[Rcpp-devel] Is there an Rcpp class for arrays with > 2 dimensions?

[Romain Francois]

(cc'ing the list since apparently you did not)

Le 15/06/10 21:50, Dominick Samperi a écrit :
> On Tue, Jun 15, 2010 at 3:11 PM, Romain Francois
> <romain at r-enthusiasts.com <mailto:romain at r-enthusiasts.com>> wrote:
>
>     which looks about right. although not much useful without some more
>     support such as extract or set the values.
>
>         But there seems to be a problem due to non-public fields.
>
>     What do you mean ?
>
>
> I looked at my code again and what I actually tried to do was:
>
> #include <Rcpp.h>
> RcppExport SEXP multidim() {
>      BEGIN_RCPP
>      Rcpp::NumericMatrix nv(Rcpp::Dimension(2,3,4));
>      return nv;
>      END_RCPP
> }
>
> So I incorrectly used NumericMatrix instead of NumericVector, and this
> will not compile. Switching to NumericVector works.
>
> So I guess what you are saying is that the multi-dimensional "matrix"
> support present but not yet complete.
>
> Thanks,
> Dominick

That makes sense, in R a matrix is of dimension 2, not 1, not 3, just 2.

What Doug was looking for is an Rcpp class representing an R __array__, 
which have any number of dimensions.

There is currently no Rcpp::Array class, this is not complicated code to 
write, we just need to find someone with enough motivation.

Tomorrow is another day, so maybe tomorrow me will do it.

Romain

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