[R] Instructions for upgrading R on ubuntu

[Andrew Crane-Droesch]

I am trying to upgrade to R 3.0.1, and I am working on ubuntu. 
Apparently, the new version is available in the following ppa: 
https://launchpad.net/~marutter/+archive/c2d4u.  I have added this ppa 
to my software sources.

I then run the typical sudo apt-get update && sudo apt-get dist-upgrade, 
and R fails to upgrade from 2.15.2 to 3.0.1.  I then manually try to 
sudo apt-get install r-base-dev, which does not recognize that a new 
version is available from the newly-installed ppa.

I have tried using the GUI Software Center as well -- it lists R as 
installed, and makes no mention of the new version.

Could someone be so kind as to post step-by-step instructions for 
actually installing R 3.0.1?  Given issues with graphics in R2.15.2 with 
Ubuntu 13.04, I am sure that this will be useful to people besides me.

Thanks,
Andrew