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TestNonCentral.C File Reference

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␛[1mRooFit v3.60 -- Developed by Wouter Verkerke and David Kirkby␛[0m
Copyright (C) 2000-2013 NIKHEF, University of California & Stanford University
All rights reserved, please read http://roofit.sourceforge.net/license.txt
[#1] INFO:InputArguments -- RooNonCentralChiSquare sum being forced
[#0] WARNING:Eval -- RooNonCentralChiSquare did not converge: for x=36 k=2.01, lambda=5 fractional error = 0.00108172
either adjust tolerance with SetErrorTolerance(tol) or max_iter with SetMaxIter(max_it)
using namespace RooFit;
void TestNonCentral()
RooWorkspace w("w");
// k <2, must use sum
// kk > 2 can use bessel
// kk > 2, force sum
((RooNonCentralChiSquare *)w.pdf("nccc"))->SetForceSum(true);
// a normal "central" chi-square for comparison when lambda->0
// w.var("kk")->setVal(4.); // test a large kk
RooDataSet *ncdata = w.pdf("nc")->generate(*w.var("x"), 100);
RooDataSet *csdata = w.pdf("cs")->generate(*w.var("x"), 100);
RooPlot *plot = w.var("x")->frame();
ncdata->plotOn(plot, MarkerColor(kRed));
csdata->plotOn(plot, MarkerColor(kBlue));
w.pdf("nc")->plotOn(plot, LineColor(kRed));
w.pdf("ncc")->plotOn(plot, LineColor(kGreen));
w.pdf("nccc")->plotOn(plot, LineColor(kYellow), LineStyle(kDashed));
w.pdf("cs")->plotOn(plot, LineColor(kBlue), LineStyle(kDotted));
@ kRed
Definition Rtypes.h:66
@ kGreen
Definition Rtypes.h:66
@ kBlue
Definition Rtypes.h:66
@ kYellow
Definition Rtypes.h:66
@ kDashed
Definition TAttLine.h:48
@ kDotted
Definition TAttLine.h:48
virtual RooPlot * plotOn(RooPlot *frame, const RooCmdArg &arg1=RooCmdArg::none(), const RooCmdArg &arg2=RooCmdArg::none(), const RooCmdArg &arg3=RooCmdArg::none(), const RooCmdArg &arg4=RooCmdArg::none(), const RooCmdArg &arg5=RooCmdArg::none(), const RooCmdArg &arg6=RooCmdArg::none(), const RooCmdArg &arg7=RooCmdArg::none(), const RooCmdArg &arg8=RooCmdArg::none()) const
RooDataSet is a container class to hold unbinned data.
Definition RooDataSet.h:33
The PDF of the Non-Central Chi Square distribution for n degrees of freedom.
A RooPlot is a plot frame and a container for graphics objects within that frame.
Definition RooPlot.h:44
static RooPlot * frame(const RooAbsRealLValue &var, Double_t xmin, Double_t xmax, Int_t nBins)
Create a new frame for a given variable in x.
Definition RooPlot.cxx:249
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition RooPlot.cxx:691
The RooWorkspace is a persistable container for RooFit projects.
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
Lorenzo Moneta

Definition in file TestNonCentral.C.