[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 <Riostream.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() {
    // Default Constructor
	
	Int_t i;
	for (i = 0; i < 3; i++) {
	    fPosition[i]   = 0.0;
    	fResolution[i] = 0.0;
	    fSNR[i]        = 0.0;
	}
}
//______________________________________________________________________
AliITSVertex::~AliITSVertex() {
    // Default Destructor
}
//______________________________________________________________________
void AliITSVertex::Exec(){

   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;
   
}
//______________________________________________________________________
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>
4ae5bbc4	8	#include <Riostream.h>
504de69b	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
504de69b	39
cd77595e	40	//______________________________________________________________________
	41	AliITSVertex::AliITSVertex() {
	42	// Default Constructor
c37f6565	43
	44	Int_t i;
	45	for (i = 0; i < 3; i++) {
	46	fPosition[i] = 0.0;
	47	fResolution[i] = 0.0;
	48	fSNR[i] = 0.0;
	49	}
cd77595e	50	}
	51	//______________________________________________________________________
	52	AliITSVertex::~AliITSVertex() {
c37f6565	53	// Default Destructor
cd77595e	54	}
	55	//______________________________________________________________________
	56	void AliITSVertex::Exec(){
504de69b	57
504de69b	58	AliITS* aliits =(AliITS *)gAlice->GetDetector("ITS");
	59	AliITSgeom g2 = ((AliITS)aliits)->GetITSgeom();
	60
	61	TClonesArray *recpoints = aliits->RecPoints();
	62	AliITSRecPoint *pnt;
504de69b	63
6b88f180	64	Int_t NoPoints1 = 0;
504de69b	65	Int_t NoPoints2 = 0;
	66	Double_t Vzero[3];
	67	Double_t AsPar[2];
	68
6b88f180	69	//------------ Rough Vertex evaluation ---------------------------------
504de69b	70
6b88f180	71	Int_t i,npoints,ipoint,j,k,max,BinMax;
504de69b	72	Double_t ZCentroid;
	73	Float_t l[3], p[3];
	74
6b88f180	75	Double_t mxpiu = 0;
	76	Double_t mxmeno = 0;
	77	Double_t mypiu = 0;
	78	Double_t mymeno = 0;
	79
504de69b	80	TH1F *hITSz1 = new TH1F("hITSz1","",100,-14.35,14.35);
	81
	82	for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++)
	83	{
6b88f180	84	aliits->ResetRecPoints();
	85	gAlice->TreeR()->GetEvent(i);
	86	npoints = recpoints->GetEntries();
	87
	88	for (ipoint=0;ipoint<npoints;ipoint++) {
	89	pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
	90	l[0]=pnt->GetX();
	91	l[1]=0;
	92	l[2]=pnt->GetZ();
	93	g2->LtoG(i, l, p);
	94	if(i<80 && TMath::Abs(p[2])<14.35) {
	95	if(p[0]>0) mxpiu++;
	96	if(p[0]<0) mxmeno++;
	97	if(p[1]>0) mypiu++;
	98	if(p[1]<0) mymeno++;
	99	hITSz1->Fill(p[2]);
	100	}
	101	if(i>=80 && TMath::Abs(p[2])<14.35) NoPoints2++;
504de69b	102	}
	103	}
	104
	105	NoPoints1 = (Int_t)(hITSz1->GetEntries());
6b88f180	106
504de69b	107	AsPar[0] = (mxpiu-mxmeno)/(mxpiu+mxmeno);
	108	AsPar[1] = (mypiu-mymeno)/(mypiu+mymeno);
	109
6b88f180	110	Vzero[0] = 5.24441*AsPar[0];
6b88f180	111	Vzero[1] = 5.24441*AsPar[1];
504de69b	112
	113	ZCentroid= TMath::Abs(hITSz1->GetMean());
	114	Vzero[2] = -5.31040e-02+1.42198ZCentroid+7.44718e-01TMath::Power(ZCentroid,2)
6b88f180	115	-5.73426e-01TMath::Power(ZCentroid,3)+2.01500e-01TMath::Power(ZCentroid,4)
504de69b	116	-3.34118e-02TMath::Power(ZCentroid,5)+2.20816e-03TMath::Power(ZCentroid,6);
	117
	118	if(hITSz1->GetMean()<0) Vzero[2] = -Vzero[2];
	119
dbd283ec	120	/*cout << "\nXvzero: " << Vzero[0] << " cm" << "";
504de69b	121	cout << "\nYvzero: " << Vzero[1] << " cm" << "";
dbd283ec	122	cout << "\nZvzero: " << Vzero[2] << " cm" << "\n";*/
504de69b	123
504de69b	124	delete hITSz1;
504de69b	125
6b88f180	126	Double_t dphi,r,DeltaZ,a,b;
504de69b	127	Int_t np1=0;
504de69b	128	Int_t np2=0;
6b88f180	129	Int_t niter=0;
	130
	131	Double_t DeltaPhiZ = 0.08;
	132
	133	Float_t B[3];
	134	Float_t origin[3];
	135	for(Int_t okm=0;okm<3;okm++) origin[okm]=0;
	136	gAlice->Field()->Field(origin,B);
504de69b	137
6b88f180	138	DeltaPhiZ = DeltaPhiZ*B[2]/2;
	139	Double_t DeltaPhiXY = 1.0;
	140
	141	// cout << "\nDeltaPhiZ: " << DeltaPhiZ << " deg" << "\n";
	142	// cout << "DeltaPhiXY: " << DeltaPhiXY << " deg" << "\n";
	143
504de69b	144	Double_t Z1, Z2, Y1, Y2, X1, X2, phi1, phi2, r1, r2;
	145	Z1=new Double_t[NoPoints1];
	146	Z2=new Double_t[NoPoints2];
	147	Y1=new Double_t[NoPoints1];
	148	Y2=new Double_t[NoPoints2];
	149	X1=new Double_t[NoPoints1];
	150	X2=new Double_t[NoPoints2];
	151	phi1=new Double_t[NoPoints1];
	152	phi2=new Double_t[NoPoints2];
	153	r1=new Double_t[NoPoints1];
	154	r2=new Double_t[NoPoints2];
6b88f180	155
	156	DeltaZ = 4.91617e-01+2.67567e-02Vzero[2]+1.49626e-02TMath::Power(Vzero[2],2);
	157	Float_t MulFactorZ = 28000./(Float_t)NoPoints1;
	158	Int_t nbin=(Int_t)((DeltaZ/0.005)/MulFactorZ);
	159	Int_t nbinxy=250;
	160	Int_t VectorBinZ,VectorBinXY;
	161	VectorBinZ=new Int_t[nbin];
	162	VectorBinXY=new Int_t[nbinxy];
	163	Float_t f1= 0;
	164	Float_t f2= 0;
	165	Double_t sigma,MediaFondo;
	166
	167	TH1D *hITSZv = new TH1D("hITSZv","",nbin,Vzero[2]-DeltaZ,Vzero[2]+DeltaZ);
	168	TH1D *hITSXv = new TH1D("hITSXv","",nbinxy,-3,3);
	169	TH1D *hITSYv = new TH1D("hITSYv","",nbinxy,-3,3);
504de69b	170
6b88f180	171	// cout << "DeltaZeta: " << DeltaZ << " cm" << "\n";
504de69b	172
6b88f180	173
6b88f180	174	start:
504de69b	175
6b88f180	176	hITSZv->Add(hITSZv,-1.);
	177	hITSXv->Add(hITSXv,-1.);
	178	hITSYv->Add(hITSYv,-1.);
504de69b	179
6b88f180	180	np1=np2=0;
504de69b	181
6b88f180	182
	183
	184	for(i=g2->GetStartSPD();i<=g2->GetLastSPD();i++)
	185	{
	186	aliits->ResetRecPoints();
	187	gAlice->TreeR()->GetEvent(i);
	188	npoints = recpoints->GetEntries();
	189	for (ipoint=0;ipoint<npoints;ipoint++) {
	190
	191	pnt = (AliITSRecPoint*)recpoints->UncheckedAt(ipoint);
	192	l[0]=pnt->GetX();
	193	l[1]=0;
	194	l[2]=pnt->GetZ();
	195	g2->LtoG(i, l, p);
	196
	197	if(i<80 && TMath::Abs(p[2])<14.35) {
	198	p[0]=p[0]-Vzero[0];
	199	p[1]=p[1]-Vzero[1];
	200	r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
	201	Y1[np1]=p[1];
	202	X1[np1]=p[0];
	203	Z1[np1]=p[2];
	204	r1[np1]=r;
	205	phi1[np1]=PhiFunc(p);
	206	np1++;
	207	}
	208
	209	if(i>=80 && TMath::Abs(p[2])<14.35) {
	210	p[0]=p[0]-Vzero[0];
	211	p[1]=p[1]-Vzero[1];
	212	r=TMath::Sqrt(TMath::Power(p[0],2)+TMath::Power(p[1],2));
	213	Y2[np2]=p[1];
	214	X2[np2]=p[0];
	215	Z2[np2]=p[2];
	216	r2[np2]=r;
	217	phi2[np2]=PhiFunc(p);
	218	np2++;
	219	}
	220
	221	}
	222	}
504de69b	223
6b88f180	224	//------------------ Correlation between rec points ----------------------
6b88f180	225
dbd283ec	226	//cout << "\nNo. of Points on the two pixel layers: "<<np1<<" "<<np2<<endl;
504de69b	227
504de69b	228	for(j=0; j<(np2)-1; j++) {
6b88f180	229	for(k=0; k<(np1)-1; k++) {
	230	dphi=TMath::Abs(phi1[k]-phi2[j]);
	231	if(dphi>180) dphi = 360-dphi;
	232	if(dphi<DeltaPhiZ && TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-Vzero[2])
	233	<DeltaZ) hITSZv->Fill(Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1));
	234	}
	235	}
	236
	237	//cout << "\nNumber of used pairs: \n";
	238	//cout << hITSZv->GetEntries() << '\n' << '\n';
	239	a = Vzero[2]-DeltaZ;
	240	b = Vzero[2]+DeltaZ;
	241	max=(Int_t) hITSZv->GetMaximum();
	242	BinMax=hITSZv->GetMaximumBin();
	243	sigma=0;
	244	for(i=0;i<nbin;i++) VectorBinZ[i]=(Int_t)hITSZv->GetBinContent(i);
	245	for(i=0;i<10;i++) f1=f1+VectorBinZ[i]/10;
	246	for(i=nbin-10;i<nbin;i++) f2=f2+VectorBinZ[i]/10;
	247	MediaFondo=(f1+f2)/2;
	248	for(i=0;i<nbin;i++) {
	249	if(VectorBinZ[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	250	VectorBinZ[i]-MediaFondo<(max-MediaFondo)*0.7) {
	251	sigma=hITSZv->GetBinCenter(BinMax)-hITSZv->GetBinCenter(i);
	252	sigma=TMath::Abs(sigma);
	253	if(sigma==0) sigma=0.05;
	254	}
504de69b	255	}
504de69b	256
dbd283ec	257	/*cout << "f1 " <<f1 <<endl;
6b88f180	258	cout << "f2 " <<f2 <<endl;
	259	cout << "GetMaximumBin " <<hITSZv->GetMaximumBin() <<endl;
	260	cout << "nbin " <<nbin <<endl;
	261	cout << "max " << hITSZv->GetBinContent(BinMax)<<endl;
	262	cout << "sigma " <<sigma <<endl;
dbd283ec	263	cout << "Fondo " << MediaFondo<< endl;*/
504de69b	264
6b88f180	265	TF1 fz = new TF1 ("fz","([0]exp(-0.5((x-[1])/[2])((x-[1])/[2])))+[3]",a,b);
504de69b	266
6b88f180	267	fz->SetParameter(0,max);
	268	if(niter==0) {Double_t temp = hITSZv->GetBinCenter(BinMax); Vzero[2]=temp;}
	269	fz->SetParameter(1,Vzero[2]);
	270	fz->SetParameter(2,sigma);
	271	fz->SetParameter(3,MediaFondo);
	272	fz->SetParLimits(2,0,999);
	273	fz->SetParLimits(3,0,999);
504de69b	274
6b88f180	275	hITSZv->Fit("fz","RMEQ0");
	276
	277	fSNR[2] = fz->GetParameter(0)/fz->GetParameter(3);
	278	if(fSNR[2]<0.) {
	279	cout << "\nNegative Signal to noise ratio for z!!!" << endl;
	280	cout << "The algorithm cannot find the z vertex position." << endl;
	281	exit(123456789);
504de69b	282	}
	283	else
	284	{
6b88f180	285	fPosition[2] = fz->GetParameter(1);
504de69b	286	if(fPosition[2]<0)
	287	{
	288	fPosition[2]=fPosition[2]-TMath::Abs(fPosition[2])*1.11/10000;
	289	}
	290	else
	291	{
	292	fPosition[2]=fPosition[2]+TMath::Abs(fPosition[2])*1.11/10000;
	293	}
	294	}
6b88f180	295	fResolution[2] = fz->GetParError(1);
504de69b	296
6b88f180	297
	298
	299	for(j=0; j<(np2)-1; j++) {
	300	for(k=0; k<(np1)-1; k++) {
	301	dphi=TMath::Abs(phi1[k]-phi2[j]);
	302	if(dphi>180) dphi = 360-dphi;
	303	if(dphi>DeltaPhiXY) continue;
	304	if(TMath::Abs((Z1[k]-(Z2[j]-Z1[k])/((r2[j]/r1[k])-1))-fPosition[2])
	305	<4*fResolution[2]) {
	306	hITSXv->Fill(Vzero[0]+(X2[j]-((X2[j]-X1[k])/(Y2[j]-Y1[k]))*Y2[j]));
	307	hITSYv->Fill(Vzero[1]+(Y2[j]-((Y2[j]-Y1[k])/(X2[j]-X1[k]))*X2[j]));
	308	}
	309	}
	310	}
	311
	312	TF1 *fx = new TF1
	313	("fx","([0]exp(-0.5((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[0]-0.5,Vzero[0]+0.5);
	314
	315	max=(Int_t) hITSXv->GetMaximum();
	316	BinMax=hITSXv->GetMaximumBin();
	317	sigma=0;
	318	f1=f2=0;
	319	for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSXv->GetBinContent(i);
	320	for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
	321	for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
	322	MediaFondo=(f1+f2)/2;
	323	for(i=0;i<nbinxy;i++) {
	324	if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	325	VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
	326	sigma=hITSXv->GetBinCenter(BinMax)-hITSXv->GetBinCenter(i);
	327	sigma=TMath::Abs(sigma);
	328	if(sigma==0) sigma=0.05;
	329	}
	330	}
	331
	332	/*cout << "f1 " <<f1 <<endl;
	333	cout << "f2 " <<f2 <<endl;
	334	cout << "GetMaximumBin " <<hITSXv->GetMaximumBin() <<endl;
	335	cout << "max " << hITSXv->GetBinContent(BinMax)<<endl;
	336	cout << "sigma " <<sigma <<endl;
	337	cout << "Fondo " << MediaFondo<< endl;
	338	cout << "nbinxy " <<nbinxy <<endl;*/
	339
	340	fx->SetParameter(0,max);
	341	fx->SetParameter(1,Vzero[0]);
	342	fx->SetParameter(2,sigma);
	343	fx->SetParameter(3,MediaFondo);
	344
	345	hITSXv->Fit("fx","RMEQ0");
	346
	347	fSNR[0] = fx->GetParameter(0)/fx->GetParameter(3);
	348	if(fSNR[0]<0.) {
	349	cout << "\nNegative Signal to noise ratio for x!!!" << endl;
	350	cout << "The algorithm cannot find the x vertex position." << endl;
	351	exit(123456789);
	352	}
	353	else
	354	{
	355	fPosition[0]=fx->GetParameter(1);
	356	fResolution[0]=fx->GetParError(1);
	357	}
504de69b	358
6b88f180	359	TF1 *fy = new TF1
	360	("fy","([0]exp(-0.5((x-[1])/[2])*((x-[1])/[2])))+[3]",Vzero[1]-0.5,Vzero[1]+0.5);
	361
	362	max=(Int_t) hITSYv->GetMaximum();
	363	BinMax=hITSYv->GetMaximumBin();
	364	sigma=0;
	365	f1=f2=0;
	366	for(i=0;i<nbinxy;i++) VectorBinXY[i]=(Int_t)hITSYv->GetBinContent(i);
	367	for(i=0;i<10;i++) f1=f1+VectorBinXY[i]/10;
	368	for(i=nbinxy-10;i<nbinxy;i++) f2=f2+VectorBinXY[i]/10;
	369	MediaFondo=(f1+f2)/2;
	370	for(i=0;i<nbinxy;i++) {
	371	if(VectorBinXY[i]-MediaFondo>(max-MediaFondo)*0.4 &&
	372	VectorBinXY[i]-MediaFondo<(max-MediaFondo)*0.7) {
	373	sigma=hITSYv->GetBinCenter(BinMax)-hITSYv->GetBinCenter(i);
	374	sigma=TMath::Abs(sigma);
	375	if(sigma==0) sigma=0.05;
	376	}
	377	}
	378
	379	/*cout << "f1 " <<f1 <<endl;
	380	cout << "f2 " <<f2 <<endl;
	381	cout << "GetMaximumBin " <<hITSYv->GetMaximumBin() <<endl;
	382	cout << "max " << hITSYv->GetBinContent(BinMax)<<endl;
	383	cout << "sigma " <<sigma <<endl;
	384	cout << "Fondo " << MediaFondo<< endl;
	385	cout << "nbinxy " <<nbinxy <<endl;*/
	386
	387	fy->SetParameter(0,max);
	388	fy->SetParameter(1,Vzero[1]);
	389	fy->SetParameter(2,sigma);
	390	fy->SetParameter(3,MediaFondo);
	391
	392	hITSYv->Fit("fy","RMEQ0");
504de69b	393
6b88f180	394	fSNR[1] = fy->GetParameter(0)/fy->GetParameter(3);
	395	if(fSNR[1]<0.) {
	396	cout << "\nNegative Signal to noise ratio for y!!!" << endl;
	397	cout << "The algorithm cannot find the y vertex position." << endl;
	398	exit(123456789);
	399	}
	400	else
	401	{
	402	fPosition[1]=fy->GetParameter(1);
	403	fResolution[1]=fy->GetParError(1);
	404	}
	405
	406	niter++;
	407
	408	Vzero[0] = fPosition[0];
	409	Vzero[1] = fPosition[1];
	410	Vzero[2] = fPosition[2];
	411
	412	if(niter<3) goto start; // number of iterations
	413
	414
	415	cout<<"Number of iterations: "<<niter<<endl;
	416
	417	delete [] Z1;
	418	delete [] Z2;
	419	delete [] Y1;
	420	delete [] Y2;
	421	delete [] X1;
	422	delete [] X2;
	423	delete [] r1;
	424	delete [] r2;
	425	delete [] phi1;
	426	delete [] phi2;
	427	delete [] VectorBinZ;
	428	delete [] VectorBinXY;
	429
	430	delete hITSZv;
	431	delete hITSXv;
	432	delete hITSYv;
504de69b	433
504de69b	434	}
cd77595e	435	//______________________________________________________________________
504de69b	436	Double_t AliITSVertex::PhiFunc(Float_t p[]) {
cd77595e	437	Double_t phi=0;
504de69b	438
cd77595e	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;
	444	}
6b88f180	445
cd77595e	446	//______________________________________________________________________