void projection()
{
  TFile file("test1.root");
  TList *listatest = (TList*)file.Get("listatest");
  fFragPion= (TH2F*) (listatest->FindObject("fFragPion[1]"));
  fHistPtMC= (TH1F*) (listatest->FindObject("fHistPtMC"));

  TH1D *test =  fFragPion->ProjectionX("test",5,7,"");

  TCanvas *c6 = new TCanvas("c6","Fragmentation in pions",10,10,810,610);
  c6->Divide(3,1);
  c6->SetFillColor(0);    
  c6->cd(1);
  fHistPtMC->Draw();
  c6->cd(2);
  test->Draw();
  c6->cd(3);
  test->DrawCopy();
  c6->Update();
}