[R-sig-Geo] Spatial analysis - matrix algebra

[Dylan Beaudette]

On Mon, Jul 7, 2008 at 2:48 AM, Paulo Cardoso <pecardoso at netcabo.pt> wrote:
> Can R perform matrix algebra between ascii converted Esri grids? I'm
> convinced that its trivial.
>
>
>
> The question is a little more complex (from my point of view and
> inexperience): I'm interested in perform cost surface and distance surface
> analysis avoiding ArcGIS tools. Maybe R can deal with grid formatted as
> matrices...
>

Paulo,

GRASS would be my first choice for any type of raster operation. See
r.cost, r.drain, and r.walk for some examples of cost surface
modeling. Here is a worked example:

http://casoilresource.lawr.ucdavis.edu/drupal/node/544

Cheers,

Dylan