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rf511_wsfactory_basic.C
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1 /// \file
2 /// \ingroup tutorial_roofit
3 /// \notebook -nodraw
4 ///
5 /// Organization and simultaneous fits: basic use of the 'object factory' associated with
6 /// a workspace to rapidly build p.d.f.s functions and their parameter components
7 ///
8 /// \macro_output
9 /// \macro_code
10 ///
11 /// \date 04/2009
12 /// \author Wouter Verkerke
13 
14 #include "RooRealVar.h"
15 #include "RooDataSet.h"
16 #include "RooGaussian.h"
17 #include "RooConstVar.h"
18 #include "RooChebychev.h"
19 #include "RooAddPdf.h"
20 #include "RooWorkspace.h"
21 #include "RooPlot.h"
22 #include "TCanvas.h"
23 #include "TAxis.h"
24 using namespace RooFit;
25 
26 void rf511_wsfactory_basic(Bool_t compact = kFALSE)
27 {
28  RooWorkspace *w = new RooWorkspace("w");
29 
30  // C r e a t i n g a n d a d d i n g b a s i c p . d . f . s
31  // ----------------------------------------------------------------
32 
33  // Remake example p.d.f. of tutorial rs502_wspacewrite.C:
34  //
35  // Basic p.d.f. construction: ClassName::ObjectName(constructor arguments)
36  // Variable construction : VarName[x,xlo,xhi], VarName[xlo,xhi], VarName[x]
37  // P.d.f. addition : SUM::ObjectName(coef1*pdf1,...coefM*pdfM,pdfN)
38  //
39 
40  if (!compact) {
41 
42  // Use object factory to build p.d.f. of tutorial rs502_wspacewrite
43  w->factory("Gaussian::sig1(x[-10,10],mean[5,0,10],0.5)");
44  w->factory("Gaussian::sig2(x,mean,1)");
45  w->factory("Chebychev::bkg(x,{a0[0.5,0.,1],a1[0.2,0.,1.]})");
46  w->factory("SUM::sig(sig1frac[0.8,0.,1.]*sig1,sig2)");
47  w->factory("SUM::model(bkgfrac[0.5,0.,1.]*bkg,sig)");
48 
49  } else {
50 
51  // Use object factory to build p.d.f. of tutorial rs502_wspacewrite but
52  // - Contracted to a single line recursive expression,
53  // - Omitting explicit names for components that are not referred to explicitly later
54 
55  w->factory("SUM::model(bkgfrac[0.5,0.,1.]*Chebychev::bkg(x[-10,10],{a0[0.5,0.,1],a1[0.2,0.,1.]}),"
56  "SUM(sig1frac[0.8,0.,1.]*Gaussian(x,mean[5,0,10],0.5), Gaussian(x,mean,1)))");
57  }
58 
59  // A d v a n c e d p . d . f . c o n s t r u c t o r a r g u m e n t s
60  // ----------------------------------------------------------------
61  //
62  // P.d.f. constructor arguments may by any type of RooAbsArg, but also
63  //
64  // Double_t --> converted to RooConst(...)
65  // {a,b,c} --> converted to RooArgSet() or RooArgList() depending on required ctor arg
66  // dataset name --> converted to RooAbsData reference for any dataset residing in the workspace
67  // enum --> Any enum label that belongs to an enum defined in the (base) class
68 
69  // Make a dummy dataset p.d.f. 'model' and import it in the workspace
70  RooDataSet *data = w->pdf("model")->generate(*w->var("x"), 1000);
71  w->import(*data, Rename("data"));
72 
73  // Construct a KEYS p.d.f. passing a dataset name and an enum type defining the
74  // mirroring strategy
75  w->factory("KeysPdf::k(x,data,NoMirror,0.2)");
76 
77  // Print workspace contents
78  w->Print();
79 }
RooWorkspace.h
RooChebychev.h
RooGaussian.h
RooAddPdf.h
rf511_wsfactory_basic
Definition: rf511_wsfactory_basic.py:1
TCanvas.h
RooDataSet.h
bool
RooWorkspace::factory
RooFactoryWSTool & factory()
Return instance to factory tool.
Definition: RooWorkspace.cxx:2166
RooWorkspace::import
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.
Definition: RooWorkspace.cxx:361
RooFit::Rename
RooCmdArg Rename(const char *suffix)
Definition: RooGlobalFunc.cxx:315
RooWorkspace::Print
void Print(Option_t *opts=0) const
Print contents of the workspace.
Definition: RooWorkspace.cxx:2194
RooFit
Definition: RooCFunction1Binding.h:29
kFALSE
const Bool_t kFALSE
Definition: RtypesCore.h:92
RooPlot.h
RooWorkspace::pdf
RooAbsPdf * pdf(const char *name) const
Retrieve p.d.f (RooAbsPdf) with given name. A null pointer is returned if not found.
Definition: RooWorkspace.cxx:1277
RooRealVar.h
RooConstVar.h
RooWorkspace
Definition: RooWorkspace.h:43
RooAbsPdf::generate
RooDataSet * generate(const RooArgSet &whatVars, Int_t nEvents, const RooCmdArg &arg1, const RooCmdArg &arg2=RooCmdArg::none(), const RooCmdArg &arg3=RooCmdArg::none(), const RooCmdArg &arg4=RooCmdArg::none(), const RooCmdArg &arg5=RooCmdArg::none())
See RooAbsPdf::generate(const RooArgSet&,const RooCmdArg&,const RooCmdArg&,const RooCmdArg&,...
Definition: RooAbsPdf.h:55
TAxis.h
RooWorkspace::var
RooRealVar * var(const char *name) const
Retrieve real-valued variable (RooRealVar) with given name. A null pointer is returned if not found.
Definition: RooWorkspace.cxx:1295
RooDataSet
Definition: RooDataSet.h:33