Great!
Thanks a lot, Enrico


2013/4/2 Duncan Murdoch <murdoch.duncan@gmail.com>

> On 02/04/2013 6:36 AM, Enrico Bibbona wrote:
>
>> Is there any function that extends to multidimentional arrays the
>> functionalities of "row" and "col" which are just defined for matrices?
>> Thanks, Enrico Bibbona
>>
>
> Not as far as I know, but there are a lot of functions in packages.
>
> You could write your own something like this.  I've skipped any error
> checking; you'll want to add that.
>
> indices <- function(a, which) {
>   d <- dim(a)
>   prod_before <- prod(d[seq_len(which-1)])
>   result <- rep(seq_len(d[which]), each=prod_before,  length.out = prod(d))
>   dim(result) <- d
>   result
> }
>
> Then indices(a, 1) gives an array of the same shape as a where entry i, j,
> k, ... is i, indices(a, 2) has entry i,j,k, ... equal to j, etc.
>
> Duncan Murdoch
>
>

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