Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / control-2.3.52 / @ss / __ctranspose__.m

diff --git a/octave_packages/control-2.3.52/@ss/__ctranspose__.m b/octave_packages/control-2.3.52/@ss/__ctranspose__.m
new file mode 100644 (file)
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+++ b/octave_packages/control-2.3.52/@ss/__ctranspose__.m
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+## Copyright (C) 2012   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 -*-
+## Conjugate transpose of SS models.
+
+## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
+## Created: May 2012
+## Version: 0.1
+
+function sys = __ctranspose__ (sys, ct)
+
+  a = sys.a;
+  b = sys.b;
+  c = sys.c;
+  d = sys.d;
+  e = sys.e;
+
+  if (ct)       # continuous-time
+    sys.a = -a.';
+    sys.b = -c.';
+    sys.c = b.';
+    sys.d = d.';
+    sys.e = e.';
+    sys.stname = repmat ({""}, rows (a), 1);
+  else          # discrete-time
+    [n, m] = size (b);
+    p = rows (c);
+    if (isempty (e))
+      e = eye (n);
+    endif
+    sys.a = blkdiag (e.', eye (p));
+    sys.b = [zeros(n, p); -eye(p)];
+    sys.c = [b.', zeros(m, p)];
+    sys.d = d.';
+    sys.e = [a.', c.'; zeros(p, n+p)];
+    sys.stname = repmat ({""}, n+p, 1);
+  endif
+
+endfunction