Reading through part 1, my understanding was that the data frame would use select() and only contain the 4 columns listed. The following parts require the newly calculated column, but also additional columns that are not available if the data frame was created using select()
Reading through part 1, my understanding was that the data frame would use select() and only contain the 4 columns listed. The following parts require the newly calculated column, but also additional columns that are not available if the data frame was created using select()