[R-sig-Geo] Neighbor matrix from shp file

[Barry Rowlingson]

On Tue, May 11, 2010 at 9:40 PM, Roger Bivand <Roger.Bivand at nhh.no> wrote:
> On Tue, 11 May 2010, Barry Rowlingson wrote:

> Use the snap= argument to poly2nb() set to a larger but still small value
> than default in that case, say 10m for projected coordinates.

 Ooh, yes, that's fixed it.

> Barry, if you'd like to try SVN spdep from R-forge (and maybe also SVN rgeos
> from R-forge), you'll find a number of speedups. Any feedback on those would
> be very welcome.

 Computing the adjacency for about 1500 polygons with 127,000
coordinate points takes about 11 seconds - I should only need to do
this once so I don't think I'll investigate speedups at the moment!

thanks!

Barry

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