{
	using namespace RooFit;

	RooRealVar x("x","x",-5,5);
	RooRealVar y("y","y",-5,5);
	RooRealVar sx("sx","sx",0.1,0,5);
	RooRealVar sy("sy","sy",0.1,0,5);
	RooRealVar mx("mx","mx",0,-5,5);
	RooRealVar my("my","my",0,-5,5);
	
	RooGaussian gx("gx","gx",x,mx,sx);
	RooGaussian gy("gy","gy",y,my,sy);

	RooProdPdf gxy("gxy","gxy",gx,gy);


	RooDataSet *data = gxy.generate(RooArgSet(x,y), 2000);
	gxy.fitTo(*data);
	RooPlot *framex = x.frame();
	RooPlot *framey = y.frame();
	data->plotOn(framex);	data->plotOn(framey);
	gxy.plotOn(framex);	gxy.plotOn(framey);

	TCanvas *c = new TCanvas("c");
	TCanvas *c2 = new TCanvas("c2");
	c->Divide(2,2);
	c->cd(1);	framex->Draw();
	c->cd(2);	framey->Draw();


	RooRealVar dmx("dmx","dmx",0);
	RooRealVar smearx("smearx","smearx",1);
	RooGaussian g_smearx("g_smearx","",x,dmx,smearx);
	x.setBins(10000,"fft");
	y.setBins(10000,"fft");
	//RooNumConvPdf fftconv("fftconv","fftconv",x,gxy,g_smearx);
	RooFFTConvPdf fftconv("fftconv","fftconv",x,gxy,g_smearx);

	
	RooDataSet *data_fft = fftconv.generate(RooArgSet(x,y), 200);
	fftconv.fitTo(*data_fft);
	RooPlot *frame_fftx = x.frame();
	RooPlot *frame_ffty = y.frame();
	data_fft->plotOn(frame_fftx,Binning(20));	data_fft->plotOn(frame_ffty,Binning(20));
	fftconv.plotOn(frame_fftx);	fftconv.plotOn(frame_ffty);

	c->cd(3);	frame_fftx->Draw();
	c->cd(4);	frame_ffty->Draw();

	c2.cd();
	TH1* h = fftconv.createHistogram("x,y",50,50);
	h->SetLineColor(kBlue);
	h->Draw("surf");
}