void Projected2D_Simple()
{
TStopwatch twatch;
twatch.Start(); 

	RooRealVar x("x","x",0.,10.);
	RooRealVar y("y","y",0.,10.);

	RooRealVar mu0("mu0","mu0",1.,0.,10.);
	RooRealVar mu1("mu1","mu1",0.5,0.,10.);

	RooRealVar sigma0("sigma0","sigma0",1.5,0.,10.);
	RooRealVar sigma1("sigma1","sigma1",0.,0.,10.);
		
	RooPolyVar mean("mean","mean",x,RooArgSet(mu0,mu1));// mean of pdf(y) depends on x
	RooPolyVar sigma("sigma","sigma",x,RooArgSet(sigma0,sigma1));// sigma of pdf(y) depends on x 

	RooGaussian model_y("model_y","model_y",y,mean,sigma);// pdf(y|x)
	RooGaussian model_x("model_x","model_x",x,RooFit::RooConst(5),RooFit::RooConst(0.1));// pdf(x)

	RooProdPdf model_2D("model_2D","model_2D",model_x,RooFit::Conditional(model_y,y));//2D model: pdf(x,y)=pdf(y|x)*pdf(x)

	RooDataHist* Data=model_2D.generateBinned(RooArgSet(x,y),1000);
	RooDataHist* y_Data=(RooDataHist*)Data->reduce(y);


//---- Project 2D PDF 
	RooAbsPdf* model_2D_ProjX=model_2D.createProjection(y);// pdf(x)=\int pdf(x,y)*dy
	RooAbsPdf* model_2D_ProjY=model_2D.createProjection(x);// pdf(x)=\int pdf(x,y)*dx

//----Creating NLL variable and minimisation 
y.setRange("R",0.,10.);
RooAbsReal* nll =(RooAbsReal*) model_2D_ProjY->createNLL(*y_Data,RooFit::Verbose(),RooFit::Optimize(kTRUE)

//,RooFit::Range("R")

); //----With this syntax Range does work but forces num int. even if anal. int. available 

cout<<"Value of Neg. log-likelihood = "<<nll->getVal()<<endl;


//---- Plotting 

RooPlot* xFrame=x.frame();
RooPlot* yFrame=y.frame();

y_Data->plotOn(yFrame,RooFit::MarkerStyle(2));
//model_2D.plotOn(xFrame,RooFit::LineColor(2));
//model_2D.plotOn(yFrame,RooFit::LineColor(2));

//model_x.plotOn(xFrame,RooFit::LineColor(3));
//model_y.plotOn(yFrame,RooFit::LineColor(3));

model_2D_ProjX->plotOn(xFrame);
model_2D_ProjY->plotOn(yFrame);

TCanvas *c0 = new TCanvas("c0","c0",350,50,750,550);
c0->Divide(2);
c0->cd(1);
xFrame->Draw();

c0->cd(2);
yFrame->Draw();

twatch.Stop();
twatch.Print();
return;

		
	
	
}