Drop / collapse rows

Question

Say I have a dataset like the one below:

x y z
1 9 3
3 0 3
4 0 2
1 4 1
5 1 9
4 2 3
9 0 1

I would like to to drop / collapse all the rows that are repeated based on the value in column z so that my new data set would read like this:

x y z
1 9 3
4 0 2
1 4 1
5 1 9

Rows 2 and 6 have been dropped because they contained a repeated value in z (the value of 3) I would simply like R to drop all remaining iterations of that whole row.

Answer 1

If your data is stored in data frame df, you could do something like:

df <- df[!duplicated(df$z), ]