hemm

Computes a matrix-matrix product where one input matrix is Hermitian and one is general.

hemm supports the following precisions:

T
std::complex<float>
std::complex<double>

Description

The hemm routines compute a scalar-matrix-matrix product and add the result to a scalar-matrix product, where one of the matrices in the multiplication is Hermitian. The argument left_right determines if the Hermitian matrix, A, is on the left of the multiplication (left_right = side::left) or on the right (left_right = side::right). Depending on left_right, the operation is defined as

C <- alpha*A*B + beta*C

or

C <- alpha*B*A + beta*C

where:

alpha and beta are scalars,

A is a Hermitian matrix, either m-by-m or n-by-n matrices,

B and C are m-by-n matrices.

hemm (Buffer Version)

Syntax

void onemkl::blas::hemm(sycl::queue &queue, onemkl::side left_right, onemkl::uplo upper_lower, std::int64_t m, std::int64_t n, T alpha, sycl::buffer<T, 1> &a, std::int64_t lda, sycl::buffer<T, 1> &b, std::int64_t ldb, T beta, sycl::buffer<T, 1> &c, std::int64_t ldc)

Input Parameters

queue

The queue where the routine should be executed.

left_right

Specifies whether A is on the left side of the multiplication (side::left) or on the right side (side::right). See oneMKL defined datatypes for more details.

uplo

Specifies whether A’s data is stored in its upper or lower triangle. See oneMKL defined datatypes for more details.

m

Specifies the number of rows of the matrix B and C.

The value of m must be at least zero.

n

Specifies the number of columns of the matrix B and C.

The value of n must be at least zero.

alpha

Scaling factor for the matrix-matrix product.

a

Buffer holding input matrix A. Must have size at least lda*m if A is on the left of the multiplication, or lda*n if A is on the right. See Matrix and Vector Storage for more details.

lda

Leading dimension of A. Must be at least m if A is on the left of the multiplication, or at least n if A is on the right. Must be positive.

b

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

ldb

Leading dimension of B. Must be positive and at least m.

beta

Scaling factor for matrix C.

c

Buffer holding input/output matrix C. Must have size at least ldc*n. See Matrix and Vector Storage for more details.

ldc

Leading dimension of C. Must be positive and at least m.

Output Parameters

c

Output buffer, overwritten by alpha*A*B + beta*C (left_right = side::left) or alpha*B*A + beta*C (left_right = side::right).

Notes

If beta = 0, matrix C does not need to be initialized before calling hemm.

hemm (USM Version)

Syntax

sycl::event onemkl::blas::hemm(sycl::queue &queue, onemkl::side left_right, onemkl::uplo upper_lower, std::int64_t m, std::int64_t n, T alpha, const T *a, std::int64_t lda, const T *b, std::int64_t ldb, T beta, T *c, std::int64_t ldc, const sycl::vector_class<sycl::event> &dependencies = {})

Input Parameters

queue

The queue where the routine should be executed.

left_right

Specifies whether A is on the left side of the multiplication (side::left) or on the right side (side::right). See oneMKL defined datatypes for more details.

uplo

Specifies whether A’s data is stored in its upper or lower triangle. See oneMKL defined datatypes for more details.

m

Specifies the number of rows of the matrix B and C.

The value of m must be at least zero.

n

Specifies the number of columns of the matrix B and C.

The value of n must be at least zero.

alpha

Scaling factor for the matrix-matrix product.

a

Pointer to input matrix A. Must have size at least lda*m if A is on the left of the multiplication, or lda*n if A is on the right. See Matrix and Vector Storage for more details.

lda

Leading dimension of A. Must be at least m if A is on the left of the multiplication, or at least n if A is on the right. Must be positive.

b

Pointer to input matrix B. Must have size at least ldb*n. See Matrix and Vector Storage for more details.

ldb

Leading dimension of B. Must be positive and at least m.

beta

Scaling factor for matrix C.

c

Pointer to input/output matrix C. Must have size at least ldc*n. See Matrix and Vector Storage for more details.

ldc

Leading dimension of C. Must be positive and at least m.

dependencies

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

Output Parameters

c

Pointer to the output matrix, overwritten by alpha*A*B + beta*C (left_right = side::left) or alpha*B*A + beta*C (left_right = side::right).

Notes

If beta = 0, matrix C does not need to be initialized before calling hemm.

Return Values

Output event to wait on to ensure computation is complete.

Parent topic: BLAS Level 3 Routines