ROOT   Reference Guide
Searching...
No Matches
rf205_compplot.C File Reference

## Detailed Description

Addition and convolution: options for plotting components of composite pdfs.

#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "RooChebychev.h"
#include "RooExponential.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "RooPlot.h"
using namespace RooFit;
{
// 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 parameters
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 pdf
RooRealVar sig1frac("sig1frac", "fraction of component 1 in signal", 0.8, 0., 1.);
RooAddPdf sig("sig", "Signal", {sig1, sig2}, sig1frac);
// Build Chebychev polynomial pdf
RooRealVar a0("a0", "a0", 0.5, 0., 1.);
RooRealVar a1("a1", "a1", 0.2, 0., 1.);
RooChebychev bkg1("bkg1", "Background 1", x, {a0, a1});
// Build exponential pdf
RooRealVar alpha("alpha", "alpha", -1);
RooExponential bkg2("bkg2", "Background 2", x, alpha);
// Sum the background components into a composite background pdf
RooRealVar bkg1frac("bkg1frac", "fraction of component 1 in background", 0.8, 0., 1.);
RooAddPdf bkg("bkg", "Total background", {bkg1, bkg2}, bkg1frac);
// Sum the composite signal and background
RooRealVar bkgfrac("bkgfrac", "fraction of background", 0.5, 0., 1.);
RooAddPdf model("model", "g1+g2+a", {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
std::unique_ptr<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(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->GetYaxis()->SetTitleOffset(1.4);
xframe->Draw();
c->cd(2);
xframe2->GetYaxis()->SetTitleOffset(1.4);
xframe2->Draw();
c->Draw();
}
#define c(i)
Definition RSha256.hxx:101
@ kRed
Definition Rtypes.h:66
@ kCyan
Definition Rtypes.h:66
@ kYellow
Definition Rtypes.h:66
@ kDashed
Definition TAttLine.h:48
@ kDotted
Definition TAttLine.h:48
Option_t Option_t TPoint TPoint const char GetTextMagnitude GetFillStyle GetLineColor GetLineWidth GetMarkerStyle GetTextAlign GetTextColor GetTextSize void data
Efficient implementation of a sum of PDFs of the form.
Chebychev polynomial p.d.f.
Exponential PDF.
Plain Gaussian p.d.f.
Definition RooGaussian.h:24
Plot frame and a container for graphics objects within that frame.
Definition RooPlot.h:43
static RooPlot * frame(const RooAbsRealLValue &var, double xmin, double xmax, Int_t nBins)
Create a new frame for a given variable in x.
Definition RooPlot.cxx:237
TAxis * GetYaxis() const
Definition RooPlot.cxx:1276
void Draw(Option_t *options=nullptr) override
Draw this plot and all of the elements it contains.
Definition RooPlot.cxx:649
Variable that can be changed from the outside.
Definition RooRealVar.h:37
virtual void SetTitleOffset(Float_t offset=1)
Set distance between the axis and the axis title.
Definition TAttAxis.cxx:298
The Canvas class.
Definition TCanvas.h:23
TObject * Clone(const char *newname="") const override
Make a clone of an object using the Streamer facility.
Definition TNamed.cxx:74
RooCmdArg Components(Args_t &&... argsOrArgSet)
RooCmdArg Invisible(bool inv=true)
RooCmdArg LineColor(Color_t color)
RooCmdArg LineStyle(Style_t style)
Double_t x[n]
Definition legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
Definition JSONIO.h:26
const char * Title
Definition TXMLSetup.cxx:68
[#0] WARNING:InputArguments -- The parameter 'sigma1' with range [-inf, inf] of the RooGaussian 'sig1' exceeds the safe range of (0, inf). Advise to limit its range.
[#0] WARNING:InputArguments -- The parameter 'sigma2' with range [-inf, inf] of the RooGaussian 'sig2' exceeds the safe range of (0, inf). Advise to limit its range.
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg1,bkg2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg,sig2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg1,bkg2,sig)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg1,bkg2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg1,sig2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg,sig)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (sig,sig1,sig2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: ()
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) directly selected PDF components: (bkg1,sig,sig1,sig2)
[#1] INFO:Plotting -- RooAbsPdf::plotOn(model) indirectly selected PDF components: (bkg)
Date
July 2008

Definition in file rf205_compplot.C.