#include "RooRealVar.h"
 #include "RooDataSet.h"
 #include "RooGaussian.h"
 #include "RooConstVar.h"
 #include "RooChebychev.h"
 #include "RooAddPdf.h"
 #include "RooSimultaneous.h"
 #include "RooCategory.h"
 #include "TCanvas.h"
 #include "TAxis.h"
 #include "RooPlot.h"
 
 void MultiDim_Fit()
 {
 
 		
 
    // Create variables
	RooRealVar MBC("MBC","Mbc [GeV/c^{2}]",5.23,5.29);
	RooRealVar DELTAE("DELTAE", "#Delta E [GeV]", -0.3, 0.3);
 
    
    // Construct signal pdf
    
  	//--- Signal mbc ---//
	RooRealVar Sig_mean_Mbc("Sig_mean_Mbc","#mu_Mbc", 5.279787, 5.25, 5.29);
	RooRealVar Sig_sigma_Mbc("Sig_sigma_Mbc","#sigma_Mbc", 0.003, 0.0, 1.0);
	RooGaussian Sig_Mbc("Sig_Mbc", "Sig_Mbc", MBC, Sig_mean_Mbc, Sig_sigma_Mbc);


  	//--- Signal for DELTAE ---//
	RooRealVar Sig_mean_deltaE("Sig_mean_deltaE","#mu_DELTAE", 0.0, -0.1, 0.1);
	RooRealVar Sig_sigma_deltaE("Sig_sigma_deltaE","#sigma_DELTAE", 0.02, 0.0, 1.0);
	RooGaussian Sig_deltaE("Sig_deltaE", "Sig_deltaE", DELTAE, Sig_mean_deltaE, Sig_sigma_deltaE);


	//--- Create Multi-dimensiona PDF
	RooProdPdf Prod("Prod","Prod",RooArgList(Sig_Mbc,Sig_deltaE)) ; 
      	
	// Generate a toy MC dataset
	RooDataSet* data = Prod.generate(RooArgSet(MBC,DELTAE), 2000);
	
	// Perform extended ML fit to toy data:
	Prod.fitTo(*data);
	
	// Create RooPlot object to plot toy data and fit overlaid:
	RooPlot* xframe = MBC.frame();
	data->plotOn(xframe);
	Prod.plotOn(xframe);
	
	RooPlot* yframe = DELTAE.frame();
	data->plotOn(yframe);
	Prod.plotOn(yframe);


	//Create canvases and plot
	TCanvas *Cx = new TCanvas("Cx", "Cx");
	Cx->cd();
	xframe->Draw();
	

	TCanvas *Cy = new TCanvas("Cy", "Cy");
	Cy->cd();
	yframe->Draw();
	


	
}