rf205_compplot.C: 'ADDITION AND CONVOLUTION' RooFit tutorial macro #205
//////////////////////////////////////////////////////////////////////////
//
// 'ADDITION AND CONVOLUTION' RooFit tutorial macro #205
//
// Options for plotting components of composite p.d.f.s.
//
//
//
// 07/2008 - Wouter Verkerke
//
/////////////////////////////////////////////////////////////////////////
#ifndef __CINT__
#include "RooGlobalFunc.h"
#endif
#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "RooAddPdf.h"
#include "RooChebychev.h"
#include "RooExponential.h"
#include "TCanvas.h"
#include "RooPlot.h"
using namespace RooFit ;
void rf205_compplot()
{
// S e t u p c o m p o s i t e p d f
// --------------------------------------
// Declare observable x
RooRealVar x("x","x",0,10) ;
// Create two Gaussian PDFs g1(x,mean1,sigma) anf g2(x,mean2,sigma) and their paramaters
RooRealVar mean("mean","mean of gaussians",5) ;
RooRealVar sigma1("sigma1","width of gaussians",0.5) ;
RooRealVar sigma2("sigma2","width of gaussians",1) ;
RooGaussian sig1("sig1","Signal component 1",x,mean,sigma1) ;
RooGaussian sig2("sig2","Signal component 2",x,mean,sigma2) ;
// Sum the signal components into a composite signal p.d.f.
RooRealVar sig1frac("sig1frac","fraction of component 1 in signal",0.8,0.,1.) ;
RooAddPdf sig("sig","Signal",RooArgList(sig1,sig2),sig1frac) ;
// Build Chebychev polynomial p.d.f.
RooRealVar a0("a0","a0",0.5,0.,1.) ;
RooRealVar a1("a1","a1",-0.2,0.,1.) ;
RooChebychev bkg1("bkg1","Background 1",x,RooArgSet(a0,a1)) ;
// Build expontential pdf
RooRealVar alpha("alpha","alpha",-1) ;
RooExponential bkg2("bkg2","Background 2",x,alpha) ;
// Sum the background components into a composite background p.d.f.
RooRealVar bkg1frac("sig1frac","fraction of component 1 in background",0.2,0.,1.) ;
RooAddPdf bkg("bkg","Signal",RooArgList(bkg1,bkg2),sig1frac) ;
// Sum the composite signal and background
RooRealVar bkgfrac("bkgfrac","fraction of background",0.5,0.,1.) ;
RooAddPdf model("model","g1+g2+a",RooArgList(bkg,sig),bkgfrac) ;
// S e t u p b a s i c p l o t w i t h d a t a a n d f u l l p d f
// ------------------------------------------------------------------------------
// Generate a data sample of 1000 events in x from model
RooDataSet *data = model.generate(x,1000) ;
// Plot data and complete PDF overlaid
RooPlot* xframe = x.frame(Title("Component plotting of pdf=(sig1+sig2)+(bkg1+bkg2)")) ;
data->plotOn(xframe) ;
model.plotOn(xframe) ;
// Clone xframe for use below
RooPlot* xframe2 = (RooPlot*) xframe->Clone("xframe2") ;
// M a k e c o m p o n e n t b y o b j e c t r e f e r e n c e
// --------------------------------------------------------------------
// Plot single background component specified by object reference
model.plotOn(xframe,Components(bkg),LineColor(kRed)) ;
// Plot single background component specified by object reference
model.plotOn(xframe,Components(bkg2),LineStyle(kDashed),LineColor(kRed)) ;
// Plot multiple background components specified by object reference
// Note that specified components may occur at any level in object tree
// (e.g bkg is component of 'model' and 'sig2' is component 'sig')
model.plotOn(xframe,Components(RooArgSet(bkg,sig2)),LineStyle(kDotted)) ;
// M a k e c o m p o n e n t b y n a m e / r e g e x p
// ------------------------------------------------------------
// Plot single background component specified by name
model.plotOn(xframe2,Components("bkg"),LineColor(kCyan)) ;
// Plot multiple background components specified by name
model.plotOn(xframe2,Components("bkg1,sig2"),LineStyle(kDotted),LineColor(kCyan)) ;
// Plot multiple background components specified by regular expression on name
model.plotOn(xframe2,Components("sig*"),LineStyle(kDashed),LineColor(kCyan)) ;
// Plot multiple background components specified by multiple regular expressions on name
model.plotOn(xframe2,Components("bkg1,sig*"),LineStyle(kDashed),LineColor(kYellow),Invisible()) ;
// Draw the frame on the canvas
TCanvas* c = new TCanvas("rf205_compplot","rf205_compplot",800,400) ;
c->Divide(2) ;
c->cd(1) ; xframe->Draw() ;
c->cd(2) ; xframe2->Draw() ;
}
Last change: Wed Dec 17 10:56:33 2008
Last generated: 2008-12-17 10:56
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