Mercurial > octave
view libinterp/corefcn/hess.cc @ 30923:7ad60a258a2b
Allow "econ" argument to qr() function (bug #62277).
* qr.cc (Fqr): Add documentation for "econ" input argument.
Add input decoding for string "econ". Change error message
for unrecognized input to bound it with double quote characters.
Update functional and input validation BIST tests.
author | Arun Giridhar <arungiridhar@gmail.com> |
---|---|
date | Sat, 09 Apr 2022 14:52:25 -0700 |
parents | 796f54d4ddbf |
children | e88a07dec498 |
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//////////////////////////////////////////////////////////////////////// // // Copyright (C) 1996-2022 The Octave Project Developers // // See the file COPYRIGHT.md in the top-level directory of this // distribution or <https://octave.org/copyright/>. // // This file is part of Octave. // // Octave is free software: you can redistribute it and/or modify it // under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // Octave is distributed in the hope that it will be useful, but // WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with Octave; see the file COPYING. If not, see // <https://www.gnu.org/licenses/>. // //////////////////////////////////////////////////////////////////////// #if defined (HAVE_CONFIG_H) # include "config.h" #endif #include "hess.h" #include "defun.h" #include "error.h" #include "errwarn.h" #include "ovl.h" OCTAVE_NAMESPACE_BEGIN DEFUN (hess, args, nargout, doc: /* -*- texinfo -*- @deftypefn {} {@var{H} =} hess (@var{A}) @deftypefnx {} {[@var{P}, @var{H}] =} hess (@var{A}) @cindex Hessenberg decomposition Compute the Hessenberg decomposition of the matrix @var{A}. The Hessenberg decomposition is @tex $$ A = PHP^T $$ where $P$ is a square unitary matrix ($P^TP = I$), and $H$ is upper Hessenberg ($H_{i,j} = 0, \forall i > j+1$). @end tex @ifnottex @code{@var{P} * @var{H} * @var{P}' = @var{A}} where @var{P} is a square unitary matrix (@code{@var{P}' * @var{P} = I}, using complex-conjugate transposition) and @var{H} is upper Hessenberg (@code{@var{H}(i, j) = 0 forall i > j+1)}. @end ifnottex The Hessenberg decomposition is usually used as the first step in an eigenvalue computation, but has other applications as well (see @nospell{Golub, Nash, and Van Loan}, IEEE Transactions on Automatic Control, 1979). @seealso{eig, chol, lu, qr, qz, schur, svd} @end deftypefn */) { if (args.length () != 1) print_usage (); octave_value arg = args(0); if (arg.isempty ()) return octave_value_list (2, Matrix ()); if (arg.rows () != arg.columns ()) err_square_matrix_required ("hess", "A"); octave_value_list retval; if (arg.is_single_type ()) { if (arg.isreal ()) { FloatMatrix tmp = arg.float_matrix_value (); math::hess<FloatMatrix> result (tmp); if (nargout <= 1) retval = ovl (result.hess_matrix ()); else retval = ovl (result.unitary_hess_matrix (), result.hess_matrix ()); } else if (arg.iscomplex ()) { FloatComplexMatrix ctmp = arg.float_complex_matrix_value (); math::hess<FloatComplexMatrix> result (ctmp); if (nargout <= 1) retval = ovl (result.hess_matrix ()); else retval = ovl (result.unitary_hess_matrix (), result.hess_matrix ()); } } else { if (arg.isreal ()) { Matrix tmp = arg.matrix_value (); math::hess<Matrix> result (tmp); if (nargout <= 1) retval = ovl (result.hess_matrix ()); else retval = ovl (result.unitary_hess_matrix (), result.hess_matrix ()); } else if (arg.iscomplex ()) { ComplexMatrix ctmp = arg.complex_matrix_value (); math::hess<ComplexMatrix> result (ctmp); if (nargout <= 1) retval = ovl (result.hess_matrix ()); else retval = ovl (result.unitary_hess_matrix (), result.hess_matrix ()); } else err_wrong_type_arg ("hess", arg); } return retval; } /* %!test %! a = [1, 2, 3; 5, 4, 6; 8, 7, 9]; %! [p, h] = hess (a); %! assert (p * h * p', a, sqrt (eps)); %!test %! a = single ([1, 2, 3; 5, 4, 6; 8, 7, 9]); %! [p, h] = hess (a); %! assert (p * h * p', a, sqrt (eps ("single"))); %!error hess () %!error hess ([1, 2; 3, 4], 2) %!error <must be a square matrix> hess ([1, 2; 3, 4; 5, 6]) */ OCTAVE_NAMESPACE_END