trmv

Computes a matrix-vector product using a triangular matrix.

Description

The trmv routines compute a matrix-vector product with a triangular matrix. The operation is defined

\[x \leftarrow op(A)*x\]

where:

  • op(A) is one of op(A) = A, or op(A) = AT, or op(A) = AH,

  • A is an n-by-n unit or non-unit, upper or lower triangular band matrix,

  • x is a vector of length n.

API

Syntax

namespace oneapi::mkl::blas::column_major {
    void trmv(sycl::queue &queue,
              onemkl::uplo upper_lower,
              onemkl::transpose trans,
              onemkl::diag unit_nonunit,
              std::int64_t n,
              sycl::buffer<T,1> &a,
              std::int64_t lda,
              sycl::buffer<T,1> &x,
              std::int64_t incx)
}
namespace oneapi::mkl::blas::row_major {
    void trmv(sycl::queue &queue,
              onemkl::uplo upper_lower,
              onemkl::transpose trans,
              onemkl::diag unit_nonunit,
              std::int64_t n,
              sycl::buffer<T,1> &a,
              std::int64_t lda,
              sycl::buffer<T,1> &x,
              std::int64_t incx)
}

trmv 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

Input Parameters

exec_queue

The queue where the routine should be executed.

upper_lower

Specifies whether A is upper or lower triangular. See Data Types for more details.

trans

Specifies op(A), the transposition operation applied to A. See Data Types for more details.

unit_nonunit

Specifies whether the matrix A is unit triangular or not. See Data Types for more details.

n

Numbers of rows and columns of A. Must be at least zero.

a

Buffer holding input matrix A. Must have size at least lda*n. See Matrix and Vector Storage for more details.

lda

Leading dimension of matrix A. Must be at least n, and positive.

x

Buffer holding input vector x. The buffer must be of size at least (1 + (n - 1)*abs(incx)). See Matrix and Vector Storage for more details.

incx

Stride of vector x.

Output Parameters

x

Buffer holding the updated vector x.