lgorithm)</b>
    RooDataSet* d = w::model.generate(RooArgSet(w::x,w::y),1000) ;
    w::model.fitTo(*d) ;

    <b>// Make 2D plot on (x,y)</b>
    TH2* hh = w::model.createHistogram("x,y",40,40) ;
    hh->SetLineColor(kBlue) ;

    <b>// Make Projection on x (integrate over y)</b>
    RooPlot* framex = w::x.frame(Title("Data and p.d.f. projected on X")) ;
    d->plotOn(framex) ;
    w::model.plotOn(framex) ;

    <b>// Construct likelihood, profile likelihood in a, and draw the latter</b>
    RooAbsReal* nl