Visible to Intel only — GUID: GUID-0C894224-CAB8-4960-9E72-2AC87F6A4A1A
Visible to Intel only — GUID: GUID-0C894224-CAB8-4960-9E72-2AC87F6A4A1A
lgamma
Computes the element-wise natural logarithm of the absolute value of the gamma function of vector elements.
Description
The lgamma(a) function computes the natural logarithm of the absolute value of gamma function for elements of the input vector a and writes them to the output vector y. Precision overflow thresholds for the lgamma function are beyond the scope of this document. If the result does not meet the target precision, the function sets the VM Error Status to status::overflow.
Argument |
Result |
Error Code |
---|---|---|
+1 |
+0 |
|
+2 |
+0 |
|
+0 |
+ |
status::sing |
-0 |
+ |
status::sing |
negative integer |
+ |
status::sing |
- |
+ |
|
+ |
+ |
|
a > overflow |
+ |
status::overflow |
QNAN |
QNAN |
|
SNAN |
QNAN |
API
Syntax
Buffer API
namespace oneapi::mkl::vm { sycl::event lgamma(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 lgamma(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 lgamma(sycl::queue & exec_queue, std::int64_t n, T const * a, 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 lgamma(sycl::queue & exec_queue, T const * a, oneapi::mkl::slice sa, 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 = {}); }
lgamma supports the following precisions and devices:
T |
Devices supported |
---|---|
float |
CPU |
double |
CPU |
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 lgamma can be found in the oneMKL installation directory, under:
examples/dpcpp/vml/source/vlgamma.cpp