.. SPDX-FileCopyrightText: 2019-2020 Intel Corporation .. .. SPDX-License-Identifier: CC-BY-4.0 .. _onemkl_vm_ln: ln == .. container:: Computes natural logarithm of vector elements. .. container:: section .. rubric:: Syntax :class: sectiontitle Buffer API: .. code-block:: cpp namespace oneapi::mkl::vm { sycl::event ln( sycl::queue& exec_queue, std::int64_t n, sycl::buffer& a, sycl::buffer& y, oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined, oneapi::mkl::vm::error_handler errhandler = {}); } // namespace oneapi::mkl::vm USM API: .. code-block:: cpp namespace oneapi::mkl::vm { sycl::event ln( sycl::queue& exec_queue, std::int64_t n, const T *a, T* y, std::vector const & depends = {}, oneapi::mkl::vm::mode mode = oneapi::mkl::vm::mode::not_defined, oneapi::mkl::vm::error_handler errhandler = {}); } // namespace oneapi::mkl::vm ``ln`` supports the following precisions. .. list-table:: :header-rows: 1 * - T * - ``float`` * - ``double`` * - ``std::complex`` * - ``std::complex`` .. container:: section .. rubric:: Description :class: sectiontitle The ln(a)function computes natural logarithm of vector elements. .. container:: tablenoborder .. list-table:: :header-rows: 1 * - Argument - Result - Status code * - +1 - +0 -   * - a <+0 - QNAN - ``oneapi::mkl::vm::status::errdom`` * - +0 - -∞ - ``oneapi::mkl::vm::status::sing`` * - -0 - -∞ - ``oneapi::mkl::vm::status::sing`` * - -∞ - QNAN - ``oneapi::mkl::vm::status::errdom`` * - +∞ - +∞ -   * - QNAN - QNAN -   * - SNAN - QNAN -   .. container:: tablenoborder .. list-table:: :header-rows: 1 * - RE(a) i·IM(a) - -∞   - -X   - -0   - +0   - +X   - +∞   - NAN   * - +i·∞ - :math:`+\infty + i \cdot \frac{3\pi}{4}` - +∞+i·\ ``π``/2 - +∞+i·\ ``π``/2 - +∞+i·\ ``π``/2 - +∞+i·\ ``π``/2 - +∞+i·\ ``π``/4 - +∞+i·QNAN * - +i·Y - +∞-i·\ ``π`` -   -   -   -   - +∞+i·0 - QNAN+i·QNAN * - +i·0 - +∞-i·\ ``π`` -   - -∞+i·\ ``π`` - -∞-i·0 -   - +∞+i·0 - QNAN+i·QNAN * - -i·0 - +∞-i·\ ``π`` -   - -∞+i·\ ``π`` - -∞-i·0 -   - +∞-i·0 - QNAN+i·QNAN * - -i·Y - +∞-i·\ ``π`` -   -   -   -   - +∞-i·0 - QNAN+i·QNAN * - -i·∞ - :math:`+\infty - i \cdot \frac{3\pi}{4}` - +∞-i·\ ``π``/2 - +∞-i·\ ``π``/2 - +∞-i·\ ``π``/2 - +∞-i·\ ``π``/2 - +∞-i·\ ``π``/4 - +∞+i·QNAN * - +i·NAN - +∞+i·QNAN - QNAN+i·QNAN - QNAN+i·QNAN - QNAN+i·QNAN - QNAN+i·QNAN - +∞+i·QNAN - QNAN+i·QNAN .. container:: section .. rubric:: Input Parameters :class: sectiontitle Buffer API: exec_queue The queue where the routine should be executed. n Specifies the number of elements to be calculated. a The buffer ``a`` containing input vector of size ``n``. mode Overrides the global VM mode setting for this function call. See :ref:`onemkl_vm_setmode` function for possible values and their description. This is an optional parameter. The default value is ``oneapi::mkl::vm::mode::not_defined``. errhandler Sets local error handling mode for this function call. See the :ref:`onemkl_vm_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 ``a`` to the input vector of size ``n``. depends Vector of dependent events (to wait for input data to be ready). mode Overrides the global VM mode setting for this function call. See the :ref:`onemkl_vm_setmode` function for possible values and their description. This is an optional parameter. The default value is ``oneapi::mkl::vm::mode::not_defined``. errhandler Sets local error handling mode for this function call. See the :ref:`onemkl_vm_create_error_handler` function for arguments and their descriptions. This is an optional parameter. The local error handler is disabled by default. .. container:: section .. rubric:: Output Parameters :class: sectiontitle Buffer API: y The buffer ``y`` containing the output vector of size ``n``. USM API: y Pointer ``y`` to the output vector of size ``n``. return value (event) Event, signifying availability of computed output and status code(s). .. container:: section .. rubric:: Exceptions :class: sectiontitle For list of generated exceptions please refer to  :ref:`onemkl_vm_exceptions` .. container:: familylinks .. container:: parentlink **Parent topic:** :ref:`onemkl_vm_mathematical_functions`