Accessing and subsetting data frames (1)
Even more often than with vectors, you are going to want to subset your data frame or access certain columns. Again, one of the ways to do this is to use [ ]. The notation is just like matrices! Here are some examples:
Select the first row: cash[1, ]
Select the first column: cash[ ,1]
Select the first column by name: cash[ ,"company"]
Deze oefening maakt deel uit van de cursus
Introduction to R for Finance
Oefeninstructies
- Select the third row and second column of
cash. - Select the fifth row of the
"year"column ofcash.
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Third row, second column
# Fifth row of the "year" column