54 lines
1.9 KiB
Python
54 lines
1.9 KiB
Python
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from itertools import chain
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import networkx as nx
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import pytest
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class TestIsSemiconnected(object):
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def test_undirected(self):
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pytest.raises(nx.NetworkXNotImplemented, nx.is_semiconnected,
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nx.Graph())
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pytest.raises(nx.NetworkXNotImplemented, nx.is_semiconnected,
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nx.MultiGraph())
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def test_empty(self):
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pytest.raises(nx.NetworkXPointlessConcept, nx.is_semiconnected,
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nx.DiGraph())
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pytest.raises(nx.NetworkXPointlessConcept, nx.is_semiconnected,
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nx.MultiDiGraph())
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def test_single_node_graph(self):
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G = nx.DiGraph()
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G.add_node(0)
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assert nx.is_semiconnected(G)
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def test_path(self):
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G = nx.path_graph(100, create_using=nx.DiGraph())
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assert nx.is_semiconnected(G)
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G.add_edge(100, 99)
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assert not nx.is_semiconnected(G)
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def test_cycle(self):
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G = nx.cycle_graph(100, create_using=nx.DiGraph())
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assert nx.is_semiconnected(G)
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G = nx.path_graph(100, create_using=nx.DiGraph())
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G.add_edge(0, 99)
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assert nx.is_semiconnected(G)
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def test_tree(self):
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G = nx.DiGraph()
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G.add_edges_from(chain.from_iterable([(i, 2 * i + 1), (i, 2 * i + 2)]
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for i in range(100)))
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assert not nx.is_semiconnected(G)
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def test_dumbbell(self):
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G = nx.cycle_graph(100, create_using=nx.DiGraph())
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G.add_edges_from((i + 100, (i + 1) % 100 + 100) for i in range(100))
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assert not nx.is_semiconnected(G) # G is disconnected.
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G.add_edge(100, 99)
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assert nx.is_semiconnected(G)
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def test_alternating_path(self):
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G = nx.DiGraph(chain.from_iterable([(i, i - 1), (i, i + 1)]
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for i in range(0, 100, 2)))
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assert not nx.is_semiconnected(G)
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