source: huonglan/NEWRELEASE/MERGEFILES/mergeFiles.C @ 11

void mergeFiles(TString TheTreeName = "T") {

  TChain *tdn = new TChain(TheTreeName);

  TString fSingT[63];
  TString fAllWj[63];
  TString fAllZj[63];

  TString vers = "v1";
  TString fRes[63];

  ifstream ftxt("listMCResFiles"+vers+".txt");
  for (int i = 0; i < 63; i++){
    ftxt >> fRes[i];
  }
  ftxt.close(); 

  for (int i = 0; i < 63; i++){
    cout << fRes[i] << endl;
  }

  //sum all the loose histos
  TH1F *hlooseTot = new TH1F("hlooseTot", "", 202, -2, 200);
  double binV[202];
  for (int i = 0; i < 202; i++){
    binV[i] = 0;
  }

//   m_njets = new TH1F("njets", "njets", 29, 1, 30);
//   fOutput->Add(m_njets);
  
//   m_njetsE = new TH1F("njetsE", "njetsE", 29, 1, 30);
//   fOutput->Add(m_njetsE);
  
//   m_njetsM = new TH1F("njetsM", "njetsM", 29, 1, 30);
//   fOutput->Add(m_njetsM);


  //sum all the njets histos
  TH1F *hnjet  = new TH1F("Njet",  "", 29, 1, 30);
  TH1F *hnjetE = new TH1F("NjetE", "", 29, 1, 30);
  TH1F *hnjetM = new TH1F("NjetM", "", 29, 1, 30);
  double njet[29], njetE[29], njetM[29];
  for (int i = 0; i < 29; i++){
    njet[i]  = 0;
    njetE[i] = 0;
    njetM[i] = 0;
  }

  TChain *tdW = new TChain(TheTreeName);
  for (int ifi = 0; ifi < 63; ifi++){
    std::cout << "Copying file " << fRes[ifi] << std::endl;
    TFile *f = TFile::Open(fRes[ifi]);
    TTree *t = (TTree*)f->Get("T");
    cout << "Entries Number of " << fRes[ifi] << " = " << t->GetEntries() << endl;
    tdW->Add(fRes[ifi]); 

    TH1F *hloose = (TH1F*)f->Get("loose");
    for (int ib = 1; ib < 203; ib++){
      double bb   = hloose->GetBinContent(ib);
      binV[ib-1] += bb;
    }
    TH1F *nj  = (TH1F*)f->Get("njets");
    TH1F *njE = (TH1F*)f->Get("njetsE");
    TH1F *njM = (TH1F*)f->Get("njetsM");
    for (int ib = 1; ib < 30; ib++){
      double bb  = nj->GetBinContent(ib);
      double bbE = njE->GetBinContent(ib);
      double bbM = njM->GetBinContent(ib);
      njet[ib-1]  += bb;
      njetE[ib-1] += bbE;
      njetM[ib-1] += bbM;
    }
  }

  for (int i = 0; i < 202; i++){
    hlooseTot->SetBinContent(i+1,binV[i]);
  }
  for (int i = 0; i < 29; i++){
    hnjet->SetBinContent(i+1,njet[i]);
    hnjetE->SetBinContent(i+1,njetE[i]);
    hnjetM->SetBinContent(i+1,njetM[i]);
  }

  TFile *fn = new TFile("resAllMCFiles"+vers+".root","RECREATE");
//   TTree *tW = tdW->CloneTree(0);
//   tW->SetName("T");
//   tW->SetAutoSave();
//   gROOT->cd();
  
  int nCount = 0;
  
//   for (int iev = 0; iev < tdW->GetEntries(); iev++) {
//     nCount ++;
//     if (iev%1000 == 0) std::cout << "Reading event " << iev << std::endl;
//     tdW->GetEntry(iev);
//     tW->Fill();
//   }
  fn->cd();
  //tW->Write("",TObject::kOverwrite);
  hlooseTot->Write();
  hnjet->Write();
  hnjetE->Write();
  hnjetM->Write();
  fn->Close();

  cout << "nCount = " << nCount << endl;

}