4.3 Reproducibility

Prioritizing reproducibility when writing code code not only fosters collaboration with others during a project, but also makes it easier for users in the future (including yourself!) to make changes and rerun analyses as new data become available. Some useful tools and practices include:

• Commenting code: Adding brief but detailed comments to your scripts that document what your code does and how it works will help others understand and use your scripts. At the top of your scripts, describe the purpose of the code as well as its necessary inputs, required packages, and outputs.
  
• File paths: Avoid writing file paths that only work on your computer. Where possible, use relative file paths instead of absolute files paths so your code can be run by different users or operating systems. For R users, using R Projects and/or the here package are great ways to help implement this practice.
• Functions: If you find yourself copying and pasting similar blocks of code over and over to repeat tasks, turn it into a function!
• R Markdown: R users can take advantage of R Markdown for a coding format that seamlessly integrates sections of text alongside code chunks. R Markdown also enables you to transform your code and text into report-friendly formats such as PDFs or Word documents.
• Git and GitHub: As described above, Git tracks changes to files line-by-line in commits that are attributable to each team member working on the project. GitHub then compiles the history of any Git-tracked file online, and synchronizes the work of all collaborators in a central repository. Using Git and GitHub allow multiple people to code collaboratively, examine changes as they occur, and restore prior versions of files if necessary.