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). Depending on left_right, the operation is defined as:

\[C \leftarrow alpha*A*B + beta*C\]

\[C \leftarrow alpha*B*A + beta*C\]

where:

alpha and beta are scalars,

A is a symmetric matrix, either m-by-m or n-by-n,

B and C are m-by-n matrices.

symm supports the following precisions.

T

float

double

std::complex<float>

std::complex<double>

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

symm (Buffer Version)#

Syntax

namespace oneapi::mkl::blas::column_major {
    void symm(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)
}

namespace oneapi::mkl::blas::row_major {
    void symm(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.
upper_lower: Specifies whether A’s data is stored in its upper or lower triangle. See oneMKL Defined Datatypes for more details.
m: Number of rows of B and C. The value of m must be at least zero.
n: Number of columns of 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 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 if column major layout is used to store matrices or at least ldb*m if row major layout is used to store matrices. See Matrix Storage for more details.
ldb: Leading dimension of B. It must be positive and at least m if column major layout is used to store matrices or at least n if column major layout is used to store matrices.
beta: Scaling factor for matrix C.
c: The buffer holding the input/output matrix C. It must have a size of at least ldc*n if column major layout is used to store matrices or at least ldc*m if row major layout is used to store matrices. See Matrix Storage for more details.
ldc: The leading dimension of C. It must be positive and at least m if column major layout is used to store matrices or at least n if column major layout is used to store matrices.

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 symm.

symm (USM Version)#

Syntax

namespace oneapi::mkl::blas::column_major {
    sycl::event symm(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 std::vector<sycl::event> &dependencies = {})
}

namespace oneapi::mkl::blas::row_major {
    sycl::event symm(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 std::vector<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.
upper_lower: Specifies whether A’s data is stored in its upper or lower triangle. See oneMKL Defined Datatypes for more details.
m: Number of rows of B and C. The value of m must be at least zero.
n: Number of columns of 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 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 if column major layout is used to store matrices or at least ldb*m if row major layout is used to store matrices. See Matrix Storage for more details.
ldb: Leading dimension of B. It must be positive and at least m if column major layout is used to store matrices or at least n if column major layout is used to store matrices.
beta: Scaling factor for matrix C.
c: The pointer to input/output matrix C. It must have a size of at least ldc*n if column major layout is used to store matrices or at least ldc*m if row major layout is used to store matrices . See Matrix Storage for more details.
ldc: The leading dimension of C. It must be positive and at least m if column major layout is used to store matrices or at least n if column major layout is used to store matrices.
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 symm.

Return Values

Output event to wait on to ensure computation is complete.

Parent topic: BLAS Level 3 Routines

symm

Contents

symm#

symm (Buffer Version)#

symm (USM Version)#