nextafter

Computes the element-wise next representable floating-point value of vector a elements in the direction of vector b elements.

Description

The nextafter(a,b) function returns a vector containing the next representable floating-point values following the first vector argument elements in the direction of the second vector argument’s corresponding elements.

Arguments/Results

Error Code

Input vector argument element is finite and the corresponding result vector element value is infinite

status::overflow

Result vector element value is subnormal or zero, and different from the corresponding input vector argument element

status::underflow

Even though underflow or overflow can occur, the returned value is independent of the current rounding direction mode.

API

Syntax

Buffer API

namespace oneapi::mkl::vm {

sycl::event nextafter(sycl::queue & exec_queue,
      std::int64_t n,
      sycl::buffer<T> & a,
      sycl::buffer<T> & b,
      sycl::buffer<T> & y,
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined,
      oneapi::mkl::vm::error_handler<T> errhandler = {});

}
namespace oneapi::mkl::vm {

sycl::event nextafter(sycl::queue & exec_queue,
      sycl::buffer<T> & a,
      oneapi::mkl::slice sa,
      sycl::buffer<T> & b,
      oneapi::mkl::slice sb,
      sycl::buffer<T> & y,
      oneapi::mkl::slice sy,
      oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined,
      oneapi::mkl::vm::error_handler<T> errhandler = {});

}

USM API

namespace oneapi::mkl::vm {

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

}
namespace oneapi::mkl::vm {

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

}

nextafter supports the following precisions and devices:

T

Devices supported

float

Host, CPU, and GPU

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 1st input vector.

sa

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

b

The buffer containing the 2nd input vector.

sb

Slice selector for b. 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.

errhandler

Sets local error handling mode for this function call. See the create_error_handler function for arguments and their descriptions. This is an optional parameter. The local error handler is disabled by default.

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 1st input vector.

sa

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

b

Pointer to the 2nd input vector.

sb

Slice selector for b. 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.

errhandler

Sets local error handling mode for this function call. See the create_error_handler function for arguments and their descriptions. This is an optional parameter. The local error handler is disabled by default.

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 nextafter can be found in the oneMKL installation directory, under:

examples/dpcpp/vml/source/vnextafter.cpp