hpr2#
Performs a rank-2 update of a hermitian packed matrix.
Description#
The hpr2
routines compute two scalar-vector-vector products and add
them to a hermitian packed matrix. The operation is defined as:
where:
alpha
is a scalarA
isn
xn
hermitian matrix, supplied in packed formx
andy
are vectors of lengthn
hpr2
supports the following precisions:
T |
---|
|
|
hpr2 (Buffer Version)#
Syntax#
namespace oneapi::mkl::blas::column_major {
void hpr2(sycl::queue &queue,
oneapi::mkl::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)
}
namespace oneapi::mkl::blas::row_major {
void hpr2(sycl::queue &queue,
oneapi::mkl::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)
}
Input Parameters#
- queue
The queue where the routine should be executed.
- upper_lower
Specifies whether matrix
A
is upper or lower triangular. See Data Types for more details.- n
Number of rows and columns of matrix
A
. Must be at least zero.- alpha
Scaling factor for the matrix-vector product.
- x
Buffer holding input vector
x
. Size of the buffer must be at least (1 + (n
- 1)*abs(incx
)). See Matrix Storage for more details.- incx
Stride of vector
x
. Must not be zero.- y
Buffer holding input/output vector
y
. Size of the buffer must be at least (1 + (n
- 1)*abs(incy
)). See Matrix Storage for more details.- incy
Stride of vector
y
. Must not be zero.- a
Buffer holding input matrix
A
. Size of the buffer must be at least (n
*(n
-1))/2. See Matrix Storage for more details.The imaginary parts of the diagonal elements need not be set and are assumed to be zero.
Output Parameters#
- a
Buffer holding updated upper triangular part of the hermitian matrix
A
ifupper_lower=upper
, or updated lower triangular part of the hermitian matrixA
ifupper_lower=lower
.If
alpha
is zero,A
matrix is unchanged, otherwise imaginary parts of the diagonal elements are set to zero.
hpr2 (USM Version)#
Syntax#
namespace oneapi::mkl::blas::column_major {
sycl::event hpr2(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
oneapi::mkl::value_or_pointer<T> alpha,
const T *x,
std::int64_t incx,
const T *y,
std::int64_t incy,
T *a,
const std::vector<sycl::event> &dependencies = {})
}
namespace oneapi::mkl::blas::row_major {
sycl::event hpr2(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
oneapi::mkl::value_or_pointer<T> alpha,
const T *x,
std::int64_t incx,
const T *y,
std::int64_t incy,
T *a,
const std::vector<sycl::event> &dependencies = {})
}
Input Parameters#
- queue
The queue where the routine should be executed.
- upper_lower
Specifies whether matrix
A
is upper or lower triangular. See Data Types for more details.- n
Number of rows and columns of matrix
A
. Must be at least zero.- alpha
Scaling factor for the matrix-vector product. See Scalar Arguments for more information on the
value_or_pointer
data type.- x
Pointer to input vector
x
. Size of the array holding input vectorx
must be at least (1 + (n
- 1)*abs(incx
)). See Matrix Storage for more details.- incx
Stride of vector
x
. Must not be zero.- y
Pointer to input/output vector
y
. Size of the array holding input/output vectory
must be at least (1 + (n
- 1)*abs(incy
)). See Matrix Storage for more details.- incy
Stride of vector
y
. Must not be zero.- a
Pointer to input matrix
A
. Size of the array holding input matrixA
must be at least (n
*(n
-1))/2. See Matrix Storage for more details.The imaginary parts of the diagonal elements need not be set and are assumed to be zero.
- dependencies
List of events to wait for before starting computation, if any. If omitted, defaults to no dependencies.
Output Parameters#
- a
Pointer to updated upper triangular part of the hermitian matrix
A
ifupper_lower=upper
, or updated lower triangular part of the hermitian matrixA
ifupper_lower=lower
.If
alpha
is zero,A
matrix is unchanged, otherwise imaginary parts of the diagonal elements are set to zero.
Return Values#
Output event to wait on to ensure computation is complete.