[R] Installing package rgdal

[Alex Olssen]

Dear R-helpers,

I am trying to install the package "rgdal" using the command

install.packages("rgdal")

in R.  I get the following error

"Error: proj_api.h not found.
If the PROJ.4 library is installed in a non-standard location,
use --configure-args='--with-proj-include=/opt/local/include'
for example, replacing /opt/local/* with appropriate values
for your installation. If PROJ.4 is not installed, install it.
ERROR: configuration failed for package ‘rgdal’
* removing ‘/home/alex/R/i686-pc-linux-gnu-library/2.11/rgdal’

The downloaded packages are in
	‘/tmp/RtmpVDlld6/downloaded_packages’
Warning message:
In install.packages("rgdal") :
  installation of package 'rgdal' had non-zero exit status"

I am using ubuntu 10.10 and have installed PROJ.4 using the software
center.  I have also downloaded a binary of PROJ.4 and placed it in
/opt/local/

I have looked at the documentation for "rgdal" here -
http://cran.r-project.org/web/packages/rgdal/index.html
But it seems to be about using "rgdal" as opposed to installing it.

Any help would be appreciated.

Kind regards,

Alex