How to upgrade R in linux?

Note: I now keep on GitHub (here) an up-to-date guide to upgrading R on Linux Mint or Ubuntu Linux, which also includes a bit of extra information about system dependencies for tidyverse, the popular set of data-wrangling packages, as well as devtools, the popular R package development... package.

The link provided by FedRo is a good resource, however a slight change would need to be made since you're using Linux Mint 18.1 which uses Xenial repositories rather than Trusty repositories (see here). I also typically use the approach here to deal with packages I've already installed when I upgrade R rather than the approach offered by FedRo. So, for completeness, these are all the steps you'd need to take:

Step 1

Go to CRAN's list of mirrors and find the URL of the mirror that is closest to you. The terminal commands below assume you choose http://cran.wustl.edu/

Step 2

Open a terminal and enter the following commands¹ (replacing http://cran.wustl.edu/ with whichever CRAN mirror URL you chose in step 1):

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys E298A3A825C0D65DFD57CBB651716619E084DAB9sudo echo "deb http://cran.wustl.edu/bin/linux/ubuntu xenial/" | sudo tee -a /etc/apt/sources.listsudo apt updatesudo apt upgrade r-base r-base-devsudo apt updatesudo apt upgrade

Note also that I have put to upgrade r-base and r-base-dev, but I don't know if you have r-base-dev installed. If not, I highly recommend you install it via sudo apt install r-base-dev.

Step 3

Start a new R session and run the following:

update.packages(checkBuilt=TRUE, ask=FALSE)

Then you should be good to go.

Update: Linux Mint 19 and R 3.6.x

Since both Linux Mint and R have seen upgrades since I answered this question, I'm updating for those who come to this answer needing the info for Linux Mint 19 and R 3.6.x.

The only difference is that instead of the command

sudo echo "deb http://cran.wustl.edu/bin/linux/ubuntu xenial/" | sudo tee -a /etc/apt/sources.list

you need to use

sudo echo "deb http://cran.wustl.edu/bin/linux/ubuntu bionic-cran35/" | sudo tee -a /etc/apt/sources.list

(replacing http://cran.wustl.edu/ with whichever CRAN mirror URL you chose in step 1)

¹ I put here the full key, though many other guides you may see will use only the "short key."I have updated this guide to use the full key out of security concerns (see here, for example).

Now it is very simple. Just make:

install.packages("ropenblas")ropenblas::rcompiler()