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rf706_histpdf.C File Reference

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Special p.d.f.'s: histogram-based p.d.f.s and functions

RooFit v3.60 -- Developed by Wouter Verkerke and David Kirkby
Copyright (C) 2000-2013 NIKHEF, University of California & Stanford University
All rights reserved, please read http://roofit.sourceforge.net/license.txt
#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "RooConstVar.h"
#include "RooPolynomial.h"
#include "RooHistPdf.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "RooPlot.h"
using namespace RooFit;
{
// C r e a t e p d f f o r s a m p l i n g
// ---------------------------------------------
RooRealVar x("x", "x", 0, 20);
RooPolynomial p("p", "p", x, RooArgList(RooConst(0.01), RooConst(-0.01), RooConst(0.0004)));
// C r e a t e l o w s t a t s h i s t o g r a m
// ---------------------------------------------------
// Sample 500 events from p
x.setBins(20);
RooDataSet *data1 = p.generate(x, 500);
// Create a binned dataset with 20 bins and 500 events
RooDataHist *hist1 = data1->binnedClone();
// Represent data in dh as pdf in x
RooHistPdf histpdf1("histpdf1", "histpdf1", x, *hist1, 0);
// Plot unbinned data and histogram pdf overlaid
RooPlot *frame1 = x.frame(Title("Low statistics histogram pdf"), Bins(100));
data1->plotOn(frame1);
histpdf1.plotOn(frame1);
// C r e a t e h i g h s t a t s h i s t o g r a m
// -----------------------------------------------------
// Sample 100000 events from p
x.setBins(10);
RooDataSet *data2 = p.generate(x, 100000);
// Create a binned dataset with 10 bins and 100K events
RooDataHist *hist2 = data2->binnedClone();
// Represent data in dh as pdf in x, apply 2nd order interpolation
RooHistPdf histpdf2("histpdf2", "histpdf2", x, *hist2, 2);
// Plot unbinned data and histogram pdf overlaid
RooPlot *frame2 = x.frame(Title("High stats histogram pdf with interpolation"), Bins(100));
data2->plotOn(frame2);
histpdf2.plotOn(frame2);
TCanvas *c = new TCanvas("rf706_histpdf", "rf706_histpdf", 800, 400);
c->Divide(2);
c->cd(1);
gPad->SetLeftMargin(0.15);
frame1->GetYaxis()->SetTitleOffset(1.4);
frame1->Draw();
c->cd(2);
gPad->SetLeftMargin(0.15);
frame2->GetYaxis()->SetTitleOffset(1.8);
frame2->Draw();
}
Date
07/2008
Author
Wouter Verkerke

Definition in file rf706_histpdf.C.

c
#define c(i)
Definition: RSha256.hxx:119
RooPlot::Draw
virtual void Draw(Option_t *options=0)
Draw this plot and all of the elements it contains.
Definition: RooPlot.cxx:691
RooFit::Bins
RooCmdArg Bins(Int_t nbin)
Definition: RooGlobalFunc.cxx:174
rf706_histpdf
Definition: rf706_histpdf.py:1
RooArgList
Definition: RooArgList.h:21
RooGaussian.h
x
Double_t x[n]
Definition: legend1.C:17
TCanvas.h
RooDataSet.h
RooPolynomial.h
RooDataHist
Definition: RooDataHist.h:39
RooFit
Definition: RooCFunction1Binding.h:29
RooPolynomial
Definition: RooPolynomial.h:28
RooAbsData::plotOn
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
Definition: RooAbsData.cxx:547
RooPlot.h
RooPlot::GetYaxis
TAxis * GetYaxis() const
Definition: RooPlot.cxx:1256
RooPlot
Definition: RooPlot.h:44
RooRealVar.h
RooHistPdf
Definition: RooHistPdf.h:29
RooConstVar.h
RooHistPdf.h
TCanvas
Definition: TCanvas.h:23
TAxis.h
RooDataSet::binnedClone
RooDataHist * binnedClone(const char *newName=0, const char *newTitle=0) const
Return binned clone of this dataset.
Definition: RooDataSet.cxx:972
gPad
#define gPad
Definition: TVirtualPad.h:287
RooDataSet
Definition: RooDataSet.h:33
TAttAxis::SetTitleOffset
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition: TAttAxis.cxx:293
RooRealVar
Definition: RooRealVar.h:35
RooFit::Title
RooCmdArg Title(const char *name)
Definition: RooGlobalFunc.cxx:173
RooFit::RooConst
RooConstVar & RooConst(Double_t val)
Definition: RooGlobalFunc.cxx:341