Files
MLPproject/.venv/lib/python3.12/site-packages/skimage/metrics/_contingency_table.py
2025-10-23 15:44:32 +02:00

52 lines
1.7 KiB
Python

import scipy.sparse as sparse
import numpy as np
__all__ = ['contingency_table']
def contingency_table(
im_true, im_test, *, ignore_labels=None, normalize=False, sparse_type="matrix"
):
"""
Return the contingency table for all regions in matched segmentations.
Parameters
----------
im_true : ndarray of int
Ground-truth label image, same shape as im_test.
im_test : ndarray of int
Test image.
ignore_labels : sequence of int, optional
Labels to ignore. Any part of the true image labeled with any of these
values will not be counted in the score.
normalize : bool
Determines if the contingency table is normalized by pixel count.
sparse_type : {"matrix", "array"}, optional
The return type of `cont`, either `scipy.sparse.csr_array` or
`scipy.sparse.csr_matrix` (default).
Returns
-------
cont : scipy.sparse.csr_matrix or scipy.sparse.csr_array
A contingency table. `cont[i, j]` will equal the number of voxels
labeled `i` in `im_true` and `j` in `im_test`. Depending on `sparse_type`,
this can be returned as a `scipy.sparse.csr_array`.
"""
if ignore_labels is None:
ignore_labels = []
im_test_r = im_test.reshape(-1)
im_true_r = im_true.reshape(-1)
data = np.isin(im_true_r, ignore_labels, invert=True).astype(float)
if normalize:
data /= np.count_nonzero(data)
cont = sparse.csr_array((data, (im_true_r, im_test_r)))
if sparse_type == "matrix":
cont = sparse.csr_matrix(cont)
elif sparse_type != "array":
msg = f"`sparse_type` must be 'array' or 'matrix', got {sparse_type}"
raise ValueError(msg)
return cont