[R] short-hand to avoid use of length() in subsetting vectors?
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Wed Jan 11 00:27:35 CET 2012
On Tue, Jan 10, 2012 at 6:04 PM, Eric Rupley <erupley at umich.edu> wrote:
> I suspect this is a frequently considered (and possibly asked) question, but I haven't thus far found an answer:
> For slicing a vector with x[…], is there a symbol for length(x)?
> I'm seeking a short-hand for referring to the length of vector one is trying to index.
> E.g., for a data.frame, say,
>> test.frame <-data.frame(matrix(c(1:100),ncol=10,nrow=10,byrow=T))
>> names(test.frame) <- names(islands)[1:10]
> is there a short-hand for subsetting
>  6 16 26 36 46 56 66
> that would allow one to avoid the "(length(some.dataframe$variable)-offset)"?
Sadly there is no shorthand of the (exact) type you are looking for.
You can access the data like so, however:
R> head(test.frame$Baffin, -3)
 6 16 26 36 46 56 66
I think that's as good as you're going to get, but let's see what
other suggestions pop up.
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