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rf207_comptools.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook -nodraw
4 ///
5 /// Addition and convolution: tools and utilities for manipulation of composite objects
6 ///
7 /// \macro_output
8 /// \macro_code
9 ///
10 /// \date 07/2008
11 /// \author Wouter Verkerke
12 
13 #include "RooRealVar.h"
14 #include "RooDataSet.h"
15 #include "RooGaussian.h"
16 #include "RooChebychev.h"
17 #include "RooExponential.h"
18 #include "RooAddPdf.h"
19 #include "RooPlot.h"
20 #include "RooCustomizer.h"
21 #include "TCanvas.h"
22 #include "TAxis.h"
23 #include "TH1.h"
24 using namespace RooFit;
25 
26 void rf207_comptools()
27 {
28 
29  // S e t u p c o m p o s i t e p d f, d a t a s e t
30  // --------------------------------------------------------
31 
32  // Declare observable x
33  RooRealVar x("x", "x", 0, 10);
34 
35  // Create two Gaussian PDFs g1(x,mean1,sigma) anf g2(x,mean2,sigma) and their parameters
36  RooRealVar mean("mean", "mean of gaussians", 5);
37  RooRealVar sigma("sigma", "width of gaussians", 0.5);
38  RooGaussian sig("sig", "Signal component 1", x, mean, sigma);
39 
40  // Build Chebychev polynomial p.d.f.
41  RooRealVar a0("a0", "a0", 0.5, 0., 1.);
42  RooRealVar a1("a1", "a1", 0.2, 0., 1.);
43  RooChebychev bkg1("bkg1", "Background 1", x, RooArgSet(a0, a1));
44 
45  // Build exponential pdf
46  RooRealVar alpha("alpha", "alpha", -1);
47  RooExponential bkg2("bkg2", "Background 2", x, alpha);
48 
49  // Sum the background components into a composite background p.d.f.
50  RooRealVar bkg1frac("bkg1frac", "fraction of component 1 in background", 0.2, 0., 1.);
51  RooAddPdf bkg("bkg", "Signal", RooArgList(bkg1, bkg2), bkg1frac);
52 
53  // Sum the composite signal and background
54  RooRealVar bkgfrac("bkgfrac", "fraction of background", 0.5, 0., 1.);
55  RooAddPdf model("model", "g1+g2+a", RooArgList(bkg, sig), bkgfrac);
56 
57  // Create dummy dataset that has more observables than the above pdf
58  RooRealVar y("y", "y", -10, 10);
59  RooDataSet data("data", "data", RooArgSet(x, y));
60 
61  // ---------------------------------------------------
62  // B a s i c i n f o r m a t i o n r e q u e s t s
63  // ===================================================
64 
65  // G e t l i s t o f o b s e r v a b l e s
66  // ---------------------------------------------
67 
68  // Get list of observables of pdf in context of a dataset
69  //
70  // Observables are define each context as the variables
71  // shared between a model and a dataset. In this case
72  // that is the variable 'x'
73 
74  RooArgSet *model_obs = model.getObservables(data);
75  model_obs->Print("v");
76 
77  // G e t l i s t o f p a r a m e t e r s
78  // -------------------------------------------
79 
80  // Get list of parameters, given list of observables
81  RooArgSet *model_params = model.getParameters(x);
82  model_params->Print("v");
83 
84  // Get list of parameters, given a dataset
85  // (Gives identical results to operation above)
86  RooArgSet *model_params2 = model.getParameters(data);
87  model_params2->Print();
88 
89  // G e t l i s t o f c o m p o n e n t s
90  // -------------------------------------------
91 
92  // Get list of component objects, including top-level node
93  RooArgSet *model_comps = model.getComponents();
94  model_comps->Print("v");
95 
96  // -------------------------------------------------------------------------------
97  // M o d i f i c a t i o n s t o s t r u c t u r e o f c o m p o s i t e s
98  // ===============================================================================
99 
100  // Create a second Gaussian
101  RooRealVar sigma2("sigma2", "width of gaussians", 1);
102  RooGaussian sig2("sig2", "Signal component 1", x, mean, sigma2);
103 
104  // Create a sum of the original Gaussian plus the new second Gaussian
105  RooRealVar sig1frac("sig1frac", "fraction of component 1 in signal", 0.8, 0., 1.);
106  RooAddPdf sigsum("sigsum", "sig+sig2", RooArgList(sig, sig2), sig1frac);
107 
108  // Construct a customizer utility to customize model
109  RooCustomizer cust(model, "cust");
110 
111  // Instruct the customizer to replace node 'sig' with node 'sigsum'
112  cust.replaceArg(sig, sigsum);
113 
114  // Build a clone of the input pdf according to the above customization
115  // instructions. Each node that requires modified is clone so that the
116  // original pdf remained untouched. The name of each cloned node is that
117  // of the original node suffixed by the name of the customizer object
118  //
119  // The returned head node own all nodes that were cloned as part of
120  // the build process so when cust_clone is deleted so will all other
121  // nodes that were created in the process.
122  RooAbsPdf *cust_clone = (RooAbsPdf *)cust.build(kTRUE);
123 
124  // Print structure of clone of model with sig->sigsum replacement.
125  cust_clone->Print("t");
126 
127  delete cust_clone;
128 }
kTRUE
const Bool_t kTRUE
Definition: RtypesCore.h:91
RooChebychev.h
RooAddPdf
Definition: RooAddPdf.h:32
RooChebychev
Definition: RooChebychev.h:25
RooCustomizer
Definition: RooCustomizer.h:35
RooAbsArg::Print
virtual void Print(Option_t *options=0) const
Print the object to the defaultPrintStream().
Definition: RooAbsArg.h:320
RooArgList
Definition: RooArgList.h:21
RooGaussian.h
x
Double_t x[n]
Definition: legend1.C:17
RooGaussian
Definition: RooGaussian.h:25
RooAddPdf.h
TCanvas.h
RooDataSet.h
RooCustomizer.h
RooFit
Definition: RooCFunction1Binding.h:29
RooPlot.h
y
Double_t y[n]
Definition: legend1.C:17
RooRealVar.h
RooExponential.h
sigma
const Double_t sigma
Definition: h1analysisProxy.h:11
TAxis.h
RooDataSet
Definition: RooDataSet.h:33
make_cnn_model.model
model
Definition: make_cnn_model.py:6
RooAbsCollection::Print
virtual void Print(Option_t *options=0) const
This method must be overridden when a class wants to print itself.
Definition: RooAbsCollection.h:199
RooAbsPdf
Definition: RooAbsPdf.h:40
RooRealVar
Definition: RooRealVar.h:35
RooExponential
Definition: RooExponential.h:25
TH1.h
RooArgSet
Definition: RooArgSet.h:28