Multi-column keys
Two new datasets are available in your R session:
subjects: contains the subject each student is taking each semester this yearlocations: contains the room allocations for each subject
Your goal is to build a new data.table with the locations of each subject for each student.
Deze oefening maakt deel uit van de cursus
Joining Data with data.table in R
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Right join
subjects[___]