void test() {
  
  TH1D * numericHisto = new TH1D("histo1","Numeric Histogram", 100, 0, 99);
  

  for ( Int_t iEvent = 0; iEvent < 1000 ; iEvent++ ) {

    numericHisto->Fill(iEvent % 100);

  }

  numericHisto->Scale( 100. / numericHisto->Integral());

  TCanvas * can = new TCanvas;
  numericHisto->Draw();

  
  cout << "Numeric histo normalization factor " << numericHisto->GetNormFactor() << endl;


}