symv
Computes a matrix-vector product for a symmetric matrix.
Description
The
symv
routines compute a scalar-matrix-vector product and
add the result to a scalar-vector product, with a symmetric matrix.
The operation is defined as:
where:
- alphaandbetaare scalars
- Aisnxnsymmetric matrix
- xandyare vectors of lengthn
symv
supports the following precisions:T |
---|
float |
double |
symv (Buffer Version)
Syntax
namespace oneapi::mkl::blas::column_major {
void symv(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
T alpha,
sycl::buffer<T,1> &a,
std::int64_t lda,
sycl::buffer<T,1> &x,
std::int64_t incx,
T beta,
sycl::buffer<T,1> &y,
std::int64_t incy)
}
namespace oneapi::mkl::blas::row_major {
void symv(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
T alpha,
sycl::buffer<T,1> &a,
std::int64_t lda,
sycl::buffer<T,1> &x,
std::int64_t incx,
T beta,
sycl::buffer<T,1> &y,
std::int64_t incy)
}
Input Parameters
- queue
- The queue where the routine should be executed.
- upper_lower
- Specifies whether matrixAis upper or lower triangular. See Data Types for more details.
- n
- Number of rows and columns of matrixA. Must be at least zero.
- alpha
- Scaling factor for the matrix-vector product.
- a
- Buffer holding input matrixA. Size of the buffer must be at leastlda*n. See Matrix Storage for more details.
- lda
- Leading dimension of matrixA. Must be at leastnand positive.
- x
- Buffer holding input vectorx. Size of the buffer must be at least (1 + (n- 1)*abs(incx)). See Matrix Storage for more details.
- incx
- Stride of vectorx.
- y
- Buffer holding input/output vectory. Size of the buffer must be at least (1 + (n- 1)*abs(incy)). See Matrix Storage for more details.
- incy
- Stride of vectory.
Output Parameters
- y
- Buffer holding updated vectory.
symv (USM Version)
Syntax
namespace oneapi::mkl::blas::column_major {
sycl::event symv(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *a,
std::int64_t lda,
const T *x,
std::int64_t incx,
T beta,
T *y,
std::int64_t incy,
const std::vector<sycl::event> &dependencies = {})
}
namespace oneapi::mkl::blas::row_major {
sycl::event symv(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
T alpha,
const T *a,
std::int64_t lda,
const T *x,
std::int64_t incx,
T beta,
T *y,
std::int64_t incy,
const std::vector<sycl::event> &dependencies = {})
}
Input Parameters
- queue
- The queue where the routine should be executed.
- upper_lower
- Specifies whether matrixAis upper or lower triangular. See Data Types for more details.
- n
- Number of rows and columns of matrixA. Must be at least zero.
- alpha
- Scaling factor for the matrix-vector product.
- a
- Pointer to input matrixA. Size of the array holding input matrixAmust be at leastlda*n. See Matrix Storage for more details.
- lda
- Leading dimension of matrixA. Must be at leastnand positive.
- x
- Pointer to input vectorx. Size of the array holding input vectorxmust be at least (1 + (n- 1)*abs(incx)). See Matrix Storage for more details.
- incx
- Stride of vectorx.
- y
- Pointer to input/output vectory. Size of the array holding input/output vectorymust be at least (1 + (n- 1)*abs(incy)). See Matrix Storage for more details.
- incy
- Stride of vectory.
- dependencies
- List of events to wait for before starting computation, if any. If omitted, defaults to no dependencies.
Output Parameters
- y
- Pointer to updated vectory.
Return Values
Output event to wait on to ensure computation is complete.