{
  gROOT->Reset();

// Create a new canvas.
  TCanvas *c1 = new TCanvas("c1","ccc",100,100,700,500);
  hpxpy  = new TH2F("hpxpy","py vs px",100,-4,4,100,-4,4);
  hpxpy2  = new TH2F("hpxpy2","py vs px",100,-4,4,100,-4,4);
// Fill histograms randomly
  gRandom->SetSeed();
  Float_t px, py, pz;
  Float_t px1, py1;
  for (Int_t i = 0; i < 25000; i++) {
     gRandom->Rannor(px,py);
     gRandom->Rannor(px1,py1);
     hpxpy->Fill(0.3 * px + 1, 0.7 * py+0.5);
     hpxpy->Fill(0.5 * px - 1, 0.5 * py-0.5);

     hpxpy2->Fill(px, px * 0.5 + 0.5 * py);
  }
//  boxes
  hpxpy->SetLineColor(kRed);
  hpxpy->Draw("box");
  hpxpy2->SetLineColor(kBlue);
  hpxpy2->Draw("boxsame");
// points (markers)
  TCanvas *c2 = new TCanvas("c2","boxes",200,200,700,500);
  hpxpy->SetMarkerColor(kRed);
  hpxpy->Draw();            // default is scatter plot
  hpxpy2->SetMarkerColor(kBlue);
  hpxpy2->Draw("same");
// points (markers)
  TCanvas *c3 = new TCanvas("c3","cont3",300,300,700,500);
  hpxpy->SetLineColor(kRed);
  hpxpy->Draw("cont3");            // default is scatter plot
  hpxpy2->SetLineColor(kBlue);
  hpxpy2->Draw("cont3same");

  c1->Modified();
  gDirectory = gROOT;
  
}