[Numpy-discussion] finding close together points.
Tue Nov 10 19:22:52 CST 2009
Also, is it not returning distances between points and themselves? Or am I
On Tue, Nov 10, 2009 at 5:17 PM, Christopher Barker
> James Bergstra wrote:
> > In some cases a brute-force approach is also good.
> > If r is a matrix of shape Nx2:
> > (r*r).sum(axis=1) -2 * numpy.dot(r, r.T) +
> > (r*r).sum(axis=1).reshape((r.shape, 1)) < thresh**2
> > It's brute force, but it takes advantage of fast matrix multiplication.
> I'm more concerned about memory -- doesn't this use N^2 memory? Which
> could be an issue here.
> Christopher Barker, Ph.D.
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