how to find cells in a raster

Roman,

Perhaps you can make a RasterLayer with the cell numbers and then use
xyValues with a buffer

r <- raster(original.raser)
r[] <- 1:ncell(r)
xyValues(r, points, buffer=?)

Robert
Dear list,

I'm trying to find cells in a RasterLayer object. Specifically, I'm trying
to find all cells within a radius from a pre-defined point. When I have cell
numbers or coordinates, I can calculate their distance from the
aforementioned pre-defined point.
So far, I've been overlaying a polygon and extracting cell numbers with
polygonValues(), however, this method seems to be somewhat slow (especially
on larger rasters). I've benchmarked it and it is approximately as fast as
if I used distanceFromPoints(), which calculates distances for all cells in
a raster. Is there a faster way of finding these cells?

Cheers,
Roman

--
In God we trust, all others bring data.

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how to find cells in a raster

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