her (USM Version)

Computes a rank-1 update of a Hermitian matrix.

Syntax

event her(queue &exec_queue, uplo upper_lower, std::int64_t n, T alpha, const T *x, std::int64_t incx, T *a, std::int64_t lda, const vector_class<event> &dependencies = {})

The USM version of her supports the following precisions and devices.

T

Devices Supported

std::complex<float>

Host, CPU, and GPU

std::complex<double>

Host, CPU, and GPU

Description

The her routines compute a scalar-vector-vector product and add the result to a Hermitian matrix. The operation is defined as

A <- alpha*x*xH + A

where:

alpha is scalar,

A is an n-by-n Hermitian matrix,

x is a vector of length n.

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.

n

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

alpha

Scaling factor for the matrix-vector product.

x

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

incx

Stride of vector x.

a

Pointer to input matrix A. The array 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.

dependencies

List of events to wait for before starting computation, if any. If omitted, defaults to no dependencies.

Output Parameters

a

Pointer to the updated upper triangular part of theHermitian matrix A if upper_lower = upper or the updated lowertriangular part of the Hermitian matrix A if upper_lower = lower.

The imaginary parts of the diagonal elementsare set to zero.

Return Values

Output event to wait on to ensure computation is complete.