her2#
Computes a rank-2 update of a Hermitian matrix.
Description
The her2
routines compute two scalar-vector-vector products and add
them to a Hermitian matrix. The operation is defined as:
where:
alpha
is a scalar,
A
is an n
-by-n
Hermitian matrix,
x
and y
are vectors or length n
.
her2
supports the following precisions.
T
std::complex<float>
std::complex<double>
her2 (Buffer Version)#
Syntax
namespace oneapi::mkl::blas::column_major {
void her2(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
sycl::buffer<T,1> &x,
std::int64_t incx,
sycl::buffer<T,1> &y,
std::int64_t incy,
sycl::buffer<T,1> &a,
std::int64_t lda)
}
namespace oneapi::mkl::blas::row_major {
void her2(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
sycl::buffer<T,1> &x,
std::int64_t incx,
sycl::buffer<T,1> &y,
std::int64_t incy,
sycl::buffer<T,1> &a,
std::int64_t lda)
}
Input Parameters
- queue
The queue where the routine should be executed.
- upper_lower
Specifies whether
A
is upper or lower triangular. See oneMKL Defined Datatypes for more details.- n
Number of columns of
A
. Must be at least zero.- alpha
Scaling factor for the matrix-vector product.
- x
Buffer holding input vector
x
. The buffer must be of size at least (1 + (n
- 1)*abs(incx
)). See Matrix Storage for more details.- incx
Stride of vector
x
.- y
Buffer holding input/output vector
y
. The buffer must be of size at least (1 + (n
- 1)*abs(incy
)). See Matrix Storage for more details.- incy
Stride of vector
y
.- a
Buffer holding input matrix
A
. Must have size at leastlda
*n
. See Matrix Storage for more details.- lda
Leading dimension of matrix
A
. Must be at leastn
, and positive.
Output Parameters
- a
Buffer holding the updated upper triangular part of the Hermitian matrix
A
ifupper_lower
=upper
, or the updated lower triangular part of the Hermitian matrixA
ifupper_lower
=lower
.The imaginary parts of the diagonal elements are set to zero.
her2 (USM Version)#
Syntax
namespace oneapi::mkl::blas::column_major {
sycl::event her2(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *x,
std::int64_t incx,
const T *y,
std::int64_t incy,
T *a,
std::int64_t lda,
const std::vector<sycl::event> &dependencies = {})
}
namespace oneapi::mkl::blas::row_major {
sycl::event her2(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *x,
std::int64_t incx,
const T *y,
std::int64_t incy,
T *a,
std::int64_t lda,
const std::vector<sycl::event> &dependencies = {})
}
Input Parameters
- queue
The queue where the routine should be executed.
- upper_lower
Specifies whether
A
is upper or lower triangular. See oneMKL Defined Datatypes for more details.- n
Number of columns of
A
. Must be at least zero.- alpha
Scaling factor for the matrix-vector product.
- x
Pointer to input vector
x
. The array holding input vectorx
must be of size at least (1 + (n
- 1)*abs(incx
)). See Matrix Storage for more details.- incx
Stride of vector
x
.- y
Pointer to input/output vector
y
. The array holding input/output vectory
must be of size at least (1 + (n
- 1)*abs(incy
)). See Matrix Storage for more details.- incy
Stride of vector
y
.- a
Pointer to input matrix
A
. The array holding input matrixA
must have size at leastlda
*n
. See Matrix Storage for more details.- lda
Leading dimension of matrix
A
. Must be at leastn
, and positive.- dependencies
List of events to wait for before starting computation, if any. If omitted, defaults to no dependencies.
Output Parameters
- a
Pointer to the updated upper triangular part of the Hermitian matrix
A
ifupper_lower
=upper
, or the updated lower triangular part of the Hermitian matrixA
ifupper_lower
=lower
.The imaginary parts of the diagonal elements are set to zero.
Return Values
Output event to wait on to ensure computation is complete.
Parent topic: BLAS Level 2 Routines