def test_zigzag(self):
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
i = graph.Node('i')
j = graph.Node('j')
gr.addnodes(a, b, c, d, e, f, g, h, i, j)
gr.addedge(a, b)
gr.addedge(a, c)
gr.addedge(b, d)
gr.addedge(b, e)
gr.addedge(c, f)
gr.addedge(d, g)
gr.addedge(d, h)
gr.addedge(f, i)
gr.addedge(f, j)
r = graph.bfs_zigzag(gr, a)
self.assertEqual('abcdefghij', r)
def test_kruskal(self):
# https://en.wikipedia.org/wiki/Kruskal%27s_algorithm
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
gr.addnodes(a, b, c, d, e, f, g)
gr.addedge(a, d, 5)
gr.addedge(a, b, 7)
gr.addedge(b, c, 8)
gr.addedge(b, d, 9)
gr.addedge(b, e, 7)
gr.addedge(c, e, 5)
gr.addedge(d, e, 15)
gr.addedge(d, f, 6)
gr.addedge(f, e, 8)
gr.addedge(e, g, 9)
gr.addedge(f, g, 11)
mst = graph.kruskal(gr)
for ex in mst.edges():
print ex
def test_sorting(self):
# make sure that a node's neighbors are
# presented in sorted order.
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
gr.addnodes(a, b, c, d, e, f, g, h)
gr.addedge(a, h)
gr.addedge(a, g)
gr.addedge(a, f)
gr.addedge(a, e)
gr.addedge(a, d)
gr.addedge(a, c)
gr.addedge(a, b)
k = ""
for n in gr.neighbors(a):
k += str(n)
self.assertEqual('bcdefgh', k)
def test_bfs(self):
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
gr.addnodes(a, b, c, d, e, f, g, h)
gr.addedge(a, b)
gr.addedge(a, g)
gr.addedge(a, d)
gr.addedge(b, e)
gr.addedge(b, f)
gr.addedge(c, f)
gr.addedge(c, h)
gr.addedge(d, f)
gr.addedge(e, g)
r = graph.bfs(gr, a)
self.assertEqual('abdgefch', r)
def test_addNode(self):
g = graph.UGraph()
n1 = graph.Node('a')
g.addnode(n1)
self.assertEqual(1, len(g))
with self.assertRaises(graph.GraphException):
g.addnode(n1)
n2 = graph.Node('a')
with self.assertRaises(graph.GraphException):
g.addnode(n2)
self.assertEqual(1, len(g))
n3 = graph.Node('b')
g.addnode(n3)
self.assertEqual(2, len(g))
self.assertTrue(g.contains(n1))
self.assertTrue(g.contains(n2))
self.assertTrue(g.contains(n3))
n4 = graph.Node('notMe')
self.assertFalse(g.contains(n4))
def test_bool(self):
g = graph.UGraph()
self.assertFalse(g)
self.assertEqual(0, len(g))
n = graph.Node('hello')
g.addnode(n)
self.assertTrue(g)
self.assertEqual(1, len(g))
def test_addNodes(self):
# new convenience method
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
gr.addnodes(a, b, c, d, e, f, g, h)
self.assertEqual(8, len(gr))
def test_addEdge(self):
g = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
with self.assertRaises(Exception):
g.addedge(a, b)
g.addnode(a)
with self.assertRaises(Exception):
g.addedge(a, b)
g.addnode(b)
g.addedge(a, b)
def test_nodes_generator(self):
# new convenience method
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
gr.addnodes(a, b, c, d, e, f, g, h)
control = [a, b, c, d, e, f, g, h]
nodes = sorted([n for n in gr.nodes()])
self.assertEqual(control, nodes)
def test_bfs_simple(self):
# graph with one vertex and no edges
# graph with one vertex and one (loop) edge
gr = graph.UGraph()
a = graph.Node('a')
outsider = graph.Node('mr_lonely')
with self.assertRaises(graph.GraphException):
graph.bfs(gr, outsider)
gr.addnode(a)
gr.addedge(a, a)
graph.bfs(gr, a)
def test_dfs(self):
# cf. https://www.youtube.com/watch?v=zLZhSSXAwxI
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
gr.addnodes(a, b, c, d, e, f, g, h)
gr.addedge(a, b)
gr.addedge(a, g)
gr.addedge(a, d)
gr.addedge(b, e)
gr.addedge(b, f)
gr.addedge(c, f)
gr.addedge(c, h)
gr.addedge(d, f)
gr.addedge(e, g)
outsider = graph.Node('mr_lonely')
with self.assertRaises(graph.GraphException):
graph.dfs(gr, outsider)
r = graph.dfs(gr, a)
self.assertEqual('abegfchd', r)
def setUp(self):
# sedgewick, p. 374
gr = graph.UGraph()
a = graph.Node('a')
b = graph.Node('b')
c = graph.Node('c')
d = graph.Node('d')
e = graph.Node('e')
f = graph.Node('f')
g = graph.Node('g')
h = graph.Node('h')
i = graph.Node('i')
j = graph.Node('j')
k = graph.Node('k')
l = graph.Node('l')
m = graph.Node('m')
gr.addnodes(a, b, c, d, e, f, g, h, i, j, k, l, m)
gr.addedge(h, i)
gr.addedge(j, k)
gr.addedge(j, m)
gr.addedge(j, l)
gr.addedge(l, m)
gr.addedge(a, b)
gr.addedge(a, c)
gr.addedge(a, f)
gr.addedge(a, g)
gr.addedge(d, f)
gr.addedge(f, e)
gr.addedge(e, g)
self.sedgewick = gr
