%%cpp -d
#include "RooRealVar.h"
#include "RooGaussian.h"
#include "RooProdPdf.h"
#include "RooAbsReal.h"
#include "RooPlot.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "TH1.h"
using namespace RooFit;

RooRealVar x("x", "x", -10, 10);
RooRealVar y("y", "y", -10, 10);

RooGaussian gx("gx", "gx", x, -2.0, 3.0);
RooGaussian gy("gy", "gy", y, +2.0, 2.0);

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

cout << "gxy = " << gxy.getVal() << endl;

RooArgSet nset_xy(x, y);
cout << "gx_Norm[x,y] = " << gxy.getVal(&nset_xy) << endl;

std::unique_ptr<RooAbsReal> igxy{gxy.createIntegral(RooArgSet(x, y))};
cout << "gx_Int[x,y] = " << igxy->getVal() << endl;

RooArgSet nset_x(x);
cout << "gx_Norm[x] = " << gxy.getVal(&nset_x) << endl;

RooArgSet nset_y(y);
cout << "gx_Norm[y] = " << gxy.getVal(&nset_y) << endl;

x.setRange("signal", -5, 5);
y.setRange("signal", -3, 3);

std::unique_ptr<RooAbsReal> igxy_sig{gxy.createIntegral({x, y}, NormSet(RooArgSet(x, y)), Range("signal"))};
cout << "gx_Int[x,y|signal]_Norm[x,y] = " << igxy_sig->getVal() << endl;

std::unique_ptr<RooAbsReal> gxy_cdf{gxy.createCdf(RooArgSet(x, y))};

TH1 *hh_cdf = gxy_cdf->createHistogram("hh_cdf", x, Binning(40), YVar(y, Binning(40)));
hh_cdf->SetLineColor(kBlue);

new TCanvas("rf308_normintegration2d", "rf308_normintegration2d", 600, 600);
gPad->SetLeftMargin(0.15);
hh_cdf->GetZaxis()->SetTitleOffset(1.8);
hh_cdf->Draw("surf");

gROOT->GetListOfCanvases()->Draw()