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Reference Guide
rf509_wsinteractive.C
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1/// \file
2/// \ingroup tutorial_roofit
3/// \notebook -js
4/// Organization and simultaneous fits: easy interactive access to workspace contents - CINT
5/// to CLING code migration
6///
7/// \macro_image
8/// \macro_output
9/// \macro_code
10///
11/// \date April 2009
12/// \author Wouter Verkerke
13
14using namespace RooFit;
15
16void fillWorkspace(RooWorkspace &w);
17
19{
20 // C r e a t e a n d f i l l w o r k s p a c e
21 // ------------------------------------------------
22
23 // Create a workspace named 'w'
24 // With CINT w could exports its contents to
25 // a same-name C++ namespace in CINT 'namespace w'.
26 // but this does not work anymore in CLING.
27 // so this tutorial is an example on how to
28 // change the code
29 RooWorkspace *w1 = new RooWorkspace("w", kTRUE);
30
31 // Fill workspace with pdf and data in a separate function
32 fillWorkspace(*w1);
33
34 // Print workspace contents
35 w1->Print();
36
37 // this does not work anymore with CLING
38 // use normal workspace functionality
39
40 // U s e w o r k s p a c e c o n t e n t s
41 // ----------------------------------------------
42
43 // Old syntax to use the name space prefix operator to access the workspace contents
44 //
45 // RooDataSet* d = w::model.generate(w::x,1000) ;
46 // RooFitResult* r = w::model.fitTo(*d) ;
47
48 // use normal workspace methods
49 RooAbsPdf *model = w1->pdf("model");
50 RooRealVar *x = w1->var("x");
51
52 RooDataSet *d = model->generate(*x, 1000);
53 RooFitResult *r = model->fitTo(*d);
54
55 // old syntax to access the variable x
56 // RooPlot* frame = w::x.frame() ;
57
58 RooPlot *frame = x->frame();
59 d->plotOn(frame);
60
61 // OLD syntax to omit x::
62 // NB: The 'w::' prefix can be omitted if namespace w is imported in local namespace
63 // in the usual C++ way
64 //
65 // using namespace w;
66 // model.plotOn(frame) ;
67 // model.plotOn(frame,Components(bkg),LineStyle(kDashed)) ;
68
69 // new correct syntax
70 RooAbsPdf *bkg = w1->pdf("bkg");
71 model->plotOn(frame);
72 model->plotOn(frame, Components(*bkg), LineStyle(kDashed));
73
74 // Draw the frame on the canvas
75 new TCanvas("rf509_wsinteractive", "rf509_wsinteractive", 600, 600);
76 gPad->SetLeftMargin(0.15);
77 frame->GetYaxis()->SetTitleOffset(1.4);
78 frame->Draw();
79}
80
81void fillWorkspace(RooWorkspace &w)
82{
83 // C r e a t e p d f a n d f i l l w o r k s p a c e
84 // --------------------------------------------------------
85
86 // Declare observable x
87 RooRealVar x("x", "x", 0, 10);
88
89 // Create two Gaussian PDFs g1(x,mean1,sigma) anf g2(x,mean2,sigma) and their parameters
90 RooRealVar mean("mean", "mean of gaussians", 5, 0, 10);
91 RooRealVar sigma1("sigma1", "width of gaussians", 0.5);
92 RooRealVar sigma2("sigma2", "width of gaussians", 1);
93
94 RooGaussian sig1("sig1", "Signal component 1", x, mean, sigma1);
95 RooGaussian sig2("sig2", "Signal component 2", x, mean, sigma2);
96
97 // Build Chebychev polynomial pdf
98 RooRealVar a0("a0", "a0", 0.5, 0., 1.);
99 RooRealVar a1("a1", "a1", 0.2, 0., 1.);
100 RooChebychev bkg("bkg", "Background", x, RooArgSet(a0, a1));
101
102 // Sum the signal components into a composite signal pdf
103 RooRealVar sig1frac("sig1frac", "fraction of component 1 in signal", 0.8, 0., 1.);
104 RooAddPdf sig("sig", "Signal", RooArgList(sig1, sig2), sig1frac);
105
106 // Sum the composite signal and background
107 RooRealVar bkgfrac("bkgfrac", "fraction of background", 0.5, 0., 1.);
108 RooAddPdf model("model", "g1+g2+a", RooArgList(bkg, sig), bkgfrac);
109
110 w.import(model);
111}
ROOT::R::TRInterface & r
Definition: Object.C:4
#define d(i)
Definition: RSha256.hxx:102
const Bool_t kTRUE
Definition: RtypesCore.h:91
@ kDashed
Definition: TAttLine.h:48
#define gPad
Definition: TVirtualPad.h:287
RooAddPdf is an efficient implementation of a sum of PDFs of the form.
Definition: RooAddPdf.h:32
RooArgList is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgList.h:21
RooArgSet is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgSet.h:29
Chebychev polynomial p.d.f.
Definition: RooChebychev.h:25
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:33
RooFitResult is a container class to hold the input and output of a PDF fit to a dataset.
Definition: RooFitResult.h:40
Plain Gaussian p.d.f.
Definition: RooGaussian.h:24
A RooPlot is a plot frame and a container for graphics objects within that frame.
Definition: RooPlot.h:44
TAxis * GetYaxis() const
Definition: RooPlot.cxx:1263
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:691
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:39
The RooWorkspace is a persistable container for RooFit projects.
Definition: RooWorkspace.h:43
void Print(Option_t *opts=0) const
Print contents of the workspace.
RooRealVar * var(const char *name) const
Retrieve real-valued variable (RooRealVar) with given name. A null pointer is returned if not found.
Bool_t import(const RooAbsArg &arg, const RooCmdArg &arg1=RooCmdArg(), const RooCmdArg &arg2=RooCmdArg(), const RooCmdArg &arg3=RooCmdArg(), const RooCmdArg &arg4=RooCmdArg(), const RooCmdArg &arg5=RooCmdArg(), const RooCmdArg &arg6=RooCmdArg(), const RooCmdArg &arg7=RooCmdArg(), const RooCmdArg &arg8=RooCmdArg(), const RooCmdArg &arg9=RooCmdArg())
Import a RooAbsArg object, e.g.
RooAbsPdf * pdf(const char *name) const
Retrieve p.d.f (RooAbsPdf) with given name. A null pointer is returned if not found.
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:293
The Canvas class.
Definition: TCanvas.h:23
RooCmdArg Components(const RooArgSet &compSet)
RooCmdArg LineStyle(Style_t style)
Double_t x[n]
Definition: legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...