Contents

arg

Computes the argument of vector elements in [-pi, pi].

Description

The arg(a) function computes argument of vector elements.

See Special Value Notations for the conventions used in the table below.

RE(a) i·IM(a)

-\infty

-X

-0

+0

+X

+\infty

NAN

+i·\infty

+3·\pi /4

+\pi/2

+\pi/2

+\pi/2

+\pi/2

+\pi/4

NAN

+i·Y

+\pi

+\pi/2

+\pi/2

+0

NAN

+i·0

+\pi

+\pi

+\pi

+0

+0

+0

NAN

-i·0

-\pi

-\pi

-\pi

-0

-0

-0

NAN

-i·Y

-\pi

-\pi/2

-\pi/2

-0

NAN

-i·\infty

-3·\pi/4

-\pi/2

-\pi/2

-\pi/2

-\pi/2

-\pi/4

NAN

+i·NAN

NAN

NAN

NAN

NAN

NAN

NAN

NAN

Note

arg(a)=atan2(IM(a),RE(a))

The arg function does not generate any errors.

API

Syntax

Buffer API

namespace oneapi::mkl::vm {

sycl::event arg(sycl::queue & exec_queue,
      std::int64_t n,
      sycl::buffer<T> & a,
      sycl::buffer<T> & y,
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined);

}

namespace oneapi::mkl::vm {

sycl::event arg(sycl::queue & exec_queue,
      sycl::buffer<T> & a,
      oneapi::mkl::slice sa,
      sycl::buffer<T> & y,
      oneapi::mkl::slice sy,
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined);

}

USM API

namespace oneapi::mkl::vm {

sycl::event arg(sycl::queue & exec_queue,
      std::int64_t n,
      T const * a,
      T * y,
      std::vector<cl::sycl::event> const & depends = {},
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined);

}

namespace oneapi::mkl::vm {

sycl::event arg(sycl::queue & exec_queue,
      T const * a,
      oneapi::mkl::slice sa,
      T * y,
      oneapi::mkl::slice sy,
      std::vector<cl::sycl::event> const & depends = {},
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined);

}

arg supports the following precisions and devices:

T

Devices supported

std::complex<float>

Host, CPU, and GPU

std::complex<double>

Host, CPU, and GPU

Input Parameters

Buffer API

exec_queue

The queue where the routine should be executed.

n

Specifies the number of elements to be calculated.

a

The buffer containing the input vector.

sa

Slice selector for a. See Data Types for a description of the oneMKL slice type.

sy

Slice selector for y. See Data Types for a description of the oneMKL slice type.

mode

Overrides the global VM mode setting for this function call. See set_mode function for possible values and their description. This is an optional parameter. The default value is mode::not_defined.

USM API

exec_queue

The queue where the routine should be executed.

n

Specifies the number of elements to be calculated.

a

Pointer to the input vector.

sa

Slice selector for a. See Data Types for a description of the oneMKL slice type.

sy

Slice selector for y. See Data Types for a description of the oneMKL slice type.

depends

Vector of dependent events (to wait for input data to be ready). This is an optional parameter. The default is an empty vector.

mode

Overrides the global VM mode setting for this function call. See the set_mode function for possible values and their description. This is an optional parameter. The default value is mode::not_defined.

Output Parameters

Buffer API

y

The buffer containing the output vector.

return value (event)

Computation end event.

USM API

y

Pointer to the output vector.

return value (event)

Computation end event.

Examples

An example of how to use arg can be found in the oneMKL installation directory, under:

examples/dpcpp/vml/source/varg.cpp
abs linearfrac