tlapack/getri__uili_8hpp_source.html

//

// Copyright (c) 2025, University of Colorado Denver. All rights reserved.

//

// This file is part of <T>LAPACK.

// <T>LAPACK is free software: you can redistribute it and/or modify it under

// the terms of the BSD 3-Clause license. See the accompanying LICENSE file.


#ifndef TLAPACK_getri_uili_HH

#define TLAPACK_getri_uili_HH


#include "tlapack/base/utils.hpp"

#include "tlapack/blas/gemm.hpp"

#include "tlapack/lapack/trtri_recursive.hpp"

#include "tlapack/lapack/ul_mult.hpp"


namespace tlapack {


template <TLAPACK_MATRIX matrix_t>


int getri_uili(matrix_t& A)

{

    // check arguments

    tlapack_check(nrows(A) == ncols(A));


    // Invert the upper part of A; U

    int info = trtri_recursive(UPPER_TRIANGLE, NON_UNIT_DIAG, A);

    if (info != 0) return info;


    // Invert the lower part of A; L which has 1 on the diagonal

    trtri_recursive(LOWER_TRIANGLE, UNIT_DIAG, A);


    // multiply U^{-1} and L^{-1} in place using ul_mult

    ul_mult(A);


    return 0;


}  // getri_uili


}  // namespace tlapack


#endif  // TLAPACK_getri_uili_HH

tlapack::LOWER_TRIANGLE
constexpr internal::LowerTriangle LOWER_TRIANGLE
Lower Triangle access.
Definition types.hpp:188

tlapack::UPPER_TRIANGLE
constexpr internal::UpperTriangle UPPER_TRIANGLE
Upper Triangle access.
Definition types.hpp:186

tlapack::UNIT_DIAG
constexpr internal::UnitDiagonal UNIT_DIAG
The main diagonal is assumed to consist of 1's.
Definition types.hpp:222

tlapack::NON_UNIT_DIAG
constexpr internal::NonUnitDiagonal NON_UNIT_DIAG
The main diagonal is not assumed to consist of 1's.
Definition types.hpp:220

utils.hpp

gemm.hpp

tlapack::ul_mult
int ul_mult(matrix_t &A)
ul_mult computes the matrix product of an upper triangular matrix U and a lower triangular unital mat...
Definition ul_mult.hpp:34

tlapack::getri_uili
int getri_uili(matrix_t &A)
getri_uili calculates the inverse of a general n-by-n matrix A
Definition getri_uili.hpp:39

tlapack::trtri_recursive
int trtri_recursive(uplo_t uplo, Diag diag, matrix_t &C, const EcOpts &opts={})
TRTRI computes the inverse of a triangular matrix in-place Input is a triangular matrix,...
Definition trtri_recursive.hpp:48

tlapack_check
#define tlapack_check(cond)
Throw an error if cond is false.
Definition exceptionHandling.hpp:98

tlapack::real_type
typename traits::real_type_traits< Types..., int >::type real_type
The common real type of the list of types.
Definition scalar_type_traits.hpp:113

trtri_recursive.hpp

ul_mult.hpp