[R] access sublists by a variable

[David Winsemius]

On Nov 16, 2011, at 10:16 AM, Antje Gruner wrote:

> Dear list,
>
> I'd like to access the elements of a list within another list with the
> help of a variable.
>
> dict <- list(  "24" = c(1,2,3,6,12,24,48,72,96,120,144,168,720),
>          "168" = c(1,12,24,48,72,96,120,144,168,336,504,672),
>         "8760" = c(1,24,168,730,4380,8760)
>        )
>
> dict$"24" works fine, but
>
> a <- "24"
> dict$a

I can't remember if this is a FAQ but it is certainly discussed on the  
page you would ge with

?"$"

dict[[a]]


>
> returns  NULL


>
> Unfortunately dict[a] does not work for me, because I see no  
> possibility
> to access the inner elements of list "24" in that case
> i.e. dict[a][1] returns the whole list and not the first element.
>
> What is the correct syntax to access those elements with the help of a
> variable?
> Thanks in advance
>
> Antje
>
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David Winsemius, MD
West Hartford, CT