def test_wheel_true(self):
v = 10
G = Graph(v, False)
for node in range(v):
G.add_node(node)
hub = 0
for node in range(1, v):
G.add_edge(Edge(hub, node))
G.add_edge(Edge(node, node+1 if node < v-1 else 1))
self.assertTrue(is_wheel(G))
algorithm = WheelGraph(G)
algorithm.run()
self.assertEqual(algorithm.hub, hub)
def test_wheel_false2(self):
# 1---2 missing Edge(0, 3) or Edge(1, 3)
# |\ /|
# | 0 |
# |/ |
# 4---3
v = 5
G = Graph(v, False)
for node in range(v):
G.add_node(node)
edges = [
Edge(0, 1), Edge(0, 2), Edge(0, 4),
Edge(1, 2), Edge(2, 3), Edge(3, 4), Edge(1, 4)]
for edge in edges:
G.add_edge(edge)
G.add_edge(Edge(2, 4)) # bad edge
self.assertFalse(is_wheel(G))
self.assertRaises(ValueError, lambda: WheelGraph(G).run())
def test_wheel_false(self):
# 0---+ +---5 windmill graph
# |\ \ / /| https://en.wikipedia.org/wiki/Windmill_graph
# | 1---3---4 |
# |/ / \ \|
# 2---+ +---6
v = 7
G = Graph(v, False)
for node in range(v):
G.add_node(node)
edges = [
Edge(0, 1), Edge(1, 2), Edge(0, 2), Edge(4, 5),
Edge(5, 6), Edge(4, 6), Edge(0, 3), Edge(1, 3),
Edge(2, 3), Edge(3, 5), Edge(3, 4), Edge(3, 6)]
for edge in edges:
G.add_edge(edge)
self.assertFalse(is_wheel(G))
self.assertRaises(ValueError, lambda: WheelGraph(G).run())
def test_is_wheel(self):
G = self.graph_factory.make_complete(n=3, directed=False)
self.assertFalse(is_wheel(G))
self.assertRaises(ValueError, lambda: WheelGraph(G).run())
def test_k4(self): # complete graph K4 = W4
G = self.graph_factory.make_complete(n=4, directed=False)
self.assertTrue(is_wheel(G))
algorithm = WheelGraph(G)
algorithm.run()
self.assertEqual(algorithm.hub, 0)
