tykayn/book-generator-orgmode
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

up follow livre

Browse source
This commit is contained in:
Tykayn 2025-08-30 18:14:14 +02:00 • committed by tykayn
parent 70a5c3465c
commit cffb31c1ef
12198 changed files with 2562132 additions and 35 deletions
Download patch file Download diff file Expand all files Collapse all files

210
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/__init__.py Normal file
View file

@ -0,0 +1,210 @@
r"""
Compressed sparse graph routines (:mod:`scipy.sparse.csgraph`)
==============================================================
.. currentmodule:: scipy.sparse.csgraph
Fast graph algorithms based on sparse matrix representations.
Contents
--------
.. autosummary::
:toctree: generated/
connected_components -- determine connected components of a graph
laplacian -- compute the laplacian of a graph
shortest_path -- compute the shortest path between points on a positive graph
dijkstra -- use Dijkstra's algorithm for shortest path
floyd_warshall -- use the Floyd-Warshall algorithm for shortest path
bellman_ford -- use the Bellman-Ford algorithm for shortest path
johnson -- use Johnson's algorithm for shortest path
yen -- use Yen's algorithm for K-shortest paths between to nodes.
breadth_first_order -- compute a breadth-first order of nodes
depth_first_order -- compute a depth-first order of nodes
breadth_first_tree -- construct the breadth-first tree from a given node
depth_first_tree -- construct a depth-first tree from a given node
minimum_spanning_tree -- construct the minimum spanning tree of a graph
reverse_cuthill_mckee -- compute permutation for reverse Cuthill-McKee ordering
maximum_flow -- solve the maximum flow problem for a graph
maximum_bipartite_matching -- compute a maximum matching of a bipartite graph
min_weight_full_bipartite_matching - compute a minimum weight full matching of a bipartite graph
structural_rank -- compute the structural rank of a graph
NegativeCycleError
.. autosummary::
:toctree: generated/
construct_dist_matrix
csgraph_from_dense
csgraph_from_masked
csgraph_masked_from_dense
csgraph_to_dense
csgraph_to_masked
reconstruct_path
Graph Representations
---------------------
This module uses graphs which are stored in a matrix format. A
graph with N nodes can be represented by an (N x N) adjacency matrix G.
If there is a connection from node i to node j, then G[i, j] = w, where
w is the weight of the connection. For nodes i and j which are
not connected, the value depends on the representation:
- for dense array representations, non-edges are represented by
G[i, j] = 0, infinity, or NaN.
- for dense masked representations (of type np.ma.MaskedArray), non-edges
are represented by masked values. This can be useful when graphs with
zero-weight edges are desired.
- for sparse array representations, non-edges are represented by
non-entries in the matrix. This sort of sparse representation also
allows for edges with zero weights.
As a concrete example, imagine that you would like to represent the following
undirected graph::
G
(0)
/ \
1 2
/ \
(2) (1)
This graph has three nodes, where node 0 and 1 are connected by an edge of
weight 2, and nodes 0 and 2 are connected by an edge of weight 1.
We can construct the dense, masked, and sparse representations as follows,
keeping in mind that an undirected graph is represented by a symmetric matrix::
>>> import numpy as np
>>> G_dense = np.array([[0, 2, 1],
... [2, 0, 0],
... [1, 0, 0]])
>>> G_masked = np.ma.masked_values(G_dense, 0)
>>> from scipy.sparse import csr_array
>>> G_sparse = csr_array(G_dense)
This becomes more difficult when zero edges are significant. For example,
consider the situation when we slightly modify the above graph::
G2
(0)
/ \
0 2
/ \
(2) (1)
This is identical to the previous graph, except nodes 0 and 2 are connected
by an edge of zero weight. In this case, the dense representation above
leads to ambiguities: how can non-edges be represented if zero is a meaningful
value? In this case, either a masked or sparse representation must be used
to eliminate the ambiguity::
>>> import numpy as np
>>> G2_data = np.array([[np.inf, 2, 0 ],
... [2, np.inf, np.inf],
... [0, np.inf, np.inf]])
>>> G2_masked = np.ma.masked_invalid(G2_data)
>>> from scipy.sparse.csgraph import csgraph_from_dense
>>> # G2_sparse = csr_array(G2_data) would give the wrong result
>>> G2_sparse = csgraph_from_dense(G2_data, null_value=np.inf)
>>> G2_sparse.data
array([ 2., 0., 2., 0.])
Here we have used a utility routine from the csgraph submodule in order to
convert the dense representation to a sparse representation which can be
understood by the algorithms in submodule. By viewing the data array, we
can see that the zero values are explicitly encoded in the graph.
Directed vs. undirected
^^^^^^^^^^^^^^^^^^^^^^^
Matrices may represent either directed or undirected graphs. This is
specified throughout the csgraph module by a boolean keyword. Graphs are
assumed to be directed by default. In a directed graph, traversal from node
i to node j can be accomplished over the edge G[i, j], but not the edge
G[j, i]. Consider the following dense graph::
>>> import numpy as np
>>> G_dense = np.array([[0, 1, 0],
... [2, 0, 3],
... [0, 4, 0]])
When ``directed=True`` we get the graph::
---1--> ---3-->
(0) (1) (2)
<--2--- <--4---
In a non-directed graph, traversal from node i to node j can be
accomplished over either G[i, j] or G[j, i]. If both edges are not null,
and the two have unequal weights, then the smaller of the two is used.
So for the same graph, when ``directed=False`` we get the graph::
(0)--1--(1)--3--(2)
Note that a symmetric matrix will represent an undirected graph, regardless
of whether the 'directed' keyword is set to True or False. In this case,
using ``directed=True`` generally leads to more efficient computation.
The routines in this module accept as input either scipy.sparse representations
(csr, csc, or lil format), masked representations, or dense representations
with non-edges indicated by zeros, infinities, and NaN entries.
""" # noqa: E501
__docformat__ = "restructuredtext en"
__all__ = ['connected_components',
'laplacian',
'shortest_path',
'floyd_warshall',
'dijkstra',
'bellman_ford',
'johnson',
'yen',
'breadth_first_order',
'depth_first_order',
'breadth_first_tree',
'depth_first_tree',
'minimum_spanning_tree',
'reverse_cuthill_mckee',
'maximum_flow',
'maximum_bipartite_matching',
'min_weight_full_bipartite_matching',
'structural_rank',
'construct_dist_matrix',
'reconstruct_path',
'csgraph_masked_from_dense',
'csgraph_from_dense',
'csgraph_from_masked',
'csgraph_to_dense',
'csgraph_to_masked',
'NegativeCycleError']
from ._laplacian import laplacian
from ._shortest_path import (
shortest_path, floyd_warshall, dijkstra, bellman_ford, johnson, yen,
NegativeCycleError
)
from ._traversal import (
breadth_first_order, depth_first_order, breadth_first_tree,
depth_first_tree, connected_components
)
from ._min_spanning_tree import minimum_spanning_tree
from ._flow import maximum_flow
from ._matching import (
maximum_bipartite_matching, min_weight_full_bipartite_matching
)
from ._reordering import reverse_cuthill_mckee, structural_rank
from ._tools import (
construct_dist_matrix, reconstruct_path, csgraph_from_dense,
csgraph_to_dense, csgraph_masked_from_dense, csgraph_from_masked,
csgraph_to_masked
)
from scipy._lib._testutils import PytestTester
test = PytestTester(__name__)
del PytestTester

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/__pycache__/__init__.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/__pycache__/_laplacian.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/__pycache__/_validation.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_flow.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

563
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_laplacian.py Normal file
View file

@ -0,0 +1,563 @@
"""
Laplacian of a compressed-sparse graph
"""
import numpy as np
from scipy.sparse import issparse
from scipy.sparse.linalg import LinearOperator
from scipy.sparse._sputils import convert_pydata_sparse_to_scipy, is_pydata_spmatrix
###############################################################################
# Graph laplacian
def laplacian(
csgraph,
normed=False,
return_diag=False,
use_out_degree=False,
*,
copy=True,
form="array",
dtype=None,
symmetrized=False,
):
"""
Return the Laplacian of a directed graph.
Parameters
----------
csgraph : array_like or sparse array or matrix, 2 dimensions
compressed-sparse graph, with shape (N, N).
normed : bool, optional
If True, then compute symmetrically normalized Laplacian.
Default: False.
return_diag : bool, optional
If True, then also return an array related to vertex degrees.
Default: False.
use_out_degree : bool, optional
If True, then use out-degree instead of in-degree.
This distinction matters only if the graph is asymmetric.
Default: False.
copy: bool, optional
If False, then change `csgraph` in place if possible,
avoiding doubling the memory use.
Default: True, for backward compatibility.
form: 'array', or 'function', or 'lo'
Determines the format of the output Laplacian:
* 'array' is a numpy array;
* 'function' is a pointer to evaluating the Laplacian-vector
or Laplacian-matrix product;
* 'lo' results in the format of the `LinearOperator`.
Choosing 'function' or 'lo' always avoids doubling
the memory use, ignoring `copy` value.
Default: 'array', for backward compatibility.
dtype: None or one of numeric numpy dtypes, optional
The dtype of the output. If ``dtype=None``, the dtype of the
output matches the dtype of the input csgraph, except for
the case ``normed=True`` and integer-like csgraph, where
the output dtype is 'float' allowing accurate normalization,
but dramatically increasing the memory use.
Default: None, for backward compatibility.
symmetrized: bool, optional
If True, then the output Laplacian is symmetric/Hermitian.
The symmetrization is done by ``csgraph + csgraph.T.conj``
without dividing by 2 to preserve integer dtypes if possible
prior to the construction of the Laplacian.
The symmetrization will increase the memory footprint of
sparse matrices unless the sparsity pattern is symmetric or
`form` is 'function' or 'lo'.
Default: False, for backward compatibility.
Returns
-------
lap : ndarray, or sparse array or matrix, or `LinearOperator`
The N x N Laplacian of csgraph. It will be a NumPy array (dense)
if the input was dense, or a sparse array otherwise, or
the format of a function or `LinearOperator` if
`form` equals 'function' or 'lo', respectively.
diag : ndarray, optional
The length-N main diagonal of the Laplacian matrix.
For the normalized Laplacian, this is the array of square roots
of vertex degrees or 1 if the degree is zero.
Notes
-----
The Laplacian matrix of a graph is sometimes referred to as the
"Kirchhoff matrix" or just the "Laplacian", and is useful in many
parts of spectral graph theory.
In particular, the eigen-decomposition of the Laplacian can give
insight into many properties of the graph, e.g.,
is commonly used for spectral data embedding and clustering.
The constructed Laplacian doubles the memory use if ``copy=True`` and
``form="array"`` which is the default.
Choosing ``copy=False`` has no effect unless ``form="array"``
or the matrix is sparse in the ``coo`` format, or dense array, except
for the integer input with ``normed=True`` that forces the float output.
Sparse input is reformatted into ``coo`` if ``form="array"``,
which is the default.
If the input adjacency matrix is not symmetric, the Laplacian is
also non-symmetric unless ``symmetrized=True`` is used.
Diagonal entries of the input adjacency matrix are ignored and
replaced with zeros for the purpose of normalization where ``normed=True``.
The normalization uses the inverse square roots of row-sums of the input
adjacency matrix, and thus may fail if the row-sums contain
negative or complex with a non-zero imaginary part values.
The normalization is symmetric, making the normalized Laplacian also
symmetric if the input csgraph was symmetric.
References
----------
.. [1] Laplacian matrix. https://en.wikipedia.org/wiki/Laplacian_matrix
Examples
--------
>>> import numpy as np
>>> from scipy.sparse import csgraph
Our first illustration is the symmetric graph
>>> G = np.arange(4) * np.arange(4)[:, np.newaxis]
>>> G
array([[0, 0, 0, 0],
[0, 1, 2, 3],
[0, 2, 4, 6],
[0, 3, 6, 9]])
and its symmetric Laplacian matrix
>>> csgraph.laplacian(G)
array([[ 0, 0, 0, 0],
[ 0, 5, -2, -3],
[ 0, -2, 8, -6],
[ 0, -3, -6, 9]])
The non-symmetric graph
>>> G = np.arange(9).reshape(3, 3)
>>> G
array([[0, 1, 2],
[3, 4, 5],
[6, 7, 8]])
has different row- and column sums, resulting in two varieties
of the Laplacian matrix, using an in-degree, which is the default
>>> L_in_degree = csgraph.laplacian(G)
>>> L_in_degree
array([[ 9, -1, -2],
[-3, 8, -5],
[-6, -7, 7]])
or alternatively an out-degree
>>> L_out_degree = csgraph.laplacian(G, use_out_degree=True)
>>> L_out_degree
array([[ 3, -1, -2],
[-3, 8, -5],
[-6, -7, 13]])
Constructing a symmetric Laplacian matrix, one can add the two as
>>> L_in_degree + L_out_degree.T
array([[ 12, -4, -8],
[ -4, 16, -12],
[ -8, -12, 20]])
or use the ``symmetrized=True`` option
>>> csgraph.laplacian(G, symmetrized=True)
array([[ 12, -4, -8],
[ -4, 16, -12],
[ -8, -12, 20]])
that is equivalent to symmetrizing the original graph
>>> csgraph.laplacian(G + G.T)
array([[ 12, -4, -8],
[ -4, 16, -12],
[ -8, -12, 20]])
The goal of normalization is to make the non-zero diagonal entries
of the Laplacian matrix to be all unit, also scaling off-diagonal
entries correspondingly. The normalization can be done manually, e.g.,
>>> G = np.array([[0, 1, 1], [1, 0, 1], [1, 1, 0]])
>>> L, d = csgraph.laplacian(G, return_diag=True)
>>> L
array([[ 2, -1, -1],
[-1, 2, -1],
[-1, -1, 2]])
>>> d
array([2, 2, 2])
>>> scaling = np.sqrt(d)
>>> scaling
array([1.41421356, 1.41421356, 1.41421356])
>>> (1/scaling)*L*(1/scaling)
array([[ 1. , -0.5, -0.5],
[-0.5, 1. , -0.5],
[-0.5, -0.5, 1. ]])
Or using ``normed=True`` option
>>> L, d = csgraph.laplacian(G, return_diag=True, normed=True)
>>> L
array([[ 1. , -0.5, -0.5],
[-0.5, 1. , -0.5],
[-0.5, -0.5, 1. ]])
which now instead of the diagonal returns the scaling coefficients
>>> d
array([1.41421356, 1.41421356, 1.41421356])
Zero scaling coefficients are substituted with 1s, where scaling
has thus no effect, e.g.,
>>> G = np.array([[0, 0, 0], [0, 0, 1], [0, 1, 0]])
>>> G
array([[0, 0, 0],
[0, 0, 1],
[0, 1, 0]])
>>> L, d = csgraph.laplacian(G, return_diag=True, normed=True)
>>> L
array([[ 0., -0., -0.],
[-0., 1., -1.],
[-0., -1., 1.]])
>>> d
array([1., 1., 1.])
Only the symmetric normalization is implemented, resulting
in a symmetric Laplacian matrix if and only if its graph is symmetric
and has all non-negative degrees, like in the examples above.
The output Laplacian matrix is by default a dense array or a sparse
array or matrix inferring its class, shape, format, and dtype from
the input graph matrix:
>>> G = np.array([[0, 1, 1], [1, 0, 1], [1, 1, 0]]).astype(np.float32)
>>> G
array([[0., 1., 1.],
[1., 0., 1.],
[1., 1., 0.]], dtype=float32)
>>> csgraph.laplacian(G)
array([[ 2., -1., -1.],
[-1., 2., -1.],
[-1., -1., 2.]], dtype=float32)
but can alternatively be generated matrix-free as a LinearOperator:
>>> L = csgraph.laplacian(G, form="lo")
>>> L
<3x3 _CustomLinearOperator with dtype=float32>
>>> L(np.eye(3))
array([[ 2., -1., -1.],
[-1., 2., -1.],
[-1., -1., 2.]])
or as a lambda-function:
>>> L = csgraph.laplacian(G, form="function")
>>> L
<function _laplace.<locals>.<lambda> at 0x0000012AE6F5A598>
>>> L(np.eye(3))
array([[ 2., -1., -1.],
[-1., 2., -1.],
[-1., -1., 2.]])
The Laplacian matrix is used for
spectral data clustering and embedding
as well as for spectral graph partitioning.
Our final example illustrates the latter
for a noisy directed linear graph.
>>> from scipy.sparse import diags_array, random_array
>>> from scipy.sparse.linalg import lobpcg
Create a directed linear graph with ``N=35`` vertices
using a sparse adjacency matrix ``G``:
>>> N = 35
>>> G = diags_array(np.ones(N - 1), offsets=1, format="csr")
Fix a random seed ``rng`` and add a random sparse noise to the graph ``G``:
>>> rng = np.random.default_rng()
>>> G += 1e-2 * random_array((N, N), density=0.1, rng=rng)
Set initial approximations for eigenvectors:
>>> X = rng.random((N, 2))
The constant vector of ones is always a trivial eigenvector
of the non-normalized Laplacian to be filtered out:
>>> Y = np.ones((N, 1))
Alternating (1) the sign of the graph weights allows determining
labels for spectral max- and min- cuts in a single loop.
Since the graph is undirected, the option ``symmetrized=True``
must be used in the construction of the Laplacian.
The option ``normed=True`` cannot be used in (2) for the negative weights
here as the symmetric normalization evaluates square roots.
The option ``form="lo"`` in (2) is matrix-free, i.e., guarantees
a fixed memory footprint and read-only access to the graph.
Calling the eigenvalue solver ``lobpcg`` (3) computes the Fiedler vector
that determines the labels as the signs of its components in (5).
Since the sign in an eigenvector is not deterministic and can flip,
we fix the sign of the first component to be always +1 in (4).
>>> for cut in ["max", "min"]:
... G = -G # 1.
... L = csgraph.laplacian(G, symmetrized=True, form="lo") # 2.
... _, eves = lobpcg(L, X, Y=Y, largest=False, tol=1e-2) # 3.
... eves *= np.sign(eves[0, 0]) # 4.
... print(cut + "-cut labels:\\n", 1 * (eves[:, 0]>0)) # 5.
max-cut labels:
[1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1]
min-cut labels:
[1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
As anticipated for a (slightly noisy) linear graph,
the max-cut strips all the edges of the graph coloring all
odd vertices into one color and all even vertices into another one,
while the balanced min-cut partitions the graph
in the middle by deleting a single edge.
Both determined partitions are optimal.
"""
is_pydata_sparse = is_pydata_spmatrix(csgraph)
if is_pydata_sparse:
pydata_sparse_cls = csgraph.__class__
csgraph = convert_pydata_sparse_to_scipy(csgraph)
if csgraph.ndim != 2 or csgraph.shape[0] != csgraph.shape[1]:
raise ValueError('csgraph must be a square matrix or array')
if normed and (
np.issubdtype(csgraph.dtype, np.signedinteger)
or np.issubdtype(csgraph.dtype, np.uint)
):
csgraph = csgraph.astype(np.float64)
if form == "array":
create_lap = (
_laplacian_sparse if issparse(csgraph) else _laplacian_dense
)
else:
create_lap = (
_laplacian_sparse_flo
if issparse(csgraph)
else _laplacian_dense_flo
)
degree_axis = 1 if use_out_degree else 0
lap, d = create_lap(
csgraph,
normed=normed,
axis=degree_axis,
copy=copy,
form=form,
dtype=dtype,
symmetrized=symmetrized,
)
if is_pydata_sparse:
lap = pydata_sparse_cls.from_scipy_sparse(lap)
if return_diag:
return lap, d
return lap
def _setdiag_dense(m, d):
step = len(d) + 1
m.flat[::step] = d
def _laplace(m, d):
return lambda v: v * d[:, np.newaxis] - m @ v
def _laplace_normed(m, d, nd):
laplace = _laplace(m, d)
return lambda v: nd[:, np.newaxis] * laplace(v * nd[:, np.newaxis])
def _laplace_sym(m, d):
return (
lambda v: v * d[:, np.newaxis]
- m @ v
- np.transpose(np.conjugate(np.transpose(np.conjugate(v)) @ m))
)
def _laplace_normed_sym(m, d, nd):
laplace_sym = _laplace_sym(m, d)
return lambda v: nd[:, np.newaxis] * laplace_sym(v * nd[:, np.newaxis])
def _linearoperator(mv, shape, dtype):
return LinearOperator(matvec=mv, matmat=mv, shape=shape, dtype=dtype)
def _laplacian_sparse_flo(graph, normed, axis, copy, form, dtype, symmetrized):
# The keyword argument `copy` is unused and has no effect here.
del copy
if dtype is None:
dtype = graph.dtype
graph_sum = np.asarray(graph.sum(axis=axis)).ravel()
graph_diagonal = graph.diagonal()
diag = graph_sum - graph_diagonal
if symmetrized:
graph_sum += np.asarray(graph.sum(axis=1 - axis)).ravel()
diag = graph_sum - graph_diagonal - graph_diagonal
if normed:
isolated_node_mask = diag == 0
w = np.where(isolated_node_mask, 1, np.sqrt(diag))
if symmetrized:
md = _laplace_normed_sym(graph, graph_sum, 1.0 / w)
else:
md = _laplace_normed(graph, graph_sum, 1.0 / w)
if form == "function":
return md, w.astype(dtype, copy=False)
elif form == "lo":
m = _linearoperator(md, shape=graph.shape, dtype=dtype)
return m, w.astype(dtype, copy=False)
else:
raise ValueError(f"Invalid form: {form!r}")
else:
if symmetrized:
md = _laplace_sym(graph, graph_sum)
else:
md = _laplace(graph, graph_sum)
if form == "function":
return md, diag.astype(dtype, copy=False)
elif form == "lo":
m = _linearoperator(md, shape=graph.shape, dtype=dtype)
return m, diag.astype(dtype, copy=False)
else:
raise ValueError(f"Invalid form: {form!r}")
def _laplacian_sparse(graph, normed, axis, copy, form, dtype, symmetrized):
# The keyword argument `form` is unused and has no effect here.
del form
if dtype is None:
dtype = graph.dtype
needs_copy = False
if graph.format in ('lil', 'dok'):
m = graph.tocoo()
else:
m = graph
if copy:
needs_copy = True
if symmetrized:
m += m.T.conj()
w = np.asarray(m.sum(axis=axis)).ravel() - m.diagonal()
if normed:
m = m.tocoo(copy=needs_copy)
isolated_node_mask = (w == 0)
w = np.where(isolated_node_mask, 1, np.sqrt(w))
m.data /= w[m.row]
m.data /= w[m.col]
m.data *= -1
m.setdiag(1 - isolated_node_mask)
else:
if m.format == 'dia':
m = m.copy()
else:
m = m.tocoo(copy=needs_copy)
m.data *= -1
m.setdiag(w)
return m.astype(dtype, copy=False), w.astype(dtype)
def _laplacian_dense_flo(graph, normed, axis, copy, form, dtype, symmetrized):
if copy:
m = np.array(graph)
else:
m = np.asarray(graph)
if dtype is None:
dtype = m.dtype
graph_sum = m.sum(axis=axis)
graph_diagonal = m.diagonal()
diag = graph_sum - graph_diagonal
if symmetrized:
graph_sum += m.sum(axis=1 - axis)
diag = graph_sum - graph_diagonal - graph_diagonal
if normed:
isolated_node_mask = diag == 0
w = np.where(isolated_node_mask, 1, np.sqrt(diag))
if symmetrized:
md = _laplace_normed_sym(m, graph_sum, 1.0 / w)
else:
md = _laplace_normed(m, graph_sum, 1.0 / w)
if form == "function":
return md, w.astype(dtype, copy=False)
elif form == "lo":
m = _linearoperator(md, shape=graph.shape, dtype=dtype)
return m, w.astype(dtype, copy=False)
else:
raise ValueError(f"Invalid form: {form!r}")
else:
if symmetrized:
md = _laplace_sym(m, graph_sum)
else:
md = _laplace(m, graph_sum)
if form == "function":
return md, diag.astype(dtype, copy=False)
elif form == "lo":
m = _linearoperator(md, shape=graph.shape, dtype=dtype)
return m, diag.astype(dtype, copy=False)
else:
raise ValueError(f"Invalid form: {form!r}")
def _laplacian_dense(graph, normed, axis, copy, form, dtype, symmetrized):
if form != "array":
raise ValueError(f'{form!r} must be "array"')
if dtype is None:
dtype = graph.dtype
if copy:
m = np.array(graph)
else:
m = np.asarray(graph)
if dtype is None:
dtype = m.dtype
if symmetrized:
m += m.T.conj()
np.fill_diagonal(m, 0)
w = m.sum(axis=axis)
if normed:
isolated_node_mask = (w == 0)
w = np.where(isolated_node_mask, 1, np.sqrt(w))
m /= w
m /= w[:, np.newaxis]
m *= -1
_setdiag_dense(m, 1 - isolated_node_mask)
else:
m *= -1
_setdiag_dense(m, w)
return m.astype(dtype, copy=False), w.astype(dtype, copy=False)

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_matching.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_min_spanning_tree.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_reordering.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_shortest_path.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_tools.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_traversal.cpython-313-x86_64-linux-gnu.so Executable file
View file

Binary file not shown.

66
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/_validation.py Normal file
View file

@ -0,0 +1,66 @@
import numpy as np
from scipy.sparse import issparse
from scipy.sparse._sputils import convert_pydata_sparse_to_scipy
from scipy.sparse.csgraph._tools import (
csgraph_to_dense, csgraph_from_dense,
csgraph_masked_from_dense, csgraph_from_masked
)
DTYPE = np.float64
def validate_graph(csgraph, directed, dtype=DTYPE,
csr_output=True, dense_output=True,
copy_if_dense=False, copy_if_sparse=False,
null_value_in=0, null_value_out=np.inf,
infinity_null=True, nan_null=True):
"""Routine for validation and conversion of csgraph inputs"""
if not (csr_output or dense_output):
raise ValueError("Internal: dense or csr output must be true")
accept_fv = [null_value_in]
if infinity_null:
accept_fv.append(np.inf)
if nan_null:
accept_fv.append(np.nan)
csgraph = convert_pydata_sparse_to_scipy(csgraph, accept_fv=accept_fv)
# if undirected and csc storage, then transposing in-place
# is quicker than later converting to csr.
if (not directed) and issparse(csgraph) and csgraph.format == "csc":
csgraph = csgraph.T
if issparse(csgraph):
if csr_output:
csgraph = csgraph.tocsr(copy=copy_if_sparse).astype(DTYPE, copy=False)
else:
csgraph = csgraph_to_dense(csgraph, null_value=null_value_out)
elif np.ma.isMaskedArray(csgraph):
if dense_output:
mask = csgraph.mask
csgraph = np.array(csgraph.data, dtype=DTYPE, copy=copy_if_dense)
csgraph[mask] = null_value_out
else:
csgraph = csgraph_from_masked(csgraph)
else:
if dense_output:
csgraph = csgraph_masked_from_dense(csgraph,
copy=copy_if_dense,
null_value=null_value_in,
nan_null=nan_null,
infinity_null=infinity_null)
mask = csgraph.mask
csgraph = np.asarray(csgraph.data, dtype=DTYPE)
csgraph[mask] = null_value_out
else:
csgraph = csgraph_from_dense(csgraph, null_value=null_value_in,
infinity_null=infinity_null,
nan_null=nan_null)
if csgraph.ndim != 2:
raise ValueError("compressed-sparse graph must be 2-D")
if csgraph.shape[0] != csgraph.shape[1]:
raise ValueError("compressed-sparse graph must be shape (N, N)")
return csgraph

0
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__init__.py Normal file
View file

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/__init__.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_connected_components.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_conversions.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_flow.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_graph_laplacian.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_matching.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_pydata_sparse.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_reordering.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_shortest_path.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_spanning_tree.cpython-313.pyc Normal file
View file

Binary file not shown.

BIN
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/__pycache__/test_traversal.cpython-313.pyc Normal file
View file

Binary file not shown.

119
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_connected_components.py Normal file
View file

@ -0,0 +1,119 @@
import numpy as np
from numpy.testing import assert_equal, assert_array_almost_equal
from scipy.sparse import csgraph, csr_array
def test_weak_connections():
Xde = np.array([[0, 1, 0],
[0, 0, 0],
[0, 0, 0]])
Xsp = csgraph.csgraph_from_dense(Xde, null_value=0)
for X in Xsp, Xde:
n_components, labels =\
csgraph.connected_components(X, directed=True,
connection='weak')
assert_equal(n_components, 2)
assert_array_almost_equal(labels, [0, 0, 1])
def test_strong_connections():
X1de = np.array([[0, 1, 0],
[0, 0, 0],
[0, 0, 0]])
X2de = X1de + X1de.T
X1sp = csgraph.csgraph_from_dense(X1de, null_value=0)
X2sp = csgraph.csgraph_from_dense(X2de, null_value=0)
for X in X1sp, X1de:
n_components, labels =\
csgraph.connected_components(X, directed=True,
connection='strong')
assert_equal(n_components, 3)
labels.sort()
assert_array_almost_equal(labels, [0, 1, 2])
for X in X2sp, X2de:
n_components, labels =\
csgraph.connected_components(X, directed=True,
connection='strong')
assert_equal(n_components, 2)
labels.sort()
assert_array_almost_equal(labels, [0, 0, 1])
def test_strong_connections2():
X = np.array([[0, 0, 0, 0, 0, 0],
[1, 0, 1, 0, 0, 0],
[0, 0, 0, 1, 0, 0],
[0, 0, 1, 0, 1, 0],
[0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0]])
n_components, labels =\
csgraph.connected_components(X, directed=True,
connection='strong')
assert_equal(n_components, 5)
labels.sort()
assert_array_almost_equal(labels, [0, 1, 2, 2, 3, 4])
def test_weak_connections2():
X = np.array([[0, 0, 0, 0, 0, 0],
[1, 0, 0, 0, 0, 0],
[0, 0, 0, 1, 0, 0],
[0, 0, 1, 0, 1, 0],
[0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0]])
n_components, labels =\
csgraph.connected_components(X, directed=True,
connection='weak')
assert_equal(n_components, 2)
labels.sort()
assert_array_almost_equal(labels, [0, 0, 1, 1, 1, 1])
def test_ticket1876():
# Regression test: this failed in the original implementation
# There should be two strongly-connected components; previously gave one
g = np.array([[0, 1, 1, 0],
[1, 0, 0, 1],
[0, 0, 0, 1],
[0, 0, 1, 0]])
n_components, labels = csgraph.connected_components(g, connection='strong')
assert_equal(n_components, 2)
assert_equal(labels[0], labels[1])
assert_equal(labels[2], labels[3])
def test_fully_connected_graph():
# Fully connected dense matrices raised an exception.
# https://github.com/scipy/scipy/issues/3818
g = np.ones((4, 4))
n_components, labels = csgraph.connected_components(g)
assert_equal(n_components, 1)
def test_int64_indices_undirected():
# 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
n, labels = csgraph.connected_components(g, directed=False)
assert n == 1
assert_array_almost_equal(labels, [0, 0])
def test_int64_indices_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
n, labels = csgraph.connected_components(g, directed=True,
connection='strong')
assert n == 2
assert_array_almost_equal(labels, [1, 0])

61
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_conversions.py Normal file
View file

@ -0,0 +1,61 @@
import numpy as np
from numpy.testing import assert_array_almost_equal
from scipy.sparse import csr_array
from scipy.sparse.csgraph import csgraph_from_dense, csgraph_to_dense
def test_csgraph_from_dense():
np.random.seed(1234)
G = np.random.random((10, 10))
some_nulls = (G < 0.4)
all_nulls = (G < 0.8)
for null_value in [0, np.nan, np.inf]:
G[all_nulls] = null_value
with np.errstate(invalid="ignore"):
G_csr = csgraph_from_dense(G, null_value=0)
G[all_nulls] = 0
assert_array_almost_equal(G, G_csr.toarray())
for null_value in [np.nan, np.inf]:
G[all_nulls] = 0
G[some_nulls] = null_value
with np.errstate(invalid="ignore"):
G_csr = csgraph_from_dense(G, null_value=0)
G[all_nulls] = 0
assert_array_almost_equal(G, G_csr.toarray())
def test_csgraph_to_dense():
np.random.seed(1234)
G = np.random.random((10, 10))
nulls = (G < 0.8)
G[nulls] = np.inf
G_csr = csgraph_from_dense(G)
for null_value in [0, 10, -np.inf, np.inf]:
G[nulls] = null_value
assert_array_almost_equal(G, csgraph_to_dense(G_csr, null_value))
def test_multiple_edges():
# create a random square matrix with an even number of elements
np.random.seed(1234)
X = np.random.random((10, 10))
Xcsr = csr_array(X)
# now double-up every other column
Xcsr.indices[::2] = Xcsr.indices[1::2]
# normal sparse toarray() will sum the duplicated edges
Xdense = Xcsr.toarray()
assert_array_almost_equal(Xdense[:, 1::2],
X[:, ::2] + X[:, 1::2])
# csgraph_to_dense chooses the minimum of each duplicated edge
Xdense = csgraph_to_dense(Xcsr)
assert_array_almost_equal(Xdense[:, 1::2],
np.minimum(X[:, ::2], X[:, 1::2]))

209
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_flow.py Normal file
View file

@ -0,0 +1,209 @@
import numpy as np
from numpy.testing import assert_array_equal
import pytest
from scipy.sparse import csr_array, csc_array, csr_matrix
from scipy.sparse.csgraph import maximum_flow
from scipy.sparse.csgraph._flow import (
_add_reverse_edges, _make_edge_pointers, _make_tails
)
methods = ['edmonds_karp', 'dinic']
def test_raises_on_dense_input():
with pytest.raises(TypeError):
graph = np.array([[0, 1], [0, 0]])
maximum_flow(graph, 0, 1)
maximum_flow(graph, 0, 1, method='edmonds_karp')
def test_raises_on_csc_input():
with pytest.raises(TypeError):
graph = csc_array([[0, 1], [0, 0]])
maximum_flow(graph, 0, 1)
maximum_flow(graph, 0, 1, method='edmonds_karp')
def test_raises_on_floating_point_input():
with pytest.raises(ValueError):
graph = csr_array([[0, 1.5], [0, 0]], dtype=np.float64)
maximum_flow(graph, 0, 1)
maximum_flow(graph, 0, 1, method='edmonds_karp')
def test_raises_on_non_square_input():
with pytest.raises(ValueError):
graph = csr_array([[0, 1, 2], [2, 1, 0]])
maximum_flow(graph, 0, 1)
def test_raises_when_source_is_sink():
with pytest.raises(ValueError):
graph = csr_array([[0, 1], [0, 0]])
maximum_flow(graph, 0, 0)
maximum_flow(graph, 0, 0, method='edmonds_karp')
@pytest.mark.parametrize('method', methods)
@pytest.mark.parametrize('source', [-1, 2, 3])
def test_raises_when_source_is_out_of_bounds(source, method):
with pytest.raises(ValueError):
graph = csr_array([[0, 1], [0, 0]])
maximum_flow(graph, source, 1, method=method)
@pytest.mark.parametrize('method', methods)
@pytest.mark.parametrize('sink', [-1, 2, 3])
def test_raises_when_sink_is_out_of_bounds(sink, method):
with pytest.raises(ValueError):
graph = csr_array([[0, 1], [0, 0]])
maximum_flow(graph, 0, sink, method=method)
@pytest.mark.parametrize('method', methods)
def test_simple_graph(method):
# This graph looks as follows:
# (0) --5--> (1)
graph = csr_array([[0, 5], [0, 0]])
res = maximum_flow(graph, 0, 1, method=method)
assert res.flow_value == 5
expected_flow = np.array([[0, 5], [-5, 0]])
assert_array_equal(res.flow.toarray(), expected_flow)
@pytest.mark.parametrize('method', methods)
def test_return_type(method):
graph = csr_array([[0, 5], [0, 0]])
assert isinstance(maximum_flow(graph, 0, 1, method=method).flow, csr_array)
graph = csr_matrix([[0, 5], [0, 0]])
assert isinstance(maximum_flow(graph, 0, 1, method=method).flow, csr_matrix)
@pytest.mark.parametrize('method', methods)
def test_bottle_neck_graph(method):
# This graph cannot use the full capacity between 0 and 1:
# (0) --5--> (1) --3--> (2)
graph = csr_array([[0, 5, 0], [0, 0, 3], [0, 0, 0]])
res = maximum_flow(graph, 0, 2, method=method)
assert res.flow_value == 3
expected_flow = np.array([[0, 3, 0], [-3, 0, 3], [0, -3, 0]])
assert_array_equal(res.flow.toarray(), expected_flow)
@pytest.mark.parametrize('method', methods)
def test_backwards_flow(method):
# This example causes backwards flow between vertices 3 and 4,
# and so this test ensures that we handle that accordingly. See
# https://stackoverflow.com/q/38843963/5085211
# for more information.
graph = csr_array([[0, 10, 0, 0, 10, 0, 0, 0],
[0, 0, 10, 0, 0, 0, 0, 0],
[0, 0, 0, 10, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 10],
[0, 0, 0, 10, 0, 10, 0, 0],
[0, 0, 0, 0, 0, 0, 10, 0],
[0, 0, 0, 0, 0, 0, 0, 10],
[0, 0, 0, 0, 0, 0, 0, 0]])
res = maximum_flow(graph, 0, 7, method=method)
assert res.flow_value == 20
expected_flow = np.array([[0, 10, 0, 0, 10, 0, 0, 0],
[-10, 0, 10, 0, 0, 0, 0, 0],
[0, -10, 0, 10, 0, 0, 0, 0],
[0, 0, -10, 0, 0, 0, 0, 10],
[-10, 0, 0, 0, 0, 10, 0, 0],
[0, 0, 0, 0, -10, 0, 10, 0],
[0, 0, 0, 0, 0, -10, 0, 10],
[0, 0, 0, -10, 0, 0, -10, 0]])
assert_array_equal(res.flow.toarray(), expected_flow)
@pytest.mark.parametrize('method', methods)
def test_example_from_clrs_chapter_26_1(method):
# See page 659 in CLRS second edition, but note that the maximum flow
# we find is slightly different than the one in CLRS; we push a flow of
# 12 to v_1 instead of v_2.
graph = csr_array([[0, 16, 13, 0, 0, 0],
[0, 0, 10, 12, 0, 0],
[0, 4, 0, 0, 14, 0],
[0, 0, 9, 0, 0, 20],
[0, 0, 0, 7, 0, 4],
[0, 0, 0, 0, 0, 0]])
res = maximum_flow(graph, 0, 5, method=method)
assert res.flow_value == 23
expected_flow = np.array([[0, 12, 11, 0, 0, 0],
[-12, 0, 0, 12, 0, 0],
[-11, 0, 0, 0, 11, 0],
[0, -12, 0, 0, -7, 19],
[0, 0, -11, 7, 0, 4],
[0, 0, 0, -19, -4, 0]])
assert_array_equal(res.flow.toarray(), expected_flow)
@pytest.mark.parametrize('method', methods)
def test_disconnected_graph(method):
# This tests the following disconnected graph:
# (0) --5--> (1) (2) --3--> (3)
graph = csr_array([[0, 5, 0, 0],
[0, 0, 0, 0],
[0, 0, 9, 3],
[0, 0, 0, 0]])
res = maximum_flow(graph, 0, 3, method=method)
assert res.flow_value == 0
expected_flow = np.zeros((4, 4), dtype=np.int32)
assert_array_equal(res.flow.toarray(), expected_flow)
@pytest.mark.parametrize('method', methods)
def test_add_reverse_edges_large_graph(method):
# Regression test for https://github.com/scipy/scipy/issues/14385
n = 100_000
indices = np.arange(1, n)
indptr = np.array(list(range(n)) + [n - 1])
data = np.ones(n - 1, dtype=np.int32)
graph = csr_array((data, indices, indptr), shape=(n, n))
res = maximum_flow(graph, 0, n - 1, method=method)
assert res.flow_value == 1
expected_flow = graph - graph.transpose()
assert_array_equal(res.flow.data, expected_flow.data)
assert_array_equal(res.flow.indices, expected_flow.indices)
assert_array_equal(res.flow.indptr, expected_flow.indptr)
@pytest.mark.parametrize("a,b_data_expected", [
([[]], []),
([[0], [0]], []),
([[1, 0, 2], [0, 0, 0], [0, 3, 0]], [1, 2, 0, 0, 3]),
([[9, 8, 7], [4, 5, 6], [0, 0, 0]], [9, 8, 7, 4, 5, 6, 0, 0])])
def test_add_reverse_edges(a, b_data_expected):
"""Test that the reversal of the edges of the input graph works
as expected.
"""
a = csr_array(a, dtype=np.int32, shape=(len(a), len(a)))
b = _add_reverse_edges(a)
assert_array_equal(b.data, b_data_expected)
@pytest.mark.parametrize("a,expected", [
([[]], []),
([[0]], []),
([[1]], [0]),
([[0, 1], [10, 0]], [1, 0]),
([[1, 0, 2], [0, 0, 3], [4, 5, 0]], [0, 3, 4, 1, 2])
])
def test_make_edge_pointers(a, expected):
a = csr_array(a, dtype=np.int32)
rev_edge_ptr = _make_edge_pointers(a)
assert_array_equal(rev_edge_ptr, expected)
@pytest.mark.parametrize("a,expected", [
([[]], []),
([[0]], []),
([[1]], [0]),
([[0, 1], [10, 0]], [0, 1]),
([[1, 0, 2], [0, 0, 3], [4, 5, 0]], [0, 0, 1, 2, 2])
])
def test_make_tails(a, expected):
a = csr_array(a, dtype=np.int32)
tails = _make_tails(a)
assert_array_equal(tails, expected)

368
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_graph_laplacian.py Normal file
View file

@ -0,0 +1,368 @@
import pytest
import numpy as np
from numpy.testing import assert_allclose
from pytest import raises as assert_raises
from scipy import sparse
from scipy.sparse import csgraph
from scipy._lib._util import np_long, np_ulong
def check_int_type(mat):
return np.issubdtype(mat.dtype, np.signedinteger) or np.issubdtype(
mat.dtype, np_ulong
)
def test_laplacian_value_error():
for t in int, float, complex:
for m in ([1, 1],
[[[1]]],
[[1, 2, 3], [4, 5, 6]],
[[1, 2], [3, 4], [5, 5]]):
A = np.array(m, dtype=t)
assert_raises(ValueError, csgraph.laplacian, A)
def _explicit_laplacian(x, normed=False):
if sparse.issparse(x):
x = x.toarray()
x = np.asarray(x)
y = -1.0 * x
for j in range(y.shape[0]):
y[j,j] = x[j,j+1:].sum() + x[j,:j].sum()
if normed:
d = np.diag(y).copy()
d[d == 0] = 1.0
y /= d[:,None]**.5
y /= d[None,:]**.5
return y
def _check_symmetric_graph_laplacian(mat, normed, copy=True):
if not hasattr(mat, 'shape'):
mat = eval(mat, dict(np=np, sparse=sparse))
if sparse.issparse(mat):
sp_mat = mat
mat = sp_mat.toarray()
else:
sp_mat = sparse.csr_array(mat)
mat_copy = np.copy(mat)
sp_mat_copy = sparse.csr_array(sp_mat, copy=True)
n_nodes = mat.shape[0]
explicit_laplacian = _explicit_laplacian(mat, normed=normed)
laplacian = csgraph.laplacian(mat, normed=normed, copy=copy)
sp_laplacian = csgraph.laplacian(sp_mat, normed=normed,
copy=copy)
if copy:
assert_allclose(mat, mat_copy)
_assert_allclose_sparse(sp_mat, sp_mat_copy)
else:
if not (normed and check_int_type(mat)):
assert_allclose(laplacian, mat)
if sp_mat.format == 'coo':
_assert_allclose_sparse(sp_laplacian, sp_mat)
assert_allclose(laplacian, sp_laplacian.toarray())
for tested in [laplacian, sp_laplacian.toarray()]:
if not normed:
assert_allclose(tested.sum(axis=0), np.zeros(n_nodes))
assert_allclose(tested.T, tested)
assert_allclose(tested, explicit_laplacian)
def test_symmetric_graph_laplacian():
symmetric_mats = (
'np.arange(10) * np.arange(10)[:, np.newaxis]',
'np.ones((7, 7))',
'np.eye(19)',
'sparse.diags([1, 1], [-1, 1], shape=(4, 4))',
'sparse.diags([1, 1], [-1, 1], shape=(4, 4)).toarray()',
'sparse.diags([1, 1], [-1, 1], shape=(4, 4)).todense()',
'np.vander(np.arange(4)) + np.vander(np.arange(4)).T'
)
for mat in symmetric_mats:
for normed in True, False:
for copy in True, False:
_check_symmetric_graph_laplacian(mat, normed, copy)
def _assert_allclose_sparse(a, b, **kwargs):
# helper function that can deal with sparse matrices
if sparse.issparse(a):
a = a.toarray()
if sparse.issparse(b):
b = b.toarray()
assert_allclose(a, b, **kwargs)
def _check_laplacian_dtype_none(
A, desired_L, desired_d, normed, use_out_degree, copy, dtype, arr_type
):
mat = arr_type(A, dtype=dtype)
L, d = csgraph.laplacian(
mat,
normed=normed,
return_diag=True,
use_out_degree=use_out_degree,
copy=copy,
dtype=None,
)
if normed and check_int_type(mat):
assert L.dtype == np.float64
assert d.dtype == np.float64
_assert_allclose_sparse(L, desired_L, atol=1e-12)
_assert_allclose_sparse(d, desired_d, atol=1e-12)
else:
assert L.dtype == dtype
assert d.dtype == dtype
desired_L = np.asarray(desired_L).astype(dtype)
desired_d = np.asarray(desired_d).astype(dtype)
_assert_allclose_sparse(L, desired_L, atol=1e-12)
_assert_allclose_sparse(d, desired_d, atol=1e-12)
if not copy:
if not (normed and check_int_type(mat)):
if type(mat) is np.ndarray:
assert_allclose(L, mat)
elif mat.format == "coo":
_assert_allclose_sparse(L, mat)
def _check_laplacian_dtype(
A, desired_L, desired_d, normed, use_out_degree, copy, dtype, arr_type
):
mat = arr_type(A, dtype=dtype)
L, d = csgraph.laplacian(
mat,
normed=normed,
return_diag=True,
use_out_degree=use_out_degree,
copy=copy,
dtype=dtype,
)
assert L.dtype == dtype
assert d.dtype == dtype
desired_L = np.asarray(desired_L).astype(dtype)
desired_d = np.asarray(desired_d).astype(dtype)
_assert_allclose_sparse(L, desired_L, atol=1e-12)
_assert_allclose_sparse(d, desired_d, atol=1e-12)
if not copy:
if not (normed and check_int_type(mat)):
if type(mat) is np.ndarray:
assert_allclose(L, mat)
elif mat.format == 'coo':
_assert_allclose_sparse(L, mat)
INT_DTYPES = (np.intc, np_long, np.longlong)
REAL_DTYPES = (np.float32, np.float64, np.longdouble)
COMPLEX_DTYPES = (np.complex64, np.complex128, np.clongdouble)
DTYPES = INT_DTYPES + REAL_DTYPES + COMPLEX_DTYPES
@pytest.mark.parametrize("dtype", DTYPES)
@pytest.mark.parametrize("arr_type", [np.array,
sparse.csr_matrix,
sparse.coo_matrix,
sparse.csr_array,
sparse.coo_array])
@pytest.mark.parametrize("copy", [True, False])
@pytest.mark.parametrize("normed", [True, False])
@pytest.mark.parametrize("use_out_degree", [True, False])
def test_asymmetric_laplacian(use_out_degree, normed,
copy, dtype, arr_type):
# adjacency matrix
A = [[0, 1, 0],
[4, 2, 0],
[0, 0, 0]]
A = arr_type(np.array(A), dtype=dtype)
A_copy = A.copy()
if not normed and use_out_degree:
# Laplacian matrix using out-degree
L = [[1, -1, 0],
[-4, 4, 0],
[0, 0, 0]]
d = [1, 4, 0]
if normed and use_out_degree:
# normalized Laplacian matrix using out-degree
L = [[1, -0.5, 0],
[-2, 1, 0],
[0, 0, 0]]
d = [1, 2, 1]
if not normed and not use_out_degree:
# Laplacian matrix using in-degree
L = [[4, -1, 0],
[-4, 1, 0],
[0, 0, 0]]
d = [4, 1, 0]
if normed and not use_out_degree:
# normalized Laplacian matrix using in-degree
L = [[1, -0.5, 0],
[-2, 1, 0],
[0, 0, 0]]
d = [2, 1, 1]
_check_laplacian_dtype_none(
A,
L,
d,
normed=normed,
use_out_degree=use_out_degree,
copy=copy,
dtype=dtype,
arr_type=arr_type,
)
_check_laplacian_dtype(
A_copy,
L,
d,
normed=normed,
use_out_degree=use_out_degree,
copy=copy,
dtype=dtype,
arr_type=arr_type,
)
@pytest.mark.parametrize("fmt", ['csr', 'csc', 'coo', 'lil',
'dok', 'dia', 'bsr'])
@pytest.mark.parametrize("normed", [True, False])
@pytest.mark.parametrize("copy", [True, False])
def test_sparse_formats(fmt, normed, copy):
mat = sparse.diags_array([1, 1], offsets=[-1, 1], shape=(4, 4), format=fmt)
_check_symmetric_graph_laplacian(mat, normed, copy)
@pytest.mark.parametrize(
"arr_type", [np.asarray,
sparse.csr_matrix,
sparse.coo_matrix,
sparse.csr_array,
sparse.coo_array]
)
@pytest.mark.parametrize("form", ["array", "function", "lo"])
def test_laplacian_symmetrized(arr_type, form):
# adjacency matrix
n = 3
mat = arr_type(np.arange(n * n).reshape(n, n))
L_in, d_in = csgraph.laplacian(
mat,
return_diag=True,
form=form,
)
L_out, d_out = csgraph.laplacian(
mat,
return_diag=True,
use_out_degree=True,
form=form,
)
Ls, ds = csgraph.laplacian(
mat,
return_diag=True,
symmetrized=True,
form=form,
)
Ls_normed, ds_normed = csgraph.laplacian(
mat,
return_diag=True,
symmetrized=True,
normed=True,
form=form,
)
mat += mat.T
Lss, dss = csgraph.laplacian(mat, return_diag=True, form=form)
Lss_normed, dss_normed = csgraph.laplacian(
mat,
return_diag=True,
normed=True,
form=form,
)
assert_allclose(ds, d_in + d_out)
assert_allclose(ds, dss)
assert_allclose(ds_normed, dss_normed)
d = {}
for L in ["L_in", "L_out", "Ls", "Ls_normed", "Lss", "Lss_normed"]:
if form == "array":
d[L] = eval(L)
else:
d[L] = eval(L)(np.eye(n, dtype=mat.dtype))
_assert_allclose_sparse(d["Ls"], d["L_in"] + d["L_out"].T)
_assert_allclose_sparse(d["Ls"], d["Lss"])
_assert_allclose_sparse(d["Ls_normed"], d["Lss_normed"])
@pytest.mark.parametrize(
"arr_type", [np.asarray,
sparse.csr_matrix,
sparse.coo_matrix,
sparse.csr_array,
sparse.coo_array]
)
@pytest.mark.parametrize("dtype", DTYPES)
@pytest.mark.parametrize("normed", [True, False])
@pytest.mark.parametrize("symmetrized", [True, False])
@pytest.mark.parametrize("use_out_degree", [True, False])
@pytest.mark.parametrize("form", ["function", "lo"])
def test_format(dtype, arr_type, normed, symmetrized, use_out_degree, form):
n = 3
mat = [[0, 1, 0], [4, 2, 0], [0, 0, 0]]
mat = arr_type(np.array(mat), dtype=dtype)
Lo, do = csgraph.laplacian(
mat,
return_diag=True,
normed=normed,
symmetrized=symmetrized,
use_out_degree=use_out_degree,
dtype=dtype,
)
La, da = csgraph.laplacian(
mat,
return_diag=True,
normed=normed,
symmetrized=symmetrized,
use_out_degree=use_out_degree,
dtype=dtype,
form="array",
)
assert_allclose(do, da)
_assert_allclose_sparse(Lo, La)
L, d = csgraph.laplacian(
mat,
return_diag=True,
normed=normed,
symmetrized=symmetrized,
use_out_degree=use_out_degree,
dtype=dtype,
form=form,
)
assert_allclose(d, do)
assert d.dtype == dtype
Lm = L(np.eye(n, dtype=mat.dtype)).astype(dtype)
_assert_allclose_sparse(Lm, Lo, rtol=2e-7, atol=2e-7)
x = np.arange(6).reshape(3, 2)
if not (normed and dtype in INT_DTYPES):
assert_allclose(L(x), Lo @ x)
else:
# Normalized Lo is casted to integer, but L() is not
pass
def test_format_error_message():
with pytest.raises(ValueError, match="Invalid form: 'toto'"):
_ = csgraph.laplacian(np.eye(1), form='toto')

307
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_matching.py Normal file
View file

@ -0,0 +1,307 @@
from itertools import product
import numpy as np
from numpy.testing import assert_array_equal, assert_equal
import pytest
from scipy.sparse import csr_array, coo_array, diags_array
from scipy.sparse.csgraph import (
maximum_bipartite_matching, min_weight_full_bipartite_matching
)
def test_maximum_bipartite_matching_raises_on_dense_input():
with pytest.raises(TypeError):
graph = np.array([[0, 1], [0, 0]])
maximum_bipartite_matching(graph)
def test_maximum_bipartite_matching_empty_graph():
graph = csr_array((0, 0))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
expected_matching = np.array([])
assert_array_equal(expected_matching, x)
assert_array_equal(expected_matching, y)
def test_maximum_bipartite_matching_empty_left_partition():
graph = csr_array((2, 0))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
assert_array_equal(np.array([]), x)
assert_array_equal(np.array([-1, -1]), y)
def test_maximum_bipartite_matching_empty_right_partition():
graph = csr_array((0, 3))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
assert_array_equal(np.array([-1, -1, -1]), x)
assert_array_equal(np.array([]), y)
def test_maximum_bipartite_matching_graph_with_no_edges():
graph = csr_array((2, 2))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
assert_array_equal(np.array([-1, -1]), x)
assert_array_equal(np.array([-1, -1]), y)
def test_maximum_bipartite_matching_graph_that_causes_augmentation():
# In this graph, column 1 is initially assigned to row 1, but it should be
# reassigned to make room for row 2.
graph = csr_array([[1, 1], [1, 0]])
x = maximum_bipartite_matching(graph, perm_type='column')
y = maximum_bipartite_matching(graph, perm_type='row')
expected_matching = np.array([1, 0])
assert_array_equal(expected_matching, x)
assert_array_equal(expected_matching, y)
def test_maximum_bipartite_matching_graph_with_more_rows_than_columns():
graph = csr_array([[1, 1], [1, 0], [0, 1]])
x = maximum_bipartite_matching(graph, perm_type='column')
y = maximum_bipartite_matching(graph, perm_type='row')
assert_array_equal(np.array([0, -1, 1]), x)
assert_array_equal(np.array([0, 2]), y)
def test_maximum_bipartite_matching_graph_with_more_columns_than_rows():
graph = csr_array([[1, 1, 0], [0, 0, 1]])
x = maximum_bipartite_matching(graph, perm_type='column')
y = maximum_bipartite_matching(graph, perm_type='row')
assert_array_equal(np.array([0, 2]), x)
assert_array_equal(np.array([0, -1, 1]), y)
def test_maximum_bipartite_matching_explicit_zeros_count_as_edges():
data = [0, 0]
indices = [1, 0]
indptr = [0, 1, 2]
graph = csr_array((data, indices, indptr), shape=(2, 2))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
expected_matching = np.array([1, 0])
assert_array_equal(expected_matching, x)
assert_array_equal(expected_matching, y)
def test_maximum_bipartite_matching_feasibility_of_result():
# This is a regression test for GitHub issue #11458
data = np.ones(50, dtype=int)
indices = [11, 12, 19, 22, 23, 5, 22, 3, 8, 10, 5, 6, 11, 12, 13, 5, 13,
14, 20, 22, 3, 15, 3, 13, 14, 11, 12, 19, 22, 23, 5, 22, 3, 8,
10, 5, 6, 11, 12, 13, 5, 13, 14, 20, 22, 3, 15, 3, 13, 14]
indptr = [0, 5, 7, 10, 10, 15, 20, 22, 22, 23, 25, 30, 32, 35, 35, 40, 45,
47, 47, 48, 50]
graph = csr_array((data, indices, indptr), shape=(20, 25))
x = maximum_bipartite_matching(graph, perm_type='row')
y = maximum_bipartite_matching(graph, perm_type='column')
assert (x != -1).sum() == 13
assert (y != -1).sum() == 13
# Ensure that each element of the matching is in fact an edge in the graph.
for u, v in zip(range(graph.shape[0]), y):
if v != -1:
assert graph[u, v]
for u, v in zip(x, range(graph.shape[1])):
if u != -1:
assert graph[u, v]
def test_matching_large_random_graph_with_one_edge_incident_to_each_vertex():
np.random.seed(42)
A = diags_array(np.ones(25), offsets=0, format='csr')
rand_perm = np.random.permutation(25)
rand_perm2 = np.random.permutation(25)
Rrow = np.arange(25)
Rcol = rand_perm
Rdata = np.ones(25, dtype=int)
Rmat = csr_array((Rdata, (Rrow, Rcol)))
Crow = rand_perm2
Ccol = np.arange(25)
Cdata = np.ones(25, dtype=int)
Cmat = csr_array((Cdata, (Crow, Ccol)))
# Randomly permute identity matrix
B = Rmat @ A @ Cmat
# Row permute
perm = maximum_bipartite_matching(B, perm_type='row')
Rrow = np.arange(25)
Rcol = perm
Rdata = np.ones(25, dtype=int)
Rmat = csr_array((Rdata, (Rrow, Rcol)))
C1 = Rmat @ B
# Column permute
perm2 = maximum_bipartite_matching(B, perm_type='column')
Crow = perm2
Ccol = np.arange(25)
Cdata = np.ones(25, dtype=int)
Cmat = csr_array((Cdata, (Crow, Ccol)))
C2 = B @ Cmat
# Should get identity matrix back
assert_equal(any(C1.diagonal() == 0), False)
assert_equal(any(C2.diagonal() == 0), False)
@pytest.mark.parametrize('num_rows,num_cols', [(0, 0), (2, 0), (0, 3)])
def test_min_weight_full_matching_trivial_graph(num_rows, num_cols):
biadjacency = csr_array((num_cols, num_rows))
biadjacency1 = coo_array((num_cols, num_rows))
row_ind, col_ind = min_weight_full_bipartite_matching(biadjacency)
assert len(row_ind) == 0
assert len(col_ind) == 0
row_ind1, col_ind1 = min_weight_full_bipartite_matching(biadjacency1)
assert len(row_ind1) == 0
assert len(col_ind1) == 0
@pytest.mark.parametrize('biadjacency',
[
[[1, 1, 1], [1, 0, 0], [1, 0, 0]],
[[1, 1, 1], [0, 0, 1], [0, 0, 1]],
[[1, 0, 0, 1], [1, 1, 0, 1], [0, 0, 0, 0]],
[[1, 0, 0], [2, 0, 0]],
[[0, 1, 0], [0, 2, 0]],
[[1, 0], [2, 0], [5, 0]]
])
def test_min_weight_full_matching_infeasible_problems(biadjacency):
with pytest.raises(ValueError):
min_weight_full_bipartite_matching(csr_array(biadjacency))
with pytest.raises(ValueError):
min_weight_full_bipartite_matching(coo_array(biadjacency))
def test_min_weight_full_matching_large_infeasible():
# Regression test for GitHub issue #17269
a = np.asarray([
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001],
[0.0, 0.11687445, 0.0, 0.0, 0.01319788, 0.07509257, 0.0,
0.0, 0.0, 0.74228317, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.81087935, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.8408466, 0.0, 0.0, 0.0, 0.0, 0.01194389,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.82994211, 0.0, 0.0, 0.0, 0.11468516, 0.0, 0.0, 0.0,
0.11173505, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0],
[0.18796507, 0.0, 0.04002318, 0.0, 0.0, 0.0, 0.0, 0.0, 0.75883335,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.71545464, 0.0, 0.0, 0.0, 0.0, 0.0, 0.02748488,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.78470564, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.14829198,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.10870609, 0.0, 0.0, 0.0, 0.8918677, 0.0, 0.0, 0.0, 0.06306644,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
0.63844085, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.7442354, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.09850549, 0.0, 0.0, 0.18638258,
0.2769244, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.73182464, 0.0, 0.0, 0.46443561,
0.38589284, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
[0.29510278, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.09666032, 0.0,
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
])
with pytest.raises(ValueError, match='no full matching exists'):
min_weight_full_bipartite_matching(csr_array(a))
with pytest.raises(ValueError, match='no full matching exists'):
min_weight_full_bipartite_matching(coo_array(a))
@pytest.mark.thread_unsafe
def test_explicit_zero_causes_warning():
biadjacency = csr_array(((2, 0, 3), (0, 1, 1), (0, 2, 3)))
with pytest.warns(UserWarning):
min_weight_full_bipartite_matching(biadjacency)
with pytest.warns(UserWarning):
min_weight_full_bipartite_matching(biadjacency.tocoo())
# General test for linear sum assignment solvers to make it possible to rely
# on the same tests for scipy.optimize.linear_sum_assignment.
def linear_sum_assignment_assertions(
solver, array_type, sign, test_case
):
cost_matrix, expected_cost = test_case
maximize = sign == -1
cost_matrix = sign * array_type(cost_matrix)
expected_cost = sign * np.array(expected_cost)
row_ind, col_ind = solver(cost_matrix, maximize=maximize)
assert_array_equal(row_ind, np.sort(row_ind))
assert_array_equal(expected_cost,
np.array(cost_matrix[row_ind, col_ind]).flatten())
cost_matrix = cost_matrix.T
row_ind, col_ind = solver(cost_matrix, maximize=maximize)
assert_array_equal(row_ind, np.sort(row_ind))
assert_array_equal(np.sort(expected_cost),
np.sort(np.array(
cost_matrix[row_ind, col_ind])).flatten())
linear_sum_assignment_test_cases = product(
[-1, 1],
[
# Square
([[400, 150, 400],
[400, 450, 600],
[300, 225, 300]],
[150, 400, 300]),
# Rectangular variant
([[400, 150, 400, 1],
[400, 450, 600, 2],
[300, 225, 300, 3]],
[150, 2, 300]),
([[10, 10, 8],
[9, 8, 1],
[9, 7, 4]],
[10, 1, 7]),
# Square
([[10, 10, 8, 11],
[9, 8, 1, 1],
[9, 7, 4, 10]],
[10, 1, 4]),
# Rectangular variant
([[10, float("inf"), float("inf")],
[float("inf"), float("inf"), 1],
[float("inf"), 7, float("inf")]],
[10, 1, 7])
])
@pytest.mark.parametrize('sign,test_case', linear_sum_assignment_test_cases)
def test_min_weight_full_matching_small_inputs(sign, test_case):
linear_sum_assignment_assertions(
min_weight_full_bipartite_matching, csr_array, sign, test_case)

197
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_pydata_sparse.py Normal file
View file

@ -0,0 +1,197 @@
import pytest
import numpy as np
import scipy.sparse as sp
import scipy.sparse.csgraph as spgraph
from scipy._lib import _pep440
from numpy.testing import assert_equal
try:
import sparse
except Exception:
sparse = None
pytestmark = pytest.mark.skipif(sparse is None,
reason="pydata/sparse not installed")
msg = "pydata/sparse (0.15.1) does not implement necessary operations"
sparse_params = (pytest.param("COO"),
pytest.param("DOK", marks=[pytest.mark.xfail(reason=msg)]))
def check_sparse_version(min_ver):
if sparse is None:
return pytest.mark.skip(reason="sparse is not installed")
return pytest.mark.skipif(
_pep440.parse(sparse.__version__) < _pep440.Version(min_ver),
reason=f"sparse version >= {min_ver} required"
)
@pytest.fixture(params=sparse_params)
def sparse_cls(request):
return getattr(sparse, request.param)
@pytest.fixture
def graphs(sparse_cls):
graph = [
[0, 1, 1, 0, 0],
[0, 0, 1, 0, 0],
[0, 0, 0, 0, 0],
[0, 0, 0, 0, 1],
[0, 0, 0, 0, 0],
]
A_dense = np.array(graph)
A_sparse = sparse_cls(A_dense)
return A_dense, A_sparse
@pytest.mark.parametrize(
"func",
[
spgraph.shortest_path,
spgraph.dijkstra,
spgraph.floyd_warshall,
spgraph.bellman_ford,
spgraph.johnson,
spgraph.reverse_cuthill_mckee,
spgraph.maximum_bipartite_matching,
spgraph.structural_rank,
]
)
def test_csgraph_equiv(func, graphs):
A_dense, A_sparse = graphs
actual = func(A_sparse)
desired = func(sp.csc_array(A_dense))
assert_equal(actual, desired)
def test_connected_components(graphs):
A_dense, A_sparse = graphs
func = spgraph.connected_components
actual_comp, actual_labels = func(A_sparse)
desired_comp, desired_labels, = func(sp.csc_array(A_dense))
assert actual_comp == desired_comp
assert_equal(actual_labels, desired_labels)
def test_laplacian(graphs):
A_dense, A_sparse = graphs
sparse_cls = type(A_sparse)
func = spgraph.laplacian
actual = func(A_sparse)
desired = func(sp.csc_array(A_dense))
assert isinstance(actual, sparse_cls)
assert_equal(actual.todense(), desired.todense())
@pytest.mark.parametrize(
"func", [spgraph.breadth_first_order, spgraph.depth_first_order]
)
def test_order_search(graphs, func):
A_dense, A_sparse = graphs
actual = func(A_sparse, 0)
desired = func(sp.csc_array(A_dense), 0)
assert_equal(actual, desired)
@pytest.mark.parametrize(
"func", [spgraph.breadth_first_tree, spgraph.depth_first_tree]
)
def test_tree_search(graphs, func):
A_dense, A_sparse = graphs
sparse_cls = type(A_sparse)
actual = func(A_sparse, 0)
desired = func(sp.csc_array(A_dense), 0)
assert isinstance(actual, sparse_cls)
assert_equal(actual.todense(), desired.todense())
def test_minimum_spanning_tree(graphs):
A_dense, A_sparse = graphs
sparse_cls = type(A_sparse)
func = spgraph.minimum_spanning_tree
actual = func(A_sparse)
desired = func(sp.csc_array(A_dense))
assert isinstance(actual, sparse_cls)
assert_equal(actual.todense(), desired.todense())
def test_maximum_flow(graphs):
A_dense, A_sparse = graphs
sparse_cls = type(A_sparse)
func = spgraph.maximum_flow
actual = func(A_sparse, 0, 2)
desired = func(sp.csr_array(A_dense), 0, 2)
assert actual.flow_value == desired.flow_value
assert isinstance(actual.flow, sparse_cls)
assert_equal(actual.flow.todense(), desired.flow.todense())
def test_min_weight_full_bipartite_matching(graphs):
A_dense, A_sparse = graphs
func = spgraph.min_weight_full_bipartite_matching
actual = func(A_sparse[0:2, 1:3])
A_csc = sp.csc_array(A_dense)
desired = func(A_csc[0:2, 1:3])
desired1 = func(A_csc[0:2, 1:3].tocoo())
assert_equal(actual, desired)
assert_equal(actual, desired1)
@check_sparse_version("0.15.4")
@pytest.mark.parametrize(
"func",
[
spgraph.shortest_path,
spgraph.dijkstra,
spgraph.floyd_warshall,
spgraph.bellman_ford,
spgraph.johnson,
spgraph.minimum_spanning_tree,
]
)
@pytest.mark.parametrize(
"fill_value, comp_func",
[(np.inf, np.isposinf), (np.nan, np.isnan)],
)
def test_nonzero_fill_value(graphs, func, fill_value, comp_func):
A_dense, A_sparse = graphs
A_sparse = A_sparse.astype(float)
A_sparse.fill_value = fill_value
sparse_cls = type(A_sparse)
actual = func(A_sparse)
desired = func(sp.csc_array(A_dense))
if func == spgraph.minimum_spanning_tree:
assert isinstance(actual, sparse_cls)
assert comp_func(actual.fill_value)
actual = actual.todense()
actual[comp_func(actual)] = 0.0
assert_equal(actual, desired.todense())
else:
assert_equal(actual, desired)

70
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_reordering.py Normal file
View file

@ -0,0 +1,70 @@
import numpy as np
from numpy.testing import assert_equal
from scipy.sparse.csgraph import reverse_cuthill_mckee, structural_rank
from scipy.sparse import csc_array, csr_array, coo_array
def test_graph_reverse_cuthill_mckee():
A = np.array([[1, 0, 0, 0, 1, 0, 0, 0],
[0, 1, 1, 0, 0, 1, 0, 1],
[0, 1, 1, 0, 1, 0, 0, 0],
[0, 0, 0, 1, 0, 0, 1, 0],
[1, 0, 1, 0, 1, 0, 0, 0],
[0, 1, 0, 0, 0, 1, 0, 1],
[0, 0, 0, 1, 0, 0, 1, 0],
[0, 1, 0, 0, 0, 1, 0, 1]], dtype=int)
graph = csr_array(A)
perm = reverse_cuthill_mckee(graph)
correct_perm = np.array([6, 3, 7, 5, 1, 2, 4, 0])
assert_equal(perm, correct_perm)
# Test int64 indices input
graph.indices = graph.indices.astype('int64')
graph.indptr = graph.indptr.astype('int64')
perm = reverse_cuthill_mckee(graph, True)
assert_equal(perm, correct_perm)
def test_graph_reverse_cuthill_mckee_ordering():
data = np.ones(63,dtype=int)
rows = np.array([0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2,
2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5,
6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9,
9, 10, 10, 10, 10, 10, 11, 11, 11, 11,
12, 12, 12, 13, 13, 13, 13, 14, 14, 14,
14, 15, 15, 15, 15, 15])
cols = np.array([0, 2, 5, 8, 10, 1, 3, 9, 11, 0, 2,
7, 10, 1, 3, 11, 4, 6, 12, 14, 0, 7, 13,
15, 4, 6, 14, 2, 5, 7, 15, 0, 8, 10, 13,
1, 9, 11, 0, 2, 8, 10, 15, 1, 3, 9, 11,
4, 12, 14, 5, 8, 13, 15, 4, 6, 12, 14,
5, 7, 10, 13, 15])
graph = csr_array((data, (rows,cols)))
perm = reverse_cuthill_mckee(graph)
correct_perm = np.array([12, 14, 4, 6, 10, 8, 2, 15,
0, 13, 7, 5, 9, 11, 1, 3])
assert_equal(perm, correct_perm)
def test_graph_structural_rank():
# Test square matrix #1
A = csc_array([[1, 1, 0],
[1, 0, 1],
[0, 1, 0]])
assert_equal(structural_rank(A), 3)
# Test square matrix #2
rows = np.array([0,0,0,0,0,1,1,2,2,3,3,3,3,3,3,4,4,5,5,6,6,7,7])
cols = np.array([0,1,2,3,4,2,5,2,6,0,1,3,5,6,7,4,5,5,6,2,6,2,4])
data = np.ones_like(rows)
B = coo_array((data,(rows,cols)), shape=(8,8))
assert_equal(structural_rank(B), 6)
#Test non-square matrix
C = csc_array([[1, 0, 2, 0],
[2, 0, 4, 0]])
assert_equal(structural_rank(C), 2)
#Test tall matrix
assert_equal(structural_rank(C.T), 2)

540
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_shortest_path.py Normal file
View file

@ -0,0 +1,540 @@
from io import StringIO
import warnings
import numpy as np
from numpy.testing import assert_array_almost_equal, assert_array_equal, assert_allclose
from pytest import raises as assert_raises
from scipy.sparse.csgraph import (shortest_path, dijkstra, johnson,
bellman_ford, construct_dist_matrix, yen,
NegativeCycleError)
import scipy.sparse
from scipy.io import mmread
import pytest
directed_G = np.array([[0, 3, 3, 0, 0],
[0, 0, 0, 2, 4],
[0, 0, 0, 0, 0],
[1, 0, 0, 0, 0],
[2, 0, 0, 2, 0]], dtype=float)
# Undirected version of directed_G
undirected_G = np.array([[0, 3, 3, 1, 2],
[3, 0, 0, 2, 4],
[3, 0, 0, 0, 0],
[1, 2, 0, 0, 2],
[2, 4, 0, 2, 0]], dtype=float)
unweighted_G = (directed_G > 0).astype(float)
# Correct shortest path lengths for directed_G and undirected_G
directed_SP = [[0, 3, 3, 5, 7],
[3, 0, 6, 2, 4],
[np.inf, np.inf, 0, np.inf, np.inf],
[1, 4, 4, 0, 8],
[2, 5, 5, 2, 0]]
directed_2SP_0_to_3 = [[-9999, 0, -9999, 1, -9999],
[-9999, 0, -9999, 4, 1]]
undirected_SP = np.array([[0, 3, 3, 1, 2],
[3, 0, 6, 2, 4],
[3, 6, 0, 4, 5],
[1, 2, 4, 0, 2],
[2, 4, 5, 2, 0]], dtype=float)
undirected_SP_limit_2 = np.array([[0, np.inf, np.inf, 1, 2],
[np.inf, 0, np.inf, 2, np.inf],
[np.inf, np.inf, 0, np.inf, np.inf],
[1, 2, np.inf, 0, 2],
[2, np.inf, np.inf, 2, 0]], dtype=float)
undirected_SP_limit_0 = np.ones((5, 5), dtype=float) - np.eye(5)
undirected_SP_limit_0[undirected_SP_limit_0 > 0] = np.inf
# Correct predecessors for directed_G and undirected_G
directed_pred = np.array([[-9999, 0, 0, 1, 1],
[3, -9999, 0, 1, 1],
[-9999, -9999, -9999, -9999, -9999],
[3, 0, 0, -9999, 1],
[4, 0, 0, 4, -9999]], dtype=float)
undirected_pred = np.array([[-9999, 0, 0, 0, 0],
[1, -9999, 0, 1, 1],
[2, 0, -9999, 0, 0],
[3, 3, 0, -9999, 3],
[4, 4, 0, 4, -9999]], dtype=float)
# Other graphs
directed_sparse_zero_G = scipy.sparse.csr_array(
(
[0, 1, 2, 3, 1],
([0, 1, 2, 3, 4], [1, 2, 0, 4, 3]),
),
shape=(5, 5),
)
directed_sparse_zero_SP = [[0, 0, 1, np.inf, np.inf],
[3, 0, 1, np.inf, np.inf],
[2, 2, 0, np.inf, np.inf],
[np.inf, np.inf, np.inf, 0, 3],
[np.inf, np.inf, np.inf, 1, 0]]
undirected_sparse_zero_G = scipy.sparse.csr_array(
(
[0, 0, 1, 1, 2, 2, 1, 1],
([0, 1, 1, 2, 2, 0, 3, 4], [1, 0, 2, 1, 0, 2, 4, 3])
),
shape=(5, 5),
)
undirected_sparse_zero_SP = [[0, 0, 1, np.inf, np.inf],
[0, 0, 1, np.inf, np.inf],
[1, 1, 0, np.inf, np.inf],
[np.inf, np.inf, np.inf, 0, 1],
[np.inf, np.inf, np.inf, 1, 0]]
directed_negative_weighted_G = np.array([[0, 0, 0],
[-1, 0, 0],
[0, -1, 0]], dtype=float)
directed_negative_weighted_SP = np.array([[0, np.inf, np.inf],
[-1, 0, np.inf],
[-2, -1, 0]], dtype=float)
methods = ['auto', 'FW', 'D', 'BF', 'J']
def test_dijkstra_limit():
limits = [0, 2, np.inf]
results = [undirected_SP_limit_0,
undirected_SP_limit_2,
undirected_SP]
def check(limit, result):
SP = dijkstra(undirected_G, directed=False, limit=limit)
assert_array_almost_equal(SP, result)
for limit, result in zip(limits, results):
check(limit, result)
def test_directed():
def check(method):
SP = shortest_path(directed_G, method=method, directed=True,
overwrite=False)
assert_array_almost_equal(SP, directed_SP)
for method in methods:
check(method)
def test_undirected():
def check(method, directed_in):
if directed_in:
SP1 = shortest_path(directed_G, method=method, directed=False,
overwrite=False)
assert_array_almost_equal(SP1, undirected_SP)
else:
SP2 = shortest_path(undirected_G, method=method, directed=True,
overwrite=False)
assert_array_almost_equal(SP2, undirected_SP)
for method in methods:
for directed_in in (True, False):
check(method, directed_in)
def test_directed_sparse_zero():
# test directed sparse graph with zero-weight edge and two connected components
def check(method):
SP = shortest_path(directed_sparse_zero_G, method=method, directed=True,
overwrite=False)
assert_array_almost_equal(SP, directed_sparse_zero_SP)
for method in methods:
check(method)
def test_undirected_sparse_zero():
def check(method, directed_in):
if directed_in:
SP1 = shortest_path(directed_sparse_zero_G, method=method, directed=False,
overwrite=False)
assert_array_almost_equal(SP1, undirected_sparse_zero_SP)
else:
SP2 = shortest_path(undirected_sparse_zero_G, method=method, directed=True,
overwrite=False)
assert_array_almost_equal(SP2, undirected_sparse_zero_SP)
for method in methods:
for directed_in in (True, False):
check(method, directed_in)
@pytest.mark.parametrize('directed, SP_ans',
((True, directed_SP),
(False, undirected_SP)))
@pytest.mark.parametrize('indices', ([0, 2, 4], [0, 4], [3, 4], [0, 0]))
def test_dijkstra_indices_min_only(directed, SP_ans, indices):
SP_ans = np.array(SP_ans)
indices = np.array(indices, dtype=np.int64)
min_ind_ans = indices[np.argmin(SP_ans[indices, :], axis=0)]
min_d_ans = np.zeros(SP_ans.shape[0], SP_ans.dtype)
for k in range(SP_ans.shape[0]):
min_d_ans[k] = SP_ans[min_ind_ans[k], k]
min_ind_ans[np.isinf(min_d_ans)] = -9999
SP, pred, sources = dijkstra(directed_G,
directed=directed,
indices=indices,
min_only=True,
return_predecessors=True)
assert_array_almost_equal(SP, min_d_ans)
assert_array_equal(min_ind_ans, sources)
SP = dijkstra(directed_G,
directed=directed,
indices=indices,
min_only=True,
return_predecessors=False)
assert_array_almost_equal(SP, min_d_ans)
@pytest.mark.parametrize('n', (10, 100, 1000))
def test_dijkstra_min_only_random(n):
rng = np.random.default_rng(7345782358920239234)
data = scipy.sparse.random_array((n, n), density=0.5, format='lil',
rng=rng, dtype=np.float64)
data.setdiag(np.zeros(n, dtype=np.bool_))
# choose some random vertices
v = np.arange(n)
rng.shuffle(v)
indices = v[:int(n*.1)]
ds, pred, sources = dijkstra(data,
directed=True,
indices=indices,
min_only=True,
return_predecessors=True)
for k in range(n):
p = pred[k]
s = sources[k]
while p != -9999:
assert sources[p] == s
p = pred[p]
@pytest.mark.parametrize('n', (10, 100))
@pytest.mark.parametrize("method", ['FW', 'J', 'BF'])
@pytest.mark.parametrize('directed', (True, False))
def test_star_graph(n, method, directed):
# Build the star graph
star_arr = np.zeros((n, n), dtype=float)
star_center_idx = 0
star_arr[star_center_idx, :] = star_arr[:, star_center_idx] = range(n)
G = scipy.sparse.csr_matrix(star_arr, shape=(n, n))
# Build the distances matrix
SP_solution = np.zeros((n, n), dtype=float)
SP_solution[:] = star_arr[star_center_idx]
for idx in range(1, n):
SP_solution[idx] += star_arr[idx, star_center_idx]
np.fill_diagonal(SP_solution, 0)
SP = shortest_path(G, method=method, directed=directed)
assert_allclose(
SP_solution, SP
)
def test_dijkstra_random():
# reproduces the hang observed in gh-17782
n = 10
indices = [0, 4, 4, 5, 7, 9, 0, 6, 2, 3, 7, 9, 1, 2, 9, 2, 5, 6]
indptr = [0, 0, 2, 5, 6, 7, 8, 12, 15, 18, 18]
data = [0.33629, 0.40458, 0.47493, 0.42757, 0.11497, 0.91653, 0.69084,
0.64979, 0.62555, 0.743, 0.01724, 0.99945, 0.31095, 0.15557,
0.02439, 0.65814, 0.23478, 0.24072]
graph = scipy.sparse.csr_array((data, indices, indptr), shape=(n, n))
dijkstra(graph, directed=True, return_predecessors=True)
def test_gh_17782_segfault():
text = """%%MatrixMarket matrix coordinate real general
84 84 22
2 1 4.699999809265137e+00
6 14 1.199999973177910e-01
9 6 1.199999973177910e-01
10 16 2.012000083923340e+01
11 10 1.422000026702881e+01
12 1 9.645999908447266e+01
13 18 2.012000083923340e+01
14 13 4.679999828338623e+00
15 11 1.199999973177910e-01
16 12 1.199999973177910e-01
18 15 1.199999973177910e-01
32 2 2.299999952316284e+00
33 20 6.000000000000000e+00
33 32 5.000000000000000e+00
36 9 3.720000028610229e+00
36 37 3.720000028610229e+00
36 38 3.720000028610229e+00
37 44 8.159999847412109e+00
38 32 7.903999328613281e+01
43 20 2.400000000000000e+01
43 33 4.000000000000000e+00
44 43 6.028000259399414e+01
"""
data = mmread(StringIO(text), spmatrix=False)
dijkstra(data, directed=True, return_predecessors=True)
def test_shortest_path_indices():
indices = np.arange(4)
def check(func, indshape):
outshape = indshape + (5,)
SP = func(directed_G, directed=False,
indices=indices.reshape(indshape))
assert_array_almost_equal(SP, undirected_SP[indices].reshape(outshape))
for indshape in [(4,), (4, 1), (2, 2)]:
for func in (dijkstra, bellman_ford, johnson, shortest_path):
check(func, indshape)
assert_raises(ValueError, shortest_path, directed_G, method='FW',
indices=indices)
def test_predecessors():
SP_res = {True: directed_SP,
False: undirected_SP}
pred_res = {True: directed_pred,
False: undirected_pred}
def check(method, directed):
SP, pred = shortest_path(directed_G, method, directed=directed,
overwrite=False,
return_predecessors=True)
assert_array_almost_equal(SP, SP_res[directed])
assert_array_almost_equal(pred, pred_res[directed])
for method in methods:
for directed in (True, False):
check(method, directed)
def test_construct_shortest_path():
def check(method, directed):
SP1, pred = shortest_path(directed_G,
directed=directed,
overwrite=False,
return_predecessors=True)
SP2 = construct_dist_matrix(directed_G, pred, directed=directed)
assert_array_almost_equal(SP1, SP2)
for method in methods:
for directed in (True, False):
check(method, directed)
@pytest.mark.parametrize("directed", [True, False])
def test_construct_dist_matrix_predecessors_error(directed):
SP1, pred = shortest_path(directed_G,
directed=directed,
overwrite=False,
return_predecessors=True)
assert_raises(TypeError, construct_dist_matrix,
directed_G, pred.astype(np.int64), directed)
def test_unweighted_path():
def check(method, directed):
SP1 = shortest_path(directed_G,
directed=directed,
overwrite=False,
unweighted=True)
SP2 = shortest_path(unweighted_G,
directed=directed,
overwrite=False,
unweighted=False)
assert_array_almost_equal(SP1, SP2)
for method in methods:
for directed in (True, False):
check(method, directed)
def test_negative_cycles():
# create a small graph with a negative cycle
graph = np.ones([5, 5])
graph.flat[::6] = 0
graph[1, 2] = -2
def check(method, directed):
assert_raises(NegativeCycleError, shortest_path, graph, method,
directed)
for directed in (True, False):
for method in ['FW', 'J', 'BF']:
check(method, directed)
assert_raises(NegativeCycleError, yen, graph, 0, 1, 1,
directed=directed)
@pytest.mark.parametrize("method", ['FW', 'J', 'BF'])
def test_negative_weights(method):
SP = shortest_path(directed_negative_weighted_G, method, directed=True)
assert_allclose(SP, directed_negative_weighted_SP, atol=1e-10)
def test_masked_input():
np.ma.masked_equal(directed_G, 0)
def check(method):
SP = shortest_path(directed_G, method=method, directed=True,
overwrite=False)
assert_array_almost_equal(SP, directed_SP)
for method in methods:
check(method)
def test_overwrite():
G = np.array([[0, 3, 3, 1, 2],
[3, 0, 0, 2, 4],
[3, 0, 0, 0, 0],
[1, 2, 0, 0, 2],
[2, 4, 0, 2, 0]], dtype=float)
foo = G.copy()
shortest_path(foo, overwrite=False)
assert_array_equal(foo, G)
@pytest.mark.parametrize('method', methods)
def test_buffer(method):
# Smoke test that sparse matrices with read-only buffers (e.g., those from
# joblib workers) do not cause::
#
# ValueError: buffer source array is read-only
#
G = scipy.sparse.csr_array([[1.]])
G.data.flags['WRITEABLE'] = False
shortest_path(G, method=method)
def test_NaN_warnings():
with warnings.catch_warnings(record=True) as record:
shortest_path(np.array([[0, 1], [np.nan, 0]]))
for r in record:
assert r.category is not RuntimeWarning
def test_sparse_matrices():
# Test that using lil,csr and csc sparse matrix do not cause error
G_dense = np.array([[0, 3, 0, 0, 0],
[0, 0, -1, 0, 0],
[0, 0, 0, 2, 0],
[0, 0, 0, 0, 4],
[0, 0, 0, 0, 0]], dtype=float)
SP = shortest_path(G_dense)
G_csr = scipy.sparse.csr_array(G_dense)
G_csc = scipy.sparse.csc_array(G_dense)
G_lil = scipy.sparse.lil_array(G_dense)
assert_array_almost_equal(SP, shortest_path(G_csr))
assert_array_almost_equal(SP, shortest_path(G_csc))
assert_array_almost_equal(SP, shortest_path(G_lil))
def test_yen_directed():
distances, predecessors = yen(
directed_G,
source=0,
sink=3,
K=2,
return_predecessors=True
)
assert_allclose(distances, [5., 9.])
assert_allclose(predecessors, directed_2SP_0_to_3)
def test_yen_dense():
dense_undirected_G = np.array([
[0, 3, 3, 1, 2],
[3, 0, 7, 6, 5],
[3, 7, 0, 4, 0],
[1, 6, 4, 0, 2],
[2, 5, 0, 2, 0]], dtype=float)
distances = yen(
dense_undirected_G,
source=0,
sink=4,
K=5,
directed=False,
)
assert_allclose(distances, [2., 3., 8., 9., 11.])
def test_yen_undirected():
distances = yen(
undirected_G,
source=0,
sink=3,
K=4,
directed=False,
)
assert_allclose(distances, [1., 4., 5., 8.])
def test_yen_unweighted():
# Ask for more paths than there are, verify only the available paths are returned
distances, predecessors = yen(
directed_G,
source=0,
sink=3,
K=4,
unweighted=True,
return_predecessors=True,
)
assert_allclose(distances, [2., 3.])
assert_allclose(predecessors, directed_2SP_0_to_3)
def test_yen_no_paths():
distances = yen(
directed_G,
source=2,
sink=3,
K=1,
)
assert distances.size == 0
def test_yen_negative_weights():
distances = yen(
directed_negative_weighted_G,
source=2,
sink=0,
K=1,
)
assert_allclose(distances, [-2.])
@pytest.mark.parametrize("min_only", (True, False))
@pytest.mark.parametrize("directed", (True, False))
@pytest.mark.parametrize("return_predecessors", (True, False))
@pytest.mark.parametrize("index_dtype", (np.int32, np.int64))
@pytest.mark.parametrize("indices", (None, [1]))
def test_20904(min_only, directed, return_predecessors, index_dtype, indices):
"""Test two failures from gh-20904: int32 and indices-as-None."""
adj_mat = scipy.sparse.eye_array(4, format="csr")
adj_mat = scipy.sparse.csr_array(
(
adj_mat.data,
adj_mat.indices.astype(index_dtype),
adj_mat.indptr.astype(index_dtype),
),
)
dijkstra(
adj_mat,
directed,
indices=indices,
min_only=min_only,
return_predecessors=return_predecessors,
)

66
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_spanning_tree.py Normal file
View file

@ -0,0 +1,66 @@
"""Test the minimum spanning tree function"""
import numpy as np
from numpy.testing import assert_
import numpy.testing as npt
from scipy.sparse import csr_array
from scipy.sparse.csgraph import minimum_spanning_tree
def test_minimum_spanning_tree():
# Create a graph with two connected components.
graph = [[0,1,0,0,0],
[1,0,0,0,0],
[0,0,0,8,5],
[0,0,8,0,1],
[0,0,5,1,0]]
graph = np.asarray(graph)
# Create the expected spanning tree.
expected = [[0,1,0,0,0],
[0,0,0,0,0],
[0,0,0,0,5],
[0,0,0,0,1],
[0,0,0,0,0]]
expected = np.asarray(expected)
# Ensure minimum spanning tree code gives this expected output.
csgraph = csr_array(graph)
mintree = minimum_spanning_tree(csgraph)
mintree_array = mintree.toarray()
npt.assert_array_equal(mintree_array, expected,
'Incorrect spanning tree found.')
# Ensure that the original graph was not modified.
npt.assert_array_equal(csgraph.toarray(), graph,
'Original graph was modified.')
# Now let the algorithm modify the csgraph in place.
mintree = minimum_spanning_tree(csgraph, overwrite=True)
npt.assert_array_equal(mintree.toarray(), expected,
'Graph was not properly modified to contain MST.')
np.random.seed(1234)
for N in (5, 10, 15, 20):
# Create a random graph.
graph = 3 + np.random.random((N, N))
csgraph = csr_array(graph)
# The spanning tree has at most N - 1 edges.
mintree = minimum_spanning_tree(csgraph)
assert_(mintree.nnz < N)
# Set the sub diagonal to 1 to create a known spanning tree.
idx = np.arange(N-1)
graph[idx,idx+1] = 1
csgraph = csr_array(graph)
mintree = minimum_spanning_tree(csgraph)
# We expect to see this pattern in the spanning tree and otherwise
# have this zero.
expected = np.zeros((N, N))
expected[idx, idx+1] = 1
npt.assert_array_equal(mintree.toarray(), expected,
'Incorrect spanning tree found.')

148
venv/lib/python3.13/site-packages/scipy/sparse/csgraph/tests/test_traversal.py Normal file
View file

@ -0,0 +1,148 @@
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]])