diff env/lib/python3.9/site-packages/networkx/generators/tests/test_harary_graph.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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children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/env/lib/python3.9/site-packages/networkx/generators/tests/test_harary_graph.py	Mon Mar 22 18:12:50 2021 +0000
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+"""Unit tests for the :mod:`networkx.generators.harary_graph` module.
+"""
+
+import pytest
+
+import networkx as nx
+from networkx.generators.harary_graph import hnm_harary_graph
+from networkx.generators.harary_graph import hkn_harary_graph
+from networkx.algorithms.isomorphism.isomorph import is_isomorphic
+
+
+class TestHararyGraph:
+    """
+        Suppose n nodes, m >= n-1 edges, d = 2m // n, r = 2m % n
+    """
+
+    def test_hnm_harary_graph(self):
+        # When d is even and r = 0, the hnm_harary_graph(n,m) is
+        # the circulant_graph(n, list(range(1,d/2+1)))
+        for (n, m) in [(5, 5), (6, 12), (7, 14)]:
+            G1 = hnm_harary_graph(n, m)
+            d = 2 * m // n
+            G2 = nx.circulant_graph(n, list(range(1, d // 2 + 1)))
+            assert is_isomorphic(G1, G2)
+
+        # When d is even and r > 0, the hnm_harary_graph(n,m) is
+        # the circulant_graph(n, list(range(1,d/2+1)))
+        # with r edges added arbitrarily
+        for (n, m) in [(5, 7), (6, 13), (7, 16)]:
+            G1 = hnm_harary_graph(n, m)
+            d = 2 * m // n
+            G2 = nx.circulant_graph(n, list(range(1, d // 2 + 1)))
+            assert set(G2.edges) < set(G1.edges)
+            assert G1.number_of_edges() == m
+
+        # When d is odd and n is even and r = 0, the hnm_harary_graph(n,m)
+        # is the circulant_graph(n, list(range(1,(d+1)/2) plus [n//2])
+        for (n, m) in [(6, 9), (8, 12), (10, 15)]:
+            G1 = hnm_harary_graph(n, m)
+            d = 2 * m // n
+            L = list(range(1, (d + 1) // 2))
+            L.append(n // 2)
+            G2 = nx.circulant_graph(n, L)
+            assert is_isomorphic(G1, G2)
+
+        # When d is odd and n is even and r > 0, the hnm_harary_graph(n,m)
+        # is the circulant_graph(n, list(range(1,(d+1)/2) plus [n//2])
+        # with r edges added arbitrarily
+        for (n, m) in [(6, 10), (8, 13), (10, 17)]:
+            G1 = hnm_harary_graph(n, m)
+            d = 2 * m // n
+            L = list(range(1, (d + 1) // 2))
+            L.append(n // 2)
+            G2 = nx.circulant_graph(n, L)
+            assert set(G2.edges) < set(G1.edges)
+            assert G1.number_of_edges() == m
+
+        # When d is odd and n is odd, the hnm_harary_graph(n,m) is
+        # the circulant_graph(n, list(range(1,(d+1)/2))
+        # with m - n*(d-1)/2 edges added arbitrarily
+        for (n, m) in [(5, 4), (7, 12), (9, 14)]:
+            G1 = hnm_harary_graph(n, m)
+            d = 2 * m // n
+            L = list(range(1, (d + 1) // 2))
+            G2 = nx.circulant_graph(n, L)
+            assert set(G2.edges) < set(G1.edges)
+            assert G1.number_of_edges() == m
+
+        # Raise NetworkXError if n<1
+        n = 0
+        m = 0
+        pytest.raises(nx.NetworkXError, hnm_harary_graph, n, m)
+
+        # Raise NetworkXError if m < n-1
+        n = 6
+        m = 4
+        pytest.raises(nx.NetworkXError, hnm_harary_graph, n, m)
+
+        # Raise NetworkXError if m > n(n-1)/2
+        n = 6
+        m = 16
+        pytest.raises(nx.NetworkXError, hnm_harary_graph, n, m)
+
+    """
+        Suppose connectivity k, number of nodes n
+    """
+
+    def test_hkn_harary_graph(self):
+        # When k == 1, the hkn_harary_graph(k,n) is
+        # the path_graph(n)
+        for (k, n) in [(1, 6), (1, 7)]:
+            G1 = hkn_harary_graph(k, n)
+            G2 = nx.path_graph(n)
+            assert is_isomorphic(G1, G2)
+
+        # When k is even, the hkn_harary_graph(k,n) is
+        # the circulant_graph(n, list(range(1,k/2+1)))
+        for (k, n) in [(2, 6), (2, 7), (4, 6), (4, 7)]:
+            G1 = hkn_harary_graph(k, n)
+            G2 = nx.circulant_graph(n, list(range(1, k // 2 + 1)))
+            assert is_isomorphic(G1, G2)
+
+        # When k is odd and n is even, the hkn_harary_graph(k,n) is
+        # the circulant_graph(n, list(range(1,(k+1)/2)) plus [n/2])
+        for (k, n) in [(3, 6), (5, 8), (7, 10)]:
+            G1 = hkn_harary_graph(k, n)
+            L = list(range(1, (k + 1) // 2))
+            L.append(n // 2)
+            G2 = nx.circulant_graph(n, L)
+            assert is_isomorphic(G1, G2)
+
+        # When k is odd and n is odd, the hkn_harary_graph(k,n) is
+        # the circulant_graph(n, list(range(1,(k+1)/2))) with
+        # n//2+1 edges added between node i and node i+n//2+1
+        for (k, n) in [(3, 5), (5, 9), (7, 11)]:
+            G1 = hkn_harary_graph(k, n)
+            G2 = nx.circulant_graph(n, list(range(1, (k + 1) // 2)))
+            eSet1 = set(G1.edges)
+            eSet2 = set(G2.edges)
+            eSet3 = set()
+            half = n // 2
+            for i in range(0, half + 1):
+                # add half+1 edges between i and i+half
+                eSet3.add((i, (i + half) % n))
+            assert eSet1 == eSet2 | eSet3
+
+        # Raise NetworkXError if k<1
+        k = 0
+        n = 0
+        pytest.raises(nx.NetworkXError, hkn_harary_graph, k, n)
+
+        # Raise NetworkXError if n<k+1
+        k = 6
+        n = 6
+        pytest.raises(nx.NetworkXError, hkn_harary_graph, k, n)