private void isolateSubgraph(Subgraph subgraph, Node member) {
		Edge edge = null;
		for (int i = 0; i < member.incoming.size(); i++) {
			edge = member.incoming.getEdge(i);
			if (!subgraph.isNested(edge.source) && !edge.flag)
				removeEdge(edge);
		}
		for (int i = 0; i < member.outgoing.size(); i++) {
			edge = member.outgoing.getEdge(i);
			if (!subgraph.isNested(edge.target) && !edge.flag)
				removeEdge(edge);
		}
		if (member instanceof Subgraph) {
			NodeList members = ((Subgraph) member).members;
			for (int i = 0; i < members.size(); i++)
				isolateSubgraph(subgraph, members.getNode(i));
		}
	}