R help - Jan 2009 - obtaining null components of a list

Hello everybody!
 I have a list of length 5000 whose components are (mostly) "ts"
objects,
but some these components are intentionally left empty, ie, they are
"NULL"
components of the list. My question is how can I get the position of these
null components in a effective way (I'm trying to avoid a for-if rutine).


Thanks!!!

	[[alternative HTML version deleted]]

Try this:
> x <- list(NULL, 1:10, 25, NULL, "more")
> x
[[1]]
NULL

[[2]]
 [1]  1  2  3  4  5  6  7  8  9 10

[[3]]
[1] 25

[[4]]
NULL

[[5]]
[1] "more"
> which(sapply(x, is.null))
[1] 1 4
>

On Wed, Jan 21, 2009 at 7:42 AM, diego Diego <dhabbyc at gmail.com>
wrote:
> Hello everybody!
>  I have a list of length 5000 whose components are (mostly) "ts"
objects,
> but some these components are intentionally left empty, ie, they are
"NULL"
> components of the list. My question is how can I get the position of these
> null components in a effective way (I'm trying to avoid a for-if
rutine).
>
>
> Thanks!!!
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>


-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?