spr (USM Version)¶
Performs a rank-1 update of a symmetric packed matrix.
Description¶
The spr
routines compute a scalar-vector-vector product and add the
result to a symmetric packed matrix. The operation is defined as
where:
alpha
is scalar,A
is ann
-by-n
symmetric matrix, supplied in packed form,x
is a vector of lengthn
.
API¶
Syntax¶
namespace oneapi::mkl::blas::column_major {
sycl::event spr(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *x,
std::int64_t incx,
T *a,
const sycl::vector_class<sycl::event> &dependencies = {})
}
namespace oneapi::mkl::blas::row_major {
sycl::event spr(sycl::queue &queue,
onemkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *x,
std::int64_t incx,
T *a,
const sycl::vector_class<sycl::event> &dependencies = {})
}
The USM version of spr
supports the following precisions and devices.
T |
Devices Supported |
---|---|
|
Host, CPU, and GPU |
|
Host, CPU, and GPU |
Input Parameters¶
- exec_queue
The queue where the routine should be executed.
- upper_lower
Specifies whether
A
is upper or lower triangular. See Data Types for more details.- n
Number of rows and 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
.- a
Pointer to input matrix
A
. The array holding input matrixA
must have size at least (n
*(n
-n))/2. See Matrix Storage for more details.- 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 symmetric matrix
A
ifupper_lower =upper
, or the updated lower triangular part of the symmetric matrixA
ifupper_lower =lower
.
Return Values¶
Output event to wait on to ensure computation is complete.