[R] counting numbers without replicates in a vector
sundar.dorai-raj at pdf.com
Thu Dec 16 22:50:24 CET 2004
Jun Ding wrote:
> I am just wondering if there is an easy way to count
> in a numeric vector how many numbers don't have
> For example,
> a=c(1,1,2,2,3,4,5), how can I know there are three
> numbers (3, 4 and 5) without replicates?
How about using ?table:
tab <- table(a)
unq <- names(tab)[tab == 1]
Then use as.numeric(unq) to convert the names to numbers if needed.
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