[R] list of list

William Dunlap wdunlap at tibco.com
Mon Feb 16 20:17:21 CET 2015


You can let lapply() do the preallocation and the looping for you with

   ASL <- lapply(1:5, function(j) lapply(1:5, function(i) i^j))

Bill Dunlap
TIBCO Software
wdunlap tibco.com

On Mon, Feb 16, 2015 at 9:46 AM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us>
wrote:

> You have two named objects when your goal is to have one that contains
> five others.
>
> ASL <- vector( "list", 5 )
> for (j in 1:5){
>   ASL[[j]] <- vector( "list", 5 )
>   for (i in 1:5) {
>     ASL[[j]][[i]] <- i^j
>   }
> }
>
> ---------------------------------------------------------------------------
> Jeff Newmiller                        The     .....       .....  Go Live...
> DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
> Go...
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> ---------------------------------------------------------------------------
> Sent from my phone. Please excuse my brevity.
>
> On February 16, 2015 8:43:51 AM PST, Troels Ring <tring at gvdnet.dk> wrote:
> >Dear friends - this is simple I know but I can figure it out without
> >your help.
> >I have for each of 2195 instances 10 variables measured at specific
> >times from 6 to several hundred, so if I just take one of the
> >instances,
> >I can make a list of the 10 variables together with their variable
> >times. But when I have 2195 such instances I cannot get it how to make
> >a
> >list of these individual lists
> >
> >As a toy example demonstrating mercilessly my problem, if ASL[j] is
> >mean
> >to take the list of here 5 entries made in RES[[i]] and I write this
> >(ignoring the times) it certainly doesn't work
> >ASL <- list()
> >RES <- list()
> >for (j in 1:5){
> >for (i in 1:5)
> >ASL[[j]] <-
> >  RES[[i]] <- i^j }
> >
> >All best wishes
> >Troels Ring
> >Aalborg, Denmark
> >
> >______________________________________________
> >R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >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.
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
>

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