[r] Where does R store packages?

The install.packages() function in R is the automatic unzipping utility that gets and install packages in R.

1. How do I find out what directory R has chosen to store packages?

2. How can I change the directory in which R stores and accesses packages?

Thanks for the direction from the above two answerers. James Thompson's suggestion worked best for Windows users.

1. Go to where your R program is installed. This is referred to as R_Home in the literature. Once you find it, go to the /etc subdirectory.

   C:\R\R-2.10.1\etc
   

2. Select the file in this folder named Rprofile.site. I open it with VIM. You will find this is a bare-bones file with less than 20 lines of code. I inserted the following inside the code:

   # my custom library path
   .libPaths("C:/R/library")
   

   (The comment added to keep track of what I did to the file.)

3. In R, typing the .libPaths() function yields the first target at C:/R/Library

NOTE: there is likely more than one way to achieve this, but other methods I tried didn't work for some reason.

This is documented in the 'R Installation and Administration' manual that came with your installation.

On my Linux box:

R> .libPaths()
[1] "/usr/local/lib/R/site-library" "/usr/lib/R/site-library"      
[3] "/usr/lib/R/library"           
R> 

meaning that the default path is the first of these. You can override that via an argument to both install.packages() (from inside R) or R CMD INSTALL (outside R).

You can also override by setting the R_LIBS_USER variable.

You do not want the '='

Use .libPaths("C:/R/library") in you Rprofile.site file

And make sure you have correct " symbol (Shift-2)