Problem with overlay(x="SpatialGridDataFrame", y="SpatialPoints")
On Tue, 31 Mar 2009, Rainer M Krug wrote:
On Tue, Mar 31, 2009 at 2:16 PM, Roger Bivand <Roger.Bivand at nhh.no> wrote:
On Tue, 31 Mar 2009, Rainer M Krug wrote: Hi
I want to get the data from a grid at locations based in a point vector file. I am using the following code, and I get the error below.
Rainer: The quick workaround is to read the shapefile with readOGR(), which does not give the coordinates matrix row names, so the failing test for matching with
Yes - it works with readOGR, which I like. But the problem is, that most attendants of the course use Windows (unfortunately), and as faer as I know is rgdal on windows tricky.
For what definition of tricky? The CRAN Windows binary ships with its own GDAL binaries and support files (thanks to Uwe Ligges), so I don't think it is harder to install than maptools (but is a much larger download for obvious reasons - it includes quite a lot of raster and vector drivers, and the GDAL and PROJ.4 support metadata files).
data frame row names is skipped. I have fixed overlay() to suit in sp's CVS on R-spatial on sourceforge - could you try it, please? The following will show if it
OK - it's working now. ANy idea when this will be available on CRAN?
sp_0.9-34.tar.gz submitted to CRAN, so probably tomorrow for the Windows build if it passes checks. Roger
Thanks a lot, Rainer is fixed:
library(sp)
data(meuse)
coordinates(meuse) <- c("x", "y")
data(meuse.grid)
coordinates(meuse.grid) <- c("x", "y")
gridded(meuse.grid) <- TRUE
fullgrid(meuse.grid) <- TRUE
zz <- overlay(meuse.grid, meuse)
library(rgdal)
writeOGR(meuse, "/tmp", "meuse", driver="ESRI Shapefile")
meuse <- readOGR("/tmp", "meuse")
zz <- overlay(meuse.grid, meuse)
library(maptools)
meuse <- readShapePoints("/tmp/meuse.shp")
zz <- overlay(meuse.grid, meuse)
Hope this helps,
Roger
Could anybody help to solve this?
Thanks
Rainer
lastFire <- readAsciiGrid("fire_last_2006.asc")
biota <- readShapePoints("Biota")
overlay(lastFire, biota)
Error in SpatialPointsDataFrame(cc, x at data[idx, , drop = FALSE], proj4string = CRS(proj4string(x))) : row.names of data and coords do not match
-- 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
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