Developer Reference

Contents

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
a
i
< (FLT_MAX)
1/``b`
i`
double precision
a
i
< (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
< LaTex Math image.
±0
1
±0
-LaTex Math image. <
b
< 0
+LaTex Math image.
±0
-LaTex Math image.
+LaTex Math image.
±0
b
> 0
+0
1
-LaTex Math image. <
b
< LaTex Math image.
1
±0
±0
NAN
+LaTex Math image.
±0
NAN
1
+LaTex Math image.
NAN
a
≥ 0
NAN
NAN
NAN
any value
b
NAN
0 <
a
<1
-LaTex Math image.
+LaTex Math image.
a
> 1
-LaTex Math image.
+0
0 ≤
a
< 1
+LaTex Math image.
+0
a
> 1
+LaTex Math image.
+LaTex Math image.
+LaTex Math image.
b
< +0
+0
+LaTex Math image.
b
> +0
+LaTex Math image.
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

Product and Performance Information

1

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