[R-sig-Geo] RE: A package for spatial data classes: request for comments

Nicholas Lewin-Koh nikko at hailmail.net
Tue Nov 4 15:43:39 CET 2003

I couldn't agree more with Barry Rowlingson. The initial set of basic
interfaces should be set up first then start building in the methods.
Without the underlying data structures well defined 
this could turn into a nightmare.

regarding topology, I am not sure that that is the most efficient set of
information necessary for
statistical computation. I think some sort of spatial indexing for fast
neighborhood calculation and spatial joins is important. I could see
topology being important for network modeling, where flow through the
network would be important, however that could be tackled again with
efficient contiguity calculations and a method to convert a map to a
graph data structure. A quad tree (or octtree for 3d data) or perhaps an
R-tree structure would be most effective. I was thinking about the
implementation this morning, and I thought this might be a good use of
the external pointer mechanism, with the option to write the data
structure as an R object to save and restore on startup (home grown

my 2c


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