[R] Filling empty List in a FOR LOOP

[MacQueen, Don]

Try

  A[[1]] <- NA

(It is of course up to you to do the tests, presumably using if(), to
decide when to assign NA to the list element.)

-Don

-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 3/31/12 7:53 PM, "michaelyb" <cel81009759 at gmail.com> wrote:

>Hello all,
>
>I am trying to automate a list to be filled in a FOR LOOP.
>Basically I need to load info from a third source and store it into a
>list.
>This list goes to object "A"; The next list brought in by the LOOP goe to
>object "B".. os on ans so forth.
>
>When the iteration on the LOOP goes well (which means it isn't empty) I
>get
>something like this:
>
>A       
>[[1]]
>      [,1]   
> [1,] "1130"
> [2,] "1132"
> [3,] "1134"
> [4,] "1136"
> [5,] "1138"
> [6,] "1140"
> [7,] "1142"
> 
>[[2]]
>      [,1]  
> [1,] "7.54"
> [2,] "6.55"
> [3,] "4.20"
> [4,] "3.50"
> [5,] "2.92"
> [6,] "2.42"
> [7,] "1.99"
>
>However when the source is empty I get the following:
>
>A
>[[1]]
>     [,1]
>
>[[2]]
>     [,1]
>
>I need to store NA in the latter one. I have tried A[is.na(A)] but I get
>an
>error message. 
>Any help would be greatly appreciated.
>
>Thank you in advance
>
>--
>View this message in context:
>http://r.789695.n4.nabble.com/Filling-empty-List-in-a-FOR-LOOP-tp4522694p4
>522694.html
>Sent from the R help mailing list archive at Nabble.com.
>
>______________________________________________
>R-help at r-project.org mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.