def small_graph():
graph = Graph()
a = graph.add_node("a")
b = graph.add_node("b")
c = graph.add_node("c")
graph.add_edge_undirected(a, b, 1)
graph.add_edge_undirected(a, c, 2)
graph.add_edge_undirected(b, c, 3)
return (graph, a, b, c)
def test_invalid_node():
graph = Graph()
node1 = graph.add_node(1)
node2 = graph.add_node(2)
other_graph = Graph()
with pytest.raises(InvalidNodeError):
other_graph.add_edge(node1, node2)
def test_from_adj_matrix():
graph = Graph.from_adjacency_matrix([[None, 2, 3], [4, None, 6],
[7, None, None]])
assert graph.get_number_of_nodes() == 3
assert len(list(graph.get_edges())) == 5
def test_no_loops_allowed():
graph = Graph()
node = graph.add_node("node")
with pytest.raises(LoopError):
graph.add_edge(node, node)
def test_from_matrix_not_square():
with pytest.raises(ValueError):
graph = Graph.from_adjacency_matrix([[None, 2, 3], [4, None, 6]])
def large_graph():
graph = Graph()
bos = graph.add_node("bos")
pvd = graph.add_node("pvd")
jfk = graph.add_node("jfk")
bwi = graph.add_node("bwi")
ordd = graph.add_node("ordd")
mia = graph.add_node("mia")
dfw = graph.add_node("dfw")
sfo = graph.add_node("sfo")
lax = graph.add_node("lax")
graph.add_edge_undirected(bos, sfo, 2704)
graph.add_edge_undirected(bos, ordd, 867)
graph.add_edge_undirected(bos, jfk, 187)
graph.add_edge_undirected(bos, mia, 1258)
graph.add_edge_undirected(pvd, jfk, 144)
graph.add_edge_undirected(pvd, ordd, 849)
graph.add_edge_undirected(jfk, ordd, 740)
graph.add_edge_undirected(jfk, dfw, 1391)
graph.add_edge_undirected(jfk, bwi, 184)
graph.add_edge_undirected(jfk, mia, 1090)
graph.add_edge_undirected(bwi, ordd, 621)
graph.add_edge_undirected(bwi, mia, 946)
graph.add_edge_undirected(ordd, dfw, 802)
graph.add_edge_undirected(ordd, sfo, 1846)
graph.add_edge_undirected(mia, dfw, 1121)
graph.add_edge_undirected(mia, lax, 2342)
graph.add_edge_undirected(dfw, sfo, 1464)
graph.add_edge_undirected(dfw, lax, 1235)
graph.add_edge_undirected(sfo, lax, 337)
return graph, bos, lax