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Visible to Intel only — GUID: GUID-5C69BA7A-4AF4-4F5E-86C6-354D563C79EC
Visible to Intel only — GUID: GUID-5C69BA7A-4AF4-4F5E-86C6-354D563C79EC
axpy
Computes a vector-scalar product and adds the result to a vector.
Description
The axpy routines compute a scalar-vector product and add the result to a vector. The operation is defined as:
where:
x and y are vectors of n elements
alpha is a scalar
axpy supports the following precisions:
T |
|---|
sycl::half |
oneapi::mkl::bfloat16 |
float |
double |
std::complex<float> |
std::complex<double> |
axpy (Buffer Version)
Syntax
namespace oneapi::mkl::blas::column_major { void axpy(sycl::queue &queue, std::int64_t n, T alpha, sycl::buffer<T,1> &x, std::int64_t incx, sycl::buffer<T,1> &y, std::int64_t incy) }
namespace oneapi::mkl::blas::row_major { void axpy(sycl::queue &queue, std::int64_t n, T alpha, sycl::buffer<T,1> &x, std::int64_t incx, sycl::buffer<T,1> &y, std::int64_t incy) }
Input Parameters
- queue
-
The queue where the routine should be executed.
- n
-
Number of elements in vector x.
- alpha
-
Specifies scalar alpha.
- 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.
- y
-
Buffer holding input 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.
Output Parameters
- y
-
Buffer holding updated vector y.
Examples
An example of how to use axpy can be found in the oneMKL installation directory, under:
share/doc/mkl/examples/sycl/blas/source/axpy.cpp
axpy (USM Version)
Syntax
namespace oneapi::mkl::blas::column_major { sycl::event axpy(sycl::queue &queue, std::int64_t n, oneapi::mkl::value_or_pointer<T> alpha, const T *x, std::int64_t incx, T *y, std::int64_t incy, const std::vector<sycl::event> &dependencies = {}) }
namespace oneapi::mkl::blas::row_major { sycl::event axpy(sycl::queue &queue, std::int64_t n, oneapi::mkl::value_or_pointer<T> alpha, const T *x, std::int64_t incx, T *y, std::int64_t incy, const std::vector<sycl::event> &dependencies = {}) }
Input Parameters
- queue
-
The queue where the routine should be executed.
- n
-
Number of elements in vector x.
- alpha
-
Specifies the scalar alpha. See Scalar Arguments for more information on the value_or_pointer data type.
- x
-
Pointer to input vector x. Size of the array holding vector x must be at least (1 + (n – 1)*abs(incx)). See Matrix Storage for more details.
- incx
-
Stride of vector x.
- y
-
Pointer to input vector y. Size of the array holding vector y must be at least (1 + (n – 1)*abs(incy)). See Matrix Storage for more details.
- incy
-
Stride of vector y.
- dependencies
-
List of events to wait for before starting computation, if any. If omitted, defaults to no dependencies.
Output Parameters
- y
-
Pointer to updated vector y.
Return Values
Output event to wait on to ensure computation is complete.