R Beginners Course 2026

Session 3 :: Data I/O and Reshaping — Quiz

Dr. Debasish Mukherjee, Dr. Ulrike Goebel, Dr. Ali Abdallah

Bioinformatics Core Facility CECAD

2026-05-13

Session 3 :: Quiz

Test your understanding of base-R I/O, reshaping, and combining tables.

How to play

  • Each question may have one or more correct answers — select all that apply.
  • Click Check to score; Reset to try again.
  • Use the Tip button if you get stuck.
  • Discuss with your neighbour first!

Quiz

Take-home messages

Three things to remember:

  1. I/O — match the reader to the file. Text formats (CSV/TSV) for sharing; binary formats (RDS/RData) for saving R objects.
  2. Reshaping — know which shape your analysis needs. Wide ↔︎ long; use explicit idvar when you need to pivot back safely.
  3. Combining — dimensions vs. keys. cbind()/rbind() align by position; merge() aligns by key — and duplicated keys give a Cartesian product.