On Mon, Jun 21, 2010 at 11:45 PM, Eric Shamay <eric.shamay@gmail.com> wrote:

I've been trying to form a class based on the matrix_slice to ease some operations. Thus far I have: http://codepad.org/EepVDx2C

The compiler complains about the line where I form a matrix_slice (line 21 in the paste), and specifically with the first argument. I'm lost as to why I can't submit a matrix<double> as the first argument in the manner I've tried.

Any help would be greatly appreciated.

Hi! The matrix_slice constructor takes either a "matrix_type&" or a "matrix_closure_type const&" as first parameter. In case of the "matrix_closure_type const&" version, this is translated into const matrix_reference<matrix<double> const> for the "matrix_t" type. On line 21, you're passing a "const Tensor&", so the compiler is unable to find a good match. I think a possible solution (maybe not the better one) is to replace line 21 with the following: return submatrix(*const_cast<Tensor*>(this), slice(s1, 1, e1), slice(s2, 1, e2)); Substantially, you remove the constness from "this" and pass to the "matrix_slice" ctor a "matrix_t&" parameter. -- Marco