def testCycleAvoidance(self):
# should orient X->Y
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('Y', 'X'), ('X', 'Z'), ('Z', 'Y')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertTrue(didOrient)
self.assertEqual(3, len(partiallyDirectedGraph.edges()))
# should orient X<-Y
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('Y', 'X'), ('Z', 'X'), ('Y', 'Z')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertTrue(didOrient)
self.assertEqual(3, len(partiallyDirectedGraph.edges()))
# should orient no edges if two are unoriented in triple
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('Y', 'X'), ('X', 'Z'), ('Z', 'X'), ('Y', 'Z')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertFalse(didOrient)
self.assertEqual(5, len(partiallyDirectedGraph.edges()))
# should orient no edges if X and Y are not adjacent (unshieled triple)
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Z'), ('Z', 'X'), ('Y', 'Z')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertFalse(didOrient)
self.assertEqual(3, len(partiallyDirectedGraph.edges()))
# should orient no edges because X already oriented to Y
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('X', 'Z'), ('Z', 'Y')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertFalse(didOrient)
self.assertEqual(3, len(partiallyDirectedGraph.edges()))
# should orient no edges because common cause (no cycle to avoid for a shielded triple)
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('Y', 'X'), ('Z', 'X'), ('Z', 'Y')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertFalse(didOrient)
self.assertEqual(4, len(partiallyDirectedGraph.edges()))
# should orient no edges because common effect (no cycle to avoid for a shielded triple)
partiallyDirectedGraph = nx.DiGraph()
partiallyDirectedGraph.add_nodes_from(['X', 'Y', 'Z'])
edgePairs = [('X', 'Y'), ('Y', 'X'), ('X', 'Z'), ('Y', 'Z')]
partiallyDirectedGraph.add_edges_from(edgePairs)
didOrient = EdgeOrientation.applyCycleAvoidance(partiallyDirectedGraph)
self.assertFalse(didOrient)
self.assertEqual(4, len(partiallyDirectedGraph.edges()))
