Michael,
I figured out the issue with unionSpatialPolygons() (I posted this on
R-sig-Geo as well):
Turns out that that I didn't have package "gpclib" installed. Once
installed, I could run the gpclibPermit() function, which set
gpclibPermitStatus() = T:
> library(maptools)
Loading required package: foreign
Loading required package: sp
Loading required package: lattice
Note: polygon geometry computations in maptools
depend on the package gpclib, which has a
restricted licence. It is disabled by default;
to enable gpclib, type gpclibPermit()
Checking rgeos availability as gpclib substitute:
FALSE
> gpclibPermit() # downloaded package "gpclib" to run this function
General Polygon Clipper Library for R (version 1.5-1)
Type 'class ? gpc.poly' for help
[1] TRUE
Then unionSpatialPolygons() works fine. As for the issue with
installing package "rgeos", I'm not sure of the issue, but I posted on
r-sig-geo the error, so hopefully they are aware of it now.
Ken
On 06/06/2010 07:55 PM, Michael Rutter wrote:
On 06/05/2010 07:28 PM, Kenneth Takagi wrote:
Hi,
I've cross posted with r-sig-debian since they may be an issue for linux
(never had this problem on my windows machine...)
I recently made the switch to Ubuntu 10.04 (lucid), and found that
unionSpatialPolygons() gives me the following error when trying to
combine polygons within a shapefile:
# Read in shapefile and merge polygons
foo <- readShapePoly("foo.shp", proj4string = CRS("+init=epsg:2272"))
IDs <- as.character(foo$ID)
SP_out <- unionSpatialPolygons(foo, IDs)
Error: isTRUE(gpclibPermitStatus()) is not TRUE
I've seen some posts about a package "rgeos" which may have something to
do with this error, and I downloaded the source from:
http://r-forge.r-project.org/R/?group_id=602
But when I've tried to install by source using R CMD INSTALL (or using
install.packages()) I get the following error message:
...lines of output not shown...
rgeos_misc.c: In function ?rgeos_hausdorffdistance?:
rgeos_misc.c:62: error: ?GEOSHausdorffDistance_r? undeclared (first use
in this function)
rgeos_misc.c:62: error: (Each undeclared identifier is reported only once
rgeos_misc.c:62: error: for each function it appears in.)
make: *** [rgeos_misc.o] Error 1
ERROR: compilation failed for package ?rgeos?
I'm using R version 2.11.1 (2010-05-31), in ubuntu 10.04 LTS
Thanks for any help you can offer on getting unionSpatialPolygon up and
running!
Ken
Ken,
Without a "foo.shp" file to use as an example, I can't recreate your
original R error. Can you redo the example given on page 57 of the
maptools pdf manual?
However, I can recreate the error when trying to install rgeos. That
error needs to be addressed with the rgeos developers, as it appears
that is an error in their code, not something that is missing in R or in
Ubuntu.
Hope this helps,
Michael
_______________________________________________
R-SIG-Debian mailing list
[email protected]
https://stat.ethz.ch/mailman/listinfo/r-sig-debian
