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TestNonCentral.C File Reference

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[#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()
{
// k <2, must use sum
w.factory("NonCentralChiSquare::nc(x[0,50],k[1.99,0,5],lambda[5])");
// kk > 2 can use bessel
w.factory("NonCentralChiSquare::ncc(x,kk[2.01,0,5],lambda)");
// kk > 2, force sum
w.factory("NonCentralChiSquare::nccc(x,kk,lambda)");
((RooNonCentralChiSquare *)w.pdf("nccc"))->SetForceSum(true);
// a normal "central" chi-square for comparison when lambda->0
w.factory("ChiSquarePdf::cs(x,k)");
// w.var("kk")->setVal(4.); // test a large kk
std::unique_ptr<RooDataSet> ncdata{w.pdf("nc")->generate(*w.var("x"), 100)};
std::unique_ptr<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));
plot->Draw();
}
@ 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
winID h TVirtualViewer3D TVirtualGLPainter char TVirtualGLPainter plot
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:43
Persistable container for RooFit projects.
virtual void Draw(Option_t *option="")
Default Draw method for all objects.
Definition TObject.cxx:274
RooCmdArg MarkerColor(Color_t color)
RooCmdArg LineColor(Color_t color)
RooCmdArg LineStyle(Style_t style)
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
Definition JSONIO.h:26
Author
Lorenzo Moneta

Definition in file TestNonCentral.C.