R & RStudio

R vs. RStudio

  • R is the programming language and runtime (it executes code).
  • RStudio (Posit IDE) is the graphical environment where you write code, manage files, and render documents.

You’ll always use them together: R runs under the hood; RStudio makes it easier to work productively.

The RStudio interface (four panes)

  1. Source (top-left): edit scripts and .qmd files
  2. Console (bottom-left): run code interactively
  3. Environment / History (top-right): see objects in memory, command history
  4. Files / Plots / Packages / Help / Viewer (bottom-right): navigate files, view plots, load packages, get help

Projects: your #1 best practice

Always work inside an RStudio Project (one folder per course or research project).

  • Each Project has its own working directory, history, and settings.
  • This avoids broken file paths and makes your work reproducible.

Create a Project:
File → New Project → New Directory → New Project

Pro tip: In Preferences → General, set RStudio to never save/restore .RData. Clean sessions prevent stale objects from carrying over.

Console vs. Script (and Quarto)

  • Use the Console for quick experiments.
  • Save work you want to keep in a script (.R) or a Quarto document (.qmd).

Render .qmd with the Render button (RStudio toolbar) or in a terminal:

quarto render myfile.qmd

Handy keys (Source pane)

  • Run line/selection: Ctrl+Enter (Win/Linux) or Cmd+Return (macOS)
  • Insert code chunk in .qmd: Ctrl+Alt+I (Win/Linux) or Option+Cmd+I (macOS)
  • Full list: Tools → Keyboard Shortcuts Help

Files and paths (keep them relative)

Inside a Project, paths are relative to the project root.

Example:

# Good (portable)
songs <- read.csv("data/songs.csv")

# Bad (breaks on other computers)
songs <- read.csv("C:/Users/Alex/Desktop/songs.csv")

Avoid setwd() in scripts. The Project sets the working directory automatically.

Git integration

If your Project is under Git, you’ll see a Git tab in RStudio. Use it to:

  • Stage → Commit → Push changes to GitHub.

If the Git tab is missing: Tools → Project Options → Git/SVN → Enable version control system: Git or run:

usethis::use_git()

Handy shortcuts

  • Command Palette: Ctrl/Cmd+Shift+P
  • Keyboard Shortcuts Help: Alt/Option+Shift+K
  • Comment/Uncomment: Ctrl+Shift+C (Win/Linux) or Cmd+Shift+C (macOS)

Default settings to adopt (once)

  • Disable save/restore of .RData (Preferences → General).
  • Keep Projects in simple paths (e.g., Documents/MC451).
  • Enable Git integration early.

Where this fits with the package

Everything in mccoursepack—listing weeks, downloading scaffolds, rendering .qmd—assumes you are inside your course Project.

Workflow reminder:

library(mccoursepack)

# list weeks
list_weeks("mc451")

# download week 1 into the project folder
download_week("mc451", 1, dest = ".")

Open the downloaded week_01/ folder, work on .qmd files there, and render as needed.