Mercurial > repos > shellac > sam_consensus_v3
diff env/lib/python3.9/site-packages/networkx/algorithms/tests/test_euler.py @ 0:4f3585e2f14b draft default tip
"planemo upload commit 60cee0fc7c0cda8592644e1aad72851dec82c959"
author | shellac |
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date | Mon, 22 Mar 2021 18:12:50 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/env/lib/python3.9/site-packages/networkx/algorithms/tests/test_euler.py Mon Mar 22 18:12:50 2021 +0000 @@ -0,0 +1,191 @@ +import collections + +import pytest + +import networkx as nx + + +class TestIsEulerian: + def test_is_eulerian(self): + assert nx.is_eulerian(nx.complete_graph(5)) + assert nx.is_eulerian(nx.complete_graph(7)) + assert nx.is_eulerian(nx.hypercube_graph(4)) + assert nx.is_eulerian(nx.hypercube_graph(6)) + + assert not nx.is_eulerian(nx.complete_graph(4)) + assert not nx.is_eulerian(nx.complete_graph(6)) + assert not nx.is_eulerian(nx.hypercube_graph(3)) + assert not nx.is_eulerian(nx.hypercube_graph(5)) + + assert not nx.is_eulerian(nx.petersen_graph()) + assert not nx.is_eulerian(nx.path_graph(4)) + + def test_is_eulerian2(self): + # not connected + G = nx.Graph() + G.add_nodes_from([1, 2, 3]) + assert not nx.is_eulerian(G) + # not strongly connected + G = nx.DiGraph() + G.add_nodes_from([1, 2, 3]) + assert not nx.is_eulerian(G) + G = nx.MultiDiGraph() + G.add_edge(1, 2) + G.add_edge(2, 3) + G.add_edge(2, 3) + G.add_edge(3, 1) + assert not nx.is_eulerian(G) + + +class TestEulerianCircuit: + def test_eulerian_circuit_cycle(self): + G = nx.cycle_graph(4) + + edges = list(nx.eulerian_circuit(G, source=0)) + nodes = [u for u, v in edges] + assert nodes == [0, 3, 2, 1] + assert edges == [(0, 3), (3, 2), (2, 1), (1, 0)] + + edges = list(nx.eulerian_circuit(G, source=1)) + nodes = [u for u, v in edges] + assert nodes == [1, 2, 3, 0] + assert edges == [(1, 2), (2, 3), (3, 0), (0, 1)] + + G = nx.complete_graph(3) + + edges = list(nx.eulerian_circuit(G, source=0)) + nodes = [u for u, v in edges] + assert nodes == [0, 2, 1] + assert edges == [(0, 2), (2, 1), (1, 0)] + + edges = list(nx.eulerian_circuit(G, source=1)) + nodes = [u for u, v in edges] + assert nodes == [1, 2, 0] + assert edges == [(1, 2), (2, 0), (0, 1)] + + def test_eulerian_circuit_digraph(self): + G = nx.DiGraph() + nx.add_cycle(G, [0, 1, 2, 3]) + + edges = list(nx.eulerian_circuit(G, source=0)) + nodes = [u for u, v in edges] + assert nodes == [0, 1, 2, 3] + assert edges == [(0, 1), (1, 2), (2, 3), (3, 0)] + + edges = list(nx.eulerian_circuit(G, source=1)) + nodes = [u for u, v in edges] + assert nodes == [1, 2, 3, 0] + assert edges == [(1, 2), (2, 3), (3, 0), (0, 1)] + + def test_multigraph(self): + G = nx.MultiGraph() + nx.add_cycle(G, [0, 1, 2, 3]) + G.add_edge(1, 2) + G.add_edge(1, 2) + edges = list(nx.eulerian_circuit(G, source=0)) + nodes = [u for u, v in edges] + assert nodes == [0, 3, 2, 1, 2, 1] + assert edges == [(0, 3), (3, 2), (2, 1), (1, 2), (2, 1), (1, 0)] + + def test_multigraph_with_keys(self): + G = nx.MultiGraph() + nx.add_cycle(G, [0, 1, 2, 3]) + G.add_edge(1, 2) + G.add_edge(1, 2) + edges = list(nx.eulerian_circuit(G, source=0, keys=True)) + nodes = [u for u, v, k in edges] + assert nodes == [0, 3, 2, 1, 2, 1] + assert edges[:2] == [(0, 3, 0), (3, 2, 0)] + assert collections.Counter(edges[2:5]) == collections.Counter( + [(2, 1, 0), (1, 2, 1), (2, 1, 2)] + ) + assert edges[5:] == [(1, 0, 0)] + + def test_not_eulerian(self): + with pytest.raises(nx.NetworkXError): + f = list(nx.eulerian_circuit(nx.complete_graph(4))) + + +class TestIsSemiEulerian: + def test_is_semieulerian(self): + # Test graphs with Eulerian paths but no cycles return True. + assert nx.is_semieulerian(nx.path_graph(4)) + G = nx.path_graph(6, create_using=nx.DiGraph) + assert nx.is_semieulerian(G) + + # Test graphs with Eulerian cycles return False. + assert not nx.is_semieulerian(nx.complete_graph(5)) + assert not nx.is_semieulerian(nx.complete_graph(7)) + assert not nx.is_semieulerian(nx.hypercube_graph(4)) + assert not nx.is_semieulerian(nx.hypercube_graph(6)) + + +class TestHasEulerianPath: + def test_has_eulerian_path_cyclic(self): + # Test graphs with Eulerian cycles return True. + assert nx.has_eulerian_path(nx.complete_graph(5)) + assert nx.has_eulerian_path(nx.complete_graph(7)) + assert nx.has_eulerian_path(nx.hypercube_graph(4)) + assert nx.has_eulerian_path(nx.hypercube_graph(6)) + + def test_has_eulerian_path_non_cyclic(self): + # Test graphs with Eulerian paths but no cycles return True. + assert nx.has_eulerian_path(nx.path_graph(4)) + G = nx.path_graph(6, create_using=nx.DiGraph) + assert nx.has_eulerian_path(G) + + +class TestFindPathStart: + def testfind_path_start(self): + find_path_start = nx.algorithms.euler._find_path_start + # Test digraphs return correct starting node. + G = nx.path_graph(6, create_using=nx.DiGraph) + assert find_path_start(G) == 0 + edges = [(0, 1), (1, 2), (2, 0), (4, 0)] + assert find_path_start(nx.DiGraph(edges)) == 4 + + # Test graph with no Eulerian path return None. + edges = [(0, 1), (1, 2), (2, 3), (2, 4)] + assert find_path_start(nx.DiGraph(edges)) is None + + +class TestEulerianPath: + def test_eulerian_path(self): + x = [(4, 0), (0, 1), (1, 2), (2, 0)] + for e1, e2 in zip(x, nx.eulerian_path(nx.DiGraph(x))): + assert e1 == e2 + + +class TestEulerize: + def test_disconnected(self): + with pytest.raises(nx.NetworkXError): + G = nx.from_edgelist([(0, 1), (2, 3)]) + nx.eulerize(G) + + def test_null_graph(self): + with pytest.raises(nx.NetworkXPointlessConcept): + nx.eulerize(nx.Graph()) + + def test_null_multigraph(self): + with pytest.raises(nx.NetworkXPointlessConcept): + nx.eulerize(nx.MultiGraph()) + + def test_on_empty_graph(self): + with pytest.raises(nx.NetworkXError): + nx.eulerize(nx.empty_graph(3)) + + def test_on_eulerian(self): + G = nx.cycle_graph(3) + H = nx.eulerize(G) + assert nx.is_isomorphic(G, H) + + def test_on_eulerian_multigraph(self): + G = nx.MultiGraph(nx.cycle_graph(3)) + G.add_edge(0, 1) + H = nx.eulerize(G) + assert nx.is_eulerian(H) + + def test_on_complete_graph(self): + G = nx.complete_graph(4) + assert nx.is_eulerian(nx.eulerize(G)) + assert nx.is_eulerian(nx.eulerize(nx.MultiGraph(G)))