scikit-learn/scikit-learn — pull request #3994 by jnothman (2014-12-23 12:04:49+00:00)
Title: [MRG] ENH vectorize DBSCAN implementation

This reduces the cluster comparison toy examples under DBSCAN from ~.6s each to .02s each on my machine.

(This could be sped up further by allowing a dual-tree radius_neighbors lookup that reuses the computed tree. The toy examples have `n_features=2`, so neighbor calculation does not take up as much of the overall time as it might otherwise.)