//macro to read mini root data
{

// Clear ROOT environment
        gROOT.Reset();
// Switch on ROOT timer
        gROOT.Time();
        gROOT->SetStyle("Plain");

        Int_t MaxEvents = 1000;
// Create a T49Run object
        T49Run *run = new T49Run();
        run->SetVerbose(kFALSE);



        Char_t *RunType="20G+-20GeV-central-03A";   
        Int_t StartAtRun = 4883; //4881    
        Int_t EndAtRun = 4899;
        Int_t eventCount = 0;

// Define a pointer to an T49EventRoot object
        T49EventRoot    *event;
// Define a pointer to an T49ParticleRoot object
        T49ParticleRoot *track;

// Define my own variables (number of charged part.)
	Int_t plus1;
	Int_t minus1;
        Int_t all;
        double plus_pt;
        double minus_pt;
        double plus_ptkw;
        double minus_ptkw;
        double all_pt;
        double all_ptkw; 



        ofstream *out = new ofstream;
        out->open("20_mini.txt");

 //       ofstream *online = new ofstream;
 //       online->open("online_20.text");


// Loop over events in the data file
        while ((event = (T49EventRoot *) 
run->GetNextEvent(RunType,StartAtRun,EndAtRun)) && (eventCount < 
MaxEvents)) {

// find primary vertex
     T49Vertex *vertex = event->GetPrimaryVertex();
     T49Vertex  *bpd = event->GetBPDVertex();

     double ntf=vertex->GetNTrkFit();
     double nto=vertex->GetNTrkOut();
     double ratio=ntf/nto;


//vertex cuts:
   if((vertex->GetPchi2()>0)
   &&(vertex->GetIflag()==0)
   &&(event->GetVertexX()>-0.25)
   &&(event->GetVertexX()<0.2)
   &&(event->GetVertexY()>-0.2)
   &&(event->GetVertexY()<0.2)
   &&(event->GetVertexZ()>-581.3)
   &&(event->GetVertexZ()<-580.8)
//   &&(event->GetEveto()<...)
   &&(nto!=0)
   &&(ratio>0.25))


{
//*online<<ratio<<'\t'<<event->GetVertexX()<<'\t'<<event->GetVertexY()<<'\t';
//*online<<event->GetVertexZ()<<endl;

//cout<<event->GetVertexZ()<<'\t'<<bpd->GetZ()<<endl;

// Get a list of all primary particles in the event
           TClonesArray *List = event->GetPrimaryParticles();
// Determine the number of primary particles
           Int_t max = List->GetEntries();
// start to count negative and positive particles:
	   plus1=0;
	   minus1=0;
           all=0; 
             plus_pt=0;
             minus_pt=0;
             plus_ptkw=0;
             minus_ptkw=0;
             all_pt=0;
             all_ptkw=0;
    

// Loop over all particles
           for(Int_t i=0;i<max;i++)
           {
               track = (T49ParticleRoot *) List->At(i);
 double np=track->GetNPoint();
 double nmp=track->GetNMaxPoint();

 double angle=(atan2(track->GetPy(), track->GetPx()))*(180.0/3.14);
 double rapidity=track->GetRap(0.1396);
 double ycms=rapidity-1.88;
 double Z=(rapidity-1.88)/1.88;

 if(track->GetCharge()<0)
 {
   if(angle<0)
   angle=angle+360;
 angle=angle-180;
 }

double curve;

if(angle==0)
curve=1.5;
else
{
 if(ycms>1.0 && ycms<1.2)
 curve=1/((angle*angle)/600)-0.2;

 if(ycms>1.2 && ycms<1.4)
 curve=1/((angle*angle)/700)-0.2;

 if(ycms>1.4 && ycms<1.6)
 curve=1/((angle*angle)/1000)-0.2;

 if(ycms>1.6 && ycms<1.8)   
 curve=1/((angle*angle)/2600)-0.5;

 if(ycms>1.8 && ycms<2.0)
 curve=1/((angle*angle)/3000)-0.4;

 if(ycms>2.0 && ycms<2.2)
 curve=1/((angle*angle)/2500)-0.3;

 if(ycms>2.2 && ycms<2.4)
 curve=1/((angle*angle)/1800)-0.3;

 if(ycms>2.4 && ycms<2.6)
 curve=1/((angle*angle)/1000)-0.1;

}

//track cuts:
    if(((track->GetIflag()&0xFF000000) == 0)
    &&(track->GetNMaxPoint()>30)
    &&(np/nmp>0.5)  
    &&(track->GetZFirst()<200.0)
    &&(fabs(track->GetBx())<2.0)
    &&(fabs(track->GetBy())<1.0)
    &&(track->GetPt()>0.005)
    &&(track->GetPt()<1.5)
    &&(track->GetPt()<curve)
    &&(ycms>1.1)
    &&(ycms<2.6))


   {


     all=all+1;
     all_pt=all_pt+(track->GetPt());
     all_ptkw=all_ptkw+pow((track->GetPt()),2.0);

     if(track->GetCharge()>0)
     {
     plus1=plus1+1;
     plus_pt=plus_pt+(track->GetPt());
     plus_ptkw=plus_ptkw+pow((track->GetPt()),2.0);
     }

     if(track->GetCharge()<0)
     {
     minus1=minus1+1;
     minus_pt=minus_pt+(track->GetPt());
     minus_ptkw=minus_ptkw+pow((track->GetPt()),2.0);
     }


    }
           }  
               eventCount++;
  *out << event->GetEveto() << "\t" << "\t" << all << "\t" << all_pt << 
"\t" << all_ptkw << "\t" << "\t" << minus1 << "\t" << minus_pt << "\t" << 
minus_ptkw << "\t" << "\t" << plus1 << "\t" << plus_pt << "\t" << plus_ptkw << "\t" << endl;
        } 
 
} 
        out->close();
//        online->close();
}