Ticket #285: analysis.cpp

#include <stdexcept>
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>

#include <stdlib.h>
#include <signal.h>
#include <stdio.h>

#include "TROOT.h"
#include "TApplication.h"

#include "TFile.h"
#include "TClonesArray.h"
#include "TChain.h"

#include <cstdlib>
#include <TH2D.h>
#include <TCanvas.h>
#include <TRandom.h>
#include <TStyle.h>


#include "classes/DelphesClasses.h"

#include "external/ExRootAnalysis/ExRootTreeReader.h"
#include "external/ExRootAnalysis/ExRootProgressBar.h"

#include <iomanip>  
#include <cmath>

using namespace std;

int main() 
{

// Create chain of root trees
TChain chain("Delphes");
//chain.Add("events_7TeV.root");
chain.Add("events_new.root");


// Create object of class ExRootTreeReader
   ExRootTreeReader *treeReader = new ExRootTreeReader(&chain);
   Long64_t numberOfEntries = treeReader->GetEntries();
  
// Get pointers to branches used in this analysis

   TClonesArray *branchJet = treeReader->UseBranch("Jet");

  // define the number of B-jets in the event
   int NofBs = 0;

   // Loop over all events
   for(Int_t entry = 0; entry < numberOfEntries; ++entry)
   {
     // Load selected branches with data from specified event
     treeReader->ReadEntry(entry);

     // set the number of B-jets in the event to 0
     NofBs = 0;

     // If event contains at least 1 jet
     for(unsigned int i = 0; i < branchJet->GetEntries(); i++)
     {
       // Take first jet
       Jet *jet = (Jet*) branchJet->At(i);

       if (jet->BTag == 1) NofBs++;
     }
     cout << NofBs << endl;
   }

}