Removing rows in dataframe w'o duplicated values
On Nov 22, 2011, at 12:43 PM, AC Del Re wrote:
Hi,
Is there an easy way to remove dataframe rows without duplicated
values of
a specified column ('id')? e.g.,
dat <- data.frame(id = c(1,1,1,2,3,3), value = c(5,6,7,4,5,4),
value2 =
c(1,4,3,3,4,3))
dat
id value value2
1 1 5 1
2 1 6 4
3 1 7 3
4 2 4 3
5 3 5 4
6 3 4 3
> dat[ave(dat$id, dat$id, FUN=length) >1, ] id value value2 1 1 5 1 2 1 6 4 3 1 7 3 5 3 5 4 6 3 4 3
This is sample data and the real data has hundreds of rows. In this case, only row 4 does not have a duplicated id and I would like to remove it without using: dat$id[4] <- NULL Any help is appreciated! AC [[alternative HTML version deleted]]
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