RooHistPdf binning and Convolution in CMSSW

Dear Experts,

Unfortunateley I have two problems that I can’t solve.

  1. RooHistPdf Normalization:
    If I apply binning to my RooDataHist to reduce statistical fluctuations in my RooHistPdf the produced PDF doesn’t take the binning in account when it normalizes, so I can’t use it. I am sure, this problem can be solved with one simple command, which I just can’t find… example code:

RooRealVar Jpsict(“Jpsict”,“c #tau [mm]”,-1,2.5);

RooDataSet* data = (RooDataSet*)fIn->Get(“data”);

RooBinning rb(-1,2.5);

RooDataHist realdatahist(“realdatahist”,“realdatahist”,RooArgSet(Jpsict),*data);
RooHistPdf histNonPrompt(“histNonPrompt”,“histNonPrompt”,Jpsict,realdatahist);

  1. Convolution in CMSSW framework:
    I have to use convolution for my fit (other than RooDecay), but as I have to use the RooFit version (5.25.02-cms6) from the Root implemented in the CMSSW framework (ROOT 5.22/00d), I don’t know how I can do it, as there is no FFTW package compiled. Is there any possibility to implement this FFTW package from “outside”?

Thank you for your time,

Valentin Knünz

Hi Valentin,

Use the latest RooFit version (3.13) would solve both problems. I don’t know what
CMS plans are to build a ROOT release with this version (I’m in ATLAS…)