Intel® oneAPI Math Kernel Library (oneMKL) - Data Parallel C++ Developer Reference
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Visible to Intel only — GUID: GUID-A2CB0C6A-397E-4F90-A524-A3CE5CF40C70
div
Computes the element-wise division of vector a elements by vector b elements.
Description
The div(a,b) function performs element by element division of vector a by vector b.
Argument 1 |
Argument 2 |
Result |
VM Error Status |
|---|---|---|---|
X > +0 |
+0 |
+ |
status::sing |
X > +0 |
-0 |
- |
status::sing |
X < +0 |
+0 |
- |
status::sing |
X < +0 |
-0 |
+ |
status::sing |
+0 |
+0 |
QNAN |
status::sing |
-0 |
-0 |
QNAN |
status::sing |
X > +0 |
+ |
+0 |
|
X > +0 |
- |
-0 |
|
+ |
+ |
QNAN |
|
- |
- |
QNAN |
|
QNAN |
QNAN |
QNAN |
|
SNAN |
SNAN |
QNAN |
Specifications for special values of the complex functions are defined according to the following formula
Div(x1+i*y1,x2+i*y2) = (x1+i*y1)*(x2-i*y2)/(x2*x2+y2*y2).
Overflow in a complex function occurs when x2+i*y2 is not zero, x1, x2, y1, y2 are finite numbers, but the real or imaginary part of the exact result is so large that it does not fit the target precision. In that case, the function returns 
in that part of the result, and sets the VM Error Status to status::overflow.
API
Syntax
Buffer API
namespace oneapi::mkl::vm {
sycl::event div(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 div(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 div(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 div(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 = {});
}
div supports the following precisions and devices:
T |
Devices supported |
|---|---|
float |
CPU and GPU |
double |
CPU and GPU |
std::complex<float> |
CPU and GPU |
std::complex<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 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 div can be found in the oneMKL installation directory, under:
examples/dpcpp/vml/source/vdiv.cpp