def test_graph_conversions():
igraph = ig.Graph.Star(6)
g = Graph.from_igraph(igraph)
assert g.n_nodes == igraph.vcount()
assert g.edges() == igraph.get_edgelist()
assert all(c == 0 for c in g._edge_colors)
nxg = nx.star_graph(5)
g = Graph.from_networkx(nxg)
assert g.n_nodes == igraph.vcount()
assert g.edges() == igraph.get_edgelist()
assert all(c == 0 for c in g._edge_colors)
igraph = ig.Graph()
igraph.add_vertices(3)
igraph.add_edges(
[(0, 1), (1, 2)],
attributes={
"color": ["red", "blue"],
},
)
with pytest.raises(ValueError, match="not all colors are integers"):
_ = Graph.from_igraph(igraph)
igraph = ig.Graph()
igraph.add_vertices(3)
igraph.add_edges(
[(0, 1), (1, 2)],
attributes={
"color": [0, 1],
},
)
g = Graph.from_igraph(igraph)
assert g.edges(color=0) == [(0, 1)]
assert g.edges(color=1) == [(1, 2)]
def test_is_bipartite():
for i in range(1, 10):
for j in range(1, i * i):
x = nx.dense_gnm_random_graph(i, j)
y = Graph.from_networkx(x)
if len(x) == len(
set((i for (i, j) in x.edges())) | set((j for (i, j) in x.edges()))
):
assert y.is_bipartite() == nx.is_bipartite(x)
def test_is_connected():
for i in range(5, 10):
for j in range(i + 1, i * i):
x = nx.dense_gnm_random_graph(i, j)
y = Graph.from_networkx(x)
if len(x) == len(
set((i for (i, j) in x.edges)) | set((j for (i, j) in x.edges))
):
assert y.is_connected() == nx.is_connected(x)
else:
assert not nx.is_connected(x)