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Visible to Intel only — GUID: GUID-E213DDC0-74FB-4B62-90A7-945FB1FE84C1
Visible to Intel only — GUID: GUID-E213DDC0-74FB-4B62-90A7-945FB1FE84C1
spr2
Computes a rank-2 update of a symmetric packed matrix.
Description
The spr2 routines compute two scalar-vector-vector products and add them to a symmetric packed matrix. The operation is defined as:
where:
alpha is scalar
A is n x n symmetric matrix, supplied in packed form
x and y are vectors of length n
spr2 supports the following precisions:
T |
|---|
float |
double |
spr2 (Buffer Version)
Syntax
namespace oneapi::mkl::blas::column_major { void spr2(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 spr2(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.
Output Parameters
- a
-
Buffer holding updated upper triangular part of the symmetric matrix A if upper_lower=upper or updated lower triangular part of the symmetric matrix A if upper_lower=lower.
spr2 (USM Version)
Syntax
namespace oneapi::mkl::blas::column_major { sycl::event spr2(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 spr2(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 vector x 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 vector y 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 matrix A must be at least (n*(n-1))/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 updated upper triangular part of the symmetric matrix A if upper_lower=upper or updated lower triangular part of the symmetric matrix A if upper_lower=lower.
Return Values
Output event to wait on to ensure computation is complete.