# [R] List to Array

Gabor Grothendieck ggrothendieck at gmail.com
Wed Apr 5 16:15:32 CEST 2006

```Which can be written:

array(unlist(L), dim = c(dim(L[[1]]), length(L)))

On 4/5/06, Dimitris Rizopoulos <dimitris.rizopoulos at med.kuleuven.be> wrote:
> then maybe this is what you're looking for:
>
> L <- list(matrix(rnorm(6), nrow = 3), matrix(rnorm(6), nrow = 3))
> ################
> L
> array(unlist(L), dim = c(nrow(L[[1]]), ncol(L[[1]]), length(L)))
>
>
> Best,
> Dimitris
>
> ----
> Dimitris Rizopoulos
> Ph.D. Student
> Biostatistical Centre
> School of Public Health
> Catholic University of Leuven
>
> Address: Kapucijnenvoer 35, Leuven, Belgium
> Tel: +32/(0)16/336899
> Fax: +32/(0)16/337015
> Web: http://www.med.kuleuven.be/biostat/
>     http://www.student.kuleuven.be/~m0390867/dimitris.htm
>
>
> ----- Original Message -----
> From: "Werner Wernersen" <pensterfuzzer at yahoo.de>
> To: "Gabor Grothendieck" <ggrothendieck at gmail.com>
> Cc: <r-help at stat.math.ethz.ch>
> Sent: Wednesday, April 05, 2006 3:55 PM
> Subject: Re: [R] List to Array
>
>
> > Oh yes, I should give an example:
> >
> > m <- matrix(1:6,nrow=3)
> > L <- list(m,m)
> >
> > Output of L:
> > [[1]]
> >     [,1] [,2]
> > [1,]    1    4
> > [2,]    2    5
> > [3,]    3    6
> >
> > [[2]]
> >     [,1] [,2]
> > [1,]    1    4
> > [2,]    2    5
> > [3,]    3    6
> >
> >
> > I would like to transform L to and array looking like
> > this:
> > , , 1
> >
> >     [,1] [,2]
> > [1,]    1    4
> > [2,]    2    5
> > [3,]    3    6
> >
> > , , 2
> >
> >     [,1] [,2]
> > [1,]    1    4
> > [2,]    2    5
> > [3,]    3    6
> >
> >
> >> since its not clear what is desired here.
> >>
> >> On 4/5/06, Werner Wernersen <pensterfuzzer at yahoo.de>
> >> wrote:
> >> > Hi,
> >> >
> >> > this is probably the easiest thing to do but I
> >> manage
> >> > not finding the answer:
> >> > I have a list with matrices of exact same format
> >> and
> >> > headers. Now I would like to transform the list
> >> into
> >> > an normal array. What is the proper way to do
> >> this?
> >> > as.array changes the entire format and right now I
> >> > only found the method of creating a new array,
> >> going
> >> > through the entire list and copy the matrix in
> >> each
> >> > list element to the new array.
> >> >
> >> > Thanks a million for your help!
> >> >  Werner
> >> >
> >> > ______________________________________________
> >> > R-help at stat.math.ethz.ch mailing list
> >> > https://stat.ethz.ch/mailman/listinfo/r-help
> >> http://www.R-project.org/posting-guide.html
> >> >
> >>
> >
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