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Reference Guide
rf505_asciicfg.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook -nodraw
4 /// 'ORGANIZATION AND SIMULTANEOUS FITS' RooFit tutorial macro #505
5 ///
6 /// Reading and writing ASCII configuration files
7 ///
8 /// \macro_output
9 /// \macro_code
10 /// \author 07/2008 - Wouter Verkerke
11 
12 
13 #include "RooRealVar.h"
14 #include "RooDataSet.h"
15 #include "RooGaussian.h"
16 #include "RooConstVar.h"
17 #include "RooPolynomial.h"
18 #include "RooAddPdf.h"
19 #include "TCanvas.h"
20 #include "TAxis.h"
21 #include "RooPlot.h"
22 using namespace RooFit ;
23 
24 
25 void rf505_asciicfg()
26 {
27  // C r e a t e p d f
28  // ------------------
29 
30  // Construct gauss(x,m,s)
31  RooRealVar x("x","x",-10,10) ;
32  RooRealVar m("m","m",0,-10,10) ;
33  RooRealVar s("s","s",1,-10,10) ;
34  RooGaussian gauss("g","g",x,m,s) ;
35 
36  // Construct poly(x,p0)
37  RooRealVar p0("p0","p0",0.01,0.,1.) ;
38  RooPolynomial poly("p","p",x,p0) ;
39 
40  // Construct model = f*gauss(x) + (1-f)*poly(x)
41  RooRealVar f("f","f",0.5,0.,1.) ;
42  RooAddPdf model("model","model",RooArgSet(gauss,poly),f) ;
43 
44 
45 
46  // F i t m o d e l t o t o y d a t a
47  // -----------------------------------------
48 
49  RooDataSet* d = model.generate(x,1000) ;
50  model.fitTo(*d) ;
51 
52 
53  // W r i t e p a r a m e t e r s t o a s c i i f i l e
54  // -----------------------------------------------------------
55 
56  // Obtain set of parameters
57  RooArgSet* params = model.getParameters(x) ;
58 
59  // Write parameters to file
60  params->writeToFile("rf505_asciicfg_example.txt") ;
61 
62 
63  TString dir1 = gROOT->GetTutorialDir() ;
64  dir1.Append("/roofit/rf505_asciicfg.txt") ;
65  TString dir2 = gROOT->GetTutorialDir() ;
66  dir2.Append("/roofit/rf505_asciicfg_example.txt") ;
67  // R e a d p a r a m e t e r s f r o m a s c i i f i l e
68  // ----------------------------------------------------------------
69 
70  // Read parameters from file
71  params->readFromFile(dir2) ;
72  params->Print("v") ;
73 
74  // Read parameters from section 'Section2' of file
75  params->readFromFile(dir1,0,"Section2") ;
76  params->Print("v") ;
77 
78  // Read parameters from section 'Section3' of file. Mark all
79  // variables that were processed with the "READ" attribute
80  params->readFromFile(dir1,"READ","Section3") ;
81 
82  // Print the list of parameters that were not read from Section3
83  cout << "The following parameters of the were _not_ read from Section3: "
84  << (*params->selectByAttrib("READ",kFALSE)) << endl ;
85 
86 
87  // Read parameters from section 'Section4' of file, which contains
88  // 'include file' statement of rf505_asciicfg_example.txt
89  // so that we effective read the same
90 
91  params->readFromFile(dir1,0,"Section4") ;
92  params->Print("v") ;
93 
94 
95 
96 }
RooAddPdf is an efficient implementation of a sum of PDFs of the form.
Definition: RooAddPdf.h:29
#define gROOT
Definition: TROOT.h:375
Double_t x[n]
Definition: legend1.C:17
Plain Gaussian p.d.f.
Definition: RooGaussian.h:25
RooAbsCollection * selectByAttrib(const char *name, Bool_t value) const
Create a subset of the current collection, consisting only of those elements with the specified attri...
virtual void Print(Option_t *options=0) const
This method must be overridden when a class wants to print itself.
RooRealVar represents a fundamental (non-derived) real valued object.
Definition: RooRealVar.h:36
void writeToFile(const char *fileName) const
Write contents of the argset to specified file.
Definition: RooArgSet.cxx:699
TMarker * m
Definition: textangle.C:8
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:29
const Bool_t kFALSE
Definition: RtypesCore.h:92
Bool_t readFromFile(const char *fileName, const char *flagReadAtt=0, const char *section=0, Bool_t verbose=kFALSE)
Read contents of the argset from specified file.
Definition: RooArgSet.cxx:715
double f(double x)
RooPolynomial implements a polynomial p.d.f of the form By default coefficient a_0 is chosen to be 1...
Definition: RooPolynomial.h:28