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her
Computes a rank-1 update of a hermitian matrix.
Description
The her routines compute a scalar-vector-vector product and add the result to a hermitian matrix. The operation is defined as:
where:
alpha is scalar
A is n x n hermitian matrix
x is a vector of length n
her supports the following precisions:
T |
Treal |
|---|---|
std::complex<float> |
float |
std::complex<double> |
double |
her (Buffer Version)
Syntax
namespace oneapi::mkl::blas::column_major {
void her(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
Treal alpha,
sycl::buffer<T,1> &x,
std::int64_t incx,
sycl::buffer<T,1> &a,
std::int64_t lda)
}
namespace oneapi::mkl::blas::row_major {
void her(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
Treal alpha,
sycl::buffer<T,1> &x,
std::int64_t incx,
sycl::buffer<T,1> &a,
std::int64_t lda)
}
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.
- a
-
Buffer holding input matrix A. Size of the buffer must be at least lda * n. See Matrix Storage for more details.
- lda
-
Leading dimension of matrix A. Must be at least n and positive.
Output Parameters
- a
-
Buffer holding updated upper triangular part of the hermitian matrix A if upper_lower=upper or updated lower triangular part of the hermitian matrix A if upper_lower=lower.
If alpha is zero, A matrix is unchanged, otherwise imaginary parts of the diagonal elements are set to zero.
her (USM Version)
Syntax
namespace oneapi::mkl::blas::column_major {
sycl::event her(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
Treal alpha,
const T *x,
std::int64_t incx,
T *a,
std::int64_t lda,
const std::vector<sycl::event> &dependencies = {})
}
namespace oneapi::mkl::blas::row_major {
sycl::event her(sycl::queue &queue,
oneapi::mkl::uplo upper_lower,
std::int64_t n,
Treal alpha,
const T *x,
std::int64_t incx,
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 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
-
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.
- a
-
Pointer to input matrix A. Size of the array holding input matrix A must be at least lda * n. See Matrix Storage for more details.
- lda
-
Leading dimension of matrix A. Must be at least n 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 updated upper triangular part of the hermitian matrix A if upper_lower=upper or updated lower triangular part of the hermitian matrix A if upper_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.