Intro to R Crash Course, Part 2

Friday, October 2 — continuation, incl. loops & apply functions

Friday, Oct 2, 12:10–1:00 PM, Asmundson 242. Continuation of Part 1 (Sep 25) — picks up where we left off, ending with loops vs. apply functions. Optional, but open to everyone.


Before you arrive

If you haven’t already, install R and RStudio — see the Setup guide.

The script we’ll work through in class

Same script as Part 1 — we continue from wherever we stopped on Sep 25. Follow along on your own laptop.

What’s in it:

  • Objects and 1D types in R (numeric, character, logical)
  • Beyond numeric: factors, dates, and other types
  • Vectors: creating, indexing, and vectorized operations
  • Beyond 1D: lists and data frames
  • Files, directories, and reading in data (read.csv)
  • Basic plotting with ggplot2
  • The pipe operator |>
  • Beginner+ skills: writing your own functions, and for loops vs. apply-family functions — the focus for this session

Data

The script reads in this dataset partway through — download it and keep it in your working directory:

Extra resources

Optional — if you’re new to R, or want more practice than we have time for in class.

Cheat sheets (quick reference, print or keep open in a tab):

  • Posit cheat sheets — RStudio IDE, data visualization (ggplot2), data transformation (dplyr/tidyr), and more, all one page each.

Guided tutorials / practice:

Free online book:

  • R for Data Science (2e) — the standard reference for the tidyverse approach to importing, wrangling, and visualizing data in R. More than you need for this course, but a good thing to have on hand.

Video:

  • StatQuest with Josh Starmer — short, clear explainer videos on R and statistics topics. A good channel to bookmark for later in the course too, now that the statistics fundamentals (Mon 9/28, Wed 9/30) are underway.