{
   auto c4 = new TCanvas("c4","c4",600,400);
   c4->Divide(2,2);
   auto hscc = new TH2F("hscc","Cylindrical coordinates",20,-4,4,20,-20,20);
   float px, py;
   for (Int_t i = 0; i < 25000; i++) {
      gRandom->Rannor(px,py);
      hscc->Fill(px-1,5*py);
      hscc->Fill(2+0.5*px,2*py-10.,0.1);
   }
   c4->cd(1); hscc->Draw("SURF1 CYL");
   c4->cd(2); auto hspc = (TH2F*) hscc->DrawClone("SURF1 POL");
   hspc->SetTitle("Polar coordinates");
   c4->cd(3); auto hssc = (TH2F*) hscc->DrawClone("SURF1 SPH");
   hssc->SetTitle("Spherical coordinates");
   c4->cd(4); auto hsprpc = (TH2F*) hscc->DrawClone("SURF1 PSR");
   hsprpc->SetTitle("PseudoRapidity/Phi coordinates");
}