{
TH2F* bob = new TH2F("bob","test",10,0.,10.,10,0.,10.);
TH2F* bill = new TH2F("bill","test 2",10,0.,10,10,0.,10.);

bob->SetBinContent(1,3,5.);
bob->SetBinContent(2,4,2.);
bob->SetBinContent(3,5,4.);
bob->SetBinContent(4,6,6.);
bob->SetBinContent(5,7,8.);
bob->SetBinContent(6,8,2.);
bob->SetBinContent(7,9,3.);
bob->SetBinContent(8,1,4.);

//bill->SetBinContent(0,3,5 );
bill->SetBinContent(1,4,2.);
bill->SetBinContent(2,5,4.);
bill->SetBinContent(3,6,5.);
bill->SetBinContent(4,7,7.);
bill->SetBinContent(5,8,2 );
bill->SetBinContent(6,8,4.);
bill->SetBinContent(7,9,3.);
bill->SetBinContent(8,1,9.);

bob->Add(bill,-1.0);

bob->Draw("text");

}