Apologies if this is a trivial question or was asked before, I could not find an answer on the web or on this forum.
We are using Roofit without HistFactory. We would like to perform a simultaneous fit of many regions, therefore we use a RooSimultaneous and fit it to a “combined” RooDataHist.
- If the pdfs in each region are binned in the same way (observable, binning), there are no problems and data are built using the following constructor:
RooDataHist::RooDataHist ( const char * name, const char * title, const RooArgList & vars, RooCategory & indexCat, std::map< std::string, RooDataHist *> dhistMap, Double_t wgt = 1.0 )
- issues arise when we want some regions to be binned differently or w.r.t other observables. We do not know how to create the corresponding RooDataHist. Indeed, it is clearly written in the documentation regarding the RooDataHist constructor we used previously:
The ranges and number of bins are taken from the input histogram and must be the same in all histograms
What are we missing? How can the ranges and number of bins can be different in each regions?
Thanks a lot for your help!