symm
Contents
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:
or
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>
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
andC
. The value ofm
must be at least zero.- n
Number of columns of
B
andC
. The value ofn
must be at least zero.- alpha
Scaling factor for the matrix-matrix product.
- a
Buffer holding input matrix
A
. Must have size at leastlda
*m
ifA
is on the left of the multiplication, orlda
*n
ifA
is on the right. See Matrix Storage for more details.- lda
Leading dimension of
A
. Must be at leastm
ifA
is on the left of the multiplication, or at leastn
ifA
is on the right. Must be positive.- b
Buffer holding input matrix
B
. Must have size at leastldb
*n
if column major layout is used to store matrices or at leastldb
*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 leastm
if column major layout is used to store matrices or at leastn
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 leastldc
*n
if column major layout is used to store matrices or at leastldc
*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 leastm
if column major layout is used to store matrices or at leastn
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
) oralpha
*B
*A
+beta
*C
(left_right
=side::right
).
Notes
If beta
= 0, matrix C
does not need to be initialized before
calling symm
.
Throws
This routine shall throw the following exceptions if the associated condition is detected. An implementation may throw additional implementation-specific exception(s) in case of error conditions not covered here.
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
andC
. The value ofm
must be at least zero.- n
Number of columns of
B
andC
. The value ofn
must be at least zero.- alpha
Scaling factor for the matrix-matrix product.
- a
Pointer to input matrix
A
. Must have size at leastlda
*m
ifA
is on the left of the multiplication, orlda
*n
ifA
is on the right. See Matrix Storage for more details.- lda
Leading dimension of
A
. Must be at leastm
ifA
is on the left of the multiplication, or at leastn
ifA
is on the right. Must be positive.- b
Pointer to input matrix
B
. Must have size at leastldb
*n
if column major layout is used to store matrices or at leastldb
*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 leastm
if column major layout is used to store matrices or at leastn
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 leastldc
*n
if column major layout is used to store matrices or at leastldc
*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 leastm
if column major layout is used to store matrices or at leastn
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
) oralpha
*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.
Throws
This routine shall throw the following exceptions if the associated condition is detected. An implementation may throw additional implementation-specific exception(s) in case of error conditions not covered here.
oneapi::mkl::unsupported_device
Parent topic: BLAS Level 3 Routines