TopJetFWLiteAnalyzer.cc

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#include <memory>
#include <string>
#include <cstdlib>
#include <sstream>
#include <fstream>
#include <iostream>
 
#include "FWCore/FWLite/interface/FWLiteEnabler.h"
#include "DataFormats/PatCandidates/interface/Jet.h"
 
#include "TopQuarkAnalysis/Examples/bin/NiceStyle.cc"
#include "TopQuarkAnalysis/Examples/interface/RootSystem.h"
#include "TopQuarkAnalysis/Examples/interface/RootHistograms.h"
#include "TopQuarkAnalysis/Examples/interface/RootPostScript.h"
 
int main(int argc, char* argv[]) {
  if (argc < 3) {
    // -------------------------------------------------
    std::cerr << "ERROR:: "
              << "Wrong number of arguments! Please specify:" << std::endl
              << "        * filepath" << std::endl
              << "        * process name" << std::endl;
    // -------------------------------------------------
    return -1;
  }
 
  // load framework libraries
  gSystem->Load("libFWCoreFWLite");
  FWLiteEnabler::enable();
 
  // set nice style for histograms
  setNiceStyle();
 
  // define some histograms
  TH1I* noJets = new TH1I("noJets", "N_{Jets}", 10, 0, 10);
  TH1F* ptJets = new TH1F("ptJets", "pt_{Jets}", 100, 0., 300.);
  TH1F* enJets = new TH1F("enJets", "energy_{Jets}", 100, 0., 300.);
  TH1F* etaJets = new TH1F("etaJets", "eta_{Jets}", 100, -3., 3.);
  TH1F* phiJets = new TH1F("phiJets", "phi_{Jets}", 100, -5., 5.);
 
  // -------------------------------------------------
  std::cout << "open  file: " << argv[1] << std::endl;
  // -------------------------------------------------
  TFile* inFile = TFile::Open(argv[1]);
  TTree* events_ = nullptr;
  if (inFile)
    inFile->GetObject("Events", events_);
  if (events_ == nullptr) {
    // -------------------------------------------------
    std::cerr << "ERROR:: "
              << "Unable to retrieve TTree Events!" << std::endl
              << "        Eighter wrong file name or the the tree doesn't exists" << std::endl;
    // -------------------------------------------------
    return -1;
  }
 
  // acess branch of elecs
  char jetsName[50];
  sprintf(jetsName, "patJets_selectedPatJets__%s.obj", argv[2]);
  TBranch* jets_ = events_->GetBranch(jetsName);
  assert(jets_ != nullptr);
 
  // loop over events and fill histograms
  std::vector<pat::Jet> jets;
  int nevt = events_->GetEntries();
 
  // -------------------------------------------------
  std::cout << "start looping " << nevt << " events..." << std::endl;
  // -------------------------------------------------
  for (int evt = 0; evt < nevt; ++evt) {
    // set branch address
    jets_->SetAddress(&jets);
    // get event
    jets_->GetEntry(evt);
    events_->GetEntry(evt, 0);
 
    // -------------------------------------------------
    if (evt > 0 && !(evt % 10))
      std::cout << "  processing event: " << evt << std::endl;
    // -------------------------------------------------
 
    // fill histograms
    noJets->Fill(jets.size());
    for (unsigned idx = 0; idx < jets.size(); ++idx) {
      // fill histograms
      ptJets->Fill(jets[idx].pt());
      enJets->Fill(jets[idx].energy());
      etaJets->Fill(jets[idx].eta());
      phiJets->Fill(jets[idx].phi());
    }
  }
  // -------------------------------------------------
  std::cout << "close file" << std::endl;
  // -------------------------------------------------
  inFile->Close();
 
  // save histograms to file
  TFile outFile("analyzeJets.root", "recreate");
  outFile.mkdir("analyzeJet");
  outFile.cd("analyzeJet");
  noJets->Write();
  ptJets->Write();
  enJets->Write();
  etaJets->Write();
  phiJets->Write();
  outFile.Close();
 
  // free allocated space
  delete noJets;
  delete ptJets;
  delete enJets;
  delete etaJets;
  delete phiJets;
 
  return 0;
}