/// \file /// \ingroup tutorial_roofit /// \notebook -js /// /// Basic functionality: plotting unbinned data with alternate and variable binnings /// /// \macro_image /// \macro_output /// \macro_code /// /// \date 07/2008 /// \author Wouter Verkerke #include "RooRealVar.h" #include "RooDataSet.h" #include "RooGaussModel.h" #include "RooDecay.h" #include "RooBMixDecay.h" #include "RooCategory.h" #include "RooBinning.h" #include "RooPlot.h" #include "TCanvas.h" #include "TAxis.h" #include "TH1.h" using namespace RooFit; void rf108_plotbinning() { // S e t u p m o d e l // --------------------- // Build a B decay p.d.f with mixing RooRealVar dt("dt", "dt", -20, 20); RooRealVar dm("dm", "dm", 0.472); RooRealVar tau("tau", "tau", 1.547); RooRealVar w("w", "mistag rate", 0.1); RooRealVar dw("dw", "delta mistag rate", 0.); RooCategory mixState("mixState", "B0/B0bar mixing state"); mixState.defineType("mixed", -1); mixState.defineType("unmixed", 1); RooCategory tagFlav("tagFlav", "Flavour of the tagged B0"); tagFlav.defineType("B0", 1); tagFlav.defineType("B0bar", -1); // Build a gaussian resolution model RooRealVar bias1("bias1", "bias1", 0); RooRealVar sigma1("sigma1", "sigma1", 0.1); RooGaussModel gm1("gm1", "gauss model 1", dt, bias1, sigma1); // Construct Bdecay (x) gauss RooBMixDecay bmix("bmix", "decay", dt, mixState, tagFlav, tau, dm, w, dw, gm1, RooBMixDecay::DoubleSided); // S a m p l e d a t a f r o m m o d e l // -------------------------------------------- // Sample 2000 events in (dt,mixState,tagFlav) from bmix RooDataSet *data = bmix.generate(RooArgSet(dt, mixState, tagFlav), 2000); // S h o w d t d i s t r i b u t i o n w i t h c u s t o m b i n n i n g // ------------------------------------------------------------------------------- // Make plot of dt distribution of data in range (-15,15) with fine binning for dt>0 and coarse binning for dt<0 // Create binning object with range (-15,15) RooBinning tbins(-15, 15); // Add 60 bins with uniform spacing in range (-15,0) tbins.addUniform(60, -15, 0); // Add 15 bins with uniform spacing in range (0,15) tbins.addUniform(15, 0, 15); // Make plot with specified binning RooPlot *dtframe = dt.frame(Range(-15, 15), Title("dt distribution with custom binning")); data->plotOn(dtframe, Binning(tbins)); bmix.plotOn(dtframe); // NB: Note that bin density for each bin is adjusted to that of default frame binning as shown // in Y axis label (100 bins --> Events/0.4*Xaxis-dim) so that all bins represent a consistent density distribution // S h o w m i x s t a t e a s y m m e t r y w i t h c u s t o m b i n n i n g // ------------------------------------------------------------------------------------ // Make plot of dt distribution of data asymmetry in 'mixState' with variable binning // Create binning object with range (-10,10) RooBinning abins(-10, 10); // Add boundaries at 0, (-1,1), (-2,2), (-3,3), (-4,4) and (-6,6) abins.addBoundary(0); abins.addBoundaryPair(1); abins.addBoundaryPair(2); abins.addBoundaryPair(3); abins.addBoundaryPair(4); abins.addBoundaryPair(6); // Create plot frame in dt RooPlot *aframe = dt.frame(Range(-10, 10), Title("mixState asymmetry distribution with custom binning")); // Plot mixState asymmetry of data with specified custom binning data->plotOn(aframe, Asymmetry(mixState), Binning(abins)); // Plot corresponding property of p.d.f bmix.plotOn(aframe, Asymmetry(mixState)); // Adjust vertical range of plot to sensible values for an asymmetry aframe->SetMinimum(-1.1); aframe->SetMaximum(1.1); // NB: For asymmetry distributions no density corrects are needed (and are thus not applied) // Draw plots on canvas TCanvas *c = new TCanvas("rf108_plotbinning", "rf108_plotbinning", 800, 400); c->Divide(2); c->cd(1); gPad->SetLeftMargin(0.15); dtframe->GetYaxis()->SetTitleOffset(1.6); dtframe->Draw(); c->cd(2); gPad->SetLeftMargin(0.15); aframe->GetYaxis()->SetTitleOffset(1.6); aframe->Draw(); }