Obtain VisualizeError values in RooFit

Hi ROOT team,

I am using the VisualizeError plot option in RooFit, similar to the example here:
root.cern.ch/root/html/tutorial … ror.C.html

After generation, I want to access those band values for further study, but the corresponding error on the ‘model’ owned by the frame has not been set. How do I access the error band values?