Specifying 'cosine' as metric in KDTree throws error #25364
Description
Describe the bug
I am trying to implement the KDTree Algorithm with cosine as a distance metric. I first started with scipy's implementation, but it didn't support cosine as a metric. Then, I came across sklearn implementation. The documentation indicates that the supported metric can be found (scipy.spatial.distance) and (distance_metrics). Both of these places show that the cosine metric is supported. Also, the user guide also suggests that cosine is supported as it tries to point out cosine as cosine_distance. However, it still throws an error for me when I try to use that metric.
Steps/Code to Reproduce
import numpy as np
from sklearn.neighbors import KDTree
rng = np.random.RandomState(0)
X = rng.random_sample((10, 3)) # 10 points in 3 dimensions
tree = KDTree(X, leaf_size=2, metric= "cosine") Expected Results
No error is thrown
Actual Results
Traceback (most recent call last):
File "sklearn/metrics/_dist_metrics.pyx", line 270, in sklearn.metrics._dist_metrics.DistanceMetric.get_metric
KeyError: 'cosine'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "sklearn/neighbors/_binary_tree.pxi", line 844, in sklearn.neighbors._kd_tree.BinaryTree.__init__
File "sklearn/metrics/_dist_metrics.pyx", line 272, in sklearn.metrics._dist_metrics.DistanceMetric.get_metric
ValueError: Unrecognized metric 'cosine'
Versions
System:
python: 3.8.10 (default, Mar 15 2022, 12:22:08) [GCC 9.4.0]
executable: /bin/python3
machine: Linux-5.4.0-132-generic-x86_64-with-glibc2.29
Python dependencies:
sklearn: 1.2.0
pip: 22.3.1
setuptools: 65.6.3
numpy: 1.23.3
scipy: 1.9.3
Cython: 0.29.30
pandas: 1.4.2
matplotlib: 3.6.2
joblib: 1.2.0
threadpoolctl: 3.1.0
Built with OpenMP: True
threadpoolctl info:
user_api: blas
internal_api: openblas
prefix: libopenblas
filepath: /usr/local/lib/python3.8/dist-packages/numpy.libs/libopenblas64_p-r0-742d56dc.3.20.so
version: 0.3.20
threading_layer: pthreads
architecture: SkylakeX
num_threads: 28
user_api: openmp
internal_api: openmp
prefix: libgomp
filepath: /usr/local/lib/python3.8/dist-packages/scikit_learn.libs/libgomp-a34b3233.so.1.0.0
version: None
num_threads: 28
user_api: blas
internal_api: openblas
prefix: libopenblas
filepath: /usr/local/lib/python3.8/dist-packages/scipy.libs/libopenblasp-r0-41284840.3.18.so
version: 0.3.18
threading_layer: pthreads
architecture: SkylakeX
num_threads: 28
user_api: openmp
internal_api: openmp
prefix: libgomp
filepath: /usr/local/lib/python3.8/dist-packages/torch/lib/libgomp-a34b3233.so.1
version: None
num_threads: 14