def test_petersen(self):
        from random import sample
        P=nx.petersen_graph()
        def cheeger(G,k):
            return min([float(len(nx.node_boundary(G,sample(G.nodes(),k))))/k 
                        for n in range(100)])

        assert_almost_equals(cheeger(P,1),3.00,places=2)
        assert_almost_equals(cheeger(P,2),2.00,places=2)
        assert_almost_equals(cheeger(P,3),1.67,places=2)
        assert_almost_equals(cheeger(P,4),1.00,places=2)
        assert_almost_equals(cheeger(P,5),0.80,places=2)
Put all aggregate types together, just because
dataset/ETHPy150Open gkno/gkno_launcher/src/networkx/algorithms/tests/test_boundary.py/TestBoundary.test_petersen--crossover with--dataset/ETHPy150Open RobotLocomotion/director/src/python/urdf_parser_py/xml_reflection/core.py/Object.lump_aggregates