Intel® oneAPI Math Kernel Library (oneMKL) - Data Parallel C++ Developer Reference

Developer Reference

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)
-LaTex Math image.
-X
-0
+0
+X
+LaTex Math image.
NAN
+i·LaTex Math image.
+3·LaTex Math image.
+LaTex Math image./2
+LaTex Math image./2
+LaTex Math image./2
+LaTex Math image./2
+LaTex Math image./4
NAN
+i·Y
+LaTex Math image.
+LaTex Math image./2
+LaTex Math image./2
+0
NAN
+i·0
+LaTex Math image.
+LaTex Math image.
+LaTex Math image.
+0
+0
+0
NAN
-i·0
-LaTex Math image.
-LaTex Math image.
-LaTex Math image.
-0
-0
-0
NAN
-i·Y
-LaTex Math image.
-LaTex Math image./2
-LaTex Math image./2
-0
NAN
-i·LaTex Math image.
-3·LaTex Math image./4
-LaTex Math image./2
-LaTex Math image./2
-LaTex Math image./2
-LaTex Math image./2
-LaTex Math image./4
NAN
+i·NAN
NAN
NAN
NAN
NAN
NAN
NAN
NAN
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

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.