Computes a matrix-vector product with a general band matrix.
void gbmv(queue &exec_queue, transpose trans, std::int64_t m, std::int64_t n, std::int64_t kl, std::int64_t ku, T alpha, buffer<T,1> &a, std::int64_t lda, buffer<T,1> &x, std::int64_t incx, T beta, buffer<T,1> &y, std::int64_t incy);
gbmv supports the following precisions and devices.
T | Devices Supported |
---|---|
float | Host, CPU, and GPU |
double | Host, CPU, and GPU |
std::complex<float> | Host, CPU, and GPU |
std::complex<double> | Host, CPU, and GPU |
The gbmv routines compute a scalar-matrix-vector product and add the result to a scalar-vector product, with a general band matrix. The operation is defined as
y <- alpha*op(A)*x + beta*y
where:
op(A) is one of op(A) = A, or op(A) = AT, or op(A) = AH,
alpha and beta are scalars,
A is an m-by-n matrix with kl sub-diagonals and ku super-diagonals,
x and y are vectors.
The queue where the routine should be executed.
Specifies op(A), the transposition operation applied to A. See Data Types for more details.
Number of rows of A. Must be at least zero.
Number of columns of A. Must be at least zero.
Number of sub-diagonals of the matrix A. Must be at least zero.
Number of super-diagonals of the matrix A. Must be at least zero.
Scaling factor for the matrix-vector product.
The array holding input matrix A must have size at least lda*n if column major layout is used, or at least lda*m if row major layout is used.
Leading dimension of matrix A. Must be at least (kl + ku + 1), and positive.
Buffer holding input vector x. The length len of vector x is n if A is not transposed, and m if A is transposed. The buffer must be of size at least (1 + (len - 1)*abs(incx)). See Matrix and Vector Storage for more details.
Stride of vector x.
Scaling factor for vector y.
Buffer holding input/output vector y. The length len of vector y is m, if A is not transposed, and n if A is transposed. The buffer must be of size at least (1 + (len - 1)*abs(incy)) where len is this length. See Matrix and Vector Storage for more details.
Stride of vector y.
Buffer holding the updated vector y.