#ifndef __CINT__
#include "RooGlobalFunc.h"
#endif
#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "RooConstVar.h"
#include "RooPolynomial.h"
#include "RooAddPdf.h"
#include "RooProdPdf.h"
#include "RooMCStudy.h"
#include "RooPlot.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "TH1.h"

using namespace RooFit;


void TestPulls()
{
  double yield = 200;

  // Observable
  RooRealVar x("x","x",-10,10) ;

  // Signal component
  RooRealVar m("m","m",0,-10,10) ;
  RooRealVar s("s","s",2,0.1,10) ;
  RooGaussian g("g","g",x,m,s) ;

  m.setConstant(false);
  s.setConstant(false);

  RooMCStudy mcs(g,x,Silence(),FitOptions(PrintLevel(-1))) ;
  mcs.generateAndFit(1000,yield,true) ;

  RooDataSet* toySample = (RooDataSet*)mcs.genData(0);
  g.fitTo(*toySample);
  RooPlot* frame0 = x.frame(40);
  toySample->plotOn(frame0);
  g.plotOn(frame0);

  RooPlot* frame1  = mcs.plotParam(s,Bins(40)) ;
  frame1->SetTitle("Distribution of fitted s values") ;

  RooPlot* frame2 = mcs.plotPull(s,Bins(40),FitGauss()) ;
  frame1->SetTitle("Distribution of s pull values") ;

  TCanvas* c = new TCanvas("TestPulls","TestPulls",1200,400);
  c->Divide(3) ;
  c->cd(1) ; gPad->SetLeftMargin(0.15) ; frame0->GetYaxis()->SetTitleOffset(1.4) ; frame0->Draw() ;
  c->cd(2) ; gPad->SetLeftMargin(0.15) ; frame1->GetYaxis()->SetTitleOffset(1.4) ; frame1->Draw() ;
  c->cd(3) ; gPad->SetLeftMargin(0.15) ; frame2->GetYaxis()->SetTitleOffset(1.4) ; frame2->Draw() ;
}