/*! * \brief Constructs a new sparse_reference * \param matrix The source matrix * \param i The index i of the first dimension * \param j The index j of the second dimension */ sparse_reference(matrix_type& matrix, size_t i, size_t j) : matrix(matrix), i(i), j(j) { n = matrix.find_n(i, j); matrix.unsafe_set_hint(i, j, n, matrix.get_hint(i, j, n)); ptr = &matrix.unsafe_ref_hint(n); }