diff env/lib/python3.9/site-packages/networkx/algorithms/approximation/tests/test_ramsey.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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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/env/lib/python3.9/site-packages/networkx/algorithms/approximation/tests/test_ramsey.py	Mon Mar 22 18:12:50 2021 +0000
@@ -0,0 +1,31 @@
+import networkx as nx
+import networkx.algorithms.approximation as apxa
+
+
+def test_ramsey():
+    # this should only find the complete graph
+    graph = nx.complete_graph(10)
+    c, i = apxa.ramsey_R2(graph)
+    cdens = nx.density(graph.subgraph(c))
+    assert cdens == 1.0, "clique not correctly found by ramsey!"
+    idens = nx.density(graph.subgraph(i))
+    assert idens == 0.0, "i-set not correctly found by ramsey!"
+
+    # this trival graph has no cliques. should just find i-sets
+    graph = nx.trivial_graph()
+    c, i = apxa.ramsey_R2(graph)
+    assert c == {0}, "clique not correctly found by ramsey!"
+    assert i == {0}, "i-set not correctly found by ramsey!"
+
+    graph = nx.barbell_graph(10, 5, nx.Graph())
+    c, i = apxa.ramsey_R2(graph)
+    cdens = nx.density(graph.subgraph(c))
+    assert cdens == 1.0, "clique not correctly found by ramsey!"
+    idens = nx.density(graph.subgraph(i))
+    assert idens == 0.0, "i-set not correctly found by ramsey!"
+
+    # add self-loops and test again
+    graph.add_edges_from([(n, n) for n in range(0, len(graph), 2)])
+    cc, ii = apxa.ramsey_R2(graph)
+    assert cc == c
+    assert ii == i