problem with spTransform and SpatialPixelsDataFrame
On Wed, 20 Oct 2010, Julian Burgos wrote:
Dear list, I have a problem trying to change the projection of a SpatialPixelsDataFrame, from UTM to lat/long. My object has the following characteristics:
summary(mb)
Object of class SpatialPixelsDataFrame
Coordinates:
min max
X -14.17196 -13.76879
Y 63.75071 63.96791
Is projected: TRUE
proj4string : [+proj=utm +zone=28 +datum=WGS84]
Number of points: 5669540
Grid attributes:
cellcentre.offset cellsize cells.dim
X -14.17189 1.347473e-04 2992
Y 63.75074 5.944386e-05 3654
Data attributes:
Min. 1st Qu. Median Mean 3rd Qu. Max.
108.5 230.3 256.9 283.0 287.9 987.6
when using the spTransform I get the following error message:
mb=spTransform(mb,CRS("proj=longlat +datum=WGS84"))
Error in spTransform(mb, CRS("proj=longlat +datum=WGS84")) :
error in evaluating the argument 'CRSobj' in selecting a method for
function 'spTransform'
The error was caused by a missing +:
library(rgdal)
data(meuse.grid)
gridded(meuse.grid) <- TRUE
proj4string(meuse.grid) <- CRS("+init=epsg:28992")
ll <- spTransform(meuse.grid, CRS("proj=longlat +datum=WGS84"))
ll <- spTransform(meuse.grid, CRS("+proj=longlat +datum=WGS84"))
which coerces to points first, as Mike said it should.
Roger
Any ideas what is the problem? Many thanks, Julian Burgos Julian Mariano Burgos Hafranns?knastofnunin/Marine Research Institute Sk?lagata 4, 121 Reykjav?k, Iceland S?mi/Telephone : +354-5752037 Br?fs?mi/Telefax: +354-5752001 Netfang/Email: julian at hafro.is, jmburgos at uw.edu [[alternative HTML version deleted]]
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.Bivand at nhh.no