Mercurial > octave
view libinterp/corefcn/sylvester.cc @ 21662:5b9868c2e212
maint: Octave coding convention cleanups.
* Figure.cc, QtHandlesUtils.cc, files-dock-widget.cc, find-files-dialog.cc,
debug.cc, ls-hdf5.h, oct-fstrm.h, oct-iostrm.h, oct-stdstrm.h, oct-stream.h,
pr-output.cc, sysdep.cc, zfstream.h, pt-cbinop.cc, f77-fcn.h, DASPK.cc,
DASSL.cc, cmd-hist.cc, glob-match.h:
Cuddle angle bracket '<' next to C++ cast operator.
Space between variable reference and variable name (int& a).
Space between bitwise operators and their operands (A & B).
Create typedef tree_expression_ptr_t to avoid "tree_expression *&a"
which is unclear.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 02 May 2016 11:13:50 -0700 |
parents | 40de9f8f23a6 |
children | aba2e6293dd8 |
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/* Copyright (C) 1996-2015 John W. Eaton 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 <http://www.gnu.org/licenses/>. */ // Author: A. S. Hodel <scotte@eng.auburn.edu> #ifdef HAVE_CONFIG_H # include "config.h" #endif #include "defun.h" #include "error.h" #include "errwarn.h" #include "ovl.h" #include "utils.h" DEFUN (sylvester, args, , "-*- texinfo -*-\n\ @deftypefn {} {@var{X} =} syl (@var{A}, @var{B}, @var{C})\n\ Solve the Sylvester equation\n\ @tex\n\ $$\n\ A X + X B = C\n\ $$\n\ @end tex\n\ @ifnottex\n\ \n\ @example\n\ A X + X B = C\n\ @end example\n\ \n\ @end ifnottex\n\ using standard @sc{lapack} subroutines.\n\ \n\ For example:\n\ \n\ @example\n\ @group\n\ sylvester ([1, 2; 3, 4], [5, 6; 7, 8], [9, 10; 11, 12])\n\ @result{} [ 0.50000, 0.66667; 0.66667, 0.50000 ]\n\ @end group\n\ @end example\n\ @end deftypefn") { if (args.length () != 3) print_usage (); octave_value retval; octave_value arg_a = args(0); octave_value arg_b = args(1); octave_value arg_c = args(2); octave_idx_type a_nr = arg_a.rows (); octave_idx_type a_nc = arg_a.columns (); octave_idx_type b_nr = arg_b.rows (); octave_idx_type b_nc = arg_b.columns (); octave_idx_type c_nr = arg_c.rows (); octave_idx_type c_nc = arg_c.columns (); int arg_a_is_empty = empty_arg ("sylvester", a_nr, a_nc); int arg_b_is_empty = empty_arg ("sylvester", b_nr, b_nc); int arg_c_is_empty = empty_arg ("sylvester", c_nr, c_nc); bool isfloat = arg_a.is_single_type () || arg_b.is_single_type () || arg_c.is_single_type (); if (arg_a_is_empty > 0 && arg_b_is_empty > 0 && arg_c_is_empty > 0) if (isfloat) return ovl (FloatMatrix ()); else return ovl (Matrix ()); else if (arg_a_is_empty || arg_b_is_empty || arg_c_is_empty) return retval; // Arguments are not empty, so check for correct dimensions. if (a_nr != a_nc) err_square_matrix_required ("sylvester", "A"); if (b_nr != b_nc) err_square_matrix_required ("sylvester", "B"); if (a_nr != c_nr || b_nr != c_nc) err_nonconformant (); if (isfloat) { if (arg_a.is_complex_type () || arg_b.is_complex_type () || arg_c.is_complex_type ()) { // Do everything in complex arithmetic; FloatComplexMatrix ca = arg_a.float_complex_matrix_value (); FloatComplexMatrix cb = arg_b.float_complex_matrix_value (); FloatComplexMatrix cc = arg_c.float_complex_matrix_value (); retval = Sylvester (ca, cb, cc); } else { // Do everything in real arithmetic. FloatMatrix ca = arg_a.float_matrix_value (); FloatMatrix cb = arg_b.float_matrix_value (); FloatMatrix cc = arg_c.float_matrix_value (); retval = Sylvester (ca, cb, cc); } } else { if (arg_a.is_complex_type () || arg_b.is_complex_type () || arg_c.is_complex_type ()) { // Do everything in complex arithmetic; ComplexMatrix ca = arg_a.complex_matrix_value (); ComplexMatrix cb = arg_b.complex_matrix_value (); ComplexMatrix cc = arg_c.complex_matrix_value (); retval = Sylvester (ca, cb, cc); } else { // Do everything in real arithmetic. Matrix ca = arg_a.matrix_value (); Matrix cb = arg_b.matrix_value (); Matrix cc = arg_c.matrix_value (); retval = Sylvester (ca, cb, cc); } } return retval; } /* %!assert (sylvester ([1, 2; 3, 4], [5, 6; 7, 8], [9, 10; 11, 12]), [1/2, 2/3; 2/3, 1/2], sqrt (eps)) %!assert (sylvester (single ([1, 2; 3, 4]), single ([5, 6; 7, 8]), single ([9, 10; 11, 12])), single ([1/2, 2/3; 2/3, 1/2]), sqrt (eps ("single"))) %% Test input validation %!error sylvester () %!error sylvester (1) %!error sylvester (1,2) %!error sylvester (1, 2, 3, 4) %!error <A must be a square matrix> sylvester (ones (2,3), ones (2,2), ones (2,2)) %!error <B must be a square matrix> sylvester (ones (2,2), ones (2,3), ones (2,2)) %!error <nonconformant matrices> sylvester (ones (2,2), ones (2,2), ones (3,3)) */