symm

Intel® oneAPI Math Kernel Library (oneMKL) - Data Parallel C++ Developer Reference

Download PDF

ID 772045

Date 12/16/2022

Version

Public

A newer version of this document is available. Customers should click here to go to the newest version.

Visible to Intel only — GUID: GUID-4723664A-B470-4060-A345-34C50E0B0AD1

View Details

symm

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

Description

The symm 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 symmetric. The argument left_right determines if the symmetric matrix A is on the left of the multiplication (left_right = side::left) or on the right (left_right = side::right). The operation is defined as:

If (left_right = side::left),

If (left_right = side::right),

where:

alpha and beta are scalars
A is either m x m or n x n symmetric matrix
B and C are m x n matrices

symm supports the following precisions:

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

symm (Buffer Version)

Syntax

namespace oneapi::mkl::blas::column_major {
    void symm(sycl::queue &queue,
              oneapi::mkl::side left_right,
              oneapi::mkl::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,
              compute_mode mode = compute_mode::unset)
}

namespace oneapi::mkl::blas::row_major {
    void symm(sycl::queue &queue,
              oneapi::mkl::side left_right,
              oneapi::mkl::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,
              compute_mode mode = compute_mode::unset)
}

Input Parameters

queue: The queue where the routine should be executed.
left_right: Specifies whether matrix A is on the left side or right side of the multiplication. See Data Types for more details.
upper_lower: Specifies whether matrix A is upper or lower triangular. See Data Types for more details.
m: Number of rows of matrix B and matrix C. Must be at least zero.
n: Number of columns of matrix B and matrix C. Must be at least zero.
alpha: Scaling factor for matrix-matrix product.
a: Buffer holding input matrix A. Size of the buffer must be at least lda * m if left_right = side::left or lda * n if left_right = side::right. See Matrix Storage for more details.
lda: Leading dimension of matrix A. Must be at least m if left_right = side::left or at least n if left_right = side::right. Must be positive.
b: Buffer holding input matrix B. Size of the buffer must be at least ldb * n if column major layout or at least ldb * m if row major layout is used. See Matrix Storage for more details.
ldb: Leading dimension of matrix B. Must be at least m if column major layout or at least n if row major layout is used. Must be positive.
beta: Scaling factor for matrix C.
c: Buffer holding input/output matrix C. Size of the buffer must be at least ldc * n if column major layout or at least ldc * m if row major layout is used. See Matrix Storage for more details.
ldc: Leading dimension of matrix C. Must be at least m if column major layout or at least n if row major layout is used. Must be positive.
mode: Optional. Compute mode settings. See Compute Modes for more details.

Output Parameters

c: Output buffer overwritten by alpha * A * B + beta * C if left_right = side::left or alpha * B * A + beta * C if left_right = side::right.

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

symm (USM Version)

Syntax

namespace oneapi::mkl::blas::column_major {
    sycl::event symm(sycl::queue &queue,
                     oneapi::mkl::side left_right,
                     oneapi::mkl::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,
                     compute_mode mode = compute_mode::unset,
                     const std::vector<sycl::event> &dependencies = {})
}

namespace oneapi::mkl::blas::row_major {
    sycl::event symm(sycl::queue &queue,
                     oneapi::mkl::side left_right,
                     oneapi::mkl::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,
                     compute_mode mode = compute_mode::unset,
                     const std::vector<sycl::event> &dependencies = {})
}

Input Parameters

queue

The queue where the routine should be executed.

left_right

Specifies whether matrix A is on the left side or right side of the multiplication. See Data Types for more details.

upper_lower

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

m

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

n

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

alpha

Scaling factor for matrix-matrix product.

a

Pointer to input matrix A. Size of the array must be at least lda * m if left_right = side::left or lda * n if left_right = side::right. See Matrix Storage for more details.

lda

Leading dimension of matrix A. Must be at least m if left_right = side::left or at least n if left_right = side::right. Must be positive.

b

Pointer to input matrix B. Size of the array must be at least ldb * n if column major layout or at least ldb * m if row major layout is used. See Matrix Storage for more details.

ldb

Leading dimension of matrix B. Must be at least m if column major layout or at least n if row major layout is used. Must be positive.

beta

Scaling factor for matrix C.

c

Pointer to input/output matrix C. Size of the array must be at least ldc * n if column major layout or at least ldc * m if row major layout is used. See Matrix Storage for more details.

ldc

Leading dimension of matrix C. Must be at least m if column major layout or at least n if row major layout is used. Must be positive.

mode

Optional. Compute mode settings. See Compute Modes for more details.

dependencies

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

mode and dependencies may be omitted independently; it is not necessary to specify mode in order to provide dependencies.

Output Parameters

c: Pointer to output matrix overwritten by alpha * A * B + beta * C if left_right = side::left or alpha * B * A + beta * C if left_right = side::right.

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

Return Values

Output event to wait on to ensure computation is complete.

Select Your Language

Using Intel.com Search

Quick Links

Recent Searches

Advanced Search

Only search in

Intel® oneAPI Math Kernel Library (oneMKL) - Data Parallel C++ Developer Reference

symm

Description

symm (Buffer Version)

symm (USM Version)