asum

Computes the sum of magnitudes of the vector elements.

Description

The asum routine computes the sum of the magnitudes of elements of a real vector, or the sum of magnitudes of the real and imaginary parts of elements of a complex vector:

\mathrm{result} = \sum_{i=1}^n
\left( |\mathrm{Re} (X_i)| + |\mathrm{Im}(X_i)| \right)

where x is a vector with n elements.

API

Syntax

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

asum supports the following precisions and devices.

T

T_res

Devices Supported

float

float

Host, CPU, and GPU

double

double

Host, CPU, and GPU

std::complex<float>

float

Host, CPU, and GPU

std::complex<double>

double

Host, CPU, and GPU

Input Parameters

exec_queue

The queue where the routine should be executed.

n

Number of elements in vector x.

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.

Output Parameters

result

Buffer where the scalar result is stored (the sum of magnitudes of the real and imaginary parts of all elements of the vector).