cos
Computes the element-wise cosine of vector elements.
Description
The
cos(a)
function computes cosine of vector elements.Note that arguments
abs(a[i]) ≤ 213
and abs(a[i]) ≤ 216
for
single and double precisions, respectively, are called fast
computational path. These are trigonometric function arguments for
which VM provides the best possible performance. Avoid arguments that
do not belong to the fast computational path in the VM High Accuracy
(HA) and Low Accuracy (LA) functions. Alternatively, you can use VM
Enhanced Performance (EP) functions that are fast on the entire
function domain. However, these functions provide less accuracy.Argument | Result | VM Error Status |
---|---|---|
+0 | +1 | |
-0 | +1 | |
+ ![]() | QNAN | status::errdom |
- ![]() | QNAN | status::errdom |
QNAN | QNAN | |
SNAN | QNAN |
Specifications for special values of the complex functions are defined
according to the following formula
Cos(z) = Cosh(i*z)
.Product and Performance Information |
---|
Performance varies by use, configuration and other factors. Learn more at https://www.intel.com/PerformanceIndex. Notice revision #20201201 |
API
Syntax
Buffer API
namespace oneapi::mkl::vm {
sycl::event cos(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 cos(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 cos(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 cos(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 = {});
}
cos
supports the following precisions and devices:T | Devices supported |
---|---|
float | Host, CPU, and GPU |
double | Host, CPU, and GPU |
std::complex<float> | Host |
std::complex<double> | Host |
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 fora. See Data Types for a description of the oneMKL slice type.
- sy
- Slice selector fory. 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 ismode::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 fora. See Data Types for a description of the oneMKL slice type.
- sy
- Slice selector fory. 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 ismode::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
cos
can be found in the oneMKL
installation directory, under:examples/dpcpp/vml/source/vcos.cpp