void TestBand()
{
  TCanvas* c2 = new TCanvas("Canv","Canv",160, 10,  0.6*1002, 0.6*852 );
  c2->SetFillColor(10);
  c2->cd();
  gPad->Clear();
  TGraphErrors *Gr=new TGraphErrors();
  for(int k=0;k<40;k++){
    Gr->SetPoint(k,k,2);
    Gr->SetPointError(k,0,0.2);    
  }
  Gr->SetFillColor(15);
  Gr->SetFillStyle(3002);
  Gr->Draw("4A*");  
}