team-10/env/Lib/site-packages/scipy/sparse/csgraph/tests/test_traversal.py
2025-08-02 07:34:44 +02:00

148 lines
6 KiB
Python

import numpy as np
import pytest
from numpy.testing import assert_array_almost_equal
from scipy.sparse import csr_array, csr_matrix, coo_array, coo_matrix
from scipy.sparse.csgraph import (breadth_first_tree, depth_first_tree,
csgraph_to_dense, csgraph_from_dense, csgraph_masked_from_dense)
def test_graph_breadth_first():
csgraph = np.array([[0, 1, 2, 0, 0],
[1, 0, 0, 0, 3],
[2, 0, 0, 7, 0],
[0, 0, 7, 0, 1],
[0, 3, 0, 1, 0]])
csgraph = csgraph_from_dense(csgraph, null_value=0)
bfirst = np.array([[0, 1, 2, 0, 0],
[0, 0, 0, 0, 3],
[0, 0, 0, 7, 0],
[0, 0, 0, 0, 0],
[0, 0, 0, 0, 0]])
for directed in [True, False]:
bfirst_test = breadth_first_tree(csgraph, 0, directed)
assert_array_almost_equal(csgraph_to_dense(bfirst_test),
bfirst)
def test_graph_depth_first():
csgraph = np.array([[0, 1, 2, 0, 0],
[1, 0, 0, 0, 3],
[2, 0, 0, 7, 0],
[0, 0, 7, 0, 1],
[0, 3, 0, 1, 0]])
csgraph = csgraph_from_dense(csgraph, null_value=0)
dfirst = np.array([[0, 1, 0, 0, 0],
[0, 0, 0, 0, 3],
[0, 0, 0, 0, 0],
[0, 0, 7, 0, 0],
[0, 0, 0, 1, 0]])
for directed in [True, False]:
dfirst_test = depth_first_tree(csgraph, 0, directed)
assert_array_almost_equal(csgraph_to_dense(dfirst_test), dfirst)
def test_return_type():
from .._laplacian import laplacian
from .._min_spanning_tree import minimum_spanning_tree
np_csgraph = np.array([[0, 1, 2, 0, 0],
[1, 0, 0, 0, 3],
[2, 0, 0, 7, 0],
[0, 0, 7, 0, 1],
[0, 3, 0, 1, 0]])
csgraph = csr_array(np_csgraph)
assert isinstance(laplacian(csgraph), coo_array)
assert isinstance(minimum_spanning_tree(csgraph), csr_array)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_array)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_array)
csgraph = csgraph_from_dense(np_csgraph, null_value=0)
assert isinstance(csgraph, csr_array)
assert isinstance(laplacian(csgraph), coo_array)
assert isinstance(minimum_spanning_tree(csgraph), csr_array)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_array)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_array)
csgraph = csgraph_masked_from_dense(np_csgraph, null_value=0)
assert isinstance(csgraph, np.ma.MaskedArray)
assert csgraph._baseclass is np.ndarray
# laplacian doesnt work with masked arrays so not here
assert isinstance(minimum_spanning_tree(csgraph), csr_array)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_array)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_array)
# start of testing with matrix/spmatrix types
with np.testing.suppress_warnings() as sup:
sup.filter(DeprecationWarning, "the matrix subclass.*")
sup.filter(PendingDeprecationWarning, "the matrix subclass.*")
nm_csgraph = np.matrix([[0, 1, 2, 0, 0],
[1, 0, 0, 0, 3],
[2, 0, 0, 7, 0],
[0, 0, 7, 0, 1],
[0, 3, 0, 1, 0]])
csgraph = csr_matrix(nm_csgraph)
assert isinstance(laplacian(csgraph), coo_matrix)
assert isinstance(minimum_spanning_tree(csgraph), csr_matrix)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_matrix)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_matrix)
csgraph = csgraph_from_dense(nm_csgraph, null_value=0)
assert isinstance(csgraph, csr_matrix)
assert isinstance(laplacian(csgraph), coo_matrix)
assert isinstance(minimum_spanning_tree(csgraph), csr_matrix)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_matrix)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_matrix)
mm_csgraph = csgraph_masked_from_dense(nm_csgraph, null_value=0)
assert isinstance(mm_csgraph, np.ma.MaskedArray)
# laplacian doesnt work with masked arrays so not here
assert isinstance(minimum_spanning_tree(csgraph), csr_matrix)
for directed in [True, False]:
assert isinstance(depth_first_tree(csgraph, 0, directed), csr_matrix)
assert isinstance(breadth_first_tree(csgraph, 0, directed), csr_matrix)
# end of testing with matrix/spmatrix types
def test_graph_breadth_first_trivial_graph():
csgraph = np.array([[0]])
csgraph = csgraph_from_dense(csgraph, null_value=0)
bfirst = np.array([[0]])
for directed in [True, False]:
bfirst_test = breadth_first_tree(csgraph, 0, directed)
assert_array_almost_equal(csgraph_to_dense(bfirst_test), bfirst)
def test_graph_depth_first_trivial_graph():
csgraph = np.array([[0]])
csgraph = csgraph_from_dense(csgraph, null_value=0)
bfirst = np.array([[0]])
for directed in [True, False]:
bfirst_test = depth_first_tree(csgraph, 0, directed)
assert_array_almost_equal(csgraph_to_dense(bfirst_test),
bfirst)
@pytest.mark.parametrize('directed', [True, False])
@pytest.mark.parametrize('tree_func', [breadth_first_tree, depth_first_tree])
def test_int64_indices(tree_func, directed):
# See https://github.com/scipy/scipy/issues/18716
g = csr_array(([1], np.array([[0], [1]], dtype=np.int64)), shape=(2, 2))
assert g.indices.dtype == np.int64
tree = tree_func(g, 0, directed=directed)
assert_array_almost_equal(csgraph_to_dense(tree), [[0, 1], [0, 0]])