void wait_tcutg()
{
	TH2F* h1 =new TH2F("h1", "h1", 100, -2, 2, 100, -2, 2);
	for (Int_t i=0; i<1000; i++) {
		Double_t x = gRandom->Gaus();
		Double_t y = gRandom->Gaus();
		h1->Fill(x,y);
	}
	Double_t xmin = h1->GetXaxis()->GetXmin();
	h1->Draw("colz");
	gPad->Modified();		// make sure 
	gPad->Update();		// hist is drawn
	Double_t *x;
	Int_t cont = 1; 
	Int_t sernr = 0;
	TString new_name;
	do {
		cout << "Please make a TCutG" << endl 
		<< "Terminate if a point is below xmin: " << xmin << endl;
		TCutG* cutg=(TCutG*)gPad->WaitPrimitive("CUTG","CutG");
		cont = 1; 
		if (cutg) {
			cutg->Print();
			x = cutg->GetX();
			for ( Int_t i=0; i< cutg->GetN(); i++ ) {
				if (x[i] < xmin) {
					cont = 0;
					break;
				}
			}
			// make names unique
			if ( cont ) {
				new_name = "mycut_";
				new_name += sernr++;
				cutg->SetName(new_name);
			} else {
				// finito
				delete cutg;
			}
		} else {
			cout << "No cut " << endl;
		}
	} while (cont);
	cout << "Finito" << endl;
}