#include <iostream>
#include "TH1.h"
#include "TFile.h"
#include "RooRealVar.h"
#include "RooFormulaVar.h"
#include "RooDataHist.h"
#include "RooPlot.h"
#include "RooGenericPdf.h"
#include "RooGaussian.h"
#include "RooProdPdf.h"
#include "RooFFTConvPdf.h"
#include "RooNumConvPdf.h"
#include "RooNLLVar.h"
#include "RooMinuit.h"
#include "RooFitResult.h"
#include "TCanvas.h"
#include "TROOT.h"
#include "RooAddPdf.h"
#include "RooChi2Var.h"
#include "RooArgSet.h"
#include <cmath>
#include <string>

using namespace RooFit;

void fit_work() {

  TFile file("fitFile");

 RooRealVar obs("obs","obs",-30.,30.);
 RooRealVar testsig("testsig","testsig",3.0);
 RooRealVar testsig2("testsig2","testsig2",4.0);
 RooRealVar testsig3("testsig3","testsig3",5.0);
 RooRealVar c1("c1","c1",0.);
 RooGaussian gt1("gt1","gt1",obs,c1,testsig);
 RooGaussian gt2("gt2","gt2",obs,c1,testsig2);
 RooGaussian gt3("gt3","gt3",obs,c1,testsig3);
 obs.setBins(10000,"fft");
 RooFFTConvPdf conv("conv","conv",obs,gt1,gt2);
 RooRealVar one("one","one",1.);
 RooRealVar mOne("mOne","mOne",-1.);
 RooAddPdf diff("diff","diff",RooArgList(gt3,conv),RooArgList(one,mOne));
 RooPlot* obsframe = obs.frame();
 conv.plotOn(obsframe,LineColor(kGreen));
 gt3.plotOn(obsframe,LineColor(kMagenta));
 diff.plotOn(obsframe,LineColor(kRed));
 obsframe->Draw();
}