{
 gROOT->Reset();

#include <math.h>

   TCanvas *c1 = new TCanvas("c1","A Simple Graph
Example",200,10,700,500);
   const int colNum = 5;
   int palette[colNum];

  float green,red,blue;
  for (i=0;i<colNum;i++) 
  {
    switch(i)
    {
    case 0:  red=1.0;green=1.0;blue=1.0;break; // no chip read
    case 1:  red=1.0;green=0.0;blue=0.0;break; // no global register working
    case 2:  red=1.0;green=0.5;blue=0.5;break; // global register working
    case 3:  red=1.0;green=1.0;blue=0.0;break; // 1 col
    case 4:  red=1.0;green=0.5;blue=0.0;break; // 2
    case 5:  red=1.0;green=1.0;blue=0.5;break; // 3
    case 6:  red=0.0;green=1.0;blue=0.0;break; // 6
    case 7:  red=0.0;green=0.5;blue=0.0;break; // 7
    default: ;
    }
	
    TColor *color = new TColor(250+i,red,green,blue,"");
    palette[i] = 250+i;
    
  }
    
  gStyle->SetPalette(colNum,palette); 


   TH2D *histo2D = new TH2D("test","test contour",12,1,13,12,1,13);
   Int_t i,j;
   double val;
   int n=12;

   gStyle->SetOptStat(0);

  TF2 *F2 = new TF2("TF2","10*exp(-((x-6)^2/9)-((y-6)^2/9))",0,12,0,12);
   for (i=0;i<n;i++)
   {
     for (j=0;j<n;j++)
     {
       val = F2->Eval(i,j);
       histo2D->Fill(j+1,i+1,val);
     }
   }

  double levels[25];
  levels[0] = 0.5;
  levels[1] = 2;
  levels[2] = 9;


  histo2D->SetContour(3,levels); 


   histo2D->Draw("lego2z");

   c1->Update();
   delete F2;
}