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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 (ai≥ 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 |
- |
+ |
|
±0 |
- |
+ |
|
±0 |
b > 0 |
+0 |
|
1 |
- |
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<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<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 |
CPU and GPU |
double |
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