[u/mrichter/AliRoot.git] / HLT / ITS / AliHLTITSVertexerZ.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, 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 "AliHLTITSVertexerZ.h"
#include<TString.h>
#include<TH1.h>
#include<TMath.h>
#include <AliRun.h>
#include <AliITS.h>
#include "AliITSLoader.h"
#include <AliITSgeom.h>
#include <AliITSRecPoint.h>
#include <AliITSclusterV2.h>

//-------------------------------------------------------------------------
//                Implementation of the HLT ITS vertexer class
//
//          Origin: Cvetan Cheshkov, CERN, Cvetan.Cheshkov@cern.ch
//-------------------------------------------------------------------------

ClassImp(AliHLTITSVertexerZ)

AliHLTITSVertexerZ::AliHLTITSVertexerZ():
  AliITSVertexerZ(),
  fZCombf(0),
  fStepFine(0)
{
  // Constructor in case that there is no runloader
  SetBinWidthFine();
}

AliHLTITSVertexerZ::AliHLTITSVertexerZ(TString filename,Float_t x0, Float_t y0):
  AliITSVertexerZ(filename,x0,y0),
  fZCombf(0),
  fStepFine(0)
{
  // Standard Constructor
  SetBinWidthFine();
}

AliHLTITSVertexerZ::~AliHLTITSVertexerZ()
{
  // Destructor
  if (fZCombf) delete fZCombf;
}

//______________________________________________________________________
AliHLTITSVertexerZ::AliHLTITSVertexerZ(const AliHLTITSVertexerZ &vtxr) :
  AliITSVertexerZ(vtxr),
  fZCombf(vtxr.fZCombf),
  fStepFine(vtxr.fStepFine)
{
  // Copy constructor

}

//______________________________________________________________________
AliHLTITSVertexerZ& AliHLTITSVertexerZ::operator=(const AliHLTITSVertexerZ&  vtxr )
{
  // Assignment operator
  this->~AliHLTITSVertexerZ();
  new(this) AliHLTITSVertexerZ(vtxr);
  fZCombf = vtxr.fZCombf;
  fStepFine = vtxr.fStepFine;

  return *this;
}
//______________________________________________________________________
AliESDVertex* AliHLTITSVertexerZ::FindVertexForCurrentEvent(Int_t evnumber){
  // Defines the AliESDVertex for the current event

  fCurrentVertex = 0;
  AliRunLoader *rl =AliRunLoader::GetRunLoader();
  AliITSLoader* itsLoader =  (AliITSLoader*) rl->GetLoader("ITSLoader");
  itsLoader->LoadRecPoints();
  rl->GetEvent(evnumber);

  /*  if(!fITS)  {
    fITS = (AliITS*)gAlice->GetModule("ITS");
    if(!fITS) {
      Error("FindVertexForCurrentEvent","AliITS object was not found");
      return fCurrentVertex;
    }
  }
  */

  // fITS->SetTreeAddress();
  rl->CdGAFile();

  AliITSgeom* geom=itsLoader->GetITSgeom();
  TTree *tR = itsLoader->TreeR();
  
  return FindVertexForCurrentEvent(geom,tR);
}

//______________________________________________________________________
AliESDVertex* AliHLTITSVertexerZ::FindVertexForCurrentEvent(AliITSgeom *geom,TTree *tR){
  // Defines the AliESDVertex for the current event

  fCurrentVertex = 0;

  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.;
  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.;

  TClonesArray dummy("AliITSclusterV2",10000), *clusters=&dummy;
  TBranch *branch;
  branch = tR->GetBranch("Clusters");
  branch->SetAddress(&clusters);

  Int_t nrpL1 = 0;
  Int_t nrpL2 = 0;
  for(Int_t module= fFirstL1; module<=fLastL1;module++){
    if(module%4==0 || module%4==3)continue;
    //   cout<<"Procesing module "<<module<<" ";
    tR->GetEvent(module);
    //    cout<<"Number of clusters "<<clusters->GetEntries()<<endl;
    nrpL1+= clusters->GetEntriesFast();
  }
  for(Int_t module= fFirstL2; module<=fLastL2;module++){
    tR->GetEvent(module);
    nrpL2+= clusters->GetEntriesFast();
  }
  if(nrpL1 == 0 || nrpL2 == 0){
    ResetHistograms();
    return fCurrentVertex;
  }

  Int_t nPhiBins = (Int_t)(TMath::Pi()/fDiffPhiMax);
  Float_t phiBinSize = 2*TMath::Pi()/(Float_t)nPhiBins;

  Int_t maxind1 = 2*nrpL1/nPhiBins;
  Float_t **zc1 = new Float_t *[nPhiBins];
  Float_t **phi1 = new Float_t *[nPhiBins];
  Float_t **r1 = new Float_t *[nPhiBins];
  Int_t *ind1 = new Int_t [nPhiBins];
  Int_t maxind2 = 2*nrpL2/nPhiBins;
  Float_t **zc2 = new Float_t *[nPhiBins];
  Float_t **phi2 = new Float_t *[nPhiBins];
  Float_t **r2 = new Float_t *[nPhiBins];
  Int_t *ind2 = new Int_t [nPhiBins];
  for(Int_t i=0;i<nPhiBins;i++) {
    zc1[i] = new Float_t [maxind1];
    phi1[i] = new Float_t [maxind1];
    r1[i] = new Float_t [maxind1];
    zc2[i] = new Float_t [maxind2];
    phi2[i] = new Float_t [maxind2];
    r2[i] = new Float_t [maxind2];
  }
  
  Float_t yshift = 0;
  Float_t zshift[4] = {-10.708000, -3.536000, 3.536000, 10.708000};

  yshift = 0.248499;
  memset(ind1,0,nPhiBins*sizeof(Int_t));
  for(Int_t module= fFirstL1; module<=fLastL1;module++){
    if(module%4==0 || module%4==3)continue;
    tR->GetEvent(module);
    Int_t nrecp1 = clusters->GetEntriesFast();
    for(Int_t j=0;j<nrecp1;j++){
      AliITSclusterV2 *recp = (AliITSclusterV2*)clusters->UncheckedAt(j);
      lc[0]=-recp->GetY()+yshift;
      lc[2]=-recp->GetZ()+zshift[module%4];
      geom->LtoG(module,lc,gc);
      gc[0]-=fX0;
      gc[1]-=fY0;
      Float_t xc1,yc1;
      xc1=gc[0];
      yc1=gc[1];
      Float_t phi = TMath::ATan2(gc[1],gc[0]);
      if(phi<0)phi=2*TMath::Pi()+phi;
      Int_t bin = (Int_t)(phi/phiBinSize);
      if(bin>=nPhiBins || bin<0) bin = 0;
      Int_t ind = ind1[bin];
      if(ind<maxind1) {
	phi1[bin][ind] = phi;
	zc1[bin][ind]=gc[2]/fStepFine;
	r1[bin][ind]=sqrt(xc1*xc1+yc1*yc1);
	ind1[bin]++;
      }
    }
    clusters->Delete();
  }
  yshift = 3.096207;
  memset(ind2,0,nPhiBins*sizeof(Int_t));
  for(Int_t module= fFirstL2; module<=fLastL2;module++){
    tR->GetEvent(module);
    Int_t nrecp2 = clusters->GetEntriesFast();
    for(Int_t j=0;j<nrecp2;j++){
      AliITSclusterV2 *recp = (AliITSclusterV2*)clusters->UncheckedAt(j);
      lc[0]=recp->GetY()+yshift;
      lc[2]=-recp->GetZ()+zshift[module%4];
      geom->LtoG(module,lc,gc);
      gc[0]-=fX0;
      gc[1]-=fY0;
      Float_t xc2,yc2;
      xc2=gc[0];
      yc2=gc[1];
      Float_t phi = TMath::ATan2(gc[1],gc[0]);
      if(phi<0)phi=2*TMath::Pi()+phi;
      Int_t bin = (Int_t)(phi/phiBinSize+0.5);
      if(bin>=nPhiBins || bin<0) bin = 0;
      Int_t ind = ind2[bin];
      if(ind<maxind2) {
	phi2[bin][ind] = phi;
	zc2[bin][ind]=gc[2]/fStepFine;
	r2[bin][ind]=sqrt(xc2*xc2+yc2*yc2);
	ind2[bin]++;
      }
    }
    clusters->Delete();
  }
  Int_t nbinfine = static_cast<Int_t>((fHighLim-fLowLim)/fStepFine);
  Float_t lowz = fLowLim/fStepFine;
  Int_t *harray = new Int_t[nbinfine];
  memset(harray,0,nbinfine*sizeof(Int_t));
  for(Int_t ibin=0;ibin<nPhiBins;ibin++) {
    Float_t *pphi1 = phi1[ibin];
    Float_t *pr1 = r1[ibin];
    Float_t *pzc1 = zc1[ibin];
    for(Int_t i=0;i<ind1[ibin];i++){
      for(Int_t jbin=ibin;jbin<=(ibin+1);jbin++) {
	Int_t jbin2 = jbin;
	if(jbin==nPhiBins) jbin2 = 0;
	Float_t *pphi2 = phi2[jbin2];
	Float_t *pr2 = r2[jbin2];
	Float_t *pzc2 = zc2[jbin2];
	for(Int_t j=0;j<ind2[jbin2];j++){
	  Float_t diff = TMath::Abs(pphi2[j]-pphi1[i]);
	  if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff;
	  if(diff<fDiffPhiMax){
	    Float_t zr0=(pr2[j]*pzc1[i]-pr1[i]*pzc2[j])/(pr2[j]-pr1[i]);
	    Int_t bin = (Int_t)(zr0-lowz);
	    if(bin>=0 && bin<nbinfine){
	      harray[bin]++;
	    }
	  }
	}
      }
    }
  }
  for(Int_t i=0;i<nPhiBins;i++) {
    delete [] zc1[i];
    delete [] phi1[i];
    delete [] r1[i];
    delete [] zc2[i];
    delete [] phi2[i];
    delete [] r2[i];
  }
  delete [] zc1;
  delete [] phi1;
  delete [] r1;
  delete [] ind1;
  delete [] zc2;
  delete [] phi2;
  delete [] r2;
  delete [] ind2;

  Int_t nbinratio = (Int_t)(fStepCoarse/fStepFine+0.5);
  Int_t nbincoarse = nbinfine/nbinratio;

  if(fZCombc)delete fZCombc;
  fZCombc = new TH1F("fZCombc","Z",nbincoarse,fLowLim,fLowLim+nbincoarse*fStepCoarse);
  if(fZCombf)delete fZCombf;
  fZCombf = new TH1F("fZCombf","Z",nbinfine,fLowLim,fLowLim+nbinfine*fStepFine);
  Stat_t contents=0;
  Int_t counter=0;
  for(Int_t bin=0;bin<nbinfine;bin++) {
    fZCombf->SetBinContent(bin+1,(Stat_t)harray[bin]);
    fZCombf->SetBinError(bin+1,TMath::Sqrt((Stat_t)harray[bin]));
    contents+=(Stat_t)harray[bin];
    counter++;
    if(counter==nbinratio) {
      Int_t binc=bin/nbinratio; 
      fZCombc->SetBinContent(binc+1,contents);
      fZCombc->SetBinError(binc+1,TMath::Sqrt(contents));
      contents=0;
      counter=0;
    }
  }

  delete [] harray;

  if(fZCombc->GetEntries()==0){
    Warning("FindVertexForCurrentEvent","Insufficient number of rec. points\n");
    ResetHistograms();
    return fCurrentVertex;
  }
  //  else {
  //    cout<<"Number of entries in hist. "<<fZCombc->GetEntries()<<endl;
  //  }
  Int_t bi = fZCombc->GetMaximumBin();
  Float_t centre = fZCombc->GetBinCenter(bi);
  Int_t n1 = static_cast<Int_t>((centre-fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
  Int_t n2 = static_cast<Int_t>((centre+fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
  Int_t niter = 0;
  Bool_t goon = kTRUE;
  Int_t num;
  while(goon){
    fZFound = 0.;
    fZsig = 0.;
    num=0;
    for(Int_t n=n1;n<=n2;n++){
      fZFound+=fZCombf->GetBinCenter(n)*fZCombf->GetBinContent(n);
      num+=static_cast<Int_t>(fZCombf->GetBinContent(n));
      fZsig+=fZCombf->GetBinCenter(n)*fZCombf->GetBinCenter(n)*fZCombf->GetBinContent(n);
    }
    if(num<2){
      fZsig = 0.;
    }
    else {
      Float_t radi =  fZsig/(num-1)-fZFound*fZFound/num/(num-1);
      if(radi>0.)fZsig=TMath::Sqrt(radi);
      else fZsig=0.;
      fZFound/=num;
    }
    goon = TMath::Abs(TMath::Abs(fZFound-fZCombf->GetBinCenter(n1))-TMath::Abs(fZFound-fZCombf->GetBinCenter(n2)))>fTolerance;
    n1 = static_cast<Int_t>((fZFound-fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
    n2 = static_cast<Int_t>((fZFound+fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
    niter++;
    if(niter>=10){
      goon = kFALSE;
      Warning("FindVertexForCurrentEvent","The procedure dows not converge\n");
    }
  }
  //  cout<<"Numer of Iterations "<<niter<<endl<<endl;
  fCurrentVertex = new AliESDVertex(fZFound,fZsig,num);
  fCurrentVertex->SetTitle("vertexer: HLT");
  ResetHistograms();
  PrintStatus();
  return fCurrentVertex;
}
Commit	Line	Data
dd36288a	1	/**************************************************************************
	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
4aa41877	15	#include "AliHLTITSVertexerZ.h"
dd36288a	16	#include<TString.h>
	17	#include<TH1.h>
	18	#include<TMath.h>
	19	#include <AliRun.h>
	20	#include <AliITS.h>
	21	#include "AliITSLoader.h"
	22	#include <AliITSgeom.h>
	23	#include <AliITSRecPoint.h>
3136129d	24	#include <AliITSclusterV2.h>
dd36288a	25
	26	//-------------------------------------------------------------------------
	27	// Implementation of the HLT ITS vertexer class
	28	//
	29	// Origin: Cvetan Cheshkov, CERN, Cvetan.Cheshkov@cern.ch
	30	//-------------------------------------------------------------------------
	31
4aa41877	32	ClassImp(AliHLTITSVertexerZ)
dd36288a	33
8b40a6b8	34	AliHLTITSVertexerZ::AliHLTITSVertexerZ():
	35	AliITSVertexerZ(),
	36	fZCombf(0),
	37	fStepFine(0)
	38	{
3136129d	39	// Constructor in case that there is no runloader
3136129d	40	SetBinWidthFine();
3136129d	41	}
3136129d	42
8b40a6b8	43	AliHLTITSVertexerZ::AliHLTITSVertexerZ(TString filename,Float_t x0, Float_t y0):
	44	AliITSVertexerZ(filename,x0,y0),
	45	fZCombf(0),
	46	fStepFine(0)
dd36288a	47	{
dd36288a	48	// Standard Constructor
8b40a6b8	49	SetBinWidthFine();
	50	}
	51
	52	AliHLTITSVertexerZ::~AliHLTITSVertexerZ()
	53	{
	54	// Destructor
	55	if (fZCombf) delete fZCombf;
dd36288a	56	}
dd36288a	57
8b40a6b8	58	//______________________________________________________________________
	59	AliHLTITSVertexerZ::AliHLTITSVertexerZ(const AliHLTITSVertexerZ &vtxr) :
	60	AliITSVertexerZ(vtxr),
	61	fZCombf(vtxr.fZCombf),
	62	fStepFine(vtxr.fStepFine)
	63	{
	64	// Copy constructor
	65
	66	}
	67
	68	//______________________________________________________________________
	69	AliHLTITSVertexerZ& AliHLTITSVertexerZ::operator=(const AliHLTITSVertexerZ& vtxr )
	70	{
	71	// Assignment operator
	72	this->~AliHLTITSVertexerZ();
	73	new(this) AliHLTITSVertexerZ(vtxr);
	74	fZCombf = vtxr.fZCombf;
	75	fStepFine = vtxr.fStepFine;
	76
	77	return *this;
	78	}
dd36288a	79	//______________________________________________________________________
4aa41877	80	AliESDVertex* AliHLTITSVertexerZ::FindVertexForCurrentEvent(Int_t evnumber){
dd36288a	81	// Defines the AliESDVertex for the current event
	82
	83	fCurrentVertex = 0;
	84	AliRunLoader *rl =AliRunLoader::GetRunLoader();
	85	AliITSLoader* itsLoader = (AliITSLoader*) rl->GetLoader("ITSLoader");
	86	itsLoader->LoadRecPoints();
	87	rl->GetEvent(evnumber);
	88
7d62fb64	89	/* if(!fITS) {
dd36288a	90	fITS = (AliITS*)gAlice->GetModule("ITS");
	91	if(!fITS) {
	92	Error("FindVertexForCurrentEvent","AliITS object was not found");
	93	return fCurrentVertex;
	94	}
	95	}
7d62fb64	96	*/
dd36288a	97
7d62fb64	98	// fITS->SetTreeAddress();
7d62fb64	99	rl->CdGAFile();
dd36288a	100
61436bc1	101	AliITSgeom* geom=itsLoader->GetITSgeom();
dd36288a	102	TTree *tR = itsLoader->TreeR();
7d62fb64	103
3136129d	104	return FindVertexForCurrentEvent(geom,tR);
	105	}
	106
	107	//______________________________________________________________________
4aa41877	108	AliESDVertex* AliHLTITSVertexerZ::FindVertexForCurrentEvent(AliITSgeom geom,TTree tR){
3136129d	109	// Defines the AliESDVertex for the current event
	110
	111	fCurrentVertex = 0;
	112
dd36288a	113	Float_t lc[3]; for(Int_t ii=0; ii<3; ii++) lc[ii]=0.;
	114	Float_t gc[3]; for(Int_t ii=0; ii<3; ii++) gc[ii]=0.;
	115	Float_t lc2[3]; for(Int_t ii=0; ii<3; ii++) lc2[ii]=0.;
	116	Float_t gc2[3]; for(Int_t ii=0; ii<3; ii++) gc2[ii]=0.;
	117
dd36288a	118	TClonesArray dummy("AliITSclusterV2",10000), *clusters=&dummy;
dd36288a	119	TBranch *branch;
3136129d	120	branch = tR->GetBranch("Clusters");
3136129d	121	branch->SetAddress(&clusters);
dd36288a	122
	123	Int_t nrpL1 = 0;
	124	Int_t nrpL2 = 0;
	125	for(Int_t module= fFirstL1; module<=fLastL1;module++){
	126	if(module%4==0 \|\| module%4==3)continue;
	127	// cout<<"Procesing module "<<module<<" ";
3136129d	128	tR->GetEvent(module);
dd36288a	129	// cout<<"Number of clusters "<<clusters->GetEntries()<<endl;
3136129d	130	nrpL1+= clusters->GetEntriesFast();
dd36288a	131	}
dd36288a	132	for(Int_t module= fFirstL2; module<=fLastL2;module++){
3136129d	133	tR->GetEvent(module);
3136129d	134	nrpL2+= clusters->GetEntriesFast();
dd36288a	135	}
	136	if(nrpL1 == 0 \|\| nrpL2 == 0){
	137	ResetHistograms();
	138	return fCurrentVertex;
	139	}
	140
	141	Int_t nPhiBins = (Int_t)(TMath::Pi()/fDiffPhiMax);
	142	Float_t phiBinSize = 2*TMath::Pi()/(Float_t)nPhiBins;
	143
	144	Int_t maxind1 = 2*nrpL1/nPhiBins;
	145	Float_t *zc1 = new Float_t [nPhiBins];
	146	Float_t *phi1 = new Float_t [nPhiBins];
	147	Float_t *r1 = new Float_t [nPhiBins];
	148	Int_t *ind1 = new Int_t [nPhiBins];
	149	Int_t maxind2 = 2*nrpL2/nPhiBins;
	150	Float_t *zc2 = new Float_t [nPhiBins];
	151	Float_t *phi2 = new Float_t [nPhiBins];
	152	Float_t *r2 = new Float_t [nPhiBins];
	153	Int_t *ind2 = new Int_t [nPhiBins];
	154	for(Int_t i=0;i<nPhiBins;i++) {
	155	zc1[i] = new Float_t [maxind1];
	156	phi1[i] = new Float_t [maxind1];
	157	r1[i] = new Float_t [maxind1];
	158	zc2[i] = new Float_t [maxind2];
	159	phi2[i] = new Float_t [maxind2];
	160	r2[i] = new Float_t [maxind2];
	161	}
3136129d	162
	163	Float_t yshift = 0;
	164	Float_t zshift[4] = {-10.708000, -3.536000, 3.536000, 10.708000};
dd36288a	165
3136129d	166	yshift = 0.248499;
dd36288a	167	memset(ind1,0,nPhiBins*sizeof(Int_t));
	168	for(Int_t module= fFirstL1; module<=fLastL1;module++){
	169	if(module%4==0 \|\| module%4==3)continue;
3136129d	170	tR->GetEvent(module);
3136129d	171	Int_t nrecp1 = clusters->GetEntriesFast();
dd36288a	172	for(Int_t j=0;j<nrecp1;j++){
3136129d	173	AliITSclusterV2 recp = (AliITSclusterV2)clusters->UncheckedAt(j);
	174	lc[0]=-recp->GetY()+yshift;
	175	lc[2]=-recp->GetZ()+zshift[module%4];
dd36288a	176	geom->LtoG(module,lc,gc);
	177	gc[0]-=fX0;
	178	gc[1]-=fY0;
	179	Float_t xc1,yc1;
	180	xc1=gc[0];
	181	yc1=gc[1];
	182	Float_t phi = TMath::ATan2(gc[1],gc[0]);
	183	if(phi<0)phi=2*TMath::Pi()+phi;
	184	Int_t bin = (Int_t)(phi/phiBinSize);
3136129d	185	if(bin>=nPhiBins \|\| bin<0) bin = 0;
dd36288a	186	Int_t ind = ind1[bin];
	187	if(ind<maxind1) {
	188	phi1[bin][ind] = phi;
	189	zc1[bin][ind]=gc[2]/fStepFine;
	190	r1[bin][ind]=sqrt(xc1xc1+yc1yc1);
	191	ind1[bin]++;
	192	}
	193	}
3136129d	194	clusters->Delete();
dd36288a	195	}
3136129d	196	yshift = 3.096207;
dd36288a	197	memset(ind2,0,nPhiBins*sizeof(Int_t));
dd36288a	198	for(Int_t module= fFirstL2; module<=fLastL2;module++){
3136129d	199	tR->GetEvent(module);
3136129d	200	Int_t nrecp2 = clusters->GetEntriesFast();
dd36288a	201	for(Int_t j=0;j<nrecp2;j++){
3136129d	202	AliITSclusterV2 recp = (AliITSclusterV2)clusters->UncheckedAt(j);
	203	lc[0]=recp->GetY()+yshift;
	204	lc[2]=-recp->GetZ()+zshift[module%4];
dd36288a	205	geom->LtoG(module,lc,gc);
	206	gc[0]-=fX0;
	207	gc[1]-=fY0;
	208	Float_t xc2,yc2;
	209	xc2=gc[0];
	210	yc2=gc[1];
	211	Float_t phi = TMath::ATan2(gc[1],gc[0]);
	212	if(phi<0)phi=2*TMath::Pi()+phi;
	213	Int_t bin = (Int_t)(phi/phiBinSize+0.5);
3136129d	214	if(bin>=nPhiBins \|\| bin<0) bin = 0;
dd36288a	215	Int_t ind = ind2[bin];
	216	if(ind<maxind2) {
	217	phi2[bin][ind] = phi;
	218	zc2[bin][ind]=gc[2]/fStepFine;
	219	r2[bin][ind]=sqrt(xc2xc2+yc2yc2);
	220	ind2[bin]++;
	221	}
	222	}
3136129d	223	clusters->Delete();
dd36288a	224	}
	225	Int_t nbinfine = static_cast<Int_t>((fHighLim-fLowLim)/fStepFine);
	226	Float_t lowz = fLowLim/fStepFine;
dd36288a	227	Int_t *harray = new Int_t[nbinfine];
	228	memset(harray,0,nbinfine*sizeof(Int_t));
	229	for(Int_t ibin=0;ibin<nPhiBins;ibin++) {
	230	Float_t *pphi1 = phi1[ibin];
	231	Float_t *pr1 = r1[ibin];
	232	Float_t *pzc1 = zc1[ibin];
	233	for(Int_t i=0;i<ind1[ibin];i++){
	234	for(Int_t jbin=ibin;jbin<=(ibin+1);jbin++) {
	235	Int_t jbin2 = jbin;
	236	if(jbin==nPhiBins) jbin2 = 0;
	237	Float_t *pphi2 = phi2[jbin2];
	238	Float_t *pr2 = r2[jbin2];
	239	Float_t *pzc2 = zc2[jbin2];
	240	for(Int_t j=0;j<ind2[jbin2];j++){
	241	Float_t diff = TMath::Abs(pphi2[j]-pphi1[i]);
	242	if(diff>TMath::Pi())diff=2.*TMath::Pi()-diff;
	243	if(diff<fDiffPhiMax){
	244	Float_t zr0=(pr2[j]pzc1[i]-pr1[i]pzc2[j])/(pr2[j]-pr1[i]);
3136129d	245	Int_t bin = (Int_t)(zr0-lowz);
3136129d	246	if(bin>=0 && bin<nbinfine){
dd36288a	247	harray[bin]++;
	248	}
	249	}
	250	}
	251	}
	252	}
	253	}
	254	for(Int_t i=0;i<nPhiBins;i++) {
	255	delete [] zc1[i];
	256	delete [] phi1[i];
	257	delete [] r1[i];
	258	delete [] zc2[i];
	259	delete [] phi2[i];
	260	delete [] r2[i];
	261	}
	262	delete [] zc1;
	263	delete [] phi1;
	264	delete [] r1;
	265	delete [] ind1;
	266	delete [] zc2;
	267	delete [] phi2;
	268	delete [] r2;
	269	delete [] ind2;
	270
	271	Int_t nbinratio = (Int_t)(fStepCoarse/fStepFine+0.5);
	272	Int_t nbincoarse = nbinfine/nbinratio;
	273
	274	if(fZCombc)delete fZCombc;
	275	fZCombc = new TH1F("fZCombc","Z",nbincoarse,fLowLim,fLowLim+nbincoarse*fStepCoarse);
	276	if(fZCombf)delete fZCombf;
	277	fZCombf = new TH1F("fZCombf","Z",nbinfine,fLowLim,fLowLim+nbinfine*fStepFine);
	278	Stat_t contents=0;
	279	Int_t counter=0;
	280	for(Int_t bin=0;bin<nbinfine;bin++) {
	281	fZCombf->SetBinContent(bin+1,(Stat_t)harray[bin]);
	282	fZCombf->SetBinError(bin+1,TMath::Sqrt((Stat_t)harray[bin]));
	283	contents+=(Stat_t)harray[bin];
	284	counter++;
	285	if(counter==nbinratio) {
	286	Int_t binc=bin/nbinratio;
	287	fZCombc->SetBinContent(binc+1,contents);
	288	fZCombc->SetBinError(binc+1,TMath::Sqrt(contents));
	289	contents=0;
	290	counter=0;
	291	}
	292	}
	293
	294	delete [] harray;
	295
	296	if(fZCombc->GetEntries()==0){
	297	Warning("FindVertexForCurrentEvent","Insufficient number of rec. points\n");
	298	ResetHistograms();
	299	return fCurrentVertex;
	300	}
	301	// else {
	302	// cout<<"Number of entries in hist. "<<fZCombc->GetEntries()<<endl;
	303	// }
	304	Int_t bi = fZCombc->GetMaximumBin();
	305	Float_t centre = fZCombc->GetBinCenter(bi);
	306	Int_t n1 = static_cast<Int_t>((centre-fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
	307	Int_t n2 = static_cast<Int_t>((centre+fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
	308	Int_t niter = 0;
	309	Bool_t goon = kTRUE;
	310	Int_t num;
311	while(goon){
312	fZFound = 0.;
313	fZsig = 0.;
314	num=0;
315	for(Int_t n=n1;n<=n2;n++){
316	fZFound+=fZCombf->GetBinCenter(n)*fZCombf->GetBinContent(n);
317	num+=static_cast<Int_t>(fZCombf->GetBinContent(n));
318	fZsig+=fZCombf->GetBinCenter(n)fZCombf->GetBinCenter(n)fZCombf->GetBinContent(n);
319	}
320	if(num<2){
321	fZsig = 0.;
322	}
323	else {
324	Float_t radi = fZsig/(num-1)-fZFound*fZFound/num/(num-1);
325	if(radi>0.)fZsig=TMath::Sqrt(radi);
326	else fZsig=0.;
327	fZFound/=num;
328	}
329	goon = TMath::Abs(TMath::Abs(fZFound-fZCombf->GetBinCenter(n1))-TMath::Abs(fZFound-fZCombf->GetBinCenter(n2)))>fTolerance;
330	n1 = static_cast<Int_t>((fZFound-fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
331	n2 = static_cast<Int_t>((fZFound+fZCombc->GetBinWidth(bi)-fZCombf->GetBinLowEdge(0))/fZCombf->GetBinWidth(0));
332	niter++;
333	if(niter>=10){
334	goon = kFALSE;
335	Warning("FindVertexForCurrentEvent","The procedure dows not converge\n");
336	}
337	}
338	// cout<<"Numer of Iterations "<<niter<<endl<<endl;
339	fCurrentVertex = new AliESDVertex(fZFound,fZsig,num);
340	fCurrentVertex->SetTitle("vertexer: HLT");
341	ResetHistograms();
342	PrintStatus();
343	return fCurrentVertex;
344	}