[R-sig-Geo] extracting non-NA values from RasterLayer

[Rafael Wüest]

Hi Carson,

check ?rasterToPoints from raster package. That should do it!

Rafi

On 25.04.2012, at 12:26, Carson Farmer wrote:

> Dear list, I am currently dealing with extremely large raster datasets
> (100s of millions of cells), and am masking out large regions which
> are of no particular interest for our current project. This produces
> RasterLayers with a large number of NAs (but still millions of non-NA
> cells as well). What I'd like to do is extract all non-NA values into
> a vector for use in various statistical analyses, but I am having
> trouble finding the most efficient means of doing so. Any pointers? I
> have tried "sampleRandom", which is supposed to only take non-NA
> cells, but there must be a better/faster way to extract *all* non-NA
> values that I've just missed.
> 
> Cheers,
> 
> Carson
> 
> -- 
> Dr. Carson J. Q. Farmer
> Centre for GeoInformatics (CGI)
> School of Geography and Geosciences
> Irvine Building, University of St Andrews
> St Andrews, Fife, KY16 9AL
> Scotland, UK
> 
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> R-sig-Geo at r-project.org
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Rafael Wüest
Swiss Federal Research Institute WSL
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