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rf307_fullpereventerrors.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook
4 ///
5 /// Multidimensional models: full p.d.f. with per-event errors
6 ///
7 /// \macro_code
8 ///
9 /// \date 07/2008
10 /// \author Wouter Verkerke
11 
12 #include "RooRealVar.h"
13 #include "RooDataSet.h"
14 #include "RooGaussian.h"
15 #include "RooGaussModel.h"
16 #include "RooConstVar.h"
17 #include "RooDecay.h"
18 #include "RooLandau.h"
19 #include "RooProdPdf.h"
20 #include "RooHistPdf.h"
21 #include "RooPlot.h"
22 #include "TCanvas.h"
23 #include "TAxis.h"
24 #include "TH1.h"
25 using namespace RooFit;
26 
28 {
29  // B - p h y s i c s p d f w i t h p e r - e v e n t G a u s s i a n r e s o l u t i o n
30  // ----------------------------------------------------------------------------------------------
31 
32  // Observables
33  RooRealVar dt("dt", "dt", -10, 10);
34  RooRealVar dterr("dterr", "per-event error on dt", 0.01, 10);
35 
36  // Build a gaussian resolution model scaled by the per-event error = gauss(dt,bias,sigma*dterr)
37  RooRealVar bias("bias", "bias", 0, -10, 10);
38  RooRealVar sigma("sigma", "per-event error scale factor", 1, 0.1, 10);
39  RooGaussModel gm("gm1", "gauss model scaled bt per-event error", dt, bias, sigma, dterr);
40 
41  // Construct decay(dt) (x) gauss1(dt|dterr)
42  RooRealVar tau("tau", "tau", 1.548);
43  RooDecay decay_gm("decay_gm", "decay", dt, tau, gm, RooDecay::DoubleSided);
44 
45  // C o n s t r u c t e m p i r i c a l p d f f o r p e r - e v e n t e r r o r
46  // -----------------------------------------------------------------
47 
48  // Use landau p.d.f to get empirical distribution with long tail
49  RooLandau pdfDtErr("pdfDtErr", "pdfDtErr", dterr, RooConst(1), RooConst(0.25));
50  RooDataSet *expDataDterr = pdfDtErr.generate(dterr, 10000);
51 
52  // Construct a histogram pdf to describe the shape of the dtErr distribution
53  RooDataHist *expHistDterr = expDataDterr->binnedClone();
54  RooHistPdf pdfErr("pdfErr", "pdfErr", dterr, *expHistDterr);
55 
56  // C o n s t r u c t c o n d i t i o n a l p r o d u c t d e c a y _ d m ( d t | d t e r r ) * p d f ( d t e r
57  // r )
58  // ----------------------------------------------------------------------------------------------------------------------
59 
60  // Construct production of conditional decay_dm(dt|dterr) with empirical pdfErr(dterr)
61  RooProdPdf model("model", "model", pdfErr, Conditional(decay_gm, dt));
62 
63  // (Alternatively you could also use the landau shape pdfDtErr)
64  // RooProdPdf model("model","model",pdfDtErr,Conditional(decay_gm,dt)) ;
65 
66  // S a m p l e, f i t a n d p l o t p r o d u c t m o d e l
67  // ------------------------------------------------------------------
68 
69  // Specify external dataset with dterr values to use model_dm as conditional p.d.f.
70  RooDataSet *data = model.generate(RooArgSet(dt, dterr), 10000);
71 
72  // F i t c o n d i t i o n a l d e c a y _ d m ( d t | d t e r r )
73  // ---------------------------------------------------------------------
74 
75  // Specify dterr as conditional observable
76  model.fitTo(*data);
77 
78  // P l o t c o n d i t i o n a l d e c a y _ d m ( d t | d t e r r )
79  // ---------------------------------------------------------------------
80 
81  // Make two-dimensional plot of conditional p.d.f in (dt,dterr)
82  TH1 *hh_model = model.createHistogram("hh_model", dt, Binning(50), YVar(dterr, Binning(50)));
83  hh_model->SetLineColor(kBlue);
84 
85  // Make projection of data an dt
86  RooPlot *frame = dt.frame(Title("Projection of model(dt|dterr) on dt"));
87  data->plotOn(frame);
88  model.plotOn(frame);
89 
90  // Draw all frames on canvas
91  TCanvas *c = new TCanvas("rf307_fullpereventerrors", "rf307_fullperventerrors", 800, 400);
92  c->Divide(2);
93  c->cd(1);
94  gPad->SetLeftMargin(0.20);
95  hh_model->GetZaxis()->SetTitleOffset(2.5);
96  hh_model->Draw("surf");
97  c->cd(2);
98  gPad->SetLeftMargin(0.15);
99  frame->GetYaxis()->SetTitleOffset(1.6);
100  frame->Draw();
101 }
c
#define c(i)
Definition: RSha256.hxx:119
RooPlot::Draw
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:691
RooGaussModel.h
RooLandau
Definition: RooLandau.h:24
RooGaussian.h
RooDecay.h
TCanvas.h
RooFit::YVar
RooCmdArg YVar(const RooAbsRealLValue &var, const RooCmdArg &arg=RooCmdArg::none())
Definition: RooGlobalFunc.cxx:240
RooFit::Binning
RooCmdArg Binning(const RooAbsBinning &binning)
Definition: RooGlobalFunc.cxx:82
TH1::GetZaxis
TAxis * GetZaxis()
Definition: TH1.h:319
RooDataSet.h
RooPlot::frame
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
RooDataHist
Definition: RooDataHist.h:39
RooProdPdf.h
RooFit
Definition: RooCFunction1Binding.h:29
RooDecay
Definition: RooDecay.h:22
RooAbsData::plotOn
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
Definition: RooAbsData.cxx:547
RooPlot.h
RooPlot::GetYaxis
TAxis * GetYaxis() const
Definition: RooPlot.cxx:1256
rf307_fullpereventerrors
Definition: rf307_fullpereventerrors.py:1
RooPlot
Definition: RooPlot.h:44
RooRealVar.h
RooHistPdf
Definition: RooHistPdf.h:29
RooConstVar.h
RooHistPdf.h
sigma
const Double_t sigma
Definition: h1analysisProxy.h:11
RooFit::Conditional
RooCmdArg Conditional(const RooArgSet &pdfSet, const RooArgSet &depSet, Bool_t depsAreCond=kFALSE)
Definition: RooGlobalFunc.cxx:225
TCanvas
Definition: TCanvas.h:23
TAxis.h
RooDataSet::binnedClone
RooDataHist * binnedClone(const char *newName=0, const char *newTitle=0) const
Return binned clone of this dataset.
Definition: RooDataSet.cxx:972
TH1
Definition: TH1.h:57
kBlue
@ kBlue
Definition: Rtypes.h:66
gPad
#define gPad
Definition: TVirtualPad.h:287
RooDataSet
Definition: RooDataSet.h:33
make_cnn_model.model
model
Definition: make_cnn_model.py:6
TAttAxis::SetTitleOffset
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:293
RooDecay::DoubleSided
@ DoubleSided
Definition: RooDecay.h:53
RooRealVar
Definition: RooRealVar.h:35
RooGaussModel
Definition: RooGaussModel.h:26
RooProdPdf
Definition: RooProdPdf.h:33
TH1.h
RooFit::Title
RooCmdArg Title(const char *name)
Definition: RooGlobalFunc.cxx:173
RooArgSet
Definition: RooArgSet.h:28
RooLandau.h
TH1::Draw
virtual void Draw(Option_t *option="")
Draw this histogram with options.
Definition: TH1.cxx:2997
RooFit::RooConst
RooConstVar & RooConst(Double_t val)
Definition: RooGlobalFunc.cxx:341