.. SPDX-FileCopyrightText: 2019-2020 Intel Corporation .. .. SPDX-License-Identifier: CC-BY-4.0 .. _onemkl_lapack_getri: getri ===== Computes the inverse of an LU-factored general matrix determined by :ref:`onemkl_lapack_getrf`. .. container:: section .. rubric:: Description ``getri`` supports the following precisions. .. list-table:: :header-rows: 1 * - T * - ``float`` * - ``double`` * - ``std::complex`` * - ``std::complex`` The routine computes the inverse :math:`A^{-1}` of a general matrix :math:`A`. Before calling this routine, call :ref:`onemkl_lapack_getrf` to factorize :math:`A`. getri (BUFFER Version) ---------------------- .. container:: section .. rubric:: Syntax .. code-block:: cpp namespace oneapi::mkl::lapack { void getri(sycl::queue &queue, std::int64_t n, sycl::buffer &a, std::int64_t lda, sycl::buffer &ipiv, sycl::buffer &scratchpad, std::int64_t scratchpad_size) } .. container:: section .. rubric:: Input Parameters queue The queue where the routine should be executed. n The order of the matrix :math:`A` :math:`(0 \le n)`. a The buffer ``a`` as returned by :ref:`onemkl_lapack_getrf`. Must be of size at least :math:`\text{lda} \cdot \max(1,n)`. lda The leading dimension of ``a`` :math:`(n \le \text{lda})`. ipiv The buffer as returned by :ref:`onemkl_lapack_getrf`. The dimension of ``ipiv`` must be at least :math:`\max(1, n)`. scratchpad_size Size of scratchpad memory as a number of floating point elements of type ``T``. Size should not be less than the value returned by :ref:`onemkl_lapack_getri_scratchpad_size` function. .. container:: section .. rubric:: Output Parameters a Overwritten by the :math:`n \times n` matrix :math:`A`. scratchpad Buffer holding scratchpad memory to be used by routine for storing intermediate results. getri (USM Version) ---------------------- .. container:: section .. rubric:: Syntax .. code-block:: cpp namespace oneapi::mkl::lapack { sycl::event getri(sycl::queue &queue, std::int64_t n, T *a, std::int64_t lda, std::int64_t *ipiv, T *scratchpad, std::int64_t scratchpad_size, const std::vector &events = {}) } .. container:: section .. rubric:: Input Parameters queue The queue where the routine should be executed. n The order of the matrix :math:`A` :math:`(0 \le n)`. a The array as returned by :ref:`onemkl_lapack_getrf`. Must be of size at least :math:`\text{lda} \cdot \max(1,n)`. lda The leading dimension of ``a`` :math:`(n \le \text{lda})`. ipiv The array as returned by :ref:`onemkl_lapack_getrf`. The dimension of ``ipiv`` must be at least :math:`\max(1, n)`. scratchpad_size Size of scratchpad memory as a number of floating point elements of type ``T``. Size should not be less than the value returned by :ref:`onemkl_lapack_getri_scratchpad_size` function. events List of events to wait for before starting computation. Defaults to empty list. .. container:: section .. rubric:: Output Parameters a Overwritten by the :math:`n \times n` matrix :math:`A`. scratchpad Pointer to scratchpad memory to be used by routine for storing intermediate results. .. container:: section .. rubric:: Return Values Output event to wait on to ensure computation is complete. **Parent topic:** :ref:`onemkl_lapack-linear-equation-routines`