.rst .pdf

Contents

syrk

Performs a symmetric rank-k update.

Description

The syrk routines perform a rank-k update of a symmetric matrix C by a general matrix A. The operation is defined as:

where:

• op(X) is one of op(X) = X or op(X) = X^T

• alpha and beta are scalars

• C is n x n symmetric matrix,

• op(A) is n x k general matrix

syrk supports the following precisions:

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

syrk (Buffer Version)

Syntax

namespace oneapi::mkl::blas::column_major {
    void syrk(sycl::queue &queue,
              oneapi::mkl::uplo upper_lower,
              oneapi::mkl::transpose trans,
              std::int64_t n,
              std::int64_t k,
              T alpha,
              sycl::buffer<T,1> &a,
              std::int64_t lda,
              T beta,
              sycl::buffer<T,1> &c,
              std::int64_t ldc)
}

namespace oneapi::mkl::blas::row_major {
    void syrk(sycl::queue &queue,
              oneapi::mkl::uplo upper_lower,
              oneapi::mkl::transpose trans,
              std::int64_t n,
              std::int64_t k,
              T alpha,
              sycl::buffer<T,1> &a,
              std::int64_t lda,
              T beta,
              sycl::buffer<T,1> &c,
              std::int64_t ldc)
}

Input Parameters

queue

The queue where the routine should be executed.

upper_lower

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

trans

Specifies op(A), the transposition operation applied to matrix A. Conjugation is never performed even if trans = transpose::conjtrans. See Data Types for more details.

n

Number of rows and columns of matrix C. Must be at least zero.

k

Number of columns of matrix op(A). Must be at least zero.

alpha

Scaling factor for the rank-k update.

a

Buffer holding input matrix A. See Matrix Storage for more details.

	trans = transpose::nontrans	trans = transpose::trans or trans = transpose::conjtrans
Column major	A is n x k matrix. Size of array a must be at least lda * k	A is k x n matrix. Size of array a must be at least lda * n
Row major	A is n x k matrix. Size of array a must be at least lda * n	A is k x n matrix. Size of array a must be at least lda * k

lda

Leading dimension of matrix A. Must be positive.

	trans = transpose::nontrans	trans = transpose::trans or trans = transpose::conjtrans
Column major	Must be at least n	Must be at least k
Row major	Must be at least k	Must be at least n

beta

Scaling factor for matrix C.

c

Buffer holding input/output matrix C. Size of the buffer must be at least ldc * n. See Matrix Storage for more details.

ldc

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

Output Parameters

c

Output buffer overwritten by alpha * op(A) * op(A)^T + beta * C.

syrk (USM Version)

Syntax

namespace oneapi::mkl::blas::column_major {
    sycl::event syrk(sycl::queue &queue,
                     oneapi::mkl::uplo upper_lower,
                     oneapi::mkl::transpose trans,
                     std::int64_t n,
                     std::int64_t k,
                     T alpha,
                     const T* a,
                     std::int64_t lda,
                     T beta,
                     T* c,
                     std::int64_t ldc,
                     const std::vector<sycl::event> &dependencies = {})
}

namespace oneapi::mkl::blas::row_major {
    sycl::event syrk(sycl::queue &queue,
                     oneapi::mkl::uplo upper_lower,
                     oneapi::mkl::transpose trans,
                     std::int64_t n,
                     std::int64_t k,
                     T alpha,
                     const T* a,
                     std::int64_t lda,
                     T beta,
                     T* c,
                     std::int64_t ldc,
                     const std::vector<sycl::event> &dependencies = {})
}

Input Parameters

queue

The queue where the routine should be executed.

upper_lower

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

trans

Specifies op(A), the transposition operation applied to matrix A. Conjugation is never performed even if trans = transpose::conjtrans. See Data Types for more details.

n

Number of rows and columns of matrix C. Must be at least zero.

k

Number of columns of matrix op(A). Must be at least zero.

alpha

Scaling factor for the rank-k update.

a

Pointer to input matrix A. See Matrix Storage for more details.

	trans = transpose::nontrans	trans = transpose::trans or trans = transpose::conjtrans
Column major	A is n x k matrix. Size of array a must be at least lda * k	A is k x n matrix. Size of array a must be at least lda * n
Row major	A is n x k matrix. Size of array a must be at least lda * n	A is k x n matrix. Size of array a must be at least lda * k

lda

Leading dimension of matrix A. Must be positive.

	trans = transpose::nontrans	trans = transpose::trans or trans = transpose::conjtrans
Column major	Must be at least n	Must be at least k
Row major	Must be at least k	Must be at least n

beta

Scaling factor for matrix C.

c

Pointer to input/output matrix C. Size of the array must be at least ldc * n. See Matrix Storage for more details.

ldc

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

dependencies

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

Output Parameters

c

Pointer to output matrix, overwritten by alpha * op(A) * op(A)^T + beta * C.

Return Values

Output event to wait on to ensure computation is complete.

syr2k trmm