[R] Inflated Array

[Ben Bolker]

Hadassa Brunschwig <dassybr <at> gmail.com> writes:

> 
> Hi R-users!
> 
> I am trying to create a what I call inflated array (maybe there is
> already some other name for that). It is an array that changes
> dinamically its dimensions, e.g. the higher the number of third
> dimensions, the more rows in the array. 

  base R doesn't have a data structure for this: arrays in R
must not be "ragged" (i.e., every sub-array must have the
same dimensions).

  So you would need to use a list of matrices in your
example.  I don't quite know the logic that you're using
to decide what goes in each sub-table.

The basic example you give could be built 
by hand as follows:

list(1:4,matrix(5:12,byrow=TRUE,ncol=4),
         matrix(13:24,byrow=TRUE,ncol=4))

  if you had used scan() or something else to
get a long, flat vector (x) and also had
a vector (v) that indicated the number of
rows in each sub-table:

x <- 1:24
nrow <- c(1,2,3)
ncol <- 4

ind <- rep(1:length(nrow),ncol*nrow)
lapply(split(x,ind),
    matrix,ncol=ncol,byrow=TRUE)

  seems to work.

  cheers
   Ben Bolker