Nearest neighbor in python

[maxnoe]

For example, I once needed code to do fast calculation of nearest-neighbors of a given data point

First google hit for "nearest neighbor" is scikit-learns k nearest neighbor classifier, which links to the BallTree and KDTree classes it uses for neighbor finding:

• https://scikit-learn.org/stable/modules/neighbors.html
• https://scikit-learn.org/stable/modules/generated/sklearn.neighbors.BallTree.html#sklearn.neighbors.BallTree
• https://scikit-learn.org/stable/modules/generated/sklearn.neighbors.KDTree.html#sklearn.neighbors.KDTree

Little more googling about those algorithms gives you:

• https://docs.scipy.org/doc/scipy/reference/generated/scipy.spatial.cKDTree.html

Also, researching nearest neighbors in generall, will give you the answer, that a KDTree is one of the most efficient algorithms to do this and googling
kdtree python will yield the scipy implementation as first hit.

[matloff]

I did make a point of saying I wasn't interested in the classification app. Thanks for the tip on kdtree. Doesn't surprise me but it didn't come up in my PyPI search, which was my pt.

[maxnoe]

I did make a point of saying I wasn't interested in the classification app.

Yes, but the classification app uses and directly links to what you were looking for.