dot#

Computes the dot product of two real vectors.

Description

The dot routines perform a dot product between two vectors:

\[result = \sum_{i=1}^{n}X_iY_i\]

dot supports the following precisions for data.

T

T_res

half

half

bfloat16

bfloat16

float

float

double

double

float

double

T	T_res
`half`	`half`
`bfloat16`	`bfloat16`
`float`	`float`
`double`	`double`
`float`	`double`

Note

For the mixed precision version (inputs are float while result is double), the dot product is computed with double precision.

dot (Buffer Version)#

Syntax

namespace oneapi::mkl::blas::column_major {
    void dot(sycl::queue &queue,
             std::int64_t n,
             sycl::buffer<T,1> &x,
             std::int64_t incx,
             sycl::buffer<T,1> &y,
             std::int64_t incy,
             sycl::buffer<T_res,1> &result)
}

namespace oneapi::mkl::blas::row_major {
    void dot(sycl::queue &queue,
             std::int64_t n,
             sycl::buffer<T,1> &x,
             std::int64_t incx,
             sycl::buffer<T,1> &y,
             std::int64_t incy,
             sycl::buffer<T_res,1> &result)
}

Input Parameters

queue: The queue where the routine should be executed.
n: Number of elements in vectors x and y.
x: Buffer holding input vector x. The buffer must be of size at least (1 + (n – 1)*abs(incx)). See Matrix Storage for more details.
incx: Stride of vector x.
y: Buffer holding input vector y. The buffer must be of size at least (1 + (n – 1)*abs(incy)). See Matrix Storage for more details.
incy: Stride of vector y.

Output Parameters

result: Buffer where the result (a scalar) will be stored.

Throws

This routine shall throw the following exceptions if the associated condition is detected. An implementation may throw additional implementation-specific exception(s) in case of error conditions not covered here.

oneapi::mkl::invalid_argument

oneapi::mkl::unsupported_device

oneapi::mkl::host_bad_alloc

oneapi::mkl::device_bad_alloc

oneapi::mkl::unimplemented

dot (USM Version)#

Syntax

namespace oneapi::mkl::blas::column_major {
    sycl::event dot(sycl::queue &queue,
                    std::int64_t n,
                    const T *x,
                    std::int64_t incx,
                    const T *y,
                    std::int64_t incy,
                    T_res *result,
                    const std::vector<sycl::event> &dependencies = {})
}

namespace oneapi::mkl::blas::row_major {
    sycl::event dot(sycl::queue &queue,
                    std::int64_t n,
                    const T *x,
                    std::int64_t incx,
                    const T *y,
                    std::int64_t incy,
                    T_res *result,
                    const std::vector<sycl::event> &dependencies = {})
}

Input Parameters

queue: The queue where the routine should be executed.
n: Number of elements in vectors x and y.
x: Pointer to the input vector x. The array holding the vector x must be of size at least (1 + (n – 1)*abs(incx)). See Matrix Storage for more details.
incx: Stride of vector x.
y: Pointer to the input vector y. The array holding the vector y must be of size 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.