[R] counts of elements in vector

Ali Tofigh alix.tofigh at gmail.com
Tue Mar 30 00:52:18 CEST 2010


Assume you have a vector of characters x:

> x
[1] "a" "b" "a" "d" "d" "c"

I use a function that counts the number of times each string occurs in x:

> sapply(unique(x), function(s) {sum(x == s)})
a b d c
2 1 2 1

Is there a more efficient way of doing this?

Cheers,
/Ali



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