Did you have to use a particular filename?  or extension.

I created a similar file but then could not read it back in

Steve

On Mon, Feb 13, 2012 at 6:45 AM, Djordje Bajic <je.li.bre@gmail.com> wrote:

> I've been investigating and I partially respond myself. I tried the
> packages 'bigmemory' and 'ff' and for me the latter did the work I need
> pretty straightforward. I create the array in filebacked form with the
> function ff, and it seems that the usual R indexing works well. I have yet
> to see the limitations, but I hope it helps.
>
> a foo example:
>
> myArr <- ff(NA, dim=rep(904,3), filename="arr.ffd", vmode="double")
> myMat <- matrix(1:904^2, ncol=904)
> for ( i in 1:904 ) {
>    myArr[,,i] <- myMat
> }
>
> Thanks all,
>
> 2012/2/11 Duncan Murdoch <murdoch.duncan@gmail.com>
>
> > On 12-02-10 9:12 AM, Djordje Bajic wrote:
> >
> >> Hi all,
> >>
> >> I am trying to fill a 904x904x904 array, but at some point of the loop R
> >> states that the 5.5Gb sized vector is too big to allocate. I have looked
> >> at
> >> packages such as "bigmemory", but I need help to decide which is the
> best
> >> way to store such an object. It would be perfect to store it in this
> >> "cube"
> >> form (for indexing and computation purpouses). If not possible, maybe
> the
> >> best is to store the 904 matrices separately and read them individually
> >> when needed?
> >>
> >> Never dealed with such a big dataset, so any help will be appreciated
> >>
> >> (R+ESS, Debian 64bit, 4Gb RAM, 4core)
> >>
> >
> > I'd really recommend getting more RAM, so you can have the whole thing
> > loaded in memory.  16 Gb would be nice, but even 8Gb should make a
> > substantial difference.  It's going to be too big to store as an array
> > since arrays have a limit of 2^31-1 entries, but you could store it as a
> > list of matrices, e.g.
> >
> > x <- vector("list", 904)
> > for (i in 1:904)
> >  x[[i]] <- matrix(0, 904,904)
> >
> > and then refer to entry i,j,k as x[[i]][j,k].
> >
> > Duncan Murdoch
> >
> >
> >
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@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.
>

	[[alternative HTML version deleted]]

