Applying the DRY principle to repetitive R code (CC132)

July 29, 2021 • PD Schloss • 1 min read • •

Do you have R scripts where you repeat the same chunk of code over and over? You need to learn about the DRY principle! DRY stands for Don’t Repeat Yourself. Following this principle will make your code easier to manage and help you to avoid propogating errors across your project. Check out this episode to see how Pat uses the DRY principle to minimize duplication and then demonstrates how to expand his code using the DRY principle.

In this episode, Pat will use functions from the mikropml R package and data handling functions from dplyr in RStudio.

Code

You can browse the state of the repository at the

• beginning of the episode
• end of the episode

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 958530ddf30b7e86f3aa38ac53f0010c344b7fae
    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.