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powr

Computes the element-wise exponentiation of vector a elements raised to the power of vector b elements, where the elements of vector a are all non-negative.

Description

The powr(a,b) function raises each element of vector a by the corresponding element of vector b. The elements of a are all nonnegative (a_i≥ 0).

Data Type	Threshold Limitations on Input Parameters
single precision	ai < (FLT_MAX)1/``b`i`
double precision	ai < (DBL_MAX)1/``b`i`

Special values and VM Error Status treatment for v?Powr function are the same as for pow, unless otherwise indicated in this table:

Argument 1	Argument 2	Result	Error Code
a < 0	any value b	NAN	status::errdom
0 < a <	±0	1
±0	- < b < 0	+
±0	-	+
±0	b > 0	+0
1	- < b <	1
±0	±0	NAN
+	±0	NAN
1	+	NAN
a≥ 0	NAN	NAN
NAN	any value b	NAN
0 < a <1	-	+
a > 1	-	+0
0 ≤a < 1	+	+0
a > 1	+	+
+	b < +0	+0
+	b > +0	+
QNAN	QNAN	QNAN	status::errdom
QNAN	SNAN	QNAN	status::errdom
SNAN	QNAN	QNAN	status::errdom
SNAN	SNAN	QNAN	status::errdom

API

Syntax

Buffer API

namespace oneapi::mkl::vm {

sycl::event powr(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 powr(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 powr(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 powr(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 = {});

}

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

examples/dpcpp/vml/source/vpowr.cpp

powx hypot