using R - delete rows when a value repeated less than 3 times

Question

frame with 10 rows and 3 columns

    a   b c
1   1 201 1
2   2 202 1
3   3 203 1
4   4 204 1
5   5 205 4
6   6 206 5
7   7 207 4
8   8 208 4
9   9 209 8
10 10 210 5

I want to delete all rows where the same value in the column "c" repeated less than 3 times. In this example I want to remove rows 6, 9 and 10. (my real data.frame has 5000 rows and 25 cols) I tried to do it using the function rle, but I keep getting the wrong solution. any help? thanks!

Answer 1

Here is a solution using ave :

Data[ave(Data$c, Data$c, FUN = length) > 2, ]

or using ave with subset:

subset(Data, ave(c, c, FUN = length) > 2)

Answer 2

Building on Joshua's answer:

Data[Data$c %in% names(which(table(Data$c) > 2)), ]