# could be QQ instead of QQbar.
V = VectorSpace(basis_space.base_ring(), elt.nrows()*elt.ncols())
W = V.span_of_basis( _mat2vec(s) for s in natural_basis )
# could be QQ instead of QQbar.
V = VectorSpace(basis_space.base_ring(), elt.nrows()*elt.ncols())
W = V.span_of_basis( _mat2vec(s) for s in natural_basis )