//macro to read mini root data
//witout analysis classes
{

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

        Int_t MaxEvents = 100;
// 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;


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


// 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;
     if(nto==0)
     ratio=0;
     else
     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))


{

//information to file run number and event number 
*out<<event->GetNRun()<<'\t'<<event->GetNEvent()<<endl;

//the same to screen
cout<<event->GetNRun()<<'\t'<<event->GetNEvent()<<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();


// 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;

//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)
    &&(ycms>1.1)      //forward rapidity
    &&(ycms<2.6))

   {

*out<<track->GetCharge()<<'\t'<<track->GetPx()<<'\t'<<track->GetPy()<<'\t'<<track->GetPz()<<endl;
cout<<track->GetCharge()<<'\t'<<track->GetPx()<<'\t'<<track->GetPy()<<'\t'<<track->GetPz()<<endl;

   }   //and of track cuts


           }  //and of track loop 
               eventCount++;


        }  //end of vertex cuts
 
} //end of loop over events
        out->close();

}   //end of main macro