1 /**************************************************************************
2 * Copyright(c) 1998-2003, 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 **************************************************************************/
16 //-----------------------------------------------------------------
17 // Implementation of the vertexer from tracks
19 // Origin: AliITSVertexerTracks
21 // andrea.dainese@pd.infn.it
23 // massimo.masera@to.infn.it
24 // Moved to STEER and adapted to ESD tracks:
25 // F.Prino, Torino, prino@to.infn.it
26 //-----------------------------------------------------------------
28 //---- Root headers --------
30 #include <TDirectory.h>
34 //---- AliRoot headers -----
35 #include "AliStrLine.h"
36 #include "AliExternalTrackParam.h"
37 #include "AliESDEvent.h"
38 #include "AliESDtrack.h"
39 #include "AliVertexerTracks.h"
41 ClassImp(AliVertexerTracks)
44 //----------------------------------------------------------------------------
45 AliVertexerTracks::AliVertexerTracks():
67 // Default constructor
76 //----------------------------------------------------------------------------
77 AliVertexerTracks::AliVertexerTracks(Double_t fieldkG):
99 // Standard constructor
109 //-----------------------------------------------------------------------------
110 AliVertexerTracks::~AliVertexerTracks()
112 // Default Destructor
113 // The objects pointed by the following pointer are not owned
114 // by this class and are not deleted
116 if(fTrksToSkip) { delete [] fTrksToSkip; fTrksToSkip=NULL; }
117 if(fIdSel) { delete [] fIdSel; fIdSel=NULL; }
119 //----------------------------------------------------------------------------
120 AliESDVertex* AliVertexerTracks::FindPrimaryVertex(const AliESDEvent *esdEvent)
123 // Primary vertex for current ESD event
125 // 1st with 5*fNSigma*sigma cut w.r.t. to initial vertex
126 // + cut on sqrt(d0d0+z0z0) if fConstraint=kFALSE
127 // 2nd with fNSigma*sigma cut w.r.t. to vertex found in 1st iteration)
131 // accept 1-track case only if constraint is available
132 if(!fConstraint && fMinTracks==1) fMinTracks=2;
134 // read tracks from ESD
135 Int_t nTrks = (Int_t)esdEvent->GetNumberOfTracks();
138 return fCurrentVertex;
142 TDirectory * olddir = gDirectory;
143 TFile f("VertexerTracks.root","recreate");
144 TObjArray trkArrayOrig(nTrks);
145 UShort_t *idOrig = new UShort_t[nTrks];
148 for(Int_t i=0; i<nTrks; i++) {
149 AliESDtrack *esdt = esdEvent->GetTrack(i);
150 // check tracks to skip
151 Bool_t skipThis = kFALSE;
152 for(Int_t j=0; j<fNTrksToSkip; j++) {
153 if(esdt->GetID()==fTrksToSkip[j]) {
154 if(fDebug) printf("skipping track: %d\n",i);
158 if(skipThis) continue;
160 if(!(esdt->GetStatus()&AliESDtrack::kITSrefit)) continue;
161 // check number of clusters in ITS
162 if(esdt->GetNcls(0)<fMinITSClusters) continue;
164 Double_t x,p[5],cov[15];
165 esdt->GetExternalParameters(x,p);
166 esdt->GetExternalCovariance(cov);
167 AliExternalTrackParam *t = new AliExternalTrackParam(x,esdt->GetAlpha(),p,cov);
168 trkArrayOrig.AddLast(t);
169 idOrig[nTrksOrig]=(UShort_t)esdt->GetID();
173 FindPrimaryVertex(&trkArrayOrig,idOrig);
175 trkArrayOrig.Delete();
176 delete [] idOrig; idOrig=NULL;
178 gSystem->Unlink("VertexerTracks.root");
181 return fCurrentVertex;
183 //----------------------------------------------------------------------------
184 AliESDVertex* AliVertexerTracks::FindPrimaryVertex(TObjArray *trkArrayOrig,
188 // Primary vertex using the AliExternalTrackParam's in the TObjArray.
189 // idOrig must contain the track IDs from AliESDtrack::GetID()
191 // 1st with 5*fNSigma*sigma cut w.r.t. to initial vertex
192 // + cut on sqrt(d0d0+z0z0) if fConstraint=kFALSE
193 // 2nd with fNSigma*sigma cut w.r.t. to vertex found in 1st iteration)
197 // accept 1-track case only if constraint is available
198 if(!fConstraint && fMinTracks==1) fMinTracks=2;
200 // read tracks from ESD
201 Int_t nTrksOrig = (Int_t)trkArrayOrig->GetEntriesFast();
202 if(fDebug) printf("Initial number of tracks: %d\n",nTrksOrig);
204 if(fDebug) printf("TooFewTracks\n");
206 return fCurrentVertex;
209 // If fConstraint=kFALSE
210 // run VertexFinder(1) to get rough estimate of initVertex (x,y)
212 // fill fTrkArraySel, for VertexFinder()
213 fIdSel = new UShort_t[nTrksOrig];
214 PrepareTracks(*trkArrayOrig,idOrig,0);
215 if(fIdSel) { delete [] fIdSel; fIdSel=NULL; }
216 Double_t cutsave = fDCAcut;
217 fDCAcut = (fITSrefit ? 0.1 : 0.5);
218 VertexFinder(1); // using weights, cutting dca < fDCAcut
220 if(fVert.GetNContributors()>0) {
221 fVert.GetXYZ(fNominalPos);
222 fNominalPos[0] = fVert.GetXv();
223 fNominalPos[1] = fVert.GetYv();
224 fNominalPos[2] = fVert.GetZv();
225 if(fDebug) printf("No mean vertex: VertexFinder gives (%f, %f, %f)\n",fNominalPos[0],fNominalPos[1],fNominalPos[2]);
230 if(fDebug) printf("No mean vertex and VertexFinder failed\n");
237 // propagate tracks to fNominalPos vertex
239 // if(constraint) reject for |d0|>5*fNSigma*sigma w.r.t. fNominal... vertex
240 // else reject for |d0|\oplus|z0| > 5 mm w.r.t. fNominal... vertex
242 // propagate tracks to best between initVertex and fCurrentVertex
243 // preselect tracks (reject for |d0|>fNSigma*sigma w.r.t. best
244 // between initVertex and fCurrentVertex)
245 for(Int_t iter=1; iter<=2; iter++) {
246 if(fOnlyFitter && iter==1) continue;
247 if(fIdSel) { delete [] fIdSel; fIdSel=NULL; }
248 fIdSel = new UShort_t[nTrksOrig];
249 Int_t nTrksSel = PrepareTracks(*trkArrayOrig,idOrig,iter);
250 if(fDebug) printf("N tracks selected in iteration %d: %d\n",iter,nTrksSel);
251 if(nTrksSel < fMinTracks) {
253 return fCurrentVertex;
259 if(fDebug) printf("Just one track\n");
260 OneTrackVertFinder();
263 case 1: StrLinVertexFinderMinDist(1); break;
264 case 2: StrLinVertexFinderMinDist(0); break;
265 case 3: HelixVertexFinder(); break;
266 case 4: VertexFinder(1); break;
267 case 5: VertexFinder(0); break;
268 default: printf("Wrong algorithm\n"); break;
271 if(fDebug) printf(" Vertex finding completed\n");
276 } // end loop on the two iterations
279 // set indices of used tracks
280 UShort_t *indices = 0;
281 if(fCurrentVertex->GetNContributors()>0) {
282 Int_t nIndices = (Int_t)fTrkArraySel.GetEntriesFast();
283 indices = new UShort_t[nIndices];
284 for(Int_t jj=0; jj<nIndices; jj++)
285 indices[jj] = fIdSel[jj];
286 fCurrentVertex->SetIndices(nIndices,indices);
288 delete [] indices; indices=NULL;
292 TString title="VertexerTracksNoConstraint";
294 title="VertexerTracksWithConstraint";
295 if(fOnlyFitter) title.Append("OnlyFitter");
297 fCurrentVertex->SetTitle(title.Data());
301 fCurrentVertex->PrintStatus();
302 fCurrentVertex->PrintIndices();
306 delete [] fIdSel; fIdSel=NULL;
307 fTrkArraySel.Delete();
308 if(fTrksToSkip) { delete [] fTrksToSkip; fTrksToSkip=NULL; }
311 return fCurrentVertex;
313 //------------------------------------------------------------------------
314 Double_t AliVertexerTracks::GetDeterminant3X3(Double_t matr[][3])
317 Double_t det=matr[0][0]*matr[1][1]*matr[2][2]-matr[0][0]*matr[1][2]*matr[2][1]-matr[0][1]*matr[1][0]*matr[2][2]+matr[0][1]*matr[1][2]*matr[2][0]+matr[0][2]*matr[1][0]*matr[2][1]-matr[0][2]*matr[1][1]*matr[2][0];
320 //-------------------------------------------------------------------------
321 void AliVertexerTracks::GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t (*m)[3],Double_t *d)
324 Double_t x12=p0[0]-p1[0];
325 Double_t y12=p0[1]-p1[1];
326 Double_t z12=p0[2]-p1[2];
327 Double_t kk=x12*x12+y12*y12+z12*z12;
328 m[0][0]=2-2/kk*x12*x12;
329 m[0][1]=-2/kk*x12*y12;
330 m[0][2]=-2/kk*x12*z12;
331 m[1][0]=-2/kk*x12*y12;
332 m[1][1]=2-2/kk*y12*y12;
333 m[1][2]=-2/kk*y12*z12;
334 m[2][0]=-2/kk*x12*z12;
336 m[2][2]=2-2/kk*z12*z12;
337 d[0]=2*p0[0]-2/kk*p0[0]*x12*x12-2/kk*p0[2]*x12*z12-2/kk*p0[1]*x12*y12;
338 d[1]=2*p0[1]-2/kk*p0[1]*y12*y12-2/kk*p0[0]*x12*y12-2/kk*p0[2]*z12*y12;
339 d[2]=2*p0[2]-2/kk*p0[2]*z12*z12-2/kk*p0[0]*x12*z12-2/kk*p0[1]*z12*y12;
342 //--------------------------------------------------------------------------
343 void AliVertexerTracks::GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t *sigmasq,Double_t (*m)[3],Double_t *d)
346 Double_t x12=p1[0]-p0[0];
347 Double_t y12=p1[1]-p0[1];
348 Double_t z12=p1[2]-p0[2];
350 Double_t den= x12*x12*sigmasq[1]*sigmasq[2]+y12*y12*sigmasq[0]*sigmasq[2]+z12*z12*sigmasq[0]*sigmasq[1];
352 Double_t kk= 2*(x12*x12/sigmasq[0]+y12*y12/sigmasq[1]+z12*z12/sigmasq[2]);
355 cc[0]=-x12/sigmasq[0];
356 cc[1]=-y12/sigmasq[1];
357 cc[2]=-z12/sigmasq[2];
359 Double_t ww=(-p0[0]*x12*sigmasq[1]*sigmasq[2]-p0[1]*y12*sigmasq[0]*sigmasq[2]-p0[2]*z12*sigmasq[0]*sigmasq[1])/den;
361 Double_t ss= -p0[0]*cc[0]-p0[1]*cc[1]-p0[2]*cc[2];
364 aa[0]=x12*sigmasq[1]*sigmasq[2]/den;
365 aa[1]=y12*sigmasq[0]*sigmasq[2]/den;
366 aa[2]=z12*sigmasq[0]*sigmasq[1]/den;
368 m[0][0]=aa[0]*(aa[0]*kk+2*cc[0])+2*cc[0]*aa[0]+2/sigmasq[0];
369 m[0][1]=aa[1]*(aa[0]*kk+2*cc[0])+2*cc[1]*aa[0];
370 m[0][2]=aa[2]*(aa[0]*kk+2*cc[0])+2*cc[2]*aa[0];
372 m[1][0]=aa[0]*(aa[1]*kk+2*cc[1])+2*cc[0]*aa[1];
373 m[1][1]=aa[1]*(aa[1]*kk+2*cc[1])+2*cc[1]*aa[1]+2/sigmasq[1];
374 m[1][2]=aa[2]*(aa[1]*kk+2*cc[1])+2*cc[2]*aa[1];
376 m[2][0]=aa[0]*(aa[2]*kk+2*cc[2])+2*cc[0]*aa[2];
377 m[2][1]=aa[1]*(aa[2]*kk+2*cc[2])+2*cc[1]*aa[2];
378 m[2][2]=aa[2]*(aa[2]*kk+2*cc[2])+2*cc[2]*aa[2]+2/sigmasq[2];
380 d[0]=-ww*(aa[0]*kk+2*cc[0])-2*ss*aa[0]+2*p0[0]/sigmasq[0];
381 d[1]=-ww*(aa[1]*kk+2*cc[1])-2*ss*aa[1]+2*p0[1]/sigmasq[1];
382 d[2]=-ww*(aa[2]*kk+2*cc[2])-2*ss*aa[2]+2*p0[2]/sigmasq[2];
385 //--------------------------------------------------------------------------
386 Double_t AliVertexerTracks::GetStrLinMinDist(Double_t *p0,Double_t *p1,Double_t *x0)
389 Double_t x12=p0[0]-p1[0];
390 Double_t y12=p0[1]-p1[1];
391 Double_t z12=p0[2]-p1[2];
392 Double_t x10=p0[0]-x0[0];
393 Double_t y10=p0[1]-x0[1];
394 Double_t z10=p0[2]-x0[2];
395 return ((x10*x10+y10*y10+z10*z10)*(x12*x12+y12*y12+z12*z12)-(x10*x12+y10*y12+z10*z12)*(x10*x12+y10*y12+z10*z12))/(x12*x12+y12*y12+z12*z12);
397 //---------------------------------------------------------------------------
398 void AliVertexerTracks::OneTrackVertFinder()
400 // find vertex for events with 1 track, using DCA to nominal beam axis
401 if(fDebug) printf("Number of prepared tracks =%d - Call OneTrackVertFinder",fTrkArraySel.GetEntries());
402 AliExternalTrackParam *track1;
403 track1 = (AliExternalTrackParam*)fTrkArraySel.At(0);
404 Double_t field=GetFieldkG();
405 Double_t alpha=track1->GetAlpha();
406 Double_t mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1];
407 Double_t pos[3],dir[3];
408 track1->GetXYZAt(mindist,field,pos);
409 track1->GetPxPyPzAt(mindist,field,dir);
410 AliStrLine *line1 = new AliStrLine(pos,dir);
411 Double_t p1[3]={fNominalPos[0],fNominalPos[1],0.};
412 Double_t p2[3]={fNominalPos[0],fNominalPos[1],10.};
413 AliStrLine *zeta=new AliStrLine(p1,p2,kTRUE);
414 Double_t crosspoint[3]={0.,0.,0.};
417 Int_t retcode = zeta->Cross(line1,crosspoint);
419 sigma=line1->GetDistFromPoint(crosspoint);
424 fVert.SetXYZ(crosspoint);
425 fVert.SetDispersion(sigma);
426 fVert.SetNContributors(nContrib);
428 //---------------------------------------------------------------------------
429 void AliVertexerTracks::HelixVertexFinder()
431 // Get estimate of vertex position in (x,y) from tracks DCA
436 for(Int_t i=0;i<2;i++)initPos[i]=fNominalPos[i];
437 Double_t field=GetFieldkG();
439 Int_t nacc = (Int_t)fTrkArraySel.GetEntriesFast();
441 Double_t aver[3]={0.,0.,0.};
442 Double_t averquad[3]={0.,0.,0.};
443 Double_t sigmaquad[3]={0.,0.,0.};
446 AliExternalTrackParam *track1;
447 AliExternalTrackParam *track2;
450 Double_t alpha, cs, sn;
451 Double_t crosspoint[3];
452 for(Int_t i=0; i<nacc; i++){
453 track1 = (AliExternalTrackParam*)fTrkArraySel.At(i);
456 for(Int_t j=i+1; j<nacc; j++){
457 track2 = (AliExternalTrackParam*)fTrkArraySel.At(j);
459 distCA=track2->PropagateToDCA(track1,field);
460 if(fDCAcut<=0 ||(fDCAcut>0&&distCA<fDCAcut)){
462 alpha=track1->GetAlpha();
463 cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
464 Double_t x1=x*cs - track1->GetY()*sn;
465 Double_t y1=x*sn + track1->GetY()*cs;
466 Double_t z1=track1->GetZ();
468 Double_t sx1=sn*sn*track1->GetSigmaY2(), sy1=cs*cs*track1->GetSigmaY2();
470 alpha=track2->GetAlpha();
471 cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
472 Double_t x2=x*cs - track2->GetY()*sn;
473 Double_t y2=x*sn + track2->GetY()*cs;
474 Double_t z2=track2->GetZ();
475 Double_t sx2=sn*sn*track2->GetSigmaY2(), sy2=cs*cs*track2->GetSigmaY2();
476 Double_t sz1=track1->GetSigmaZ2(), sz2=track2->GetSigmaZ2();
477 Double_t wx1=sx2/(sx1+sx2), wx2=1.- wx1;
478 Double_t wy1=sy2/(sy1+sy2), wy2=1.- wy1;
479 Double_t wz1=sz2/(sz1+sz2), wz2=1.- wz1;
480 crosspoint[0]=wx1*x1 + wx2*x2;
481 crosspoint[1]=wy1*y1 + wy2*y2;
482 crosspoint[2]=wz1*z1 + wz2*z2;
485 for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj];
486 for(Int_t jj=0;jj<3;jj++)averquad[jj]+=(crosspoint[jj]*crosspoint[jj]);
492 for(Int_t jj=0;jj<3;jj++){
493 initPos[jj] = aver[jj]/ncombi;
494 averquad[jj]/=ncombi;
495 sigmaquad[jj]=averquad[jj]-initPos[jj]*initPos[jj];
496 sigma+=sigmaquad[jj];
498 sigma=TMath::Sqrt(TMath::Abs(sigma));
501 Warning("HelixVertexFinder","Finder did not succed");
504 fVert.SetXYZ(initPos);
505 fVert.SetDispersion(sigma);
506 fVert.SetNContributors(ncombi);
508 //----------------------------------------------------------------------------
509 Int_t AliVertexerTracks::PrepareTracks(TObjArray &trkArrayOrig,
514 // Propagate tracks to initial vertex position and store them in a TObjArray
516 if(fDebug) printf(" PrepareTracks()\n");
518 Int_t nTrksOrig = (Int_t)trkArrayOrig.GetEntriesFast();
521 Double_t maxd0z0 = (fITSrefit ? fMaxd0z0 : 10.*fMaxd0z0);
522 Double_t sigmaCurr[3];
523 Double_t normdistx,normdisty;
524 Double_t d0z0[2],covd0z0[3];
526 Double_t field = GetFieldkG();
528 AliESDVertex *initVertex = new AliESDVertex(fNominalPos,fNominalCov,1,1);
530 if(!fTrkArraySel.IsEmpty()) fTrkArraySel.Delete();
532 AliExternalTrackParam *track=0;
534 for(Int_t i=0; i<nTrksOrig; i++) {
535 track = new AliExternalTrackParam(*(AliExternalTrackParam*)trkArrayOrig.At(i));
536 // only TPC tracks in |eta|<0.9
537 if(!fITSrefit && TMath::Abs(track->GetTgl())>1.) {
538 if(fDebug) printf(" rejecting track with tgl = %f\n",track->GetTgl());
543 // propagate track to vertex
544 if(optImpParCut<2 || fOnlyFitter) { // optImpParCut==1 or 0
545 track->PropagateToDCA(initVertex,field,100.,d0z0,covd0z0);
546 } else { // optImpParCut==2
547 fCurrentVertex->GetSigmaXYZ(sigmaCurr);
548 normdistx = TMath::Abs(fCurrentVertex->GetXv()-fNominalPos[0])/TMath::Sqrt(sigmaCurr[0]*sigmaCurr[0]+fNominalCov[0]);
549 normdisty = TMath::Abs(fCurrentVertex->GetYv()-fNominalPos[1])/TMath::Sqrt(sigmaCurr[1]*sigmaCurr[1]+fNominalCov[2]);
550 if(normdistx < 3. && normdisty < 3. &&
551 (sigmaCurr[0]+sigmaCurr[1])<(TMath::Sqrt(fNominalCov[0])+TMath::Sqrt(fNominalCov[2]))) {
552 track->PropagateToDCA(fCurrentVertex,field,100.,d0z0,covd0z0);
554 track->PropagateToDCA(initVertex,field,100.,d0z0,covd0z0);
558 sigmad0 = TMath::Sqrt(covd0z0[0]);
559 maxd0rphi = fNSigma*sigmad0;
560 if(optImpParCut==1) maxd0rphi *= 5.;
561 //sigmad0z0 = TMath::Sqrt(covd0z0[0]+covd0z0[2]); // for future improvement
562 //maxd0z0 = 10.*fNSigma*sigmad0z0;
564 if(fDebug) printf("trk %d; id %d; |d0| = %f; d0 cut = %f; |z0| = %f; |d0|oplus|z0| = %f; d0z0 cut = %f\n",i,(Int_t)idOrig[i],TMath::Abs(d0z0[0]),maxd0rphi,TMath::Abs(d0z0[1]),TMath::Sqrt(d0z0[0]*d0z0[0]+d0z0[1]*d0z0[1]),maxd0z0);
566 // if fConstraint=kFALSE, during iterations 1 and 2 ||
567 // if fConstraint=kTRUE, during iteration 2,
568 // select tracks with d0oplusz0 < maxd0z0
569 if((!fConstraint && optImpParCut>0 && fVert.GetNContributors()>0) ||
570 ( fConstraint && optImpParCut==2)) {
572 TMath::Sqrt(d0z0[0]*d0z0[0]+d0z0[1]*d0z0[1])>maxd0z0) {
573 if(fDebug) printf(" rejected\n");
574 delete track; continue;
579 // select tracks with d0rphi < maxd0rphi
580 if(optImpParCut>0 && TMath::Abs(d0z0[0])>maxd0rphi) {
581 if(fDebug) printf(" rejected\n");
582 delete track; continue;
585 fTrkArraySel.AddLast(track);
586 fIdSel[nTrksSel] = idOrig[i];
594 //---------------------------------------------------------------------------
595 AliESDVertex* AliVertexerTracks::RemoveTracksFromVertex(AliESDVertex *inVtx,
601 // Removes tracks in trksTree from fit of inVtx
604 if(!strstr(inVtx->GetTitle(),"VertexerTracksWithConstraint")) {
605 printf("ERROR: primary vertex has no constraint: cannot remove tracks\n");
608 if(!strstr(inVtx->GetTitle(),"VertexerTracksWithConstraintOnlyFitter"))
609 printf("WARNING: result of tracks' removal will be only approximately correct\n");
612 rv(0,0) = inVtx->GetXv();
613 rv(1,0) = inVtx->GetYv();
614 rv(2,0) = inVtx->GetZv();
617 inVtx->GetCovMatrix(cov);
619 vV(0,1) = cov[1]; vV(1,0) = cov[1];
621 vV(0,2) = cov[3]; vV(2,0) = cov[3];
622 vV(1,2) = cov[4]; vV(2,1) = cov[4];
625 TMatrixD sumWi(TMatrixD::kInverted,vV);
626 TMatrixD sumWiri(sumWi,TMatrixD::kMult,rv);
628 Int_t nUsedTrks = inVtx->GetNIndices();
629 Double_t chi2 = inVtx->GetChi2();
631 AliExternalTrackParam *track = 0;
632 Int_t ntrks = (Int_t)trkArray->GetEntriesFast();
633 for(Int_t i=0;i<ntrks;i++) {
634 track = (AliExternalTrackParam*)trkArray->At(i);
635 if(!inVtx->UsesTrack(id[i])) {
636 printf("track %d was not used in vertex fit\n",id[i]);
639 Double_t alpha = track->GetAlpha();
640 Double_t xl = diamondxy[0]*TMath::Cos(alpha)+diamondxy[1]*TMath::Sin(alpha);
641 track->PropagateTo(xl,GetFieldkG());
642 // vector of track global coordinates
644 // covariance matrix of ri
647 // get space point from track
648 if(!TrackToPoint(track,ri,wWi)) continue;
650 TMatrixD wWiri(wWi,TMatrixD::kMult,ri);
656 TMatrixD deltar = rv; deltar -= ri;
657 TMatrixD wWideltar(wWi,TMatrixD::kMult,deltar);
658 Double_t chi2i = deltar(0,0)*wWideltar(0,0)+
659 deltar(1,0)*wWideltar(1,0)+
660 deltar(2,0)*wWideltar(2,0);
661 // remove from total chi2
666 printf("Trying to remove too many tracks!\n");
674 // new inverted of weights matrix
675 TMatrixD invsumWi(TMatrixD::kInverted,sumWi);
677 // new position of primary vertex
678 rvnew.Mult(vVnew,sumWiri);
680 Double_t position[3];
681 position[0] = rvnew(0,0);
682 position[1] = rvnew(1,0);
683 position[2] = rvnew(2,0);
691 // store data in the vertex object
692 AliESDVertex *outVtx = new AliESDVertex(position,cov,chi2,nUsedTrks);
693 outVtx->SetTitle(inVtx->GetTitle());
694 UShort_t *inindices = inVtx->GetIndices();
695 Int_t nIndices = nUsedTrks;
696 UShort_t *outindices = new UShort_t[nIndices];
698 for(Int_t k=0; k<inVtx->GetNIndices(); k++) {
699 Bool_t copyindex=kTRUE;
700 for(Int_t l=0; l<ntrks; l++) {
701 if(inindices[k]==id[l]) copyindex=kFALSE;
704 outindices[j] = inindices[k]; j++;
707 outVtx->SetIndices(nIndices,outindices);
708 delete [] outindices;
711 printf("Vertex before removing tracks:\n");
712 inVtx->PrintStatus();
713 inVtx->PrintIndices();
714 printf("Vertex after removing tracks:\n");
715 outVtx->PrintStatus();
716 outVtx->PrintIndices();
721 //---------------------------------------------------------------------------
722 void AliVertexerTracks::SetSkipTracks(Int_t n,Int_t *skipped)
725 // Mark the tracks not to be used in the vertex reconstruction.
726 // Tracks are identified by AliESDtrack::GetID()
728 fNTrksToSkip = n; fTrksToSkip = new Int_t[n];
729 for(Int_t i=0;i<n;i++) fTrksToSkip[i] = skipped[i];
732 //---------------------------------------------------------------------------
733 void AliVertexerTracks::SetVtxStart(AliESDVertex *vtx)
736 // Set initial vertex knowledge
738 vtx->GetXYZ(fNominalPos);
739 vtx->GetCovMatrix(fNominalCov);
743 //---------------------------------------------------------------------------
744 void AliVertexerTracks::StrLinVertexFinderMinDist(Int_t optUseWeights)
746 AliExternalTrackParam *track1;
747 Double_t field=GetFieldkG();
748 const Int_t knacc = (Int_t)fTrkArraySel.GetEntriesFast();
749 TClonesArray *linarray = new TClonesArray("AliStrLine",1000);
750 TClonesArray &lines = *linarray;
751 for(Int_t i=0; i<knacc; i++){
752 track1 = (AliExternalTrackParam*)fTrkArraySel.At(i);
753 Double_t alpha=track1->GetAlpha();
754 Double_t mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1];
755 Double_t pos[3],dir[3],sigmasq[3];
756 track1->GetXYZAt(mindist,field,pos);
757 track1->GetPxPyPzAt(mindist,field,dir);
758 sigmasq[0]=TMath::Sin(alpha)*TMath::Sin(alpha)*track1->GetSigmaY2();
759 sigmasq[1]=TMath::Cos(alpha)*TMath::Cos(alpha)*track1->GetSigmaY2();
760 sigmasq[2]=track1->GetSigmaZ2();
763 if(!TrackToPoint(track1,ri,wWi)) continue;
766 for(Int_t ia=0;ia<3;ia++){
767 for(Int_t ib=0;ib<3;ib++){
768 wmat[iel]=wWi(ia,ib);
772 new(lines[i]) AliStrLine(pos,sigmasq,wmat,dir);
774 fVert=TrackletVertexFinder(linarray,optUseWeights);
778 //---------------------------------------------------------------------------
779 AliESDVertex AliVertexerTracks::TrackletVertexFinder(TClonesArray *lines, Int_t optUseWeights)
781 // Calculate the point at minimum distance to prepared tracks
783 const Int_t knacc = (Int_t)lines->GetEntriesFast();
784 Double_t initPos[3]={0.,0.,0.};
786 Double_t (*vectP0)[3]=new Double_t [knacc][3];
787 Double_t (*vectP1)[3]=new Double_t [knacc][3];
790 Double_t dsum[3]={0,0,0};
792 for(Int_t i=0;i<3;i++){
793 for(Int_t j=0;j<3;j++){
799 for(Int_t i=0; i<knacc; i++){
800 AliStrLine* line1 = (AliStrLine*)lines->At(i);
801 if (!line1) continue;
802 Double_t p0[3],cd[3],sigmasq[3];
806 line1->GetSigma2P0(sigmasq);
807 line1->GetWMatrix(wmat);
810 for(Int_t ia=0;ia<3;ia++){
811 for(Int_t ib=0;ib<3;ib++){
812 wWi(ia,ib)=wmat[iel];
819 Double_t p1[3]={p0[0]+cd[0],p0[1]+cd[1],p0[2]+cd[2]};
829 if(optUseWeights==0)GetStrLinDerivMatrix(p0,p1,matr,dknow);
830 else GetStrLinDerivMatrix(p0,p1,sigmasq,matr,dknow);
833 for(Int_t iii=0;iii<3;iii++){
834 dsum[iii]+=dknow[iii];
835 for(Int_t lj=0;lj<3;lj++) sum[iii][lj]+=matr[iii][lj];
839 TMatrixD invsumWi(TMatrixD::kInverted,sumWi);
840 Double_t covmatrix[6];
841 covmatrix[0] = invsumWi(0,0);
842 covmatrix[1] = invsumWi(0,1);
843 covmatrix[2] = invsumWi(1,1);
844 covmatrix[3] = invsumWi(0,2);
845 covmatrix[4] = invsumWi(1,2);
846 covmatrix[5] = invsumWi(2,2);
849 Double_t det=GetDeterminant3X3(sum);
853 for(Int_t zz=0;zz<3;zz++){
854 for(Int_t ww=0;ww<3;ww++){
855 for(Int_t kk=0;kk<3;kk++) vett[ww][kk]=sum[ww][kk];
857 for(Int_t kk=0;kk<3;kk++) vett[kk][zz]=dsum[kk];
858 initPos[zz]=GetDeterminant3X3(vett)/det;
862 for(Int_t i=0; i<knacc; i++){
863 Double_t p0[3]={0,0,0},p1[3]={0,0,0};
864 for(Int_t ii=0;ii<3;ii++){
865 p0[ii]=vectP0[i][ii];
866 p1[ii]=vectP1[i][ii];
868 sigma+=GetStrLinMinDist(p0,p1,initPos);
871 sigma=TMath::Sqrt(sigma);
875 AliESDVertex theVert(initPos,covmatrix,99999.,knacc);
876 theVert.SetDispersion(sigma);
881 //---------------------------------------------------------------------------
882 Bool_t AliVertexerTracks::TrackToPoint(AliExternalTrackParam *t,
883 TMatrixD &ri,TMatrixD &wWi,
884 Bool_t uUi3by3) const
887 // Extract from the AliExternalTrackParam the global coordinates ri and covariance matrix
888 // wWi of the space point that it represents (to be used in VertexFitter())
892 Double_t rotAngle = t->GetAlpha();
893 if(rotAngle<0.) rotAngle += 2.*TMath::Pi();
894 Double_t cosRot = TMath::Cos(rotAngle);
895 Double_t sinRot = TMath::Sin(rotAngle);
897 ri(0,0) = t->GetX()*cosRot-t->GetY()*sinRot;
898 ri(1,0) = t->GetX()*sinRot+t->GetY()*cosRot;
904 // matrix to go from global (x,y,z) to local (y,z);
913 // covariance matrix of local (y,z) - inverted
915 uUi(0,0) = t->GetSigmaY2();
916 uUi(0,1) = t->GetSigmaZY();
917 uUi(1,0) = t->GetSigmaZY();
918 uUi(1,1) = t->GetSigmaZ2();
920 //printf(" %f %f\n",uUi(0,0),uUi(0,1));
921 //printf(" %f %f\n",uUi(1,0),uUi(1,1));
923 if(uUi.Determinant() <= 0.) return kFALSE;
924 TMatrixD uUiInv(TMatrixD::kInverted,uUi);
926 // weights matrix: wWi = qQiT * uUiInv * qQi
927 TMatrixD uUiInvQi(uUiInv,TMatrixD::kMult,qQi);
928 TMatrixD m(qQi,TMatrixD::kTransposeMult,uUiInvQi);
931 if(fVert.GetNContributors()<1) AliFatal("Vertex from finder is empty");
932 // matrix to go from global (x,y,z) to local (x,y,z);
944 // covariance of fVert along the track
945 Double_t p[3],pt,ptot;
947 pt = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]);
948 ptot = TMath::Sqrt(pt*pt+p[2]*p[2]);
949 Double_t cphi = p[0]/pt; //cos(phi)=px/pt
950 Double_t sphi = p[1]/pt; //sin(phi)=py/pt
951 Double_t clambda = pt/ptot; //cos(lambda)=pt/ptot
952 Double_t slambda = p[2]/ptot; //sin(lambda)=pz/ptot
953 Double_t covfVert[6];
954 fVert.GetCovMatrix(covfVert);
955 Double_t covfVertalongt =
956 covfVert[0]*cphi*cphi*clambda*clambda
957 +covfVert[1]*2.*cphi*sphi*clambda*clambda
958 +covfVert[3]*2.*cphi*clambda*slambda
959 +covfVert[2]*sphi*sphi*clambda*clambda
960 +covfVert[4]*2.*sphi*clambda*slambda
961 +covfVert[5]*slambda*slambda;
962 // covariance matrix of local (x,y,z) - inverted
964 uUi(0,0) = covfVertalongt * fnSigmaForUi00 * fnSigmaForUi00;
965 if(fDebug) printf("=====> sqrtUi00 cm %f\n",TMath::Sqrt(uUi(0,0)));
969 uUi(1,1) = t->GetSigmaY2();
970 uUi(1,2) = t->GetSigmaZY();
972 uUi(2,1) = t->GetSigmaZY();
973 uUi(2,2) = t->GetSigmaZ2();
975 //printf(" %f %f\n",uUi(0,0),uUi(0,1));
976 //printf(" %f %f\n",uUi(1,0),uUi(1,1));
978 if(uUi.Determinant() <= 0.) return kFALSE;
979 TMatrixD uUiInv(TMatrixD::kInverted,uUi);
981 // weights matrix: wWi = qQiT * uUiInv * qQi
982 TMatrixD uUiInvQi(uUiInv,TMatrixD::kMult,qQi);
983 TMatrixD m(qQi,TMatrixD::kTransposeMult,uUiInvQi);
990 //---------------------------------------------------------------------------
991 void AliVertexerTracks::TooFewTracks()
994 // When the number of tracks is < fMinTracks,
995 // deal with vertices not found and prepare to exit
997 if(fDebug) printf("TooFewTracks\n");
999 Double_t pos[3],err[3];
1000 pos[0] = fNominalPos[0];
1001 err[0] = TMath::Sqrt(fNominalCov[0]);
1002 pos[1] = fNominalPos[1];
1003 err[1] = TMath::Sqrt(fNominalCov[2]);
1004 pos[2] = fNominalPos[2];
1005 err[2] = TMath::Sqrt(fNominalCov[5]);
1006 Int_t ncontr = (err[0]>1. ? -1 : -3);
1008 fCurrentVertex = new AliESDVertex(pos,err);
1009 fCurrentVertex->SetNContributors(ncontr);
1012 fCurrentVertex->SetTitle("VertexerTracksWithConstraint");
1014 fCurrentVertex->SetTitle("VertexerTracksNoConstraint");
1017 if(!fTrkArraySel.IsEmpty()) fTrkArraySel.Delete();
1018 if(fIdSel) {delete [] fIdSel; fIdSel=NULL;}
1019 if(fTrksToSkip) {delete [] fTrksToSkip; fTrksToSkip=NULL;}
1023 //---------------------------------------------------------------------------
1024 void AliVertexerTracks::VertexFinder(Int_t optUseWeights)
1027 // Get estimate of vertex position in (x,y) from tracks DCA
1029 Double_t initPos[3];
1031 for(Int_t i=0;i<2;i++)initPos[i]=fNominalPos[i];
1032 Int_t nacc = (Int_t)fTrkArraySel.GetEntriesFast();
1033 Double_t aver[3]={0.,0.,0.};
1034 Double_t aversq[3]={0.,0.,0.};
1035 Double_t sigmasq[3]={0.,0.,0.};
1038 AliExternalTrackParam *track1;
1039 AliExternalTrackParam *track2;
1040 Double_t pos[3],dir[3];
1041 Double_t alpha,mindist;
1042 Double_t field=GetFieldkG();
1044 for(Int_t i=0; i<nacc; i++){
1045 track1 = (AliExternalTrackParam*)fTrkArraySel.At(i);
1046 alpha=track1->GetAlpha();
1047 mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1];
1048 track1->GetXYZAt(mindist,field,pos);
1049 track1->GetPxPyPzAt(mindist,field,dir);
1050 AliStrLine *line1 = new AliStrLine(pos,dir);
1052 // AliStrLine *line1 = new AliStrLine();
1053 // track1->ApproximateHelixWithLine(mindist,field,line1);
1055 for(Int_t j=i+1; j<nacc; j++){
1056 track2 = (AliExternalTrackParam*)fTrkArraySel.At(j);
1057 alpha=track2->GetAlpha();
1058 mindist = TMath::Cos(alpha)*fNominalPos[0]+TMath::Sin(alpha)*fNominalPos[1];
1059 track2->GetXYZAt(mindist,field,pos);
1060 track2->GetPxPyPzAt(mindist,field,dir);
1061 AliStrLine *line2 = new AliStrLine(pos,dir);
1062 // AliStrLine *line2 = new AliStrLine();
1063 // track2->ApproximateHelixWithLine(mindist,field,line2);
1064 Double_t distCA=line2->GetDCA(line1);
1065 //printf("%d %d %f\n",i,j,distCA);
1066 if(fDCAcut<=0 || (fDCAcut>0&&distCA<fDCAcut)){
1067 Double_t pnt1[3],pnt2[3],crosspoint[3];
1069 if(optUseWeights<=0){
1070 Int_t retcode = line2->Cross(line1,crosspoint);
1073 for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj];
1074 for(Int_t jj=0;jj<3;jj++)aversq[jj]+=(crosspoint[jj]*crosspoint[jj]);
1077 if(optUseWeights>0){
1078 Int_t retcode = line1->CrossPoints(line2,pnt1,pnt2);
1081 alpha=track1->GetAlpha();
1082 cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
1083 Double_t sx1=sn*sn*track1->GetSigmaY2(), sy1=cs*cs*track1->GetSigmaY2();
1084 alpha=track2->GetAlpha();
1085 cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
1086 Double_t sx2=sn*sn*track2->GetSigmaY2(), sy2=cs*cs*track2->GetSigmaY2();
1087 Double_t sz1=track1->GetSigmaZ2(), sz2=track2->GetSigmaZ2();
1088 Double_t wx1=sx2/(sx1+sx2), wx2=1.- wx1;
1089 Double_t wy1=sy2/(sy1+sy2), wy2=1.- wy1;
1090 Double_t wz1=sz2/(sz1+sz2), wz2=1.- wz1;
1091 crosspoint[0]=wx1*pnt1[0] + wx2*pnt2[0];
1092 crosspoint[1]=wy1*pnt1[1] + wy2*pnt2[1];
1093 crosspoint[2]=wz1*pnt1[2] + wz2*pnt2[2];
1096 for(Int_t jj=0;jj<3;jj++)aver[jj]+=crosspoint[jj];
1097 for(Int_t jj=0;jj<3;jj++)aversq[jj]+=(crosspoint[jj]*crosspoint[jj]);
1106 for(Int_t jj=0;jj<3;jj++){
1107 initPos[jj] = aver[jj]/ncombi;
1108 //printf("%f\n",initPos[jj]);
1110 sigmasq[jj]=aversq[jj]-initPos[jj]*initPos[jj];
1113 sigma=TMath::Sqrt(TMath::Abs(sigma));
1116 Warning("VertexFinder","Finder did not succed");
1119 fVert.SetXYZ(initPos);
1120 fVert.SetDispersion(sigma);
1121 fVert.SetNContributors(ncombi);
1123 //---------------------------------------------------------------------------
1124 void AliVertexerTracks::VertexFitter()
1127 // The optimal estimate of the vertex position is given by a "weighted
1128 // average of tracks positions".
1129 // Original method: V. Karimaki, CMS Note 97/0051
1131 Bool_t useConstraint = fConstraint;
1132 Double_t initPos[3];
1134 fVert.GetXYZ(initPos);
1136 initPos[0]=fNominalPos[0];
1137 initPos[1]=fNominalPos[1];
1138 initPos[2]=fNominalPos[2];
1141 Int_t nTrksSel = (Int_t)fTrkArraySel.GetEntries();
1142 if(nTrksSel==1) useConstraint=kTRUE;
1144 printf("--- VertexFitter(): start\n");
1145 printf(" Number of tracks in array: %d\n",nTrksSel);
1146 printf(" Minimum # tracks required in fit: %d\n",fMinTracks);
1147 printf(" Vertex position after finder: %f,%f,%f\n",initPos[0],initPos[1],initPos[2]);
1148 if(useConstraint) printf(" This vertex will be used in fit: (%f+-%f,%f+-%f)\n",fNominalPos[0],TMath::Sqrt(fNominalCov[0]),fNominalPos[1],TMath::Sqrt(fNominalCov[2]));
1151 // special treatment for few-tracks fits (e.g. secondary vertices)
1152 Bool_t uUi3by3 = kFALSE; if(nTrksSel<5 && !useConstraint) uUi3by3 = kTRUE;
1157 rv(0,0) = initPos[0];
1158 rv(1,0) = initPos[1];
1160 Double_t xlStart,alpha;
1162 Double_t chi2,chi2i,chi2b;
1163 AliExternalTrackParam *t = 0;
1166 // initial vertex covariance matrix
1168 vVb(0,0) = fNominalCov[0];
1169 vVb(0,1) = fNominalCov[1];
1171 vVb(1,0) = fNominalCov[1];
1172 vVb(1,1) = fNominalCov[2];
1176 vVb(2,2) = fNominalCov[5];
1177 TMatrixD vVbInv(TMatrixD::kInverted,vVb);
1179 rb(0,0) = fNominalPos[0];
1180 rb(1,0) = fNominalPos[1];
1181 rb(2,0) = fNominalPos[2];
1182 TMatrixD vVbInvrb(vVbInv,TMatrixD::kMult,rb);
1186 // 1st - estimate of vtx using all tracks
1187 // 2nd - estimate of global chi2
1188 for(step=0; step<2; step++) {
1189 if(fDebug) printf(" step = %d\n",step);
1193 if(step==1) { initPos[0]=rv(0,0); initPos[0]=rv(1,0); }
1195 TMatrixD sumWiri(3,1);
1196 TMatrixD sumWi(3,3);
1197 for(i=0; i<3; i++) {
1199 for(j=0; j<3; j++) sumWi(j,i) = 0.;
1202 // mean vertex constraint
1205 sumWiri(i,0) += vVbInvrb(i,0);
1206 for(k=0;k<3;k++) sumWi(i,k) += vVbInv(i,k);
1209 TMatrixD deltar = rv; deltar -= rb;
1210 TMatrixD vVbInvdeltar(vVbInv,TMatrixD::kMult,deltar);
1211 chi2b = deltar(0,0)*vVbInvdeltar(0,0)+
1212 deltar(1,0)*vVbInvdeltar(1,0)+
1213 deltar(2,0)*vVbInvdeltar(2,0);
1218 for(k=0; k<nTrksSel; k++) {
1219 // get track from track array
1220 t = (AliExternalTrackParam*)fTrkArraySel.At(k);
1221 alpha = t->GetAlpha();
1222 xlStart = initPos[0]*TMath::Cos(alpha)+initPos[1]*TMath::Sin(alpha);
1223 // to vtxSeed (from finder)
1224 t->PropagateTo(xlStart,GetFieldkG());
1226 // vector of track global coordinates
1228 // covariance matrix of ri
1231 // get space point from track
1232 if(!TrackToPoint(t,ri,wWi,uUi3by3)) continue;
1233 TMatrixD wWiri(wWi,TMatrixD::kMult,ri);
1236 TMatrixD deltar = rv; deltar -= ri;
1237 TMatrixD wWideltar(wWi,TMatrixD::kMult,deltar);
1238 chi2i = deltar(0,0)*wWideltar(0,0)+
1239 deltar(1,0)*wWideltar(1,0)+
1240 deltar(2,0)*wWideltar(2,0);
1242 // add to total chi2
1249 } // end loop on tracks
1251 if(nTrksUsed < fMinTracks) {
1256 Double_t determinant = sumWi.Determinant();
1257 //cerr<<" determinant: "<<determinant<<endl;
1258 if(determinant < 100.) {
1259 printf("det(V) = 0\n");
1265 // inverted of weights matrix
1266 TMatrixD invsumWi(TMatrixD::kInverted,sumWi);
1268 // position of primary vertex
1269 rv.Mult(vV,sumWiri);
1271 } // end loop on the 2 steps
1278 Double_t position[3];
1279 position[0] = rv(0,0);
1280 position[1] = rv(1,0);
1281 position[2] = rv(2,0);
1282 Double_t covmatrix[6];
1283 covmatrix[0] = vV(0,0);
1284 covmatrix[1] = vV(0,1);
1285 covmatrix[2] = vV(1,1);
1286 covmatrix[3] = vV(0,2);
1287 covmatrix[4] = vV(1,2);
1288 covmatrix[5] = vV(2,2);
1290 // for correct chi2/ndf, count constraint as additional "track"
1291 if(fConstraint) nTrksUsed++;
1292 // store data in the vertex object
1293 fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nTrksUsed);
1296 printf(" Vertex after fit:\n");
1297 fCurrentVertex->PrintStatus();
1298 printf("--- VertexFitter(): finish\n");
1303 //----------------------------------------------------------------------------
1304 AliESDVertex* AliVertexerTracks::VertexForSelectedTracks(TObjArray *trkArray,
1306 Bool_t optUseFitter,
1307 Bool_t optPropagate)
1310 // Return vertex from tracks (AliExternalTrackParam) in array
1315 // get tracks and propagate them to initial vertex position
1316 fIdSel = new UShort_t[(Int_t)trkArray->GetEntriesFast()];
1317 Int_t nTrksSel = PrepareTracks(*trkArray,id,0);
1318 if(nTrksSel < TMath::Max(2,fMinTracks)) {
1320 return fCurrentVertex;
1325 case 1: StrLinVertexFinderMinDist(1); break;
1326 case 2: StrLinVertexFinderMinDist(0); break;
1327 case 3: HelixVertexFinder(); break;
1328 case 4: VertexFinder(1); break;
1329 case 5: VertexFinder(0); break;
1330 default: printf("Wrong algorithm\n"); break;
1332 if(fDebug) printf(" Vertex finding completed\n");
1338 Double_t position[3]={fVert.GetXv(),fVert.GetYv(),fVert.GetZv()};
1339 Double_t covmatrix[6];
1340 fVert.GetCovMatrix(covmatrix);
1341 Double_t chi2=99999.;
1342 Int_t nTrksUsed=fVert.GetNContributors();
1343 fCurrentVertex = new AliESDVertex(position,covmatrix,chi2,nTrksUsed);
1345 fCurrentVertex->SetDispersion(fVert.GetDispersion());
1348 // set indices of used tracks and propagate track to found vertex
1349 UShort_t *indices = 0;
1350 Double_t d0z0[2],covd0z0[3];
1351 AliExternalTrackParam *t = 0;
1352 if(fCurrentVertex->GetNContributors()>0) {
1353 indices = new UShort_t[fCurrentVertex->GetNContributors()];
1354 for(Int_t jj=0; jj<(Int_t)fTrkArraySel.GetEntriesFast(); jj++) {
1355 indices[jj] = fIdSel[jj];
1356 t = (AliExternalTrackParam*)fTrkArraySel.At(jj);
1357 if(optPropagate && optUseFitter) {
1358 if(TMath::Sqrt(fCurrentVertex->GetXv()*fCurrentVertex->GetXv()+fCurrentVertex->GetYv()*fCurrentVertex->GetYv())<3.) {
1359 t->PropagateToDCA(fCurrentVertex,GetFieldkG(),100.,d0z0,covd0z0);
1360 if(fDebug) printf("Track %d propagated to found vertex\n",jj);
1362 AliWarning("Found vertex outside beam pipe!");
1366 fCurrentVertex->SetIndices(fCurrentVertex->GetNContributors(),indices);
1370 delete [] indices; indices=NULL;
1371 delete [] fIdSel; fIdSel=NULL;
1372 fTrkArraySel.Delete();
1374 return fCurrentVertex;
1376 //----------------------------------------------------------------------------
1377 AliESDVertex* AliVertexerTracks::VertexForSelectedESDTracks(TObjArray *trkArray,
1378 Bool_t optUseFitter,
1379 Bool_t optPropagate)
1382 // Return vertex from array of ESD tracks
1385 Int_t nTrks = (Int_t)trkArray->GetEntriesFast();
1386 UShort_t *id = new UShort_t[nTrks];
1388 AliESDtrack *esdt = 0;
1389 for(Int_t i=0; i<nTrks; i++){
1390 esdt = (AliESDtrack*)trkArray->At(i);
1391 id[i] = (UShort_t)esdt->GetID();
1394 VertexForSelectedTracks(trkArray,id,optUseFitter,optPropagate);
1396 delete [] id; id=NULL;
1398 return fCurrentVertex;
1400 //--------------------------------------------------------------------------