Visible to Intel only — GUID: GUID-97D8CB31-8A77-4604-A3CB-38DF8E2D74AF
Visible to Intel only — GUID: GUID-97D8CB31-8A77-4604-A3CB-38DF8E2D74AF
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.