On Wed, 28 Apr 2010, Paul Hiemstra wrote:
Tim Erbrecht wrote:
Dear all,
having data in a SpatialGridDataFrame with geographic coordinates, is there
a simple method to calculate the spatial area for each cell? I wasn't able
to find anything in the list archives ...
Thanks and best regards
Tim
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with the meuse dataset:
library(sp)
data(meuse.grid)
gridded(meuse.grid) = ~x+y
fullgrid(meuse.grid) = TRUE
bla = gridparameters(meuse.grid)
area = bla$cellsize[1] * bla$cellsize[2]
area
These are projected, not geographical coordinates, unfortunately. The case
for calculating areas on an ellipsoid is much harder, I'm afraid.
Roger
cheers,
Paul
--
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: roger.biv...@nhh.no
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