R Update

In Terminal: sudo gedit /etc/apt/sources.list The file will be opened in gedit. Append to file in the end: ## For installing and updating R deb http://cran.gis-lab.info/bin/linux/ubuntu trusty/

Save the file and close gedit. In Terminal write: sudo apt-get update

That will give you an error like: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 51716619E084DAB9 (The key number 51716619E084DAB9 can differ!)

Then you write in Terminal: sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 51716619E084DAB9 (key number is to be replaced with yours key number in error)

Then write in Terminal: sudo apt-get update and finally it should perform normally.

Then: sudo apt-get install r-base r-base-dev

Now you have the up-to-date R version!