Hi Andrew,
Try
sapply(lst, "[", 2)
HTH,
Jorge
On Mon, Jul 12, 2010 at 3:12 PM, Andrew Leeser <> wrote:
> I am looking for a way to create a vector which contains the second element
> of
> every vector in the list. However, not every vector has two components, so
> I
> need to generate an NA for those missing. For example, I have created the
> following list:
>
> lst <- list(c("a", "b"), c("c"), c("d", "e"), c("f", "g"))
>
> > lst
> [[1]]
> [1] "a" "b"
> [[2]]
> [1] "c"
> [[3]]
> [1] "d" "e"
> [[4]]
> [1] "f" "g"
>
> I would like the output to be the following:
>
> > output
> [1] "b" NA "e" "g"
>
> I know I can accomplish this using a for loop, but I am wondering if
> there's a
> simple and neat way of getting this done in one step?
>
> Thanks in advance.
>
> - Andrew
>
>
>
> [[alternative HTML version deleted]]
>
>
> ______________________________________________
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>
>
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