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

#include "stdlib.h"
#include <TMath.h>
#include <TRandom.h>
#include <TObjArray.h>
#include <TROOT.h>
#include <TFile.h>
#include <TTree.h>
#include <iostream.h>

#include "AliRun.h"
#include "AliITS.h"
#include "AliITSgeom.h"
#include "AliITSRecPoint.h"
#include "AliGenerator.h"
#include "AliMagF.h"

#include <TH1.h>
#include <TF1.h>
#include <TCanvas.h>
#include <AliITSVertex.h>
#include <TObjArray.h>
#include <TObject.h>


ClassImp(AliITSVertex)

//////////////////////////////////////////////////////////////////////
// AliITSVertex is a class for full 3D primary vertex finding       //
//                                                                  //                                                           //
// Version: 1                                                       //                                   //     
// Written by Giuseppe Lo Re and Francesco Riggi                    //
// Giuseppe.Lore@ct.infn.it                                         //                           //
// Franco.Riggi@ct.infn.it                                          //                           //
// Release date: May 2001                                           //                                                                                           //
//                                                                  //                                                   //
//                                                                  //                                                   //
//////////////////////////////////////////////////////////////////////


//______________________________________________________________________________

AliITSVertex::AliITSVertex() {   

   fPosition = new Double_t[3];
   fResolution = new Double_t[3];
   fSNR = new Double_t[3];
  
   AliITS* aliits =(AliITS *)gAlice->GetDetector("ITS");
   AliITSgeom *g2 = ((AliITS*)aliits)->GetITSgeom(); 
   
   TClonesArray  *recpoints = aliits->RecPoints();
   AliITSRecPoint *pnt;

   Int_t NoPoints1 = 0;                                         
   Int_t NoPoints2 = 0;
   Double_t Vzero[3];
   Double_t AsPar[2];
     
//------------ Rough Vertex evaluation ---------------------------------   

   Int_t i,npoints,ipoint,j,k,max,BinMax;
   Double_t ZCentroid;
   Float_t l[3], p[3];

   Double_t mxpiu = 0;
   Double_t mxmeno = 0;
   Double_t mypiu = 0;
   Double_t mymeno = 0;
   
   TH1F *hITSz1         = new TH1F("hITSz1","",100,-14.35,14.35);
  
   for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++) 
   {
           aliits->ResetRecPoints(); 
       gAlice->TreeR()->GetEvent(i);    
           npoints = recpoints->GetEntries();
           
           for (ipoint=0;ipoint<npoints;ipoint++) {
               pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
               l[0]=pnt->GetX();
               l[1]=0;
               l[2]=pnt->GetZ();
                   g2->LtoG(i, l, p);
                   if(i<80 && TMath::Abs(p[2])<14.35) {         
                        if(p[0]>0) mxpiu++; 
                        if(p[0]<0) mxmeno++; 
                        if(p[1]>0) mypiu++; 
                        if(p[1]<0) mymeno++; 
                   hITSz1->Fill(p[2]);       
               }
                   if(i>=80 && TMath::Abs(p[2])<14.35) NoPoints2++;
       }       
   }  
  
   NoPoints1 = (Int_t)(hITSz1->GetEntries()); 
           
   AsPar[0] = (mxpiu-mxmeno)/(mxpiu+mxmeno);
   AsPar[1] = (mypiu-mymeno)/(mypiu+mymeno); 
   
   Vzero[0] = 5.24441*AsPar[0]; 
   Vzero[1] = 5.24441*AsPar[1]; 

   ZCentroid=  TMath::Abs(hITSz1->GetMean()); 
   Vzero[2] = -5.31040e-02+1.42198*ZCentroid+7.44718e-01*TMath::Power(ZCentroid,2)
                  -5.73426e-01*TMath::Power(ZCentroid,3)+2.01500e-01*TMath::Power(ZCentroid,4)          
              -3.34118e-02*TMath::Power(ZCentroid,5)+2.20816e-03*TMath::Power(ZCentroid,6);
   
   if(hITSz1->GetMean()<0) Vzero[2] = -Vzero[2];
   
   cout << "\nXvzero: " << Vzero[0] << " cm" << "";
   cout << "\nYvzero: " << Vzero[1] << " cm" << "";
   cout << "\nZvzero: " << Vzero[2] << " cm" << "\n";

   delete hITSz1;

   Double_t dphi,r,DeltaZ,a,b;
   Int_t np1=0;
   Int_t np2=0;
   Int_t niter=0;
   
   Double_t DeltaPhiZ = 0.08;
   
   Float_t B[3];
   Float_t origin[3];
   for(Int_t okm=0;okm<3;okm++) origin[okm]=0;
   gAlice->Field()->Field(origin,B);

   DeltaPhiZ = DeltaPhiZ*B[2]/2;
   Double_t DeltaPhiXY = 1.0;   

//   cout << "\nDeltaPhiZ: " << DeltaPhiZ << " deg" << "\n";   
//   cout << "DeltaPhiXY: " << DeltaPhiXY << " deg" << "\n";   
   
   Double_t *Z1, *Z2, *Y1, *Y2, *X1, *X2, *phi1, *phi2, *r1, *r2;
   Z1=new Double_t[NoPoints1];
   Z2=new Double_t[NoPoints2];
   Y1=new Double_t[NoPoints1];
   Y2=new Double_t[NoPoints2];
   X1=new Double_t[NoPoints1];
   X2=new Double_t[NoPoints2];
   phi1=new Double_t[NoPoints1];
   phi2=new Double_t[NoPoints2];
   r1=new Double_t[NoPoints1];
   r2=new Double_t[NoPoints2];
        
   DeltaZ = 4.91617e-01+2.67567e-02*Vzero[2]+1.49626e-02*TMath::Power(Vzero[2],2); 
   Float_t MulFactorZ = 28000./(Float_t)NoPoints1;
   Int_t nbin=(Int_t)((DeltaZ/0.005)/MulFactorZ);
   Int_t nbinxy=250;
   Int_t *VectorBinZ,*VectorBinXY;
   VectorBinZ=new Int_t[nbin];
   VectorBinXY=new Int_t[nbinxy];
   Float_t f1= 0;
   Float_t f2= 0;
   Double_t sigma,MediaFondo;
     
   TH1D *hITSZv         = new TH1D("hITSZv","",nbin,Vzero[2]-DeltaZ,Vzero[2]+DeltaZ);
   TH1D *hITSXv         = new TH1D("hITSXv","",nbinxy,-3,3);
   TH1D *hITSYv         = new TH1D("hITSYv","",nbinxy,-3,3);

//   cout << "DeltaZeta: " << DeltaZ << " cm" << "\n";   
   
   
   start:   

   hITSZv->Add(hITSZv,-1.);
   hITSXv->Add(hITSXv,-1.);
   hITSYv->Add(hITSYv,-1.);

   np1=np2=0;

   
   for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++) 
   {
        aliits->ResetRecPoints(); 
        gAlice->TreeR()->GetEvent(i);
           npoints = recpoints->GetEntries();
           for (ipoint=0;ipoint<npoints;ipoint++) {
               
                    pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
                l[0]=pnt->GetX();
                l[1]=0;
                l[2]=pnt->GetZ();
                g2->LtoG(i, l, p);
              
                        if(i<80 && TMath::Abs(p[2])<14.35) {
                    p[0]=p[0]-Vzero[0];
                    p[1]=p[1]-Vzero[1];
                r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
                        Y1[np1]=p[1];
                        X1[np1]=p[0];
                        Z1[np1]=p[2]; 
                        r1[np1]=r;
                        phi1[np1]=PhiFunc(p);
                        np1++;
                        }

                        if(i>=80 &&  TMath::Abs(p[2])<14.35) { 
                    p[0]=p[0]-Vzero[0];
                    p[1]=p[1]-Vzero[1];
                r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
                        Y2[np2]=p[1];
                        X2[np2]=p[0];
                        Z2[np2]=p[2];
                        r2[np2]=r;
                        phi2[np2]=PhiFunc(p);
                        np2++;
                        }
                        
          }
   }

//------------------ Correlation between rec points ----------------------
    
   cout << "\nNo. of Points on the two pixel layers: "<<np1<<" "<<np2<<endl; 

   for(j=0; j<(np2)-1; j++) {
         for(k=0; k<(np1)-1; k++) { 
                dphi=TMath::Abs(phi1[k]-phi2[j]);
                if(dphi>180) dphi = 360-dphi;
                if(dphi<DeltaPhiZ && TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-Vzero[2])
                         <DeltaZ) hITSZv->Fill(Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1));        
         }
   }
      
   //cout << "\nNumber of used pairs: \n";
   //cout << hITSZv->GetEntries() << '\n' << '\n';      
   a = Vzero[2]-DeltaZ; 
   b = Vzero[2]+DeltaZ; 
   max=(Int_t) hITSZv->GetMaximum();
   BinMax=hITSZv->GetMaximumBin();
   sigma=0;
   for(i=0;i<nbin;i++) VectorBinZ[i]=(Int_t)hITSZv->GetBinContent(i);
   for(i=0;i<10;i++) f1=f1+VectorBinZ[i]/10;
   for(i=nbin-10;i<nbin;i++) f2=f2+VectorBinZ[i]/10;
   MediaFondo=(f1+f2)/2;
   for(i=0;i<nbin;i++) {
	  if(VectorBinZ[i]-MediaFondo>(max-MediaFondo)*0.4 && 
	  VectorBinZ[i]-MediaFondo<(max-MediaFondo)*0.7) {
		 sigma=hITSZv->GetBinCenter(BinMax)-hITSZv->GetBinCenter(i);
		 sigma=TMath::Abs(sigma);
		 if(sigma==0) sigma=0.05;
      }
   }
   
   cout << "f1 " <<f1 <<endl;
   cout << "f2 " <<f2 <<endl;
   cout << "GetMaximumBin " <<hITSZv->GetMaximumBin() <<endl;
   cout << "nbin " <<nbin <<endl;
   cout << "max " << hITSZv->GetBinContent(BinMax)<<endl;
   cout << "sigma " <<sigma <<endl;
   cout << "Fondo " <<   MediaFondo<< endl;
   
   TF1 *fz = new TF1 ("fz","([0]*exp(-0.5*((x-[1])/[2])*((x-[1])/[2])))+[3]",a,b);  
   
   fz->SetParameter(0,max);
   if(niter==0) {Double_t temp = hITSZv->GetBinCenter(BinMax); Vzero[2]=temp;}
   fz->SetParameter(1,Vzero[2]);
   fz->SetParameter(2,sigma); 
   fz->SetParameter(3,MediaFondo);  
   fz->SetParLimits(2,0,999);
   fz->SetParLimits(3,0,999);
   
   hITSZv->Fit("fz","RMEQ0");
     
   fSNR[2] = fz->GetParameter(0)/fz->GetParameter(3);
   if(fSNR[2]<0.) { 
     cout << "\nNegative Signal to noise ratio for z!!!" << endl;
     cout << "The algorithm cannot find the z vertex position." << endl;
     exit(123456789);
   }
   else
   {
     fPosition[2] = fz->GetParameter(1);
     if(fPosition[2]<0) 
       {
         fPosition[2]=fPosition[2]-TMath::Abs(fPosition[2])*1.11/10000;
       }
     else
       {
         fPosition[2]=fPosition[2]+TMath::Abs(fPosition[2])*1.11/10000;
       }
   }
   fResolution[2] = fz->GetParError(1);
   
   
   for(j=0; j<(np2)-1; j++) {
         for(k=0; k<(np1)-1; k++) { 
                dphi=TMath::Abs(phi1[k]-phi2[j]);
                if(dphi>180) dphi = 360-dphi;
                if(dphi>DeltaPhiXY) continue;
            if(TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-fPosition[2])
                <4*fResolution[2]) {
                   hITSXv->Fill(Vzero[0]+(X2[j]-((X2[j]-X1[k])/(Y2[j]-Y1[k]))*Y2[j]));
                   hITSYv->Fill(Vzero[1]+(Y2[j]-((Y2[j]-Y1[k])/(X2[j]-X1[k]))*X2[j]));
            }
         }
   }
   
   TF1 *fx = new TF1
   ("fx","([0]*exp(-0.5*((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[0]-0.5,Vzero[0]+0.5);  

   max=(Int_t) hITSXv->GetMaximum();
   BinMax=hITSXv->GetMaximumBin();
   sigma=0;
   f1=f2=0;
   for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSXv->GetBinContent(i);
   for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
   for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
   MediaFondo=(f1+f2)/2;
   for(i=0;i<nbinxy;i++) {
	  if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 && 
	  VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
		 sigma=hITSXv->GetBinCenter(BinMax)-hITSXv->GetBinCenter(i);
		 sigma=TMath::Abs(sigma);
		 if(sigma==0) sigma=0.05;
      }
   }
   
   /*cout << "f1 " <<f1 <<endl;
   cout << "f2 " <<f2 <<endl;
   cout << "GetMaximumBin " <<hITSXv->GetMaximumBin() <<endl;
   cout << "max " << hITSXv->GetBinContent(BinMax)<<endl;
   cout << "sigma " <<sigma <<endl;
   cout << "Fondo " <<   MediaFondo<< endl;
   cout << "nbinxy " <<nbinxy <<endl;*/
   
   fx->SetParameter(0,max);
   fx->SetParameter(1,Vzero[0]);
   fx->SetParameter(2,sigma); 
   fx->SetParameter(3,MediaFondo);

   hITSXv->Fit("fx","RMEQ0"); 

   fSNR[0] = fx->GetParameter(0)/fx->GetParameter(3);
   if(fSNR[0]<0.) { 
     cout << "\nNegative Signal to noise ratio for x!!!" << endl;
     cout << "The algorithm cannot find the x vertex position." << endl;
     exit(123456789);  
   }
   else
   {
   fPosition[0]=fx->GetParameter(1);
   fResolution[0]=fx->GetParError(1);
   }

   TF1 *fy = new TF1
   ("fy","([0]*exp(-0.5*((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[1]-0.5,Vzero[1]+0.5);  

   max=(Int_t) hITSYv->GetMaximum();
   BinMax=hITSYv->GetMaximumBin();
   sigma=0;
   f1=f2=0;
   for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSYv->GetBinContent(i);
   for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
   for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
   MediaFondo=(f1+f2)/2;
   for(i=0;i<nbinxy;i++) {
	  if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 && 
	  VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
		 sigma=hITSYv->GetBinCenter(BinMax)-hITSYv->GetBinCenter(i);
		 sigma=TMath::Abs(sigma);
		 if(sigma==0) sigma=0.05;
      }
   }
   
   /*cout << "f1 " <<f1 <<endl;
   cout << "f2 " <<f2 <<endl;
   cout << "GetMaximumBin " <<hITSYv->GetMaximumBin() <<endl;
   cout << "max " << hITSYv->GetBinContent(BinMax)<<endl;
   cout << "sigma " <<sigma <<endl;
   cout << "Fondo " <<   MediaFondo<< endl;
   cout << "nbinxy " <<nbinxy <<endl;*/
   
   fy->SetParameter(0,max);
   fy->SetParameter(1,Vzero[1]);
   fy->SetParameter(2,sigma); 
   fy->SetParameter(3,MediaFondo);
   
   hITSYv->Fit("fy","RMEQ0"); 

   fSNR[1] = fy->GetParameter(0)/fy->GetParameter(3);
   if(fSNR[1]<0.) { 
     cout << "\nNegative Signal to noise ratio for y!!!" << endl;
     cout << "The algorithm cannot find the y vertex position." << endl;
     exit(123456789); 
   }
   else
   {
   fPosition[1]=fy->GetParameter(1);
   fResolution[1]=fy->GetParError(1);
   }

   niter++;
   
   Vzero[0] = fPosition[0];
   Vzero[1] = fPosition[1];
   Vzero[2] = fPosition[2];

   if(niter<3) goto start;  // number of iterations
   

   cout<<"Number of iterations: "<<niter<<endl;
 
   delete [] Z1;
   delete [] Z2;
   delete [] Y1;
   delete [] Y2;
   delete [] X1;
   delete [] X2;
   delete [] r1;
   delete [] r2;
   delete [] phi1;
   delete [] phi2;
   delete [] VectorBinZ;
   delete [] VectorBinXY;
   
   delete hITSZv;
   delete hITSXv;
   delete hITSYv;
   
}


//______________________________________________________________________________

AliITSVertex::~AliITSVertex() { 
   delete [] fPosition;
   delete [] fResolution;
   delete [] fSNR;
}

//______________________________________________________________________________

Double_t AliITSVertex::PhiFunc(Float_t p[]) {
         Double_t phi=0;
         if(p[1]>0 && p[0]>0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578);
         if(p[1]>0 && p[0]<0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+180;
         if(p[1]<0 && p[0]<0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+180;
         if(p[1]<0 && p[0]>0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+360;
         return phi;
}

//______________________________________________________________________________
Commit	Line	Data
e5d2304a	1	#include "stdlib.h"
504de69b	2	#include <TMath.h>
	3	#include <TRandom.h>
	4	#include <TObjArray.h>
	5	#include <TROOT.h>
	6	#include <TFile.h>
	7	#include <TTree.h>
	8	#include <iostream.h>
	9
	10	#include "AliRun.h"
	11	#include "AliITS.h"
	12	#include "AliITSgeom.h"
	13	#include "AliITSRecPoint.h"
	14	#include "AliGenerator.h"
	15	#include "AliMagF.h"
	16
	17	#include <TH1.h>
	18	#include <TF1.h>
	19	#include <TCanvas.h>
	20	#include <AliITSVertex.h>
	21	#include <TObjArray.h>
	22	#include <TObject.h>
	23
	24
	25	ClassImp(AliITSVertex)
	26
6b88f180	27	//////////////////////////////////////////////////////////////////////
	28	// AliITSVertex is a class for full 3D primary vertex finding //
	29	// // //
	30	// Version: 1 // //
	31	// Written by Giuseppe Lo Re and Francesco Riggi //
	32	// Giuseppe.Lore@ct.infn.it // //
	33	// Franco.Riggi@ct.infn.it // //
	34	// Release date: May 2001 // //
	35	// // //
	36	// // //
	37	//////////////////////////////////////////////////////////////////////
504de69b	38
	39
	40	//______________________________________________________________________________
	41
	42	AliITSVertex::AliITSVertex() {
	43
	44	fPosition = new Double_t[3];
	45	fResolution = new Double_t[3];
	46	fSNR = new Double_t[3];
	47
	48	AliITS* aliits =(AliITS *)gAlice->GetDetector("ITS");
	49	AliITSgeom g2 = ((AliITS)aliits)->GetITSgeom();
	50
	51	TClonesArray *recpoints = aliits->RecPoints();
	52	AliITSRecPoint *pnt;
504de69b	53
6b88f180	54	Int_t NoPoints1 = 0;
504de69b	55	Int_t NoPoints2 = 0;
	56	Double_t Vzero[3];
	57	Double_t AsPar[2];
	58
6b88f180	59	//------------ Rough Vertex evaluation ---------------------------------
504de69b	60
6b88f180	61	Int_t i,npoints,ipoint,j,k,max,BinMax;
504de69b	62	Double_t ZCentroid;
	63	Float_t l[3], p[3];
	64
6b88f180	65	Double_t mxpiu = 0;
	66	Double_t mxmeno = 0;
	67	Double_t mypiu = 0;
	68	Double_t mymeno = 0;
	69
504de69b	70	TH1F *hITSz1 = new TH1F("hITSz1","",100,-14.35,14.35);
	71
	72	for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++)
	73	{
6b88f180	74	aliits->ResetRecPoints();
	75	gAlice->TreeR()->GetEvent(i);
	76	npoints = recpoints->GetEntries();
	77
	78	for (ipoint=0;ipoint<npoints;ipoint++) {
	79	pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
	80	l[0]=pnt->GetX();
	81	l[1]=0;
	82	l[2]=pnt->GetZ();
	83	g2->LtoG(i, l, p);
	84	if(i<80 && TMath::Abs(p[2])<14.35) {
	85	if(p[0]>0) mxpiu++;
	86	if(p[0]<0) mxmeno++;
	87	if(p[1]>0) mypiu++;
	88	if(p[1]<0) mymeno++;
	89	hITSz1->Fill(p[2]);
	90	}
	91	if(i>=80 && TMath::Abs(p[2])<14.35) NoPoints2++;
504de69b	92	}
	93	}
	94
	95	NoPoints1 = (Int_t)(hITSz1->GetEntries());
6b88f180	96
504de69b	97	AsPar[0] = (mxpiu-mxmeno)/(mxpiu+mxmeno);
	98	AsPar[1] = (mypiu-mymeno)/(mypiu+mymeno);
	99
6b88f180	100	Vzero[0] = 5.24441*AsPar[0];
6b88f180	101	Vzero[1] = 5.24441*AsPar[1];
504de69b	102
	103	ZCentroid= TMath::Abs(hITSz1->GetMean());
	104	Vzero[2] = -5.31040e-02+1.42198ZCentroid+7.44718e-01TMath::Power(ZCentroid,2)
6b88f180	105	-5.73426e-01TMath::Power(ZCentroid,3)+2.01500e-01TMath::Power(ZCentroid,4)
504de69b	106	-3.34118e-02TMath::Power(ZCentroid,5)+2.20816e-03TMath::Power(ZCentroid,6);
	107
	108	if(hITSz1->GetMean()<0) Vzero[2] = -Vzero[2];
	109
504de69b	110	cout << "\nXvzero: " << Vzero[0] << " cm" << "";
	111	cout << "\nYvzero: " << Vzero[1] << " cm" << "";
	112	cout << "\nZvzero: " << Vzero[2] << " cm" << "\n";
	113
504de69b	114	delete hITSz1;
504de69b	115
6b88f180	116	Double_t dphi,r,DeltaZ,a,b;
504de69b	117	Int_t np1=0;
504de69b	118	Int_t np2=0;
6b88f180	119	Int_t niter=0;
	120
	121	Double_t DeltaPhiZ = 0.08;
	122
	123	Float_t B[3];
	124	Float_t origin[3];
	125	for(Int_t okm=0;okm<3;okm++) origin[okm]=0;
	126	gAlice->Field()->Field(origin,B);
504de69b	127
6b88f180	128	DeltaPhiZ = DeltaPhiZ*B[2]/2;
	129	Double_t DeltaPhiXY = 1.0;
	130
	131	// cout << "\nDeltaPhiZ: " << DeltaPhiZ << " deg" << "\n";
	132	// cout << "DeltaPhiXY: " << DeltaPhiXY << " deg" << "\n";
	133
504de69b	134	Double_t Z1, Z2, Y1, Y2, X1, X2, phi1, phi2, r1, r2;
	135	Z1=new Double_t[NoPoints1];
	136	Z2=new Double_t[NoPoints2];
	137	Y1=new Double_t[NoPoints1];
	138	Y2=new Double_t[NoPoints2];
	139	X1=new Double_t[NoPoints1];
	140	X2=new Double_t[NoPoints2];
	141	phi1=new Double_t[NoPoints1];
	142	phi2=new Double_t[NoPoints2];
	143	r1=new Double_t[NoPoints1];
	144	r2=new Double_t[NoPoints2];
6b88f180	145
	146	DeltaZ = 4.91617e-01+2.67567e-02Vzero[2]+1.49626e-02TMath::Power(Vzero[2],2);
	147	Float_t MulFactorZ = 28000./(Float_t)NoPoints1;
	148	Int_t nbin=(Int_t)((DeltaZ/0.005)/MulFactorZ);
	149	Int_t nbinxy=250;
	150	Int_t VectorBinZ,VectorBinXY;
	151	VectorBinZ=new Int_t[nbin];
	152	VectorBinXY=new Int_t[nbinxy];
	153	Float_t f1= 0;
	154	Float_t f2= 0;
	155	Double_t sigma,MediaFondo;
	156
	157	TH1D *hITSZv = new TH1D("hITSZv","",nbin,Vzero[2]-DeltaZ,Vzero[2]+DeltaZ);
	158	TH1D *hITSXv = new TH1D("hITSXv","",nbinxy,-3,3);
	159	TH1D *hITSYv = new TH1D("hITSYv","",nbinxy,-3,3);
504de69b	160
6b88f180	161	// cout << "DeltaZeta: " << DeltaZ << " cm" << "\n";
504de69b	162
6b88f180	163
6b88f180	164	start:
504de69b	165
6b88f180	166	hITSZv->Add(hITSZv,-1.);
	167	hITSXv->Add(hITSXv,-1.);
	168	hITSYv->Add(hITSYv,-1.);
504de69b	169
6b88f180	170	np1=np2=0;
504de69b	171
6b88f180	172
	173
	174	for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++)
	175	{
	176	aliits->ResetRecPoints();
	177	gAlice->TreeR()->GetEvent(i);
	178	npoints = recpoints->GetEntries();
	179	for (ipoint=0;ipoint<npoints;ipoint++) {
	180
	181	pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
	182	l[0]=pnt->GetX();
	183	l[1]=0;
	184	l[2]=pnt->GetZ();
	185	g2->LtoG(i, l, p);
	186
	187	if(i<80 && TMath::Abs(p[2])<14.35) {
	188	p[0]=p[0]-Vzero[0];
	189	p[1]=p[1]-Vzero[1];
	190	r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
	191	Y1[np1]=p[1];
	192	X1[np1]=p[0];
	193	Z1[np1]=p[2];
	194	r1[np1]=r;
	195	phi1[np1]=PhiFunc(p);
	196	np1++;
	197	}
	198
	199	if(i>=80 && TMath::Abs(p[2])<14.35) {
	200	p[0]=p[0]-Vzero[0];
	201	p[1]=p[1]-Vzero[1];
	202	r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
	203	Y2[np2]=p[1];
	204	X2[np2]=p[0];
	205	Z2[np2]=p[2];
	206	r2[np2]=r;
	207	phi2[np2]=PhiFunc(p);
	208	np2++;
	209	}
	210
	211	}
	212	}
504de69b	213
6b88f180	214	//------------------ Correlation between rec points ----------------------
	215
	216	cout << "\nNo. of Points on the two pixel layers: "<<np1<<" "<<np2<<endl;
504de69b	217
504de69b	218	for(j=0; j<(np2)-1; j++) {
6b88f180	219	for(k=0; k<(np1)-1; k++) {
	220	dphi=TMath::Abs(phi1[k]-phi2[j]);
	221	if(dphi>180) dphi = 360-dphi;
	222	if(dphi<DeltaPhiZ && TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-Vzero[2])
	223	<DeltaZ) hITSZv->Fill(Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1));
	224	}
	225	}
	226
	227	//cout << "\nNumber of used pairs: \n";
	228	//cout << hITSZv->GetEntries() << '\n' << '\n';
	229	a = Vzero[2]-DeltaZ;
	230	b = Vzero[2]+DeltaZ;
	231	max=(Int_t) hITSZv->GetMaximum();
	232	BinMax=hITSZv->GetMaximumBin();
	233	sigma=0;
	234	for(i=0;i<nbin;i++) VectorBinZ[i]=(Int_t)hITSZv->GetBinContent(i);
	235	for(i=0;i<10;i++) f1=f1+VectorBinZ[i]/10;
	236	for(i=nbin-10;i<nbin;i++) f2=f2+VectorBinZ[i]/10;
	237	MediaFondo=(f1+f2)/2;
	238	for(i=0;i<nbin;i++) {
	239	if(VectorBinZ[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	240	VectorBinZ[i]-MediaFondo<(max-MediaFondo)*0.7) {
	241	sigma=hITSZv->GetBinCenter(BinMax)-hITSZv->GetBinCenter(i);
	242	sigma=TMath::Abs(sigma);
	243	if(sigma==0) sigma=0.05;
	244	}
504de69b	245	}
504de69b	246
6b88f180	247	cout << "f1 " <<f1 <<endl;
	248	cout << "f2 " <<f2 <<endl;
	249	cout << "GetMaximumBin " <<hITSZv->GetMaximumBin() <<endl;
	250	cout << "nbin " <<nbin <<endl;
	251	cout << "max " << hITSZv->GetBinContent(BinMax)<<endl;
	252	cout << "sigma " <<sigma <<endl;
	253	cout << "Fondo " << MediaFondo<< endl;
504de69b	254
6b88f180	255	TF1 fz = new TF1 ("fz","([0]exp(-0.5((x-[1])/[2])((x-[1])/[2])))+[3]",a,b);
504de69b	256
6b88f180	257	fz->SetParameter(0,max);
	258	if(niter==0) {Double_t temp = hITSZv->GetBinCenter(BinMax); Vzero[2]=temp;}
	259	fz->SetParameter(1,Vzero[2]);
	260	fz->SetParameter(2,sigma);
	261	fz->SetParameter(3,MediaFondo);
	262	fz->SetParLimits(2,0,999);
	263	fz->SetParLimits(3,0,999);
504de69b	264
6b88f180	265	hITSZv->Fit("fz","RMEQ0");
	266
	267	fSNR[2] = fz->GetParameter(0)/fz->GetParameter(3);
	268	if(fSNR[2]<0.) {
	269	cout << "\nNegative Signal to noise ratio for z!!!" << endl;
	270	cout << "The algorithm cannot find the z vertex position." << endl;
	271	exit(123456789);
504de69b	272	}
	273	else
	274	{
6b88f180	275	fPosition[2] = fz->GetParameter(1);
504de69b	276	if(fPosition[2]<0)
	277	{
	278	fPosition[2]=fPosition[2]-TMath::Abs(fPosition[2])*1.11/10000;
	279	}
	280	else
	281	{
	282	fPosition[2]=fPosition[2]+TMath::Abs(fPosition[2])*1.11/10000;
	283	}
	284	}
6b88f180	285	fResolution[2] = fz->GetParError(1);
504de69b	286
6b88f180	287
	288
	289	for(j=0; j<(np2)-1; j++) {
	290	for(k=0; k<(np1)-1; k++) {
	291	dphi=TMath::Abs(phi1[k]-phi2[j]);
	292	if(dphi>180) dphi = 360-dphi;
	293	if(dphi>DeltaPhiXY) continue;
	294	if(TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-fPosition[2])
	295	<4*fResolution[2]) {
	296	hITSXv->Fill(Vzero[0]+(X2[j]-((X2[j]-X1[k])/(Y2[j]-Y1[k]))*Y2[j]));
	297	hITSYv->Fill(Vzero[1]+(Y2[j]-((Y2[j]-Y1[k])/(X2[j]-X1[k]))*X2[j]));
	298	}
	299	}
	300	}
	301
	302	TF1 *fx = new TF1
	303	("fx","([0]exp(-0.5((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[0]-0.5,Vzero[0]+0.5);
	304
	305	max=(Int_t) hITSXv->GetMaximum();
	306	BinMax=hITSXv->GetMaximumBin();
	307	sigma=0;
	308	f1=f2=0;
	309	for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSXv->GetBinContent(i);
	310	for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
	311	for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
	312	MediaFondo=(f1+f2)/2;
	313	for(i=0;i<nbinxy;i++) {
	314	if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	315	VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
	316	sigma=hITSXv->GetBinCenter(BinMax)-hITSXv->GetBinCenter(i);
	317	sigma=TMath::Abs(sigma);
	318	if(sigma==0) sigma=0.05;
	319	}
	320	}
	321
	322	/*cout << "f1 " <<f1 <<endl;
	323	cout << "f2 " <<f2 <<endl;
	324	cout << "GetMaximumBin " <<hITSXv->GetMaximumBin() <<endl;
	325	cout << "max " << hITSXv->GetBinContent(BinMax)<<endl;
	326	cout << "sigma " <<sigma <<endl;
	327	cout << "Fondo " << MediaFondo<< endl;
	328	cout << "nbinxy " <<nbinxy <<endl;*/
	329
	330	fx->SetParameter(0,max);
	331	fx->SetParameter(1,Vzero[0]);
	332	fx->SetParameter(2,sigma);
	333	fx->SetParameter(3,MediaFondo);
	334
	335	hITSXv->Fit("fx","RMEQ0");
	336
	337	fSNR[0] = fx->GetParameter(0)/fx->GetParameter(3);
	338	if(fSNR[0]<0.) {
	339	cout << "\nNegative Signal to noise ratio for x!!!" << endl;
	340	cout << "The algorithm cannot find the x vertex position." << endl;
	341	exit(123456789);
	342	}
	343	else
	344	{
	345	fPosition[0]=fx->GetParameter(1);
	346	fResolution[0]=fx->GetParError(1);
	347	}
504de69b	348
6b88f180	349	TF1 *fy = new TF1
	350	("fy","([0]exp(-0.5((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[1]-0.5,Vzero[1]+0.5);
	351
	352	max=(Int_t) hITSYv->GetMaximum();
	353	BinMax=hITSYv->GetMaximumBin();
	354	sigma=0;
	355	f1=f2=0;
	356	for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSYv->GetBinContent(i);
	357	for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
	358	for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
	359	MediaFondo=(f1+f2)/2;
	360	for(i=0;i<nbinxy;i++) {
	361	if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	362	VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
	363	sigma=hITSYv->GetBinCenter(BinMax)-hITSYv->GetBinCenter(i);
	364	sigma=TMath::Abs(sigma);
	365	if(sigma==0) sigma=0.05;
	366	}
	367	}
	368
	369	/*cout << "f1 " <<f1 <<endl;
	370	cout << "f2 " <<f2 <<endl;
	371	cout << "GetMaximumBin " <<hITSYv->GetMaximumBin() <<endl;
	372	cout << "max " << hITSYv->GetBinContent(BinMax)<<endl;
	373	cout << "sigma " <<sigma <<endl;
	374	cout << "Fondo " << MediaFondo<< endl;
	375	cout << "nbinxy " <<nbinxy <<endl;*/
	376
	377	fy->SetParameter(0,max);
	378	fy->SetParameter(1,Vzero[1]);
	379	fy->SetParameter(2,sigma);
	380	fy->SetParameter(3,MediaFondo);
	381
	382	hITSYv->Fit("fy","RMEQ0");
504de69b	383
6b88f180	384	fSNR[1] = fy->GetParameter(0)/fy->GetParameter(3);
	385	if(fSNR[1]<0.) {
	386	cout << "\nNegative Signal to noise ratio for y!!!" << endl;
	387	cout << "The algorithm cannot find the y vertex position." << endl;
	388	exit(123456789);
	389	}
	390	else
	391	{
	392	fPosition[1]=fy->GetParameter(1);
	393	fResolution[1]=fy->GetParError(1);
	394	}
	395
	396	niter++;
	397
	398	Vzero[0] = fPosition[0];
	399	Vzero[1] = fPosition[1];
	400	Vzero[2] = fPosition[2];
	401
	402	if(niter<3) goto start; // number of iterations
	403
	404
	405	cout<<"Number of iterations: "<<niter<<endl;
	406
	407	delete [] Z1;
	408	delete [] Z2;
	409	delete [] Y1;
	410	delete [] Y2;
	411	delete [] X1;
	412	delete [] X2;
	413	delete [] r1;
	414	delete [] r2;
	415	delete [] phi1;
	416	delete [] phi2;
	417	delete [] VectorBinZ;
	418	delete [] VectorBinXY;
	419
	420	delete hITSZv;
	421	delete hITSXv;
	422	delete hITSYv;
504de69b	423
	424	}
	425
	426
	427	//______________________________________________________________________________
	428
	429	AliITSVertex::~AliITSVertex() {
	430	delete [] fPosition;
	431	delete [] fResolution;
	432	delete [] fSNR;
	433	}
	434
	435	//______________________________________________________________________________
	436
504de69b	437	Double_t AliITSVertex::PhiFunc(Float_t p[]) {
6b88f180	438	Double_t phi=0;
	439	if(p[1]>0 && p[0]>0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578);
	440	if(p[1]>0 && p[0]<0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+180;
	441	if(p[1]<0 && p[0]<0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+180;
	442	if(p[1]<0 && p[0]>0) phi=(TMath::ATan((Double_t)(p[1]/p[0]))*57.29578)+360;
	443	return phi;
504de69b	444	}
6b88f180	445
504de69b	446	//______________________________________________________________________________
504de69b	447
6b88f180	448