I wrote:
> If anyone can tell me how to vectorise this, I would be glad of the lesson.
where "this" was
> strrev <-
> function (s) paste(rev(strsplit(s, character(0))[[1]]), collapse="")
Thomas Lumley <[EMAIL PROTECTED]> suggested
strrev<- function(ss) {
sapply(lapply( strsplit(ss,character(0)), rev), paste, collapse="")
}
Unfortunately, I failed to explain myself clearly, so this doesn't actually
answer the question I _meant_ to ask. For me, sticking in some variant of
'apply' means you have _failed_ to vectorise. The string reversal code in
?rev doesn't count for the same reason.
There is no reason why a built-in strrev() couldn't be as vectorised as
most built-ins, it's just not common enough to deserve a lot of effort.
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