Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / control-2.3.52 / @tf / __sys_group__.m

diff --git a/octave_packages/control-2.3.52/@tf/__sys_group__.m b/octave_packages/control-2.3.52/@tf/__sys_group__.m
new file mode 100644 (file)
index 0000000..69802a5
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+++ b/octave_packages/control-2.3.52/@tf/__sys_group__.m
@@ -0,0 +1,68 @@
+## Copyright (C) 2009, 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 -*-
+## Block diagonal concatenation of two TF models.
+## This file is part of the Model Abstraction Layer.
+## For internal use only.
+
+## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
+## Created: September 2009
+## Version: 0.2
+
+function retsys = __sys_group__ (sys1, sys2)
+
+  if (! isa (sys1, "tf"))
+    sys1 = tf (sys1);
+  endif
+
+  if (! isa (sys2, "tf"))
+    sys2 = tf (sys2);
+  endif
+
+  retsys = tf ();
+
+  retsys.lti = __lti_group__ (sys1.lti, sys2.lti);
+
+  [p1, m1] = size (sys1);
+  [p2, m2] = size (sys2);
+
+  empty12 = tfpolyzeros (p1, m2);
+  empty21 = tfpolyzeros (p2, m1);
+
+  retsys.num = [sys1.num, empty12 ;
+                empty21,  sys2.num];
+
+  empty12 = tfpolyones (p1, m2);
+  empty21 = tfpolyones (p2, m1);
+
+  retsys.den = [sys1.den, empty12 ;
+                empty21,  sys2.den];
+
+  if (sys1.tfvar == sys2.tfvar)
+    retsys.tfvar = sys1.tfvar;
+  elseif (sys1.tfvar == "x")
+    retsys.tfvar = sys2.tfvar;
+  else
+    retsys.tfvar = sys1.tfvar;
+  endif
+
+  if (sys1.inv || sys2.inv)
+    retsys.inv = true;
+  endif
+
+endfunction