def testCritical(self):
# is_critical graphs
g = nx.Graph()
g.add_node(0)
g = join(g, g)
g = join(g, g)
d = DalGraph(g)
result = d.is_critical()
self.assertEqual(result, True)
g = make_wheel(6)
d = DalGraph(g)
result = d.is_critical()
self.assertEqual(result, True)
d = DalGraph(make_cycle(5))
result = d.is_critical()
self.assertEqual(result, True)
# test non is_critical
d = DalGraph(make_claw())
result = d.is_critical()
self.assertEqual(result, False)
d = DalGraph(make_co_claw())
result = d.is_critical()
self.assertEqual(result, False)
