TMath::Sqrt(l[1]);
737 d[0] = v[0]*v[0]*l[0]+v[1]*v[1]*l[1];
738 d[1] = v[0]*v[1]*l[0]+v[1]*v[2]*l[1];
739 d[2] = v[1]*v[1]*l[0]+v[2]*v[2]*l[1];
744 //____________________________________________________________
745 Double_t AliTRDseedV1::GetCovInv(const Double_t * const c, Double_t *d)
747 // Helper function to calculate the inverse of the covariance matrix.
748 // The input matrix is stored in the vector c and the result in the vector d.
749 // Both arrays have to be initialized by the user with at least 3 elements
750 // The return value is the determinant or 0 in case of singularity.
752 // Author A.Bercuci <A.Bercuci@gsi.de>
755 Double_t det = c[0]*c[2] - c[1]*c[1];
756 if(TMath::Abs(det)<1.e-20) return 0.;
757 Double_t invDet = 1./det;
764 //____________________________________________________________________
765 UShort_t AliTRDseedV1::GetVolumeId() const
768 while(ic<kNclusters && !fClusters[ic]) ic++;
769 return fClusters[ic] ? fClusters[ic]->GetVolumeId() : 0;
772 //____________________________________________________________________
773 TLinearFitter* AliTRDseedV1::GetFitterY()
775 if(!fgFitterY) fgFitterY = new TLinearFitter(1, "pol1");
776 fgFitterY->ClearPoints();
780 //____________________________________________________________________
781 TLinearFitter* AliTRDseedV1::GetFitterZ()
783 if(!fgFitterZ) fgFitterZ = new TLinearFitter(1, "pol1");
784 fgFitterZ->ClearPoints();
788 //____________________________________________________________________
789 void AliTRDseedV1::Calibrate()
791 // Retrieve calibration and position parameters from OCDB.
792 // The following information are used
794 // - column and row position of first attached cluster. If no clusters are attached
795 // to the tracklet a random central chamber position (c=70, r=7) will be used.
797 // The following information is cached in the tracklet
798 // t0 (trigger delay)
801 // omega*tau = tg(a_L)
802 // diffusion coefficients (longitudinal and transversal)
805 // Alex Bercuci <A.Bercuci@gsi.de>
806 // Date : Jan 8th 2009
809 AliCDBManager *cdb = AliCDBManager::Instance();
810 if(cdb->GetRun() < 0){
811 AliError("OCDB manager not properly initialized");
815 AliTRDcalibDB *calib = AliTRDcalibDB::Instance();
816 AliTRDCalROC *vdROC = calib->GetVdriftROC(fDet),
817 *t0ROC = calib->GetT0ROC(fDet);;
818 const AliTRDCalDet *vdDet = calib->GetVdriftDet();
819 const AliTRDCalDet *t0Det = calib->GetT0Det();
821 Int_t col = 70, row = 7;
822 AliTRDcluster **c = &fClusters[0];
825 while (ic<kNclusters && !(*c)){ic++; c++;}
827 col = (*c)->GetPadCol();
828 row = (*c)->GetPadRow();
832 fT0 = (t0Det->GetValue(fDet) + t0ROC->GetValue(col,row)) / AliTRDCommonParam::Instance()->GetSamplingFrequency();
833 fVD = vdDet->GetValue(fDet) * vdROC->GetValue(col, row);
834 fS2PRF = calib->GetPRFWidth(fDet, col, row); fS2PRF *= fS2PRF;
835 fExB = AliTRDCommonParam::Instance()->GetOmegaTau(fVD);
836 AliTRDCommonParam::Instance()->GetDiffCoeff(fDiffL,
838 SetBit(kCalib, kTRUE);
841 //____________________________________________________________________
842 void AliTRDseedV1::SetOwner()
844 //AliInfo(Form("own [%s] fOwner[%s]", own?"YES":"NO", fOwner?"YES":"NO"));
846 if(TestBit(kOwner)) return;
847 for(int ic=0; ic<kNclusters; ic++){
848 if(!fClusters[ic]) continue;
849 fClusters[ic] = new AliTRDcluster(*fClusters[ic]);
854 //____________________________________________________________
855 void AliTRDseedV1::SetPadPlane(AliTRDpadPlane *p)
857 // Shortcut method to initialize pad geometry.
859 SetTilt(TMath::Tan(TMath::DegToRad()*p->GetTiltingAngle()));
860 SetPadLength(p->GetLengthIPad());
861 SetPadWidth(p->GetWidthIPad());
865 //____________________________________________________________________
866 Bool_t AliTRDseedV1::AttachClusters(AliTRDtrackingChamber *const chamber, Bool_t tilt)
869 // Projective algorithm to attach clusters to seeding tracklets. The following steps are performed :
870 // 1. Collapse x coordinate for the full detector plane
871 // 2. truncated mean on y (r-phi) direction
873 // 4. truncated mean on z direction
877 // - chamber : pointer to tracking chamber container used to search the tracklet
878 // - tilt : switch for tilt correction during road building [default true]
880 // - true : if tracklet found successfully. Failure can happend because of the following:
882 // Detailed description
884 // We start up by defining the track direction in the xy plane and roads. The roads are calculated based
885 // on tracking information (variance in the r-phi direction) and estimated variance of the standard
886 // clusters (see AliTRDcluster::SetSigmaY2()) corrected for tilt (see GetCovAt()). From this the road is
888 // r_{y} = 3*#sqrt{12*(#sigma^{2}_{Trk}(y) + #frac{#sigma^{2}_{cl}(y) + tg^{2}(#alpha_{L})#sigma^{2}_{cl}(z)}{1+tg^{2}(#alpha_{L})})}
889 // r_{z} = 1.5*L_{pad}
892 // Author : Alexandru Bercuci <A.Bercuci@gsi.de>
895 if(!fkReconstructor->GetRecoParam() ){
896 AliError("Seed can not be used without a valid RecoParam.");
899 // Initialize reco params for this tracklet
900 // 1. first time bin in the drift region
902 Int_t kClmin = Int_t(fkReconstructor->GetRecoParam() ->GetFindableClusters()*AliTRDtrackerV1::GetNTimeBins());
904 Double_t sysCov[5]; fkReconstructor->GetRecoParam()->GetSysCovMatrix(sysCov);
905 Double_t s2yTrk= fRefCov[0],
907 s2zCl = GetPadLength()*GetPadLength()/12.,
908 syRef = TMath::Sqrt(s2yTrk),
909 t2 = GetTilt()*GetTilt();
911 Double_t kroady = 1., //fkReconstructor->GetRecoParam() ->GetRoad1y();
912 kroadz = GetPadLength() * fkReconstructor->GetRecoParam()->GetRoadzMultiplicator() + 1.;
913 // define probing cluster (the perfect cluster) and default calibration
914 Short_t sig[] = {0, 0, 10, 30, 10, 0,0};
915 AliTRDcluster cp(fDet, 6, 75, 0, sig, 0);
916 if(fkReconstructor->IsHLT())cp.SetRPhiMethod(AliTRDcluster::kCOG);
920 AliDebug(4, Form("syKalman[%f] rY[%f] rZ[%f]", syRef, kroady, kroadz));
923 const Int_t kNrows = 16;
924 const Int_t kNcls = 3*kNclusters; // buffer size
925 AliTRDcluster *clst[kNrows][kNcls];
926 Bool_t blst[kNrows][kNcls];
927 Double_t cond[4], dx, dy, yt, zt, yres[kNrows][kNcls];
928 Int_t idxs[kNrows][kNcls], ncl[kNrows], ncls = 0;
929 memset(ncl, 0, kNrows*sizeof(Int_t));
930 memset(yres, 0, kNrows*kNcls*sizeof(Double_t));
931 memset(blst, 0, kNrows*kNcls*sizeof(Bool_t)); //this is 8 times faster to memset than "memset(clst, 0, kNrows*kNcls*sizeof(AliTRDcluster*))"
933 // Do cluster projection
934 AliTRDcluster *c = NULL;
935 AliTRDchamberTimeBin *layer = NULL;
936 Bool_t kBUFFER = kFALSE;
937 for (Int_t it = 0; it < kNtb; it++) {
938 if(!(layer = chamber->GetTB(it))) continue;
939 if(!Int_t(*layer)) continue;
940 // get track projection at layers position
941 dx = fX0 - layer->GetX();
942 yt = fYref[0] - fYref[1] * dx;
943 zt = fZref[0] - fZref[1] * dx;
944 // get standard cluster error corrected for tilt
945 cp.SetLocalTimeBin(it);
946 cp.SetSigmaY2(0.02, fDiffT, fExB, dx, -1./*zt*/, fYref[1]);
947 s2yCl = (cp.GetSigmaY2() + sysCov[0] + t2*s2zCl)/(1.+t2);
948 // get estimated road
949 kroady = 3.*TMath::Sqrt(12.*(s2yTrk + s2yCl));
951 AliDebug(5, Form(" %2d x[%f] yt[%f] zt[%f]", it, dx, yt, zt));
953 AliDebug(5, Form(" syTrk[um]=%6.2f syCl[um]=%6.2f syClTlt[um]=%6.2f Ry[mm]=%f", 1.e4*TMath::Sqrt(s2yTrk), 1.e4*TMath::Sqrt(cp.GetSigmaY2()), 1.e4*TMath::Sqrt(s2yCl), 1.e1*kroady));
956 cond[0] = yt; cond[2] = kroady;
957 cond[1] = zt; cond[3] = kroadz;
959 layer->GetClusters(cond, idx, n, 6);
960 for(Int_t ic = n; ic--;){
961 c = (*layer)[idx[ic]];
963 dy += tilt ? GetTilt() * (c->GetZ() - zt) : 0.;
964 // select clusters on a 3 sigmaKalman level
965 /* if(tilt && TMath::Abs(dy) > 3.*syRef){
966 printf("too large !!!\n");
969 Int_t r = c->GetPadRow();
970 AliDebug(5, Form(" -> dy[%f] yc[%f] r[%d]", TMath::Abs(dy), c->GetY(), r));
972 blst[r][ncl[r]] = kTRUE;
973 idxs[r][ncl[r]] = idx[ic];
974 yres[r][ncl[r]] = dy;
977 if(ncl[r] >= kNcls) {
978 AliWarning(Form("Cluster candidates reached buffer limit %d. Some may be lost.", kNcls));
985 AliDebug(4, Form("Found %d clusters. Processing ...", ncls));
987 AliDebug(2, Form("CLUSTERS FOUND %d LESS THAN THRESHOLD %d.", ncls, kClmin));
988 SetErrorMsg(kAttachClFound);
992 // analyze each row individualy
993 Double_t mean, syDis;
994 Int_t nrow[] = {0, 0, 0}, nr = 0, lr=-1;
995 for(Int_t ir=kNrows; ir--;){
996 if(!(ncl[ir])) continue;
997 if(lr>0 && lr-ir != 1){
998 AliDebug(2, "Gap in rows attached");
1000 AliDebug(5, Form(" r[%d] n[%d]", ir, ncl[ir]));
1001 // Evaluate truncated mean on the y direction
1002 if(ncl[ir] > 3) AliMathBase::EvaluateUni(ncl[ir], yres[ir], mean, syDis, Int_t(ncl[ir]*.8));
1004 mean = 0.; syDis = 0.;
1008 if(fkReconstructor->GetRecoParam()->GetStreamLevel(AliTRDrecoParam::kTracker) > 3 && fkReconstructor->IsDebugStreaming()){
1009 TTreeSRedirector &cstreamer = *fkReconstructor->GetDebugStream(AliTRDrecoParam::kTracker);
1010 TVectorD vdy(ncl[ir], yres[ir]);
1012 if(IsKink()) SETBIT(stat, 1);
1013 if(IsStandAlone()) SETBIT(stat, 2);
1014 cstreamer << "AttachClusters"
1025 // TODO check mean and sigma agains cluster resolution !!
1026 AliDebug(4, Form(" m[%f (%5.3fs)] s[%f]", mean, TMath::Abs(mean/syDis), syDis));
1027 // select clusters on a 3 sigmaDistr level
1028 Bool_t kFOUND = kFALSE;
1029 for(Int_t ic = ncl[ir]; ic--;){
1030 if(yres[ir][ic] - mean > 3. * syDis){
1031 blst[ir][ic] = kFALSE; continue;
1033 nrow[nr]++; kFOUND = kTRUE;
1037 lr = ir; if(nr>=3) break;
1039 AliDebug(4, Form(" nr[%d = %d + %d + %d]", nr, nrow[0], nrow[1], nrow[2]));
1041 // classify cluster rows
1048 SetBit(kRowCross, kTRUE); // mark pad row crossing
1049 if(nrow[0] > nrow[1]){ row = lr+1; lr = -1;}
1058 SetBit(kRowCross, kTRUE); // mark pad row crossing
1061 AliDebug(4, Form(" Ncl[rowMax = %d] = %d", row, nrow[0]));
1063 AliDebug(2, Form("WRONG ROW %d.", row));
1064 SetErrorMsg(kAttachRow);
1067 // Select and store clusters
1068 // We should consider here :
1069 // 1. How far is the chamber boundary
1070 // 2. How big is the mean
1072 for (Int_t ir = 0; ir < nr; ir++) {
1073 Int_t jr = row + ir*lr;
1074 AliDebug(4, Form(" Ncl[%d] @ R[%d] attaching ...", ncl[jr], jr));
1075 for (Int_t ic = 0; ic < ncl[jr]; ic++) {
1076 if(!blst[jr][ic])continue;
1078 Int_t it = c->GetPadTime();
1079 Int_t idx = it+kNtb*ir;
1081 AliDebug(2, Form("Cluster position already allocated tb[%2d] r[%d]. Skip !", it, jr));
1082 SetErrorMsg(kAttachMultipleCl);
1086 // TODO proper indexing of clusters !!
1087 fIndexes[idx] = chamber->GetTB(it)->GetGlobalIndex(idxs[jr][ic]);
1094 // number of minimum numbers of clusters expected for the tracklet
1095 if (GetN() < kClmin){
1096 AliDebug(2, Form("NOT ENOUGH CLUSTERS ATTACHED TO THE TRACKLET %d [%d] FROM FOUND [%d].", GetN(), kClmin, n));
1097 SetErrorMsg(kAttachClAttach);
1101 // Load calibration parameters for this tracklet
1104 // calculate dx for time bins in the drift region (calibration aware)
1105 Float_t x[2] = {0.,0.}; Int_t tb[2]={0,0};
1106 for (Int_t it = t0, irp=0; irp<2 && it < AliTRDtrackerV1::GetNTimeBins(); it++) {
1107 if(!fClusters[it]) continue;
1108 x[irp] = fClusters[it]->GetX();
1109 tb[irp] = fClusters[it]->GetLocalTimeBin();
1112 Int_t dtb = tb[1] - tb[0];
1113 fdX = dtb ? (x[0] - x[1]) / dtb : 0.15;
1117 //____________________________________________________________
1118 void AliTRDseedV1::Bootstrap(const AliTRDReconstructor *rec)
1120 // Fill in all derived information. It has to be called after recovery from file or HLT.
1121 // The primitive data are
1122 // - list of clusters
1123 // - detector (as the detector will be removed from clusters)
1124 // - position of anode wire (fX0) - temporary
1125 // - track reference position and direction
1126 // - momentum of the track
1127 // - time bin length [cm]
1129 // A.Bercuci <A.Bercuci@gsi.de> Oct 30th 2008
1131 fkReconstructor = rec;
1133 AliTRDpadPlane *pp = g.GetPadPlane(fDet);
1134 fPad[0] = pp->GetLengthIPad();
1135 fPad[1] = pp->GetWidthIPad();
1136 fPad[3] = TMath::Tan(TMath::DegToRad()*pp->GetTiltingAngle());
1137 //fSnp = fYref[1]/TMath::Sqrt(1+fYref[1]*fYref[1]);
1139 Int_t n = 0, nshare = 0, nused = 0;
1140 AliTRDcluster **cit = &fClusters[0];
1141 for(Int_t ic = kNclusters; ic--; cit++){
1144 if((*cit)->IsShared()) nshare++;
1145 if((*cit)->IsUsed()) nused++;
1147 SetN(n); SetNUsed(nused); SetNShared(nshare);
1154 //____________________________________________________________________
1155 Bool_t AliTRDseedV1::Fit(Bool_t tilt, Bool_t zcorr)
1158 // Linear fit of the clusters attached to the tracklet
1161 // - tilt : switch for tilt pad correction of cluster y position based on
1162 // the z, dzdx info from outside [default false].
1163 // - zcorr : switch for using z information to correct for anisochronity
1164 // and a finner error parameterization estimation [default false]
1166 // True if successful
1168 // Detailed description
1170 // Fit in the xy plane
1172 // The fit is performed to estimate the y position of the tracklet and the track
1173 // angle in the bending plane. The clusters are represented in the chamber coordinate
1174 // system (with respect to the anode wire - see AliTRDtrackerV1::FollowBackProlongation()
1175 // on how this is set). The x and y position of the cluster and also their variances
1176 // are known from clusterizer level (see AliTRDcluster::GetXloc(), AliTRDcluster::GetYloc(),
1177 // AliTRDcluster::GetSX() and AliTRDcluster::GetSY()).
1178 // If gaussian approximation is used to calculate y coordinate of the cluster the position
1179 // is recalculated taking into account the track angle. The general formula to calculate the
1180 // error of cluster position in the gaussian approximation taking into account diffusion and track
1181 // inclination is given for TRD by:
1183 // #sigma^{2}_{y} = #sigma^{2}_{PRF} + #frac{x#delta_{t}^{2}}{(1+tg(#alpha_{L}))^{2}} + #frac{x^{2}tg^{2}(#phi-#alpha_{L})tg^{2}(#alpha_{L})}{12}
1186 // Since errors are calculated only in the y directions, radial errors (x direction) are mapped to y
1187 // by projection i.e.
1189 // #sigma_{x|y} = tg(#phi) #sigma_{x}
1191 // and also by the lorentz angle correction
1193 // Fit in the xz plane
1195 // The "fit" is performed to estimate the radial position (x direction) where pad row cross happens.
1196 // If no pad row crossing the z position is taken from geometry and radial position is taken from the xy
1199 // There are two methods to estimate the radial position of the pad row cross:
1200 // 1. leading cluster radial position : Here the lower part of the tracklet is considered and the last
1201 // cluster registered (at radial x0) on this segment is chosen to mark the pad row crossing. The error
1202 // of the z estimate is given by :
1204 // #sigma_{z} = tg(#theta) #Delta x_{x_{0}}/12
1206 // The systematic errors for this estimation are generated by the following sources:
1207 // - no charge sharing between pad rows is considered (sharp cross)
1208 // - missing cluster at row cross (noise peak-up, under-threshold signal etc.).
1210 // 2. charge fit over the crossing point : Here the full energy deposit along the tracklet is considered
1211 // to estimate the position of the crossing by a fit in the qx plane. The errors in the q directions are
1212 // parameterized as s_q = q^2. The systematic errors for this estimation are generated by the following sources:
1213 // - no general model for the qx dependence
1214 // - physical fluctuations of the charge deposit
1215 // - gain calibration dependence
1217 // Estimation of the radial position of the tracklet
1219 // For pad row cross the radial position is taken from the xz fit (see above). Otherwise it is taken as the
1220 // interpolation point of the tracklet i.e. the point where the error in y of the fit is minimum. The error
1221 // in the y direction of the tracklet is (see AliTRDseedV1::GetCovAt()):
1223 // #sigma_{y} = #sigma^{2}_{y_{0}} + 2xcov(y_{0}, dy/dx) + #sigma^{2}_{dy/dx}
1225 // and thus the radial position is:
1227 // x = - cov(y_{0}, dy/dx)/#sigma^{2}_{dy/dx}
1230 // Estimation of tracklet position error
1232 // The error in y direction is the error of the linear fit at the radial position of the tracklet while in the z
1233 // direction is given by the cluster error or pad row cross error. In case of no pad row cross this is given by:
1235 // #sigma_{y} = #sigma^{2}_{y_{0}} - 2cov^{2}(y_{0}, dy/dx)/#sigma^{2}_{dy/dx} + #sigma^{2}_{dy/dx}
1236 // #sigma_{z} = Pad_{length}/12
1238 // For pad row cross the full error is calculated at the radial position of the crossing (see above) and the error
1239 // in z by the width of the crossing region - being a matter of parameterization.
1241 // #sigma_{z} = tg(#theta) #Delta x_{x_{0}}/12
1243 // In case of no tilt correction (default in the barrel tracking) the tilt is taken into account by the rotation of
1244 // the covariance matrix. See AliTRDseedV1::GetCovAt() for details.
1247 // A.Bercuci <A.Bercuci@gsi.de>
1249 if(!IsCalibrated()) Calibrate();
1251 const Int_t kClmin = 8;
1253 // get track direction
1254 Double_t y0 = fYref[0];
1255 Double_t dydx = fYref[1];
1256 Double_t z0 = fZref[0];
1257 Double_t dzdx = fZref[1];
1260 AliTRDtrackerV1::AliTRDLeastSquare fitterY;
1261 AliTRDtrackerV1::AliTRDLeastSquare fitterZ;
1263 // book cluster information
1264 Double_t qc[kNclusters], xc[kNclusters], yc[kNclusters], zc[kNclusters], sy[kNclusters];
1267 AliTRDcluster *c=NULL, **jc = &fClusters[0];
1268 for (Int_t ic=0; ic<kNtb; ic++, ++jc) {
1273 if(!(c = (*jc))) continue;
1274 if(!c->IsInChamber()) continue;
1277 if(c->GetNPads()>4) w = .5;
1278 if(c->GetNPads()>5) w = .2;
1281 qc[n] = TMath::Abs(c->GetQ());
1282 // pad row of leading
1284 // Radial cluster position
1285 //Int_t jc = TMath::Max(fN-3, 0);
1286 //xc[fN] = c->GetXloc(fT0, fVD, &qc[jc], &xc[jc]/*, z0 - c->GetX()*dzdx*/);
1287 xc[n] = fX0 - c->GetX();
1289 // extrapolated track to cluster position
1290 yt = y0 - xc[n]*dydx;
1291 zt = z0 - xc[n]*dzdx;
1293 // Recalculate cluster error based on tracking information
1294 c->SetSigmaY2(fS2PRF, fDiffT, fExB, xc[n], zcorr?zt:-1., dydx);
1295 sy[n] = TMath::Sqrt(c->GetSigmaY2());
1297 yc[n] = fkReconstructor->GetRecoParam()->UseGAUS() ?
1298 c->GetYloc(y0, sy[n], GetPadWidth()): c->GetY();
1300 //optional tilt correction
1301 if(tilt) yc[n] -= (GetTilt()*(zc[n] - zt));
1303 fitterY.AddPoint(&xc[n], yc[n], TMath::Sqrt(sy[n]));
1304 if(IsRowCross())fitterZ.AddPoint(&xc[n], qc[n], 1.);
1309 if (n < kClmin) return kFALSE;
1313 fYfit[0] = fitterY.GetFunctionParameter(0);
1314 fYfit[1] = -fitterY.GetFunctionParameter(1);
1317 fitterY.GetCovarianceMatrix(p);
1318 fCov[0] = p[0]; // variance of y0
1319 fCov[1] = p[2]; // covariance of y0, dydx
1320 fCov[2] = p[1]; // variance of dydx
1321 // the ref radial position is set at the minimum of
1322 // the y variance of the tracklet
1323 fX = -fCov[1]/fCov[2];
1327 /* // THE LEADING CLUSTER METHOD
1329 Int_t ic=n=kNclusters-1; jc = &fClusters[ic];
1330 AliTRDcluster *c0 =0x0, **kc = &fClusters[kNtb-1];
1331 for(; ic>kNtb; ic--, --jc, --kc){
1332 if((c0 = (*kc)) && c0->IsInChamber() && (xMin>c0->GetX())) xMin = c0->GetX();
1333 if(!(c = (*jc))) continue;
1334 if(!c->IsInChamber()) continue;
1335 zc[kNclusters-1] = c->GetZ();
1336 fX = fX0 - c->GetX();
1338 fZfit[0] = .5*(zc[0]+zc[kNclusters-1]); fZfit[1] = 0.;
1339 // Error parameterization
1340 fS2Z = fdX*fZref[1];
1341 fS2Z *= fS2Z; fS2Z *= 0.2887; // 1/sqrt(12)*/
1343 // THE FIT X-Q PLANE METHOD
1344 Int_t ic=n=kNclusters-1; jc = &fClusters[ic];
1345 for(; ic>kNtb; ic--, --jc){
1346 if(!(c = (*jc))) continue;
1347 if(!c->IsInChamber()) continue;
1348 qc[n] = TMath::Abs(c->GetQ());
1349 xc[n] = fX0 - c->GetX();
1351 fitterZ.AddPoint(&xc[n], -qc[n], 1.);
1356 if(fitterZ.GetFunctionParameter(1)!=0.){
1357 fX = -fitterZ.GetFunctionParameter(0)/fitterZ.GetFunctionParameter(1);
1359 Float_t dl = .5*AliTRDgeometry::CamHght()+AliTRDgeometry::CdrHght();
1361 fX-=.055; // TODO to be understood
1364 fZfit[0] = .5*(zc[0]+zc[kNclusters-1]); fZfit[1] = 0.;
1365 // temporary external error parameterization
1366 fS2Z = 0.05+0.4*TMath::Abs(fZref[1]); fS2Z *= fS2Z;
1367 // TODO correct formula
1368 //fS2Z = sigma_x*TMath::Abs(fZref[1]);
1370 fZfit[0] = zc[0]; fZfit[1] = 0.;
1371 fS2Z = GetPadLength()*GetPadLength()/12.;
1373 fS2Y = fCov[0] +2.*fX*fCov[1] + fX*fX*fCov[2];
1379 //_____________________________________________________________________________
1380 void AliTRDseedV1::FitMI()
1384 // Marian Ivanov's version
1386 // linear fit on the y direction with respect to the reference direction.
1387 // The residuals for each x (x = xc - x0) are deduced from:
1389 // the tilting correction is written :
1390 // y = yc + h*(zc-zt) (2)
1391 // yt = y0+dy/dx*x (3)
1392 // zt = z0+dz/dx*x (4)
1393 // from (1),(2),(3) and (4)
1394 // dy = yc - y0 - (dy/dx + h*dz/dx)*x + h*(zc-z0)
1395 // the last term introduces the correction on y direction due to tilting pads. There are 2 ways to account for this:
1396 // 1. use tilting correction for calculating the y
1397 // 2. neglect tilting correction here and account for it in the error parametrization of the tracklet.
1398 const Float_t kRatio = 0.8;
1399 const Int_t kClmin = 5;
1400 const Float_t kmaxtan = 2;
1402 if (TMath::Abs(fYref[1]) > kmaxtan){
1403 //printf("Exit: Abs(fYref[1]) = %3.3f, kmaxtan = %3.3f\n", TMath::Abs(fYref[1]), kmaxtan);
1404 return; // Track inclined too much
1407 Float_t sigmaexp = 0.05 + TMath::Abs(fYref[1] * 0.25); // Expected r.m.s in y direction
1408 Float_t ycrosscor = GetPadLength() * GetTilt() * 0.5; // Y correction for crossing
1419 // Buffering: Leave it constant fot Performance issues
1420 Int_t zints[kNtb]; // Histograming of the z coordinate
1421 // Get 1 and second max probable coodinates in z
1422 Int_t zouts[2*kNtb];
1423 Float_t allowedz[kNtb]; // Allowed z for given time bin
1424 Float_t yres[kNtb]; // Residuals from reference
1425 //Float_t anglecor = GetTilt() * fZref[1]; // Correction to the angle
1427 Float_t pos[3*kNtb]; memset(pos, 0, 3*kNtb*sizeof(Float_t));
1428 Float_t *fX = &pos[0], *fY = &pos[kNtb], *fZ = &pos[2*kNtb];
1430 Int_t fN = 0; AliTRDcluster *c = 0x0;
1432 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins(); i++) {
1434 if (!(c = fClusters[i])) continue;
1435 if(!c->IsInChamber()) continue;
1437 //yres[i] = fY[i] - fYref[0] - (fYref[1] + anglecor) * fX[i] + GetTilt()*(fZ[i] - fZref[0]);
1438 fX[i] = fX0 - c->GetX();
1441 yres[i] = fY[i] - GetTilt()*(fZ[i] - (fZref[0] - fX[i]*fZref[1]));
1442 zints[fN] = Int_t(fZ[i]);
1447 //printf("Exit fN < kClmin: fN = %d\n", fN);
1450 Int_t nz = AliTRDtrackerV1::Freq(fN, zints, zouts, kFALSE);
1451 Float_t fZProb = zouts[0];
1452 if (nz <= 1) zouts[3] = 0;
1453 if (zouts[1] + zouts[3] < kClmin) {
1454 //printf("Exit zouts[1] = %d, zouts[3] = %d\n",zouts[1],zouts[3]);
1458 // Z distance bigger than pad - length
1459 if (TMath::Abs(zouts[0]-zouts[2]) > 12.0) zouts[3] = 0;
1461 Int_t breaktime = -1;
1462 Bool_t mbefore = kFALSE;
1463 Int_t cumul[kNtb][2];
1464 Int_t counts[2] = { 0, 0 };
1466 if (zouts[3] >= 3) {
1469 // Find the break time allowing one chage on pad-rows
1470 // with maximal number of accepted clusters
1473 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins(); i++) {
1474 cumul[i][0] = counts[0];
1475 cumul[i][1] = counts[1];
1476 if (TMath::Abs(fZ[i]-zouts[0]) < 2) counts[0]++;
1477 if (TMath::Abs(fZ[i]-zouts[2]) < 2) counts[1]++;
1480 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins(); i++) {
1481 Int_t after = cumul[AliTRDtrackerV1::GetNTimeBins()][0] - cumul[i][0];
1482 Int_t before = cumul[i][1];
1483 if (after + before > maxcount) {
1484 maxcount = after + before;
1488 after = cumul[AliTRDtrackerV1::GetNTimeBins()-1][1] - cumul[i][1];
1489 before = cumul[i][0];
1490 if (after + before > maxcount) {
1491 maxcount = after + before;
1499 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1500 if (i > breaktime) allowedz[i] = mbefore ? zouts[2] : zouts[0];
1501 if (i <= breaktime) allowedz[i] = (!mbefore) ? zouts[2] : zouts[0];
1504 if (((allowedz[0] > allowedz[AliTRDtrackerV1::GetNTimeBins()]) && (fZref[1] < 0)) ||
1505 ((allowedz[0] < allowedz[AliTRDtrackerV1::GetNTimeBins()]) && (fZref[1] > 0))) {
1507 // Tracklet z-direction not in correspondance with track z direction
1510 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1511 allowedz[i] = zouts[0]; // Only longest taken
1517 // Cross pad -row tracklet - take the step change into account
1519 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1520 if (!fClusters[i]) continue;
1521 if(!fClusters[i]->IsInChamber()) continue;
1522 if (TMath::Abs(fZ[i] - allowedz[i]) > 2) continue;
1524 //yres[i] = fY[i] - fYref[0] - (fYref[1] + anglecor) * fX[i] + GetTilt()*(fZ[i] - fZref[0]);
1525 yres[i] = fY[i] - GetTilt()*(fZ[i] - (fZref[0] - fX[i]*fZref[1]));
1526 // if (TMath::Abs(fZ[i] - fZProb) > 2) {
1527 // if (fZ[i] > fZProb) yres[i] += GetTilt() * GetPadLength();
1528 // if (fZ[i] < fZProb) yres[i] -= GetTilt() * GetPadLength();
1533 Double_t yres2[kNtb];
1536 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1537 if (!fClusters[i]) continue;
1538 if(!fClusters[i]->IsInChamber()) continue;
1539 if (TMath::Abs(fZ[i] - allowedz[i]) > 2) continue;
1540 yres2[fN2] = yres[i];
1544 //printf("Exit fN2 < kClmin: fN2 = %d\n", fN2);
1548 AliMathBase::EvaluateUni(fN2,yres2,mean,sigma, Int_t(fN2*kRatio-2.));
1549 if (sigma < sigmaexp * 0.8) {
1552 //Float_t fSigmaY = sigma;
1567 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1568 if (!fClusters[i]) continue;
1569 if (!fClusters[i]->IsInChamber()) continue;
1570 if (TMath::Abs(fZ[i] - allowedz[i]) > 2){fClusters[i] = 0x0; continue;}
1571 if (TMath::Abs(yres[i] - mean) > 4.0 * sigma){fClusters[i] = 0x0; continue;}
1574 fMPads += fClusters[i]->GetNPads();
1575 Float_t weight = 1.0;
1576 if (fClusters[i]->GetNPads() > 4) weight = 0.5;
1577 if (fClusters[i]->GetNPads() > 5) weight = 0.2;
1581 //printf("x = %7.3f dy = %7.3f fit %7.3f\n", x, yres[i], fY[i]-yres[i]);
1584 sumwx += x * weight;
1585 sumwx2 += x*x * weight;
1586 sumwy += weight * yres[i];
1587 sumwxy += weight * (yres[i]) * x;
1588 sumwz += weight * fZ[i];
1589 sumwxz += weight * fZ[i] * x;
1594 //printf("Exit fN2 < kClmin(2): fN2 = %d\n",fN2);
1598 fMeanz = sumwz / sumw;
1599 Float_t correction = 0;
1601 // Tracklet on boundary
1602 if (fMeanz < fZProb) correction = ycrosscor;
1603 if (fMeanz > fZProb) correction = -ycrosscor;
1606 Double_t det = sumw * sumwx2 - sumwx * sumwx;
1607 fYfit[0] = (sumwx2 * sumwy - sumwx * sumwxy) / det;
1608 fYfit[1] = (sumw * sumwxy - sumwx * sumwy) / det;
1611 for (Int_t i = 0; i < AliTRDtrackerV1::GetNTimeBins()+1; i++) {
1612 if (!TESTBIT(fUsable,i)) continue;
1613 Float_t delta = yres[i] - fYfit[0] - fYfit[1] * fX[i];
1614 fS2Y += delta*delta;
1616 fS2Y = TMath::Sqrt(fS2Y / Float_t(fN2-2));
1617 // TEMPORARY UNTIL covariance properly calculated
1618 fS2Y = TMath::Max(fS2Y, Float_t(.1));
1620 fZfit[0] = (sumwx2 * sumwz - sumwx * sumwxz) / det;
1621 fZfit[1] = (sumw * sumwxz - sumwx * sumwz) / det;
1622 // fYfitR[0] += fYref[0] + correction;
1623 // fYfitR[1] += fYref[1];
1624 // fYfit[0] = fYfitR[0];
1625 fYfit[1] = -fYfit[1];
1630 //___________________________________________________________________
1631 void AliTRDseedV1::Print(Option_t *o) const
1634 // Printing the seedstatus
1637 AliInfo(Form("Det[%3d] X0[%7.2f] Pad{L[%5.2f] W[%5.2f] Tilt[%+6.2f]}", fDet, fX0, GetPadLength(), GetPadWidth(), GetTilt()));
1638 AliInfo(Form("N[%2d] Nused[%2d] Nshared[%2d] [%d]", GetN(), GetNUsed(), GetNShared(), fN));
1639 AliInfo(Form("FLAGS : RC[%c] Kink[%c] SA[%c]", IsRowCross()?'y':'n', IsKink()?'y':'n', IsStandAlone()?'y':'n'));
1641 Double_t cov[3], x=GetX();
1643 AliInfo(" | x[cm] | y[cm] | z[cm] | dydx | dzdx |");
1644 AliInfo(Form("Fit | %7.2f | %7.2f+-%7.2f | %7.2f+-%7.2f| %5.2f | ----- |", x, GetY(), TMath::Sqrt(cov[0]), GetZ(), TMath::Sqrt(cov[2]), fYfit[1]));
1645 AliInfo(Form("Ref | %7.2f | %7.2f+-%7.2f | %7.2f+-%7.2f| %5.2f | %5.2f |", x, fYref[0]-fX*fYref[1], TMath::Sqrt(fRefCov[0]), fZref[0]-fX*fYref[1], TMath::Sqrt(fRefCov[2]), fYref[1], fZref[1]))
1646 AliInfo(Form("P / Pt [GeV/c] = %f / %f", GetMomentum(), fPt));
1647 AliInfo(Form("dEdx [a.u.] = %f / %f / %f / %f / %f/ %f / %f / %f", fdEdx[0], fdEdx[1], fdEdx[2], fdEdx[3], fdEdx[4], fdEdx[5], fdEdx[6], fdEdx[7]));
1648 AliInfo(Form("PID = %5.3f / %5.3f / %5.3f / %5.3f / %5.3f", fProb[0], fProb[1], fProb[2], fProb[3], fProb[4]));
1650 if(strcmp(o, "a")!=0) return;
1652 AliTRDcluster* const* jc = &fClusters[0];
1653 for(int ic=0; ic<kNclusters; ic++, jc++) {
1654 if(!(*jc)) continue;
1660 //___________________________________________________________________
1661 Bool_t AliTRDseedV1::IsEqual(const TObject *o) const
1663 // Checks if current instance of the class has the same essential members
1666 if(!o) return kFALSE;
1667 const AliTRDseedV1 *inTracklet = dynamic_cast<const AliTRDseedV1*>(o);
1668 if(!inTracklet) return kFALSE;
1670 for (Int_t i = 0; i < 2; i++){
1671 if ( fYref[i] != inTracklet->fYref[i] ) return kFALSE;
1672 if ( fZref[i] != inTracklet->fZref[i] ) return kFALSE;
1675 if ( fS2Y != inTracklet->fS2Y ) return kFALSE;
1676 if ( GetTilt() != inTracklet->GetTilt() ) return kFALSE;
1677 if ( GetPadLength() != inTracklet->GetPadLength() ) return kFALSE;
1679 for (Int_t i = 0; i < kNclusters; i++){
1680 // if ( fX[i] != inTracklet->GetX(i) ) return kFALSE;
1681 // if ( fY[i] != inTracklet->GetY(i) ) return kFALSE;
1682 // if ( fZ[i] != inTracklet->GetZ(i) ) return kFALSE;
1683 if ( fIndexes[i] != inTracklet->fIndexes[i] ) return kFALSE;
1685 // if ( fUsable != inTracklet->fUsable ) return kFALSE;
1687 for (Int_t i=0; i < 2; i++){
1688 if ( fYfit[i] != inTracklet->fYfit[i] ) return kFALSE;
1689 if ( fZfit[i] != inTracklet->fZfit[i] ) return kFALSE;
1690 if ( fLabels[i] != inTracklet->fLabels[i] ) return kFALSE;
1693 /* if ( fMeanz != inTracklet->GetMeanz() ) return kFALSE;
1694 if ( fZProb != inTracklet->GetZProb() ) return kFALSE;*/
1695 if ( fN != inTracklet->fN ) return kFALSE;
1696 //if ( fNUsed != inTracklet->fNUsed ) return kFALSE;
1697 //if ( fFreq != inTracklet->GetFreq() ) return kFALSE;
1698 //if ( fNChange != inTracklet->GetNChange() ) return kFALSE;
1700 if ( fC != inTracklet->fC ) return kFALSE;
1701 //if ( fCC != inTracklet->GetCC() ) return kFALSE;
1702 if ( fChi2 != inTracklet->fChi2 ) return kFALSE;
1703 // if ( fChi2Z != inTracklet->GetChi2Z() ) return kFALSE;
1705 if ( fDet != inTracklet->fDet ) return kFALSE;
1706 if ( fPt != inTracklet->fPt ) return kFALSE;
1707 if ( fdX != inTracklet->fdX ) return kFALSE;
1709 for (Int_t iCluster = 0; iCluster < kNclusters; iCluster++){
1710 AliTRDcluster *curCluster = fClusters[iCluster];
1711 AliTRDcluster *inCluster = inTracklet->fClusters[iCluster];
1712 if (curCluster && inCluster){
1713 if (! curCluster->IsEqual(inCluster) ) {
1714 curCluster->Print();
1719 // if one cluster exists, and corresponding
1720 // in other tracklet doesn't - return kFALSE
1721 if(curCluster || inCluster) return kFALSE;