annotate env/lib/python3.9/site-packages/networkx/algorithms/approximation/tests/test_dominating_set.py @ 0:4f3585e2f14b draft default tip

"planemo upload commit 60cee0fc7c0cda8592644e1aad72851dec82c959"
author shellac
date Mon, 22 Mar 2021 18:12:50 +0000
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1 import networkx as nx
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2 from networkx.algorithms.approximation import min_weighted_dominating_set
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3 from networkx.algorithms.approximation import min_edge_dominating_set
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4
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5
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6 class TestMinWeightDominatingSet:
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7 def test_min_weighted_dominating_set(self):
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8 graph = nx.Graph()
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9 graph.add_edge(1, 2)
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10 graph.add_edge(1, 5)
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11 graph.add_edge(2, 3)
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12 graph.add_edge(2, 5)
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13 graph.add_edge(3, 4)
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14 graph.add_edge(3, 6)
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15 graph.add_edge(5, 6)
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16
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17 vertices = {1, 2, 3, 4, 5, 6}
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18 # due to ties, this might be hard to test tight bounds
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19 dom_set = min_weighted_dominating_set(graph)
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20 for vertex in vertices - dom_set:
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21 neighbors = set(graph.neighbors(vertex))
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22 assert len(neighbors & dom_set) > 0, "Non dominating set found!"
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23
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24 def test_star_graph(self):
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25 """Tests that an approximate dominating set for the star graph,
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26 even when the center node does not have the smallest integer
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27 label, gives just the center node.
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28
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29 For more information, see #1527.
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30
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31 """
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32 # Create a star graph in which the center node has the highest
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33 # label instead of the lowest.
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34 G = nx.star_graph(10)
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35 G = nx.relabel_nodes(G, {0: 9, 9: 0})
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36 assert min_weighted_dominating_set(G) == {9}
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37
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38 def test_min_edge_dominating_set(self):
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39 graph = nx.path_graph(5)
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40 dom_set = min_edge_dominating_set(graph)
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41
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42 # this is a crappy way to test, but good enough for now.
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43 for edge in graph.edges():
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44 if edge in dom_set:
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45 continue
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46 else:
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47 u, v = edge
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48 found = False
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49 for dom_edge in dom_set:
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50 found |= u == dom_edge[0] or u == dom_edge[1]
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51 assert found, "Non adjacent edge found!"
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52
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53 graph = nx.complete_graph(10)
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54 dom_set = min_edge_dominating_set(graph)
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55
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56 # this is a crappy way to test, but good enough for now.
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57 for edge in graph.edges():
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58 if edge in dom_set:
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59 continue
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60 else:
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61 u, v = edge
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62 found = False
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63 for dom_edge in dom_set:
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64 found |= u == dom_edge[0] or u == dom_edge[1]
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65 assert found, "Non adjacent edge found!"