/usr/share/octave/packages/control-2.6.2/@ss/__sys_inverse__.m is in octave-control 2.6.2-1build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 | ## Copyright (C) 2009-2014 Lukas F. Reichlin
##
## This file is part of LTI Syncope.
##
## LTI Syncope 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.
##
## LTI Syncope 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 LTI Syncope. If not, see <http://www.gnu.org/licenses/>.
## -*- texinfo -*-
## Inversion of SS models.
## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
## Created: October 2009
## Version: 0.3
function sys = __sys_inverse__ (sys)
a = sys.a;
b = sys.b;
c = sys.c;
d = sys.d;
e = sys.e;
if (! isempty (e) || rcond (d) < eps) # dss or strictly proper ss
n = rows (a);
m = columns (b); # p = m (square system)
if (isempty (e)) # avoid testing twice?
e = eye (n);
endif
sys.a = [a, b; c, d];
sys.b = [zeros(n, m); -eye(m)];
sys.c = [zeros(m, n), eye(m)];
sys.d = zeros (m);
sys.e = [e, zeros(n, m); zeros(m, n+m)];
sys.stname = repmat ({""}, n+m, 1);
else # proper ss
bid = b / d;
sys.a = a - bid * c;
sys.b = -bid;
sys.c = d \ c;
sys.d = inv (d);
endif
endfunction
|