[Numpy-discussion] finding close together points.

[Christopher Barker]

Lou Pecora wrote:
> Maybe I'm missing something simple, but if your array of 2D points is
> static,

well, not quite.

> a KD tree for 2D nearest neighbor seems like over kill.  You
> might want to try the simple approach of using boxes of points to
> narrow things down by sorting on the first component.

yeah, we'll probably do something like that if we have to write the code 
ourselves. At the moment, we're using geohash:

http://pypi.python.org/pypi/Geohash/

(this is for points on the earth)

and it's working OK. I was just hoping kdtree would work out of the box!

 > where for a
> static data set it can match KD trees in speed

Why does it have to be static -- it doesn't look hard to insert/remove 
points.

-Chris





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