A const &inverse() { if (step < 2) { V_type W = fortran_view(a); _step1(W); _step2(W); } return a; }
ViewType const & inverse() { if (step<2) { V_type W = fortran_view(V); _step1(W); _step2(W);} return V;}
VT det() { V_type W = fortran_view(V); _step1(W); _compute_det(W); return _det;}
value_type det() { V_type W = fortran_view(a); _step1(W); _compute_det(W); return _det; }