ROOT   Reference Guide
rf313_paramranges.C
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1/// \file
2/// \ingroup tutorial_roofit
3/// \notebook -js
4///
5/// Multidimensional models: working with parametrized ranges to define non-rectangular
6/// regions for fitting and integration
7///
8/// \macro_image
9/// \macro_output
10/// \macro_code
11///
12/// \date 07/2008
13/// \author Wouter Verkerke
14
15#include "RooRealVar.h"
16#include "RooDataSet.h"
17#include "RooGaussian.h"
18#include "RooConstVar.h"
19#include "RooPolynomial.h"
20#include "RooProdPdf.h"
21#include "TCanvas.h"
22#include "TAxis.h"
23#include "RooPlot.h"
24using namespace RooFit;
25
27{
28
29 // C r e a t e 3 D p d f
30 // -------------------------
31
32 // Define observable (x,y,z)
33 RooRealVar x("x", "x", 0, 10);
34 RooRealVar y("y", "y", 0, 10);
35 RooRealVar z("z", "z", 0, 10);
36
37 // Define 3 dimensional pdf
38 RooRealVar z0("z0", "z0", -0.1, 1);
39 RooPolynomial px("px", "px", x, RooConst(0));
40 RooPolynomial py("py", "py", y, RooConst(0));
41 RooPolynomial pz("pz", "pz", z, z0);
42 RooProdPdf pxyz("pxyz", "pxyz", RooArgSet(px, py, pz));
43
44 // D e f i n e d n o n - r e c t a n g u l a r r e g i o n R i n ( x , y , z )
45 // -------------------------------------------------------------------------------------
46
47 //
48 // R = Z[0 - 0.1*Y^2] * Y[0.1*X - 0.9*X] * X[0 - 10]
49 //
50
51 // Construct range parametrized in "R" in y [ 0.1*x, 0.9*x ]
52 RooFormulaVar ylo("ylo", "0.1*x", x);
53 RooFormulaVar yhi("yhi", "0.9*x", x);
54 y.setRange("R", ylo, yhi);
55
56 // Construct parametrized ranged "R" in z [ 0, 0.1*y^2 ]
57 RooFormulaVar zlo("zlo", "0.0*y", y);
58 RooFormulaVar zhi("zhi", "0.1*y*y", y);
59 z.setRange("R", zlo, zhi);
60
61 // C a l c u l a t e i n t e g r a l o f n o r m a l i z e d p d f i n R
62 // ----------------------------------------------------------------------------------
63
64 // Create integral over normalized pdf model over x,y,z in "R" region
65 RooAbsReal *intPdf = pxyz.createIntegral(RooArgSet(x, y, z), RooArgSet(x, y, z), "R");
66
67 // Plot value of integral as function of pdf parameter z0
68 RooPlot *frame = z0.frame(Title("Integral of pxyz over x,y,z in region R"));
69 intPdf->plotOn(frame);
70
71 new TCanvas("rf313_paramranges", "rf313_paramranges", 600, 600);
73 frame->GetYaxis()->SetTitleOffset(1.6);
74 frame->Draw();
75
76 return;
77}
RooAbsReal is the common abstract base class for objects that represent a real value and implements f...
Definition: RooAbsReal.h:60
virtual RooPlot * plotOn(RooPlot *frame, 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(), const RooCmdArg &arg10=RooCmdArg()) const
Plot (project) PDF on specified frame.
RooAbsReal * createIntegral(const RooArgSet &iset, const RooCmdArg &arg1, 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
Create an object that represents the integral of the function over one or more observables listed in ...
Definition: RooAbsReal.cxx:560
RooArgSet is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgSet.h:28
A RooFormulaVar is a generic implementation of a real-valued object, which takes a RooArgList of serv...
Definition: RooFormulaVar.h:29
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
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:277
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:712
RooPolynomial implements a polynomial p.d.f of the form.
Definition: RooPolynomial.h:28
RooProdPdf is an efficient implementation of a product of PDFs of the form.
Definition: RooProdPdf.h:31
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:35
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
RooConstVar & RooConst(Double_t val)
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