Hi,

I’m trying to implement the integral of a PDF and it’s uncertainty as in Integral uncertainty with RooFit. I’ve run into what I think might be a bug. The values returned by a pdf and the value returned by the TF1 derived using asTF don’t match.

Here’s an example which reproduces the problem:

```
{
TFile f("limits/sig_chi_600_200_combined_meas_model.root");
RooWorkspace* wspace = (RooWorkspace*)f.Get("combined");
RooRealVar *obs_of = wspace->obj("obs_x_of");
RooProdPdf *sum_shape_of = wspace->obj("of_model");
RooArgSet *sum_params_of = sum_shape_of->getParameters(*obs_of);
RemoveConstantParameters(sum_params_of);
TF1* sum_tf = sum_shape_of->asTF(RooArgList(*obs_of), *sum_params_of);
obs_of->setVal(42);
cout << sum_shape_of->getVal() << "\t" << sum_tf->Eval(42) << endl;
}
```

I suspect this might be related to the normalization, but I don’t have any proof. I’ve also attached the workspace. I’d really appreciate it if someone could look into this or show me a workaround.

In particular, I’ve noticed that the RooRealIntegral object returned by createIntegral inherits a getPropagatedError method that doesn’t seem to work.

sig_chi_600_200_combined_meas_model.root (191 KB)