1 files changed, 230 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/networkx/generators/tests/test_degree_seq.py b/.venv/lib/python3.12/site-packages/networkx/generators/tests/test_degree_seq.py
new file mode 100644
index 00000000..39ed59a5
--- /dev/null
+++ b/.venv/lib/python3.12/site-packages/networkx/generators/tests/test_degree_seq.py
@@ -0,0 +1,230 @@
+import pytest
+
+import networkx as nx
+
+
+class TestConfigurationModel:
+    """Unit tests for the :func:`~networkx.configuration_model`
+    function.
+
+    """
+
+    def test_empty_degree_sequence(self):
+        """Tests that an empty degree sequence yields the null graph."""
+        G = nx.configuration_model([])
+        assert len(G) == 0
+
+    def test_degree_zero(self):
+        """Tests that a degree sequence of all zeros yields the empty
+        graph.
+
+        """
+        G = nx.configuration_model([0, 0, 0])
+        assert len(G) == 3
+        assert G.number_of_edges() == 0
+
+    def test_degree_sequence(self):
+        """Tests that the degree sequence of the generated graph matches
+        the input degree sequence.
+
+        """
+        deg_seq = [5, 3, 3, 3, 3, 2, 2, 2, 1, 1, 1]
+        G = nx.configuration_model(deg_seq, seed=12345678)
+        assert sorted((d for n, d in G.degree()), reverse=True) == [
+            5,
+            3,
+            3,
+            3,
+            3,
+            2,
+            2,
+            2,
+            1,
+            1,
+            1,
+        ]
+        assert sorted((d for n, d in G.degree(range(len(deg_seq)))), reverse=True) == [
+            5,
+            3,
+            3,
+            3,
+            3,
+            2,
+            2,
+            2,
+            1,
+            1,
+            1,
+        ]
+
+    def test_random_seed(self):
+        """Tests that each call with the same random seed generates the
+        same graph.
+
+        """
+        deg_seq = [3] * 12
+        G1 = nx.configuration_model(deg_seq, seed=1000)
+        G2 = nx.configuration_model(deg_seq, seed=1000)
+        assert nx.is_isomorphic(G1, G2)
+        G1 = nx.configuration_model(deg_seq, seed=10)
+        G2 = nx.configuration_model(deg_seq, seed=10)
+        assert nx.is_isomorphic(G1, G2)
+
+    def test_directed_disallowed(self):
+        """Tests that attempting to create a configuration model graph
+        using a directed graph yields an exception.
+
+        """
+        with pytest.raises(nx.NetworkXNotImplemented):
+            nx.configuration_model([], create_using=nx.DiGraph())
+
+    def test_odd_degree_sum(self):
+        """Tests that a degree sequence whose sum is odd yields an
+        exception.
+
+        """
+        with pytest.raises(nx.NetworkXError):
+            nx.configuration_model([1, 2])
+
+
+def test_directed_configuration_raise_unequal():
+    with pytest.raises(nx.NetworkXError):
+        zin = [5, 3, 3, 3, 3, 2, 2, 2, 1, 1]
+        zout = [5, 3, 3, 3, 3, 2, 2, 2, 1, 2]
+        nx.directed_configuration_model(zin, zout)
+
+
+def test_directed_configuration_model():
+    G = nx.directed_configuration_model([], [], seed=0)
+    assert len(G) == 0
+
+
+def test_simple_directed_configuration_model():
+    G = nx.directed_configuration_model([1, 1], [1, 1], seed=0)
+    assert len(G) == 2
+
+
+def test_expected_degree_graph_empty():
+    # empty graph has empty degree sequence
+    deg_seq = []
+    G = nx.expected_degree_graph(deg_seq)
+    assert dict(G.degree()) == {}
+
+
+def test_expected_degree_graph():
+    # test that fixed seed delivers the same graph
+    deg_seq = [3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3]
+    G1 = nx.expected_degree_graph(deg_seq, seed=1000)
+    assert len(G1) == 12
+
+    G2 = nx.expected_degree_graph(deg_seq, seed=1000)
+    assert nx.is_isomorphic(G1, G2)
+
+    G1 = nx.expected_degree_graph(deg_seq, seed=10)
+    G2 = nx.expected_degree_graph(deg_seq, seed=10)
+    assert nx.is_isomorphic(G1, G2)
+
+
+def test_expected_degree_graph_selfloops():
+    deg_seq = [3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3]
+    G1 = nx.expected_degree_graph(deg_seq, seed=1000, selfloops=False)
+    G2 = nx.expected_degree_graph(deg_seq, seed=1000, selfloops=False)
+    assert nx.is_isomorphic(G1, G2)
+    assert len(G1) == 12
+
+
+def test_expected_degree_graph_skew():
+    deg_seq = [10, 2, 2, 2, 2]
+    G1 = nx.expected_degree_graph(deg_seq, seed=1000)
+    G2 = nx.expected_degree_graph(deg_seq, seed=1000)
+    assert nx.is_isomorphic(G1, G2)
+    assert len(G1) == 5
+
+
+def test_havel_hakimi_construction():
+    G = nx.havel_hakimi_graph([])
+    assert len(G) == 0
+
+    z = [1000, 3, 3, 3, 3, 2, 2, 2, 1, 1, 1]
+    pytest.raises(nx.NetworkXError, nx.havel_hakimi_graph, z)
+    z = ["A", 3, 3, 3, 3, 2, 2, 2, 1, 1, 1]
+    pytest.raises(nx.NetworkXError, nx.havel_hakimi_graph, z)
+
+    z = [5, 4, 3, 3, 3, 2, 2, 2]
+    G = nx.havel_hakimi_graph(z)
+    G = nx.configuration_model(z)
+    z = [6, 5, 4, 4, 2, 1, 1, 1]
+    pytest.raises(nx.NetworkXError, nx.havel_hakimi_graph, z)
+
+    z = [10, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2]
+
+    G = nx.havel_hakimi_graph(z)
+
+    pytest.raises(nx.NetworkXError, nx.havel_hakimi_graph, z, create_using=nx.DiGraph())
+
+
+def test_directed_havel_hakimi():
+    # Test range of valid directed degree sequences
+    n, r = 100, 10
+    p = 1.0 / r
+    for i in range(r):
+        G1 = nx.erdos_renyi_graph(n, p * (i + 1), None, True)
+        din1 = [d for n, d in G1.in_degree()]
+        dout1 = [d for n, d in G1.out_degree()]
+        G2 = nx.directed_havel_hakimi_graph(din1, dout1)
+        din2 = [d for n, d in G2.in_degree()]
+        dout2 = [d for n, d in G2.out_degree()]
+        assert sorted(din1) == sorted(din2)
+        assert sorted(dout1) == sorted(dout2)
+
+    # Test non-graphical sequence
+    dout = [1000, 3, 3, 3, 3, 2, 2, 2, 1, 1, 1]
+    din = [103, 102, 102, 102, 102, 102, 102, 102, 102, 102]
+    pytest.raises(nx.exception.NetworkXError, nx.directed_havel_hakimi_graph, din, dout)
+    # Test valid sequences
+    dout = [1, 1, 1, 1, 1, 2, 2, 2, 3, 4]
+    din = [2, 2, 2, 2, 2, 2, 2, 2, 0, 2]
+    G2 = nx.directed_havel_hakimi_graph(din, dout)
+    dout2 = (d for n, d in G2.out_degree())
+    din2 = (d for n, d in G2.in_degree())
+    assert sorted(dout) == sorted(dout2)
+    assert sorted(din) == sorted(din2)
+    # Test unequal sums
+    din = [2, 2, 2, 2, 2, 2, 2, 2, 2, 2]
+    pytest.raises(nx.exception.NetworkXError, nx.directed_havel_hakimi_graph, din, dout)
+    # Test for negative values
+    din = [2, 2, 2, 2, 2, 2, 2, 2, 2, 2, -2]
+    pytest.raises(nx.exception.NetworkXError, nx.directed_havel_hakimi_graph, din, dout)
+
+
+def test_degree_sequence_tree():
+    z = [1, 1, 1, 1, 1, 2, 2, 2, 3, 4]
+    G = nx.degree_sequence_tree(z)
+    assert len(G) == len(z)
+    assert len(list(G.edges())) == sum(z) / 2
+
+    pytest.raises(
+        nx.NetworkXError, nx.degree_sequence_tree, z, create_using=nx.DiGraph()
+    )
+
+    z = [1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 4]
+    pytest.raises(nx.NetworkXError, nx.degree_sequence_tree, z)
+
+
+def test_random_degree_sequence_graph():
+    d = [1, 2, 2, 3]
+    G = nx.random_degree_sequence_graph(d, seed=42)
+    assert d == sorted(d for n, d in G.degree())
+
+
+def test_random_degree_sequence_graph_raise():
+    z = [1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 4]
+    pytest.raises(nx.NetworkXUnfeasible, nx.random_degree_sequence_graph, z)
+
+
+def test_random_degree_sequence_large():
+    G1 = nx.fast_gnp_random_graph(100, 0.1, seed=42)
+    d1 = (d for n, d in G1.degree())
+    G2 = nx.random_degree_sequence_graph(d1, seed=42)
+    d2 = (d for n, d in G2.degree())
+    assert sorted(d1) == sorted(d2)