Week 7: tidyr

DATA 412/612 · October 14

Lectures

• 7.1 tidyr: Tidy Data and pivot_longer()(PDF)
• 7.2 tidyr: pivot_wider(), separate(), unite()(PDF)
• tidyr cheat sheet (Posit)

Labs

• Lab 7: Tidying Data(PDF)
• Lab 7 solutions (password)

Additional readings

• R for Data Science: Tidy data
• tidyr: Pivoting
• What They Forgot to Teach You About R: Safe paths
• A tidyverse pivot approach to data preparation

Discussion

• Is a table tidy if each country is one row and 2020, 2021, and 2022 are column names? Why or why not?
• When would pivot_wider() after a summary help, and when would it make the next ggplot harder?