num::kernel::gbmv

Defined in header <kernel/dense.hpp>

template <std::floating_point T>
void gbmv(T *y, T alpha, const T *ab, idx ldab, idx kl, idx ku, const T *x, T beta,
          idx n) noexcept;

Computes banded matrix-vector multiplication \(\mathbf{y} \leftarrow \alpha A \mathbf{x} + \beta \mathbf{y}\) in LAPACK band storage (BLAS GBMV).