Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/networkx/utils/tests/test_unionfind.py

42 lines
1.2 KiB
Python

import networkx as nx
def test_unionfind():
# Fixed by: 2cddd5958689bdecdcd89b91ac9aaf6ce0e4f6b8
# Previously (in 2.x), the UnionFind class could handle mixed types.
# But in Python 3.x, this causes a TypeError such as:
# TypeError: unorderable types: str() > int()
#
# Now we just make sure that no exception is raised.
x = nx.utils.UnionFind()
x.union(0, "a")
def test_subtree_union():
# See https://github.com/networkx/networkx/pull/3224
# (35db1b551ee65780794a357794f521d8768d5049).
# Test if subtree unions hare handled correctly by to_sets().
uf = nx.utils.UnionFind()
uf.union(1, 2)
uf.union(3, 4)
uf.union(4, 5)
uf.union(1, 5)
assert list(uf.to_sets()) == [{1, 2, 3, 4, 5}]
def test_unionfind_weights():
# Tests if weights are computed correctly with unions of many elements
uf = nx.utils.UnionFind()
uf.union(1, 4, 7)
uf.union(2, 5, 8)
uf.union(3, 6, 9)
uf.union(1, 2, 3, 4, 5, 6, 7, 8, 9)
assert uf.weights[uf[1]] == 9
def test_empty_union():
# Tests if a null-union does nothing.
uf = nx.utils.UnionFind((0, 1))
uf.union()
assert uf[0] == 0
assert uf[1] == 1