Using ggplot2 to group x-axis discrete values into subgroups (CC133)

August 2, 2021 • PD Schloss • 1 min read • •

When we group sets of variables into subgroups on the x-axis we signal to our audience that they need to compare the values within the grouping. But how do we do this with ggplot2? In this episode of Code Club, Pat will show how you can great four (!) layers of subgroups by using the ggplot2 facet_wrap function. At the end, we’ll revisit our code and see how we can make it more DRY.

Pat will use functions from the mikropml R package and the facet_wrap function from ggplot2 as well as functions from dplyr and purrr in RStudio.

Code

You can browse the state of the repository at the

Installations

If you haven’t been following along, you can get caught up by doing the following:

(windows) Install the Ubuntu Linux BASH shell for Windows 10

(mac) Install homebrew and git

  /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
  brew install git

To get to where we are at the beginning of this episode (you won’t have the same issue numbers at Pat)…
- Set up a GitHub account
- Create a new GitHub repository
  - Call it “mikropml_demo”
  - Make it Public
  - Don’t check the box next to “Initialize this repository with a README”
  - Click the green “Create repository” button
- Go to your command line and enter the following replacing <your_github_id> with your GitHub user id
```
git clone git@github.com:SchlossLab/mikropml_demo.git
cd mikropml_demo
git reset --hard 617a21c15924de143c3d5c71ef90d3b25aa92f80
git remote set-url origin git@github.com:<your_github_id>/mikropml_demo.git
git push -u origin master
```
- Return to GitHub and refresh your browser.
- Go to the mikropml_demo directory on your computer and double click on the mikropml_demo.Rproj icon. This will launch RStudio and you’ll be good to go.