R is a “a free software environment for statistical computing and graphics“. Being a desktop software, R is working out-of-the-box, even if you don’t have a network connection. However, if you want to install packages using a repository on the internet, you need a network connection (of course). If your computer happens to be behind a proxy server, you have to slightly modify your shortcut (in MS-Windows) to allow R to download packages. This can be done by modifying the “Target” field in the “Shortcut” tab of the shortcut properties (right-click on the shortcut to R, select tab “Shortcut”, edit field “Target”):
"C:\Program Files\R\R-2.12.2\bin\i386\Rgui.exe" http_proxy=http://proxyaddress:80 http_proxy_user=ask
Adapt the path to your R version, change the string “
proxyaddress” by your proxy (see this previous post for a tip on this) and you’re done!
Because I never remember them, I’ll conclude this post with standard commands related to the installation of a packages:
Installing packages in R:
> install.packages("packageName", repos = "http://cran.ma.imperial.ac.uk/", dependencies = TRUE)
- You might get a window asking you for your firewall credentials and to choose a mirror server
- CRAN repositories can be found here: http://cran.r-project.org/
- This will download and install the package again, even if it is already installed
Updating packages in R:
> update.packages("deSolve") # for the deSolve package, for example
Know all packages installed in R on your computer:
Finally, here is a R reference card that can be useful too.