def build_digraph(degree_sequence, nodes=None):
''' Generates directed graph of the given degree
sequence (out, in). If nodes are provided, each
node will have the corresponding data. '''
if not is_valid_directed_degree_sequence(degree_sequence):
raise InvalidDegreeSequence('Invalid degree sequence!')
graph = DiGraph()
degree_node = []
if not nodes:
nodes = count()
for item in map(lambda x, z: [x[0], x[1], z], degree_sequence, nodes):
degree_node.append(item)
degree_node.sort(key=lambda x: x[1], reverse=True)
degree_node.sort(key=lambda x: x[0], reverse=True)
degree_node = deque(degree_node)
while degree_node:
out_degree, in_degree, node = degree_node.popleft()
if in_degree == out_degree == 0:
graph.add_node(node)
continue
for out_in_node in degree_node:
if out_degree == 0:
break
if out_in_node[1]:
out_in_node[1] -= 1
out_degree -= 1
graph.add_edge(node, out_in_node[2])
if in_degree:
degree_node.append([out_degree, in_degree, node])
return graph
class BasicDiGraphTest(unittest.TestCase):
def setUp(self):
self.nodes = [1, 'Sofia', 'Bourgas', 5.6555]
self.edges = [(1, 'Sofia'), ('Sofia', 'Bourgas')]
self.graph = DiGraph()
for node in self.nodes:
self.graph.add_node(node)
for edge in self.edges:
self.graph.add_edge(*edge)
def tearDown(self):
del self.nodes
del self.graph
def test_nodes_in_graph(self):
for node in self.nodes:
self.assertTrue(node in self.graph)
self.assertFalse('NotANode' in self.graph)
def test_edges_successors_predecessors(self):
for (u, v) in self.edges:
self.assertTrue(u in self.graph.get_predecessors(v))
self.assertTrue(v in self.graph.get_successors(u))
self.assertFalse(v in self.graph.get_predecessors(u))
self.assertFalse(u in self.graph.get_successors(v))
def test_has_edge(self):
for (u, v) in self.edges:
self.assertTrue(self.graph.has_edge(u, v))
def test_remove_edge(self):
u, v = 1, 'Bourgas'
self.assertFalse(self.graph.has_edge(u, v))
self.graph.add_edge(u, v)
self.assertTrue(self.graph.has_edge(u, v))
self.graph.remove_edge(u, v)
self.assertFalse(self.graph.has_edge(u, v))
def test_is_directed(self):
self.assertTrue(self.graph.is_directed())
def test_in_degree(self):
self.assertEqual(self.graph.in_degree('Sofia'), 1)
self.assertEqual(self.graph.in_degree(1), 0)
def test_out_degree(self):
self.assertEqual(self.graph.out_degree('Sofia'), 1)
self.assertEqual(self.graph.out_degree('Bourgas'), 0)
def test_degree(self):
self.assertEqual(self.graph.degree('Sofia'), 2)
self.assertEqual(self.graph.degree(5.6555), 0)
def test_order(self):
self.assertEqual(self.graph.order(), len(self.nodes))
self.graph.add_node('AloneNode')
self.assertEqual(self.graph.order(), len(self.nodes)+1)
self.graph.remove_node('AloneNode')
self.assertEqual(self.graph.order(), len(self.nodes))
def test_size(self):
self.assertEqual(self.graph.size(), len(self.edges))
self.graph.add_edge(100, 100)
self.assertEqual(self.graph.size(), len(self.edges) + 1)
self.graph.remove_node(100)
self.assertEqual(self.graph.size(), len(self.edges))
