Which R version do you have? I'm asking this because my 2.7.0 gives a
different error  message:

> x[[q]]
Error in x[[q]] : recursive indexing failed at level 2

Anyway, as Wacek said, x[[q]] is equivalent to
x[["some"]][["more"]][["not_there"]] -- and you don't have an element called
"more" in x[["some"]].

But you can use [ to do what you want (if the following is what you want).

> x[q]
$some
[1] 0.1118383

$more
[1] 0.4524315

$<NA>
NULL

KK

On Tue, Jan 13, 2009 at 12:49 PM, Gundala Viswanath <gundalav@gmail.com>wrote:

> Dear all,
>
> Suppose I have a hash created with this
>
>  x <- list()
> for (i in c('test', 'some', 'more')){
>   x[[i]] <- runif(1)
> }
>
> then I want to extract the elem of that hash with
> a vector
>
> > q <- c("some", "more", "not_there")
>
> But why this failed?
>
> > extracted <- x[[q]]
> Error in x[[q]] : subscript out of bounds
>
> we expect the output of 'extracted' to be
> a vector as well. When the key is not present
> to give "NA" in vector
>
> - Gundala Viswanath
> Jakarta - Indonesia
>
> ______________________________________________
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> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
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>

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