[R] creating list of lists

[Ben Tupper]

Hello,

On Mar 12, 2011, at 8:32 AM, Maas James Dr (MED) wrote:

> Question 1:
> I have a long list of variable names such as
>
> first <- c("one","two","three")
>
> and what I want to do is create a list of lists ... where the names  
> of each of overall lists components are  "one","two", and "three".
>
> This is the same result as
>
> second <- list(one=list(),two=list(),three=list())
>
> Is there a way to exploit lapply to convert a list such as first to  
> a list of empty lists such as second?
>

The first question is relatively easy.  Try...

first <- c("one","two","three")
second <- sapply(first, function(x) { vector(mode = "list") })

I am unable to help you with your second question.

Cheers,
Ben

> Question 2:
>
> In a parallel routine using foreach and doMPI have to put calcualted  
> values into a list of lists such as
>
> list(one=one,
>     two=two,
>     three=three)
>
> It uses the same (large) list of variable names as first in question  
> 1.  Is there a simpler way to accomplish this with a lapply statement?
>
>
> I've tried several permutations but no luck! Thanks a bunch.
>
> Jim
>
> ===============================
> Dr. Jim Maas
> University of East Anglia
>
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Ben Tupper
Bigelow Laboratory for Ocean Sciences
180 McKown Point Rd. P.O. Box 475
West Boothbay Harbor, Maine   04575-0475
http://www.bigelow.org/