[R] a merge() problem

[Sam Steingold]

I know it does not look very good - using the same column names to mean
different things in different data frames, but here you go:
--8<---------------cut here---------------start------------->8---
> x <- data.frame(a=c(1,2,3),b=c(4,5,6))
> y <- data.frame(b=c(1,2),a=c("a","b"))
> merge(x,y,by.x="a",by.y="b",all.x=TRUE,suffixes=c("","y"))
  a b    a
1 1 4    a
2 2 5    b
3 3 6 <NA>
Warning message:
In merge.data.frame(x, y, by.x = "a", by.y = "b", all.x = TRUE) :
  column name 'a' is duplicated in the result
--8<---------------cut here---------------end--------------->8---
why is the suffixes argument ignored?
I mean, I expected that the second "a" to be "a.y".
(when I omit suffixes, the result is the same).
Thanks.
-- 
Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000
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