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author | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
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committer | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
commit | 4a52a71956a8d46fcb7294ac71734504bb09bcc2 (patch) | |
tree | ee3dc5af3b6313e921cd920906356f5d4febc4ed /.venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py | |
parent | cc961e04ba734dd72309fb548a2f97d67d578813 (diff) | |
download | gn-ai-master.tar.gz |
Diffstat (limited to '.venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py b/.venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py new file mode 100644 index 00000000..a81d6a69 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/networkx/algorithms/tests/test_polynomials.py @@ -0,0 +1,57 @@ +"""Unit tests for the :mod:`networkx.algorithms.polynomials` module.""" + +import pytest + +import networkx as nx + +sympy = pytest.importorskip("sympy") + + +# Mapping of input graphs to a string representation of their tutte polynomials +_test_tutte_graphs = { + nx.complete_graph(1): "1", + nx.complete_graph(4): "x**3 + 3*x**2 + 4*x*y + 2*x + y**3 + 3*y**2 + 2*y", + nx.cycle_graph(5): "x**4 + x**3 + x**2 + x + y", + nx.diamond_graph(): "x**3 + 2*x**2 + 2*x*y + x + y**2 + y", +} + +_test_chromatic_graphs = { + nx.complete_graph(1): "x", + nx.complete_graph(4): "x**4 - 6*x**3 + 11*x**2 - 6*x", + nx.cycle_graph(5): "x**5 - 5*x**4 + 10*x**3 - 10*x**2 + 4*x", + nx.diamond_graph(): "x**4 - 5*x**3 + 8*x**2 - 4*x", + nx.path_graph(5): "x**5 - 4*x**4 + 6*x**3 - 4*x**2 + x", +} + + +@pytest.mark.parametrize(("G", "expected"), _test_tutte_graphs.items()) +def test_tutte_polynomial(G, expected): + assert nx.tutte_polynomial(G).equals(expected) + + +@pytest.mark.parametrize("G", _test_tutte_graphs.keys()) +def test_tutte_polynomial_disjoint(G): + """Tutte polynomial factors into the Tutte polynomials of its components. + Verify this property with the disjoint union of two copies of the input graph. + """ + t_g = nx.tutte_polynomial(G) + H = nx.disjoint_union(G, G) + t_h = nx.tutte_polynomial(H) + assert sympy.simplify(t_g * t_g).equals(t_h) + + +@pytest.mark.parametrize(("G", "expected"), _test_chromatic_graphs.items()) +def test_chromatic_polynomial(G, expected): + assert nx.chromatic_polynomial(G).equals(expected) + + +@pytest.mark.parametrize("G", _test_chromatic_graphs.keys()) +def test_chromatic_polynomial_disjoint(G): + """Chromatic polynomial factors into the Chromatic polynomials of its + components. Verify this property with the disjoint union of two copies of + the input graph. + """ + x_g = nx.chromatic_polynomial(G) + H = nx.disjoint_union(G, G) + x_h = nx.chromatic_polynomial(H) + assert sympy.simplify(x_g * x_g).equals(x_h) |