Slow integration and plotting in RooFit

Roofit and RooStats
1

Hi, all.

I have a custom signal PDF that I’m using to fit 5 angular distributions. This signal PDF is multiplied by a 5d efficiency PDF and then added to a 5d background PDF.

When plotting any of the 5 angles, it takes an extremely long time to perform the integrations needed to plot the PDFs on top of my dataset. In fact, plotting a single angle can take upwards of 4 hours…

Needless to say, this slows things down way too much since I’m having to fiddle with parameters and refit fairly often. I really can’t afford to wait an entire day to get my plots back…

Is there any way to decrease the number of integration steps when performing plotOn for a complex PDF?

Thanks,
Brian

2

Hey
Don’t know if you managed to solve this (probably yes, since the thread is old) but I had this same issue and found adding RooFit::Precision(1) as a comand argument sped the plotting up.

data.plotOn(myplot);
big_complicated_pdf.plotOn(myplot, RooFit::Precision(1));

From wouter’s reply to a similar thread [url=https://root-forum.cern.ch/t/createprofile-very-slow/16202/1