28 Numerics library [numerics]

28.9 Basic linear algebra algorithms [linalg]

28.9.5 Tag classes [linalg.tags] Storage order tags [linalg.tags.order]

The storage order tags describe the order of elements in an mdspan with layout_blas_packed ([linalg.layout.packed]) layout.
struct column_major_t { explicit column_major_t() = default; }; inline constexpr column_major_t column_major{}; struct row_major_t { explicit row_major_t() = default; }; inline constexpr row_major_t row_major{};
column_major_t indicates a column-major order, and row_major_t indicates a row-major order.