[u/mrichter/AliRoot.git] / ITS / AliITSVertexer3D.cxx

/**************************************************************************
 * Copyright(c) 2006-2008, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/
#include <AliESDVertex.h>
#include <AliITSVertexer3D.h>
#include <AliStrLine.h>
#include <AliVertexerTracks.h>
#include <Riostream.h>
#include <TH3F.h>
#include <TTree.h>
#include<TClonesArray.h>
#include "AliRunLoader.h"
#include "AliITSLoader.h"
#include "AliITSgeom.h"
#include "AliITSDetTypeRec.h"
#include "AliITSRecPoint.h"
/////////////////////////////////////////////////////////////////
// this class implements a method to determine
// the 3 coordinates of the primary vertex
// for p-p collisions 
// It can be used successfully with Pb-Pb collisions
////////////////////////////////////////////////////////////////

ClassImp(AliITSVertexer3D)

//______________________________________________________________________
AliITSVertexer3D::AliITSVertexer3D():AliITSVertexer(),
fLines(),
fVert3D(),
fCoarseDiffPhiCut(0.),
fCoarseMaxRCut(0.),
fMaxRCut(0.),
fZCutDiamond(0.),
fMaxZCut(0.),
fDCAcut(0.),
fDiffPhiMax(0.) {
  // Default constructor
  SetCoarseDiffPhiCut();
  SetCoarseMaxRCut();
  SetMaxRCut();
  SetZCutDiamond();
  SetMaxZCut();
  SetDCAcut();
  SetDiffPhiMax();

}

//______________________________________________________________________
AliITSVertexer3D::AliITSVertexer3D(TString fn): AliITSVertexer(fn),
fLines(),
fVert3D(),
fCoarseDiffPhiCut(0.),     
fCoarseMaxRCut(0.),
fMaxRCut(0.),
fZCutDiamond(0.),
fMaxZCut(0.),
fDCAcut(0.),
fDiffPhiMax(0.)  {
  // Standard constructor
  fLines = new TClonesArray("AliStrLine",1000);
  SetCoarseDiffPhiCut();
  SetCoarseMaxRCut();
  SetMaxRCut();
  SetZCutDiamond();
  SetMaxZCut();
  SetDCAcut();
  SetDiffPhiMax();
}

//______________________________________________________________________
AliITSVertexer3D::~AliITSVertexer3D() {
  // Destructor
  fVert3D = 0;  // this object is not owned by this class
  if(fLines){
    fLines->Delete();
    delete fLines;
  }
}

//______________________________________________________________________
AliESDVertex* AliITSVertexer3D::FindVertexForCurrentEvent(Int_t evnumber){
  // Defines the AliESDVertex for the current event
  if (fDebug) cout<<"\n \n FindVertexForCurrentEvent - 3D - PROCESSING EVENT "<<evnumber<<endl;
  fVert3D = 0;
  if(fLines)fLines->Clear();

  Int_t nolines = FindTracklets(evnumber,0);
  fCurrentVertex = 0;
  if(nolines<2)return fCurrentVertex;
  Int_t rc=Prepare3DVertex(0);
  if(rc==0)Find3DVertex();
  if(fVert3D){
    if(fLines) fLines->Delete();
    nolines = FindTracklets(evnumber,1);
    if(nolines>=2){
      rc=Prepare3DVertex(1);
      if(rc==0)Find3DVertex();
    }
  }
  
  if(fVert3D){
    fCurrentVertex = new AliESDVertex();
    fCurrentVertex->SetTitle("vertexer: 3D");
    fCurrentVertex->SetName("Vertex");
    fCurrentVertex->SetXv(fVert3D->GetXv());
    fCurrentVertex->SetYv(fVert3D->GetYv());
    fCurrentVertex->SetZv(fVert3D->GetZv());
    fCurrentVertex->SetDispersion(fVert3D->GetDispersion());
    fCurrentVertex->SetNContributors(fVert3D->GetNContributors());
  }
  FindMultiplicity(evnumber);
  return fCurrentVertex;
}  

//______________________________________________________________________
Int_t AliITSVertexer3D::FindTracklets(Int_t evnumber, Int_t optCuts){
  // All the possible combinations between recpoints on layer 1and 2 are
  // considered. Straight lines (=tracklets)are formed. 
  // The tracklets are processed in Prepare3DVertex
  AliRunLoader *rl =AliRunLoader::GetRunLoader();
  AliITSLoader* itsLoader = (AliITSLoader*)rl->GetLoader("ITSLoader");
  AliITSgeom* geom = itsLoader->GetITSgeom();
  itsLoader->LoadRecPoints();
  rl->GetEvent(evnumber);

  AliITSDetTypeRec detTypeRec;

  TTree *tR = itsLoader->TreeR();
  detTypeRec.SetTreeAddressR(tR);
  TClonesArray *itsRec  = 0;
  // lc and gc are local and global coordinates for layer 1
  Float_t lc[3]; for(Int_t ii=0; ii<3; ii++) lc[ii]=0.;
  Float_t gc[3]; for(Int_t ii=0; ii<3; ii++) gc[ii]=0.;
  // lc2 and gc2 are local and global coordinates for layer 2
  Float_t lc2[3]; for(Int_t ii=0; ii<3; ii++) lc2[ii]=0.;
  Float_t gc2[3]; for(Int_t ii=0; ii<3; ii++) gc2[ii]=0.;

  itsRec = detTypeRec.RecPoints();
  TBranch *branch;
  branch = tR->GetBranch("ITSRecPoints");

  // Set values for cuts
  Float_t xbeam=0., ybeam=0.;
  Float_t zvert=0.;
  Float_t deltaPhi=fCoarseDiffPhiCut;
  Float_t deltaR=fCoarseMaxRCut;
  Float_t dZmax=fZCutDiamond;
  if(optCuts){
    xbeam=fVert3D->GetXv();
    ybeam=fVert3D->GetYv();
    zvert=fVert3D->GetZv();
    deltaPhi = fDiffPhiMax; 
    deltaR=fMaxRCut;
    dZmax=fMaxZCut;
  }
  Int_t nrpL1 = 0;    // number of rec points on layer 1
  Int_t nrpL2 = 0;    // number of rec points on layer 2

  // By default irstL1=0 and lastL1=79
  Int_t irstL1 = geom->GetStartDet(0);
  Int_t lastL1 = geom->GetModuleIndex(2,1,1)-1;
  for(Int_t module= irstL1; module<=lastL1;module++){  // count number of recopints on layer 1
    branch->GetEvent(module);
    nrpL1+= itsRec->GetEntries();
    detTypeRec.ResetRecPoints();
  }
  //By default irstL2=80 and lastL2=239
  Int_t irstL2 = geom->GetModuleIndex(2,1,1);
  Int_t lastL2 = geom->GetLastDet(0);
  for(Int_t module= irstL2; module<=lastL2;module++){  // count number of recopints on layer 2
    branch->GetEvent(module);
    nrpL2+= itsRec->GetEntries();
    detTypeRec.ResetRecPoints();
  }
  if(nrpL1 == 0 || nrpL2 == 0){
    itsLoader->UnloadRecPoints();
    return -1;
  }
  if(fDebug) printf("RecPoints on Layer 1,2 = %d, %d\n",nrpL1,nrpL2);

  Double_t a[3]={xbeam,ybeam,0.}; 
  Double_t b[3]={xbeam,ybeam,10.};
  AliStrLine zeta(a,b,kTRUE);

  Int_t nolines = 0;
  // Loop on modules of layer 1
  for(Int_t modul1= irstL1; modul1<=lastL1;modul1++){   // Loop on modules of layer 1
    branch->GetEvent(modul1);
    Int_t nrecp1 = itsRec->GetEntries();
    TClonesArray *prpl1 = new TClonesArray("AliITSRecPoint",nrecp1);
    prpl1->SetOwner();
    TClonesArray &rpl1 = *prpl1;
    for(Int_t j=0;j<nrecp1;j++){
      AliITSRecPoint *recp = (AliITSRecPoint*)itsRec->At(j);
      new(rpl1[j])AliITSRecPoint(*recp);
    }
    detTypeRec.ResetRecPoints();
    for(Int_t j=0;j<nrecp1;j++){
      AliITSRecPoint *recp = (AliITSRecPoint*)prpl1->At(j);
      // Local coordinates of this recpoint
      lc[0]=recp->GetDetLocalX();
      lc[2]=recp->GetDetLocalZ();
      geom->LtoG(modul1,lc,gc); // global coordinates
      Double_t phi1 = TMath::ATan2(gc[1]-ybeam,gc[0]-xbeam);
      if(phi1<0)phi1=2*TMath::Pi()+phi1;
      for(Int_t modul2= irstL2; modul2<=lastL2;modul2++){
	branch->GetEvent(modul2);
	Int_t nrecp2 = itsRec->GetEntries();
	for(Int_t j2=0;j2<nrecp2;j2++){
	  recp = (AliITSRecPoint*)itsRec->At(j2);
	  lc2[0]=recp->GetDetLocalX();
	  lc2[2]=recp->GetDetLocalZ();
	  geom->LtoG(modul2,lc2,gc2);
	  Double_t phi2 = TMath::ATan2(gc2[1]-ybeam,gc2[0]-xbeam);
	  if(phi2<0)phi2=2*TMath::Pi()+phi2;
          Double_t diff = TMath::Abs(phi2-phi1); 
          if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff; 
          if(diff>deltaPhi)continue;
	  AliStrLine line(gc,gc2,kTRUE);
	  Double_t cp[3];
	  Int_t retcode = line.Cross(&zeta,cp);
	  if(retcode<0)continue;
	  Double_t dca = line.GetDCA(&zeta);
	  if(dca<0.) continue;
	  if(dca>deltaR)continue;
	  Double_t deltaZ=cp[2]-zvert;
	  if(TMath::Abs(deltaZ)>dZmax)continue;
	  MakeTracklet(gc,gc2,nolines);
	}
	detTypeRec.ResetRecPoints();
      }
    }
    delete prpl1;
  }
  if(nolines == 0)return -2;
  return nolines;
}

//______________________________________________________________________
void AliITSVertexer3D::FindVertices(){
  // computes the vertices of the events in the range FirstEvent - LastEvent
  AliRunLoader *rl = AliRunLoader::GetRunLoader();
  AliITSLoader* itsLoader =  (AliITSLoader*) rl->GetLoader("ITSLoader");
  itsLoader->ReloadRecPoints();
  for(Int_t i=fFirstEvent;i<=fLastEvent;i++){
    rl->GetEvent(i);
    FindVertexForCurrentEvent(i);
    if(fCurrentVertex){
      WriteCurrentVertex();
    }
  }
}


//______________________________________________________________________
void AliITSVertexer3D::Find3DVertex(){
  // Determines the vertex position 
  // same algorithm as in AliVertexerTracks::StrLinVertexFinderMinDist(0)
  // adapted to pure AliStrLine objects

  Int_t knacc = fLines->GetEntriesFast();  
  Double_t (*vectP0)[3]=new Double_t [knacc][3];
  Double_t (*vectP1)[3]=new Double_t [knacc][3];
  
  Double_t sum[3][3];
  Double_t dsum[3]={0,0,0};
  for(Int_t i=0;i<3;i++)
    for(Int_t j=0;j<3;j++)sum[i][j]=0;
  for(Int_t i=0; i<knacc; i++){
    AliStrLine *line1 = (AliStrLine*)fLines->At(i); 

    Double_t p0[3],cd[3];
    line1->GetP0(p0);
    line1->GetCd(cd);
    Double_t p1[3]={p0[0]+cd[0],p0[1]+cd[1],p0[2]+cd[2]};
    vectP0[i][0]=p0[0];
    vectP0[i][1]=p0[1];
    vectP0[i][2]=p0[2];
    vectP1[i][0]=p1[0];
    vectP1[i][1]=p1[1];
    vectP1[i][2]=p1[2];
    
    Double_t matr[3][3];
    Double_t dknow[3];
    AliVertexerTracks::GetStrLinDerivMatrix(p0,p1,matr,dknow);

    for(Int_t iii=0;iii<3;iii++){
      dsum[iii]+=dknow[iii]; 
      for(Int_t lj=0;lj<3;lj++) sum[iii][lj]+=matr[iii][lj];
    }
  }
  
  Double_t vett[3][3];
  Double_t det=AliVertexerTracks::GetDeterminant3X3(sum);
  Double_t initPos[3];
  Double_t sigma = 0.;
  for(Int_t i=0;i<3;i++)initPos[i]=0.;

  Int_t goodvert=0;

  if(det!=0){
    for(Int_t zz=0;zz<3;zz++){
      for(Int_t ww=0;ww<3;ww++){
	for(Int_t kk=0;kk<3;kk++) vett[ww][kk]=sum[ww][kk];
      }
      for(Int_t kk=0;kk<3;kk++) vett[kk][zz]=dsum[kk];
      initPos[zz]=AliVertexerTracks::GetDeterminant3X3(vett)/det;
    }

    Double_t rvert=TMath::Sqrt(initPos[0]*initPos[0]+initPos[1]*initPos[1]);
    Double_t zvert=initPos[2];
    if(rvert<fCoarseMaxRCut && TMath::Abs(zvert)<fZCutDiamond){
      for(Int_t i=0; i<knacc; i++){
	Double_t p0[3]={0,0,0},p1[3]={0,0,0};
	for(Int_t ii=0;ii<3;ii++){
	  p0[ii]=vectP0[i][ii];
	  p1[ii]=vectP1[i][ii];
	}
	sigma+=AliVertexerTracks::GetStrLinMinDist(p0,p1,initPos);
      }
      sigma=TMath::Sqrt(sigma);
      goodvert=1;
    }
  }
  delete vectP0;
  delete vectP1;
  if(!goodvert){
    Warning("Find3DVertex","Finder did not succed");
    for(Int_t i=0;i<3;i++)initPos[i]=0.;
    sigma=999;
    knacc=-1;
  }
  if(fVert3D){
    fVert3D-> SetXYZ(initPos);
    fVert3D->SetDispersion(sigma);
    fVert3D->SetNContributors(knacc);
  }else{
    fVert3D = new AliVertex(initPos,sigma,knacc);
  }
  if(fDebug) fVert3D->Print();
}


//______________________________________________________________________
Int_t  AliITSVertexer3D::Prepare3DVertex(Int_t optCuts){
  // Finds the 3D vertex information using tracklets
  Int_t retcode = -1;

  Float_t xbeam=0.;
  Float_t ybeam=0.;
  Float_t zvert=0.;
  Float_t deltaR=fCoarseMaxRCut;
  Float_t dZmax=fZCutDiamond;
  if(optCuts){
    xbeam=fVert3D->GetXv();
    ybeam=fVert3D->GetYv();
    zvert=fVert3D->GetZv();
    deltaR=fMaxRCut;
    dZmax=fMaxZCut;
  }

  Int_t nbr=50;
  Float_t rl=-fCoarseMaxRCut;
  Float_t rh=fCoarseMaxRCut;
  Int_t nbz=100;
  Float_t zl=-fZCutDiamond;
  Float_t zh=fZCutDiamond;
  Float_t binsizer=(rh-rl)/nbr;
  Float_t binsizez=(zh-zl)/nbz;
  TH3F *h3d = new TH3F("h3d","xyz distribution",nbr,rl,rh,nbr,rl,rh,nbz,zl,zh);

 
  // cleanup of the TCLonesArray of tracklets (i.e. fakes are removed)
  Int_t *validate = new Int_t [fLines->GetEntriesFast()];
  for(Int_t i=0; i<fLines->GetEntriesFast();i++)validate[i]=0;
  for(Int_t i=0; i<fLines->GetEntriesFast()-1;i++){
    if(validate[i]==1)continue;
    AliStrLine *l1 = (AliStrLine*)fLines->At(i);
    for(Int_t j=i+1;j<fLines->GetEntriesFast();j++){
      AliStrLine *l2 = (AliStrLine*)fLines->At(j);
      Float_t dca=l1->GetDCA(l2);
      if(dca > fDCAcut || dca<0.00001) continue;
      Double_t point[3];
      Int_t retc = l1->Cross(l2,point);
      if(retc<0)continue;
      Double_t rad=TMath::Sqrt(point[0]*point[0]+point[1]*point[1]);
      if(rad>fCoarseMaxRCut)continue;
      Double_t deltaX=point[0]-xbeam;
      Double_t deltaY=point[1]-ybeam;
      Double_t deltaZ=point[2]-zvert;
      Double_t raddist=TMath::Sqrt(deltaX*deltaX+deltaY*deltaY);
      if(TMath::Abs(deltaZ)>dZmax)continue;
      if(raddist>deltaR)continue;
      validate[i]++;
      validate[j]++;
      h3d->Fill(point[0],point[1],point[2]);
    }
  }


  Int_t numbtracklets=0;
  for(Int_t i=0; i<fLines->GetEntriesFast();i++)if(validate[i]>=1)numbtracklets++;
  if(numbtracklets<2){delete [] validate; delete h3d; return retcode; }

  for(Int_t i=0; i<fLines->GetEntriesFast();i++){
    if(validate[i]<1)fLines->RemoveAt(i);
  }
  fLines->Compress();
  if (fDebug) cout<<"Number of tracklets (after compress) "<<fLines->GetEntriesFast()<<endl;
  delete [] validate;


  // finds peak in histo
  TAxis *xax = h3d->GetXaxis();  
  TAxis *yax = h3d->GetYaxis();
  TAxis *zax = h3d->GetZaxis();
  Double_t peak[3]={0.,0.,0.};
  Float_t contref = 0.;
  for(Int_t i=xax->GetFirst();i<=xax->GetLast();i++){
    Float_t xval = xax->GetBinCenter(i);
    for(Int_t j=yax->GetFirst();j<=yax->GetLast();j++){
      Float_t yval = yax->GetBinCenter(j);
      for(Int_t k=zax->GetFirst();k<=zax->GetLast();k++){
	Float_t bc = h3d->GetBinContent(i,j,k);
	Float_t zval = zax->GetBinCenter(k);
	if(bc>contref){
	  contref = bc;
	  peak[2] = zval;
	  peak[1] = yval;
	  peak[0] = xval;
	}
      }
    }
  }
  delete h3d;

  //         Second selection loop
  Float_t bs=(binsizer+binsizez)/2.;
  for(Int_t i=0; i<fLines->GetEntriesFast();i++){
    AliStrLine *l1 = (AliStrLine*)fLines->At(i);
    if(l1->GetDistFromPoint(peak)>2.5*bs)fLines->RemoveAt(i);
  }
  fLines->Compress();
  if (fDebug) cout<<"Number of tracklets (after 2nd compression) "<<fLines->GetEntriesFast()<<endl;


  if(fLines->GetEntriesFast()>1){
    Find3DVertex();   //  find a first candidate for the primary vertex
    // make a further selection on tracklets based on this first candidate
    fVert3D->GetXYZ(peak);
    if (fDebug) cout<<"FIRSTgv Ma V candidate: "<<peak[0]<<"; "<<peak[1]<<"; "<<peak[2]<<endl;
    for(Int_t i=0; i<fLines->GetEntriesFast();i++){
      AliStrLine *l1 = (AliStrLine*)fLines->At(i);
      if(l1->GetDistFromPoint(peak)> fDCAcut)fLines->RemoveAt(i);
    }
    fLines->Compress();
    if (fDebug) cout<<"Number of tracklets (after 3rd compression) "<<fLines->GetEntriesFast()<<endl;
    if(fLines->GetEntriesFast()>1){
      retcode = 0;   // this last tracklet selection will be used
      delete fVert3D;
      fVert3D = 0;
    }
    else {
	retcode =1; // the previous tracklet selection will be used
    }
  }
  else {
    retcode = 0;
  }
  return retcode;  
}

 //______________________________________________________________________
void  AliITSVertexer3D::MakeTracklet(Double_t *pA, Double_t *pB, Int_t &nolines) {
  // makes a tracklet
  TClonesArray &lines = *fLines;
  if(nolines == 0){
    if(fLines->GetEntriesFast()>0)fLines->Clear();
  }
  if(fLines->GetEntriesFast()==fLines->GetSize()){
    Int_t newsize=(Int_t) 1.5*fLines->GetEntriesFast();
    fLines->Expand(newsize);
  }

  new(lines[nolines++])AliStrLine(pA,pB,kTRUE);
}

 //______________________________________________________________________
void  AliITSVertexer3D::MakeTracklet(Float_t *pA, Float_t *pB, Int_t &nolines) {// Makes a tracklet
  //
  Double_t a[3],b[3];
  for(Int_t i=0;i<3;i++){
    a[i] = pA[i];
    b[i] = pB[i];
  }
  MakeTracklet(a,b,nolines);
}

//________________________________________________________
void AliITSVertexer3D::PrintStatus() const {
  // Print current status
  cout <<"=======================================================\n";
  cout << "Loose cut on Delta Phi "<<fCoarseDiffPhiCut<<endl;
  cout << "Cut on tracklet DCA to Z axis "<<fCoarseMaxRCut<<endl;
  cout << "Cut on tracklet DCA to beam axis "<<fMaxRCut<<endl;
  cout << "Cut on diamond (Z) "<<fZCutDiamond<<endl;
  cout << "Cut on DCA - tracklet to tracklet and to vertex "<<fDCAcut<<endl;
  cout <<" Max Phi difference: "<<fDiffPhiMax<<endl;

 
  cout <<"=======================================================\n";
}
Commit	Line	Data
70c95f95	1	/**************************************************************************
	2	* Copyright(c) 2006-2008, 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	#include <AliESDVertex.h>
	16	#include <AliITSVertexer3D.h>
	17	#include <AliStrLine.h>
	18	#include <AliVertexerTracks.h>
	19	#include <Riostream.h>
	20	#include <TH3F.h>
	21	#include <TTree.h>
	22	#include<TClonesArray.h>
	23	#include "AliRunLoader.h"
	24	#include "AliITSLoader.h"
	25	#include "AliITSgeom.h"
	26	#include "AliITSDetTypeRec.h"
	27	#include "AliITSRecPoint.h"
	28	/////////////////////////////////////////////////////////////////
	29	// this class implements a method to determine
	30	// the 3 coordinates of the primary vertex
	31	// for p-p collisions
	32	// It can be used successfully with Pb-Pb collisions
	33	////////////////////////////////////////////////////////////////
	34
	35	ClassImp(AliITSVertexer3D)
	36
	37	//______________________________________________________________________
	38	AliITSVertexer3D::AliITSVertexer3D():AliITSVertexer(),
	39	fLines(),
	40	fVert3D(),
	41	fCoarseDiffPhiCut(0.),
05d1294c	42	fCoarseMaxRCut(0.),
70c95f95	43	fMaxRCut(0.),
70c95f95	44	fZCutDiamond(0.),
05d1294c	45	fMaxZCut(0.),
70c95f95	46	fDCAcut(0.),
	47	fDiffPhiMax(0.) {
	48	// Default constructor
	49	SetCoarseDiffPhiCut();
05d1294c	50	SetCoarseMaxRCut();
70c95f95	51	SetMaxRCut();
70c95f95	52	SetZCutDiamond();
05d1294c	53	SetMaxZCut();
70c95f95	54	SetDCAcut();
	55	SetDiffPhiMax();
	56
	57	}
	58
	59	//______________________________________________________________________
	60	AliITSVertexer3D::AliITSVertexer3D(TString fn): AliITSVertexer(fn),
	61	fLines(),
	62	fVert3D(),
05d1294c	63	fCoarseDiffPhiCut(0.),
05d1294c	64	fCoarseMaxRCut(0.),
70c95f95	65	fMaxRCut(0.),
70c95f95	66	fZCutDiamond(0.),
05d1294c	67	fMaxZCut(0.),
70c95f95	68	fDCAcut(0.),
	69	fDiffPhiMax(0.) {
	70	// Standard constructor
	71	fLines = new TClonesArray("AliStrLine",1000);
	72	SetCoarseDiffPhiCut();
05d1294c	73	SetCoarseMaxRCut();
70c95f95	74	SetMaxRCut();
70c95f95	75	SetZCutDiamond();
05d1294c	76	SetMaxZCut();
70c95f95	77	SetDCAcut();
	78	SetDiffPhiMax();
	79	}
	80
	81	//______________________________________________________________________
	82	AliITSVertexer3D::~AliITSVertexer3D() {
	83	// Destructor
	84	fVert3D = 0; // this object is not owned by this class
	85	if(fLines){
	86	fLines->Delete();
	87	delete fLines;
	88	}
	89	}
	90
	91	//______________________________________________________________________
	92	AliESDVertex* AliITSVertexer3D::FindVertexForCurrentEvent(Int_t evnumber){
	93	// Defines the AliESDVertex for the current event
	94	if (fDebug) cout<<"\n \n FindVertexForCurrentEvent - 3D - PROCESSING EVENT "<<evnumber<<endl;
	95	fVert3D = 0;
	96	if(fLines)fLines->Clear();
	97
	98	Int_t nolines = FindTracklets(evnumber,0);
	99	fCurrentVertex = 0;
	100	if(nolines<2)return fCurrentVertex;
05d1294c	101	Int_t rc=Prepare3DVertex(0);
70c95f95	102	if(rc==0)Find3DVertex();
	103	if(fVert3D){
	104	if(fLines) fLines->Delete();
	105	nolines = FindTracklets(evnumber,1);
d35ad08f	106	if(nolines>=2){
05d1294c	107	rc=Prepare3DVertex(1);
d35ad08f	108	if(rc==0)Find3DVertex();
d35ad08f	109	}
70c95f95	110	}
	111
	112	if(fVert3D){
	113	fCurrentVertex = new AliESDVertex();
	114	fCurrentVertex->SetTitle("vertexer: 3D");
	115	fCurrentVertex->SetName("Vertex");
	116	fCurrentVertex->SetXv(fVert3D->GetXv());
	117	fCurrentVertex->SetYv(fVert3D->GetYv());
	118	fCurrentVertex->SetZv(fVert3D->GetZv());
	119	fCurrentVertex->SetDispersion(fVert3D->GetDispersion());
	120	fCurrentVertex->SetNContributors(fVert3D->GetNContributors());
	121	}
	122	FindMultiplicity(evnumber);
	123	return fCurrentVertex;
	124	}
	125
	126	//______________________________________________________________________
	127	Int_t AliITSVertexer3D::FindTracklets(Int_t evnumber, Int_t optCuts){
	128	// All the possible combinations between recpoints on layer 1and 2 are
	129	// considered. Straight lines (=tracklets)are formed.
	130	// The tracklets are processed in Prepare3DVertex
	131	AliRunLoader *rl =AliRunLoader::GetRunLoader();
	132	AliITSLoader* itsLoader = (AliITSLoader*)rl->GetLoader("ITSLoader");
	133	AliITSgeom* geom = itsLoader->GetITSgeom();
	134	itsLoader->LoadRecPoints();
	135	rl->GetEvent(evnumber);
	136
	137	AliITSDetTypeRec detTypeRec;
	138
	139	TTree *tR = itsLoader->TreeR();
	140	detTypeRec.SetTreeAddressR(tR);
	141	TClonesArray *itsRec = 0;
	142	// lc and gc are local and global coordinates for layer 1
	143	Float_t lc[3]; for(Int_t ii=0; ii<3; ii++) lc[ii]=0.;
	144	Float_t gc[3]; for(Int_t ii=0; ii<3; ii++) gc[ii]=0.;
	145	// lc2 and gc2 are local and global coordinates for layer 2
	146	Float_t lc2[3]; for(Int_t ii=0; ii<3; ii++) lc2[ii]=0.;
	147	Float_t gc2[3]; for(Int_t ii=0; ii<3; ii++) gc2[ii]=0.;
	148
	149	itsRec = detTypeRec.RecPoints();
	150	TBranch *branch;
	151	branch = tR->GetBranch("ITSRecPoints");
	152
	153	// Set values for cuts
	154	Float_t xbeam=0., ybeam=0.;
05d1294c	155	Float_t zvert=0.;
70c95f95	156	Float_t deltaPhi=fCoarseDiffPhiCut;
05d1294c	157	Float_t deltaR=fCoarseMaxRCut;
05d1294c	158	Float_t dZmax=fZCutDiamond;
70c95f95	159	if(optCuts){
	160	xbeam=fVert3D->GetXv();
	161	ybeam=fVert3D->GetYv();
05d1294c	162	zvert=fVert3D->GetZv();
70c95f95	163	deltaPhi = fDiffPhiMax;
05d1294c	164	deltaR=fMaxRCut;
05d1294c	165	dZmax=fMaxZCut;
70c95f95	166	}
70c95f95	167	Int_t nrpL1 = 0; // number of rec points on layer 1
	168	Int_t nrpL2 = 0; // number of rec points on layer 2
	169
	170	// By default irstL1=0 and lastL1=79
	171	Int_t irstL1 = geom->GetStartDet(0);
	172	Int_t lastL1 = geom->GetModuleIndex(2,1,1)-1;
	173	for(Int_t module= irstL1; module<=lastL1;module++){ // count number of recopints on layer 1
	174	branch->GetEvent(module);
	175	nrpL1+= itsRec->GetEntries();
	176	detTypeRec.ResetRecPoints();
	177	}
	178	//By default irstL2=80 and lastL2=239
	179	Int_t irstL2 = geom->GetModuleIndex(2,1,1);
	180	Int_t lastL2 = geom->GetLastDet(0);
	181	for(Int_t module= irstL2; module<=lastL2;module++){ // count number of recopints on layer 2
	182	branch->GetEvent(module);
	183	nrpL2+= itsRec->GetEntries();
	184	detTypeRec.ResetRecPoints();
	185	}
	186	if(nrpL1 == 0 \|\| nrpL2 == 0){
	187	itsLoader->UnloadRecPoints();
	188	return -1;
	189	}
	190	if(fDebug) printf("RecPoints on Layer 1,2 = %d, %d\n",nrpL1,nrpL2);
	191
	192	Double_t a[3]={xbeam,ybeam,0.};
	193	Double_t b[3]={xbeam,ybeam,10.};
	194	AliStrLine zeta(a,b,kTRUE);
	195
	196	Int_t nolines = 0;
	197	// Loop on modules of layer 1
	198	for(Int_t modul1= irstL1; modul1<=lastL1;modul1++){ // Loop on modules of layer 1
	199	branch->GetEvent(modul1);
	200	Int_t nrecp1 = itsRec->GetEntries();
	201	TClonesArray *prpl1 = new TClonesArray("AliITSRecPoint",nrecp1);
	202	prpl1->SetOwner();
	203	TClonesArray &rpl1 = *prpl1;
	204	for(Int_t j=0;j<nrecp1;j++){
	205	AliITSRecPoint recp = (AliITSRecPoint)itsRec->At(j);
	206	new(rpl1[j])AliITSRecPoint(*recp);
	207	}
	208	detTypeRec.ResetRecPoints();
	209	for(Int_t j=0;j<nrecp1;j++){
	210	AliITSRecPoint recp = (AliITSRecPoint)prpl1->At(j);
	211	// Local coordinates of this recpoint
	212	lc[0]=recp->GetDetLocalX();
	213	lc[2]=recp->GetDetLocalZ();
	214	geom->LtoG(modul1,lc,gc); // global coordinates
	215	Double_t phi1 = TMath::ATan2(gc[1]-ybeam,gc[0]-xbeam);
	216	if(phi1<0)phi1=2*TMath::Pi()+phi1;
	217	for(Int_t modul2= irstL2; modul2<=lastL2;modul2++){
	218	branch->GetEvent(modul2);
	219	Int_t nrecp2 = itsRec->GetEntries();
	220	for(Int_t j2=0;j2<nrecp2;j2++){
	221	recp = (AliITSRecPoint*)itsRec->At(j2);
	222	lc2[0]=recp->GetDetLocalX();
	223	lc2[2]=recp->GetDetLocalZ();
	224	geom->LtoG(modul2,lc2,gc2);
	225	Double_t phi2 = TMath::ATan2(gc2[1]-ybeam,gc2[0]-xbeam);
	226	if(phi2<0)phi2=2*TMath::Pi()+phi2;
	227	Double_t diff = TMath::Abs(phi2-phi1);
	228	if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff;
	229	if(diff>deltaPhi)continue;
	230	AliStrLine line(gc,gc2,kTRUE);
231	Double_t cp[3];
232	Int_t retcode = line.Cross(&zeta,cp);
233	if(retcode<0)continue;
234	Double_t dca = line.GetDCA(&zeta);
235	if(dca<0.) continue;
05d1294c	236	if(dca>deltaR)continue;
	237	Double_t deltaZ=cp[2]-zvert;
	238	if(TMath::Abs(deltaZ)>dZmax)continue;
70c95f95	239	MakeTracklet(gc,gc2,nolines);
	240	}
	241	detTypeRec.ResetRecPoints();
	242	}
	243	}
	244	delete prpl1;
	245	}
	246	if(nolines == 0)return -2;
	247	return nolines;
	248	}
	249
	250	//______________________________________________________________________
	251	void AliITSVertexer3D::FindVertices(){
	252	// computes the vertices of the events in the range FirstEvent - LastEvent
	253	AliRunLoader *rl = AliRunLoader::GetRunLoader();
	254	AliITSLoader* itsLoader = (AliITSLoader*) rl->GetLoader("ITSLoader");
	255	itsLoader->ReloadRecPoints();
	256	for(Int_t i=fFirstEvent;i<=fLastEvent;i++){
	257	rl->GetEvent(i);
	258	FindVertexForCurrentEvent(i);
	259	if(fCurrentVertex){
	260	WriteCurrentVertex();
	261	}
	262	}
	263	}
	264
	265
	266	//______________________________________________________________________
	267	void AliITSVertexer3D::Find3DVertex(){
	268	// Determines the vertex position
	269	// same algorithm as in AliVertexerTracks::StrLinVertexFinderMinDist(0)
	270	// adapted to pure AliStrLine objects
	271
	272	Int_t knacc = fLines->GetEntriesFast();
	273	Double_t (*vectP0)[3]=new Double_t [knacc][3];
	274	Double_t (*vectP1)[3]=new Double_t [knacc][3];
	275
	276	Double_t sum[3][3];
	277	Double_t dsum[3]={0,0,0};
	278	for(Int_t i=0;i<3;i++)
	279	for(Int_t j=0;j<3;j++)sum[i][j]=0;
	280	for(Int_t i=0; i<knacc; i++){
	281	AliStrLine line1 = (AliStrLine)fLines->At(i);
	282
	283	Double_t p0[3],cd[3];
	284	line1->GetP0(p0);
	285	line1->GetCd(cd);
	286	Double_t p1[3]={p0[0]+cd[0],p0[1]+cd[1],p0[2]+cd[2]};
	287	vectP0[i][0]=p0[0];
	288	vectP0[i][1]=p0[1];
	289	vectP0[i][2]=p0[2];
	290	vectP1[i][0]=p1[0];
	291	vectP1[i][1]=p1[1];
	292	vectP1[i][2]=p1[2];
	293
	294	Double_t matr[3][3];
	295	Double_t dknow[3];
	296	AliVertexerTracks::GetStrLinDerivMatrix(p0,p1,matr,dknow);
	297
	298	for(Int_t iii=0;iii<3;iii++){
	299	dsum[iii]+=dknow[iii];
	300	for(Int_t lj=0;lj<3;lj++) sum[iii][lj]+=matr[iii][lj];
	301	}
	302	}
303
304	Double_t vett[3][3];
305	Double_t det=AliVertexerTracks::GetDeterminant3X3(sum);
306	Double_t initPos[3];
307	Double_t sigma = 0.;
308	for(Int_t i=0;i<3;i++)initPos[i]=0.;
309
310	Int_t goodvert=0;
311
312	if(det!=0){
313	for(Int_t zz=0;zz<3;zz++){
314	for(Int_t ww=0;ww<3;ww++){
315	for(Int_t kk=0;kk<3;kk++) vett[ww][kk]=sum[ww][kk];
316	}
317	for(Int_t kk=0;kk<3;kk++) vett[kk][zz]=dsum[kk];
318	initPos[zz]=AliVertexerTracks::GetDeterminant3X3(vett)/det;
319	}
320
321	Double_t rvert=TMath::Sqrt(initPos[0]initPos[0]+initPos[1]initPos[1]);
322	Double_t zvert=initPos[2];
05d1294c	323	if(rvert<fCoarseMaxRCut && TMath::Abs(zvert)<fZCutDiamond){
70c95f95	324	for(Int_t i=0; i<knacc; i++){
	325	Double_t p0[3]={0,0,0},p1[3]={0,0,0};
	326	for(Int_t ii=0;ii<3;ii++){
	327	p0[ii]=vectP0[i][ii];
	328	p1[ii]=vectP1[i][ii];
	329	}
	330	sigma+=AliVertexerTracks::GetStrLinMinDist(p0,p1,initPos);
	331	}
	332	sigma=TMath::Sqrt(sigma);
	333	goodvert=1;
	334	}
	335	}
	336	delete vectP0;
	337	delete vectP1;
	338	if(!goodvert){
	339	Warning("Find3DVertex","Finder did not succed");
	340	for(Int_t i=0;i<3;i++)initPos[i]=0.;
	341	sigma=999;
	342	knacc=-1;
	343	}
	344	if(fVert3D){
	345	fVert3D-> SetXYZ(initPos);
	346	fVert3D->SetDispersion(sigma);
	347	fVert3D->SetNContributors(knacc);
	348	}else{
	349	fVert3D = new AliVertex(initPos,sigma,knacc);
	350	}
	351	if(fDebug) fVert3D->Print();
	352	}
	353
	354
	355
	356	//______________________________________________________________________
05d1294c	357	Int_t AliITSVertexer3D::Prepare3DVertex(Int_t optCuts){
70c95f95	358	// Finds the 3D vertex information using tracklets
	359	Int_t retcode = -1;
	360
05d1294c	361	Float_t xbeam=0.;
	362	Float_t ybeam=0.;
	363	Float_t zvert=0.;
	364	Float_t deltaR=fCoarseMaxRCut;
	365	Float_t dZmax=fZCutDiamond;
	366	if(optCuts){
	367	xbeam=fVert3D->GetXv();
	368	ybeam=fVert3D->GetYv();
	369	zvert=fVert3D->GetZv();
	370	deltaR=fMaxRCut;
	371	dZmax=fMaxZCut;
	372	}
	373
70c95f95	374	Int_t nbr=50;
05d1294c	375	Float_t rl=-fCoarseMaxRCut;
05d1294c	376	Float_t rh=fCoarseMaxRCut;
70c95f95	377	Int_t nbz=100;
	378	Float_t zl=-fZCutDiamond;
	379	Float_t zh=fZCutDiamond;
	380	Float_t binsizer=(rh-rl)/nbr;
	381	Float_t binsizez=(zh-zl)/nbz;
	382	TH3F *h3d = new TH3F("h3d","xyz distribution",nbr,rl,rh,nbr,rl,rh,nbz,zl,zh);
	383
	384
	385	// cleanup of the TCLonesArray of tracklets (i.e. fakes are removed)
	386	Int_t *validate = new Int_t [fLines->GetEntriesFast()];
	387	for(Int_t i=0; i<fLines->GetEntriesFast();i++)validate[i]=0;
70c95f95	388	for(Int_t i=0; i<fLines->GetEntriesFast()-1;i++){
05d1294c	389	if(validate[i]==1)continue;
70c95f95	390	AliStrLine l1 = (AliStrLine)fLines->At(i);
	391	for(Int_t j=i+1;j<fLines->GetEntriesFast();j++){
	392	AliStrLine l2 = (AliStrLine)fLines->At(j);
05d1294c	393	Float_t dca=l1->GetDCA(l2);
05d1294c	394	if(dca > fDCAcut \|\| dca<0.00001) continue;
70c95f95	395	Double_t point[3];
	396	Int_t retc = l1->Cross(l2,point);
	397	if(retc<0)continue;
	398	Double_t rad=TMath::Sqrt(point[0]point[0]+point[1]point[1]);
05d1294c	399	if(rad>fCoarseMaxRCut)continue;
	400	Double_t deltaX=point[0]-xbeam;
	401	Double_t deltaY=point[1]-ybeam;
	402	Double_t deltaZ=point[2]-zvert;
	403	Double_t raddist=TMath::Sqrt(deltaXdeltaX+deltaYdeltaY);
	404	if(TMath::Abs(deltaZ)>dZmax)continue;
	405	if(raddist>deltaR)continue;
70c95f95	406	validate[i]++;
	407	validate[j]++;
	408	h3d->Fill(point[0],point[1],point[2]);
	409	}
	410	}
	411
	412
	413
70c95f95	414	Int_t numbtracklets=0;
	415	for(Int_t i=0; i<fLines->GetEntriesFast();i++)if(validate[i]>=1)numbtracklets++;
	416	if(numbtracklets<2){delete [] validate; delete h3d; return retcode; }
	417
	418	for(Int_t i=0; i<fLines->GetEntriesFast();i++){
	419	if(validate[i]<1)fLines->RemoveAt(i);
	420	}
	421	fLines->Compress();
	422	if (fDebug) cout<<"Number of tracklets (after compress) "<<fLines->GetEntriesFast()<<endl;
	423	delete [] validate;
	424
05d1294c	425
05d1294c	426	// finds peak in histo
70c95f95	427	TAxis *xax = h3d->GetXaxis();
	428	TAxis *yax = h3d->GetYaxis();
	429	TAxis *zax = h3d->GetZaxis();
70c95f95	430	Double_t peak[3]={0.,0.,0.};
	431	Float_t contref = 0.;
	432	for(Int_t i=xax->GetFirst();i<=xax->GetLast();i++){
	433	Float_t xval = xax->GetBinCenter(i);
	434	for(Int_t j=yax->GetFirst();j<=yax->GetLast();j++){
	435	Float_t yval = yax->GetBinCenter(j);
	436	for(Int_t k=zax->GetFirst();k<=zax->GetLast();k++){
	437	Float_t bc = h3d->GetBinContent(i,j,k);
	438	Float_t zval = zax->GetBinCenter(k);
	439	if(bc>contref){
	440	contref = bc;
	441	peak[2] = zval;
	442	peak[1] = yval;
	443	peak[0] = xval;
	444	}
	445	}
	446	}
	447	}
	448	delete h3d;
	449
	450	// Second selection loop
	451	Float_t bs=(binsizer+binsizez)/2.;
05d1294c	452	for(Int_t i=0; i<fLines->GetEntriesFast();i++){
70c95f95	453	AliStrLine l1 = (AliStrLine)fLines->At(i);
	454	if(l1->GetDistFromPoint(peak)>2.5*bs)fLines->RemoveAt(i);
	455	}
	456	fLines->Compress();
	457	if (fDebug) cout<<"Number of tracklets (after 2nd compression) "<<fLines->GetEntriesFast()<<endl;
	458
	459
	460	if(fLines->GetEntriesFast()>1){
	461	Find3DVertex(); // find a first candidate for the primary vertex
	462	// make a further selection on tracklets based on this first candidate
	463	fVert3D->GetXYZ(peak);
05d1294c	464	if (fDebug) cout<<"FIRSTgv Ma V candidate: "<<peak[0]<<"; "<<peak[1]<<"; "<<peak[2]<<endl;
05d1294c	465	for(Int_t i=0; i<fLines->GetEntriesFast();i++){
70c95f95	466	AliStrLine l1 = (AliStrLine)fLines->At(i);
	467	if(l1->GetDistFromPoint(peak)> fDCAcut)fLines->RemoveAt(i);
	468	}
	469	fLines->Compress();
	470	if (fDebug) cout<<"Number of tracklets (after 3rd compression) "<<fLines->GetEntriesFast()<<endl;
	471	if(fLines->GetEntriesFast()>1){
	472	retcode = 0; // this last tracklet selection will be used
	473	delete fVert3D;
	474	fVert3D = 0;
	475	}
	476	else {
	477	retcode =1; // the previous tracklet selection will be used
	478	}
	479	}
	480	else {
	481	retcode = 0;
	482	}
	483	return retcode;
	484	}
	485
	486	//______________________________________________________________________
	487	void AliITSVertexer3D::MakeTracklet(Double_t pA, Double_t pB, Int_t &nolines) {
	488	// makes a tracklet
	489	TClonesArray &lines = *fLines;
	490	if(nolines == 0){
	491	if(fLines->GetEntriesFast()>0)fLines->Clear();
	492	}
	493	if(fLines->GetEntriesFast()==fLines->GetSize()){
	494	Int_t newsize=(Int_t) 1.5*fLines->GetEntriesFast();
	495	fLines->Expand(newsize);
	496	}
	497
	498	new(lines[nolines++])AliStrLine(pA,pB,kTRUE);
	499	}
	500
	501	//______________________________________________________________________
	502	void AliITSVertexer3D::MakeTracklet(Float_t pA, Float_t pB, Int_t &nolines) {// Makes a tracklet
	503	//
	504	Double_t a[3],b[3];
	505	for(Int_t i=0;i<3;i++){
	506	a[i] = pA[i];
	507	b[i] = pB[i];
	508	}
	509	MakeTracklet(a,b,nolines);
	510	}
	511
	512	//________________________________________________________
	513	void AliITSVertexer3D::PrintStatus() const {
	514	// Print current status
	515	cout <<"=======================================================\n";
	516	cout << "Loose cut on Delta Phi "<<fCoarseDiffPhiCut<<endl;
05d1294c	517	cout << "Cut on tracklet DCA to Z axis "<<fCoarseMaxRCut<<endl;
05d1294c	518	cout << "Cut on tracklet DCA to beam axis "<<fMaxRCut<<endl;
70c95f95	519	cout << "Cut on diamond (Z) "<<fZCutDiamond<<endl;
	520	cout << "Cut on DCA - tracklet to tracklet and to vertex "<<fDCAcut<<endl;
	521	cout <<" Max Phi difference: "<<fDiffPhiMax<<endl;
	522
	523
	524	cout <<"=======================================================\n";
	525	}