logb¶
Computes the element-wise exponents of vector elements.
Description¶
The logb(a) function computes the exponents of the elements of the
input vector a. For each element ai of vector a,
this is the integral part of log2|ai|.
The returned value is exact and is independent of the current
rounding direction mode.
Argument |
Result |
VM Error Status |
|---|---|---|
+0 |
+ |
|
-0 |
- |
|
- |
+ |
|
+ |
+ |
|
QNAN |
QNAN |
|
SNAN |
QNAN |
API¶
Syntax¶
Buffer API
namespace oneapi::mkl::vm {
sycl::event logb(sycl::queue & exec_queue,
std::int64_t n,
sycl::buffer<T> & a,
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 logb(sycl::queue & exec_queue,
sycl::buffer<T> & a,
oneapi::mkl::slice sa,
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 logb(sycl::queue & exec_queue,
std::int64_t n,
T const * a,
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 logb(sycl::queue & exec_queue,
T const * a,
oneapi::mkl::slice sa,
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 = {});
}
logb supports the following precisions and devices:
T |
Devices supported |
|---|---|
|
Host, CPU, and GPU |
|
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 input vector.
- sa
Slice selector for
a. 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 input vector.
- sa
Slice selector for
a. 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 logb can be found in the oneMKL
installation directory, under:
examples/dpcpp/vml/source/vlogb.cpp