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rf104_classfactory.C
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1/// \file
2/// \ingroup tutorial_roofit
3/// \notebook -js
4///
5/// Basic functionality: The class factory for functions and p.d.f.s
6///
7/// NOTE: This demo uses code that is generated by the macro,
8/// therefore it cannot be compiled in one step by ACliC.
9/// To run this macro compiled with ACliC do
10///
11/// ~~~ {.cpp}
12/// root>.x rf104_classfactory.C // run interpreted to generate code
13/// root>.L MyPdfV3.cxx+ // Compile and load created class
14/// root>.x rf104_classfactory.C+ // run compiled code
15/// ~~~
16///
17/// \macro_image
18/// \macro_output
19/// \macro_code
20///
21/// \date 07/2008
22/// \author Wouter Verkerke
23
24#include "RooRealVar.h"
25#include "RooDataSet.h"
26#include "RooGaussian.h"
27#include "TCanvas.h"
28#include "TAxis.h"
29#include "RooPlot.h"
30#include "RooClassFactory.h"
31#include "TROOT.h"
32
33using namespace RooFit;
34
36{
37 // W r i t e c l a s s s k e l e t o n c o d e
38 // --------------------------------------------------
39
40 // Write skeleton p.d.f class with variable x,a,b
41 // To use this class,
42 // - Edit the file MyPdfV1.cxx and implement the evaluate() method in terms of x,a and b
43 // - Compile and link class with '.x MyPdfV1.cxx+'
44 //
45 RooClassFactory::makePdf("MyPdfV1", "x,A,B");
46
47 // W i t h a d d e d i n i t i a l v a l u e e x p r e s s i o n
48 // ---------------------------------------------------------------------
49
50 // Write skeleton p.d.f class with variable x,a,b and given formula expression
51 // To use this class,
52 // - Compile and link class with '.x MyPdfV2.cxx+'
53 //
54 RooClassFactory::makePdf("MyPdfV2", "x,A,B", "", "A*fabs(x)+pow(x-B,2)");
55
56 // W i t h a d d e d a n a l y t i c a l i n t e g r a l e x p r e s s i o n
57 // ---------------------------------------------------------------------------------
58
59 // Write skeleton p.d.f class with variable x,a,b, given formula expression _and_
60 // given expression for analytical integral over x
61 // To use this class,
62 // - Compile and link class with '.x MyPdfV3.cxx+'
63 //
64 RooClassFactory::makePdf("MyPdfV3", "x,A,B", "", "A*fabs(x)+pow(x-B,2)", kTRUE, kFALSE,
65 "x:(A/2)*(pow(x.max(rangeName),2)+pow(x.min(rangeName),2))+(1./"
66 "3)*(pow(x.max(rangeName)-B,3)-pow(x.min(rangeName)-B,3))");
67
68 // U s e i n s t a n c e o f c r e a t e d c l a s s
69 // ---------------------------------------------------------
70
71 // Compile MyPdfV3 class
72 gROOT->ProcessLineSync(".x MyPdfV3.cxx+");
73
74 // Create instance of MyPdfV3 class
75 RooRealVar a("a", "a", 1);
76 RooRealVar b("b", "b", 2, -10, 10);
77 RooRealVar y("y", "y", -10, 10);
78
79 // We need to hide the type to run in a ROOT macro
80 RooWorkspace w("w");
81 w.factory("MyPdfV3::pdf(y[-10,10], a[1], b[2,-10,10])");
82 auto pdf = w.pdf("pdf");
83
84 // Generate toy data from pdf and plot data and p.d.f on frame
85 RooPlot *frame1 = y.frame(Title("Compiled class MyPdfV3"));
86 RooDataSet *data = pdf->generate(y, 1000);
87 pdf->fitTo(*data);
88 data->plotOn(frame1);
89 pdf->plotOn(frame1);
90
91 // -----------------------------------------------------------------
92 // C o m p i l e d v e r s i o n o f e x a m p l e r f 1 0 3
93 // =================================================================
94
95 // Declare observable x
96 RooRealVar x("x", "x", -20, 20);
97
98 // The RooClassFactory::makePdfInstance() function performs code writing, compiling, linking
99 // and object instantiation in one go and can serve as a straight replacement of RooGenericPdf
100
101 RooRealVar alpha("alpha", "alpha", 5, 0.1, 10);
102 RooAbsPdf *genpdf =
103 RooClassFactory::makePdfInstance("GenPdf", "(1+0.1*fabs(x)+sin(sqrt(fabs(x*alpha+0.1))))", RooArgSet(x, alpha));
104
105 // Generate a toy dataset from the interpreted p.d.f
106 RooDataSet *data2 = genpdf->generate(x, 50000);
107
108 // Fit the interpreted p.d.f to the generated data
109 genpdf->fitTo(*data2);
110
111 // Make a plot of the data and the p.d.f overlaid
112 RooPlot *frame2 = x.frame(Title("Compiled version of pdf of rf103"));
113 data2->plotOn(frame2);
114 genpdf->plotOn(frame2);
115
116 // Draw all frames on a canvas
117 TCanvas *c = new TCanvas("rf104_classfactory", "rf104_classfactory", 800, 400);
118 c->Divide(2);
119 c->cd(1);
120 gPad->SetLeftMargin(0.15);
121 frame1->GetYaxis()->SetTitleOffset(1.4);
122 frame1->Draw();
123 c->cd(2);
124 gPad->SetLeftMargin(0.15);
125 frame2->GetYaxis()->SetTitleOffset(1.4);
126 frame2->Draw();
127}
#define b(i)
Definition: RSha256.hxx:100
#define c(i)
Definition: RSha256.hxx:101
const Bool_t kFALSE
Definition: RtypesCore.h:90
const Bool_t kTRUE
Definition: RtypesCore.h:89
#define gROOT
Definition: TROOT.h:406
#define gPad
Definition: TVirtualPad.h:287
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
Calls RooPlot* plotOn(RooPlot* frame, const RooLinkedList& cmdList) const ;.
Definition: RooAbsData.cxx:546
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
virtual RooFitResult * fitTo(RooAbsData &data, 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())
Fit PDF to given dataset.
Definition: RooAbsPdf.cxx:1254
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 RooCmdArg &arg9=RooCmdArg::none(), const RooCmdArg &arg10=RooCmdArg::none()) const
Helper calling plotOn(RooPlot*, RooLinkedList&) const.
Definition: RooAbsPdf.h:118
RooArgSet is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgSet.h:28
static RooAbsPdf * makePdfInstance(const char *className, const char *name, const char *expression, const RooArgList &vars, const char *intExpression=0)
Write, compile and load code and instantiate object for a RooAbsPdf implementation with class name 'n...
static Bool_t makePdf(const char *name, const char *realArgNames=0, const char *catArgNames=0, const char *expression="1.0", Bool_t hasAnaInt=kFALSE, Bool_t hasIntGen=kFALSE, const char *intExpression=0)
Write code for a RooAbsPdf implementation with class name 'name', taking RooAbsReal arguments with na...
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:33
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:1277
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:712
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:35
The RooWorkspace is a persistable container for RooFit projects.
Definition: RooWorkspace.h:43
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:294
The Canvas class.
Definition: TCanvas.h:27
Double_t y[n]
Definition: legend1.C:17
Double_t x[n]
Definition: legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
const char * Title
Definition: TXMLSetup.cxx:67
auto * a
Definition: textangle.C:12