{
   auto c1    = new TCanvas("c1","c1",600,400);
   auto hcol1 = new TH2F("hcol1","Option COLor example ",40,-4,4,40,-20,20);
   float px, py;
   for (Int_t i = 0; i < 25000; i++) {
      gRandom->Rannor(px,py);
      hcol1->Fill(px,5*py);
   }
   hcol1->Draw("COLZ");
}