Hi

I am trying to get the ratio of two normalized plots

```
pad1->cd();
pad1->SetLogy();
Full->Scale(1/Full->Integral());
Fast->Scale(1/Fast->Integral());
Full->SetLineColor(kRed);
Fast->SetLineColor(kBlue);
Full->SetTitle("Comparison");
Full->Draw();
Fast->Draw("same");
///////now the ratio plot
pad2->cd();
///this is for the ratio
TH1F *ratio = (TH1F*)Full->Clone();
ratio->Sumw2();
ratio->Divide(Fast);
ratio->GetYaxis()->SetNdivisions(5);
ratio->Draw("pE");
```

my problem is that I get large error bars on the ratio plot (this does not happen if I dont normalize the plots) - Looks like that I am doing something wrong with the Sumw2, but cannot find what…

thanks