Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / control-2.3.52 / isdetectable.m

diff --git a/octave_packages/control-2.3.52/isdetectable.m b/octave_packages/control-2.3.52/isdetectable.m
new file mode 100644 (file)
index 0000000..727b8ec
--- /dev/null
+++ b/octave_packages/control-2.3.52/isdetectable.m
@@ -0,0 +1,87 @@
+## Copyright (C) 2009, 2010   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 -*-
+## @deftypefn {Function File} {@var{bool} =} isdetectable (@var{sys})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{sys}, @var{tol})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{e})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{[]}, @var{tol})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{e}, @var{tol})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{[]}, @var{[]}, @var{dflg})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{e}, @var{[]}, @var{dflg})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{[]}, @var{tol}, @var{dflg})
+## @deftypefnx {Function File} {@var{bool} =} isdetectable (@var{a}, @var{c}, @var{e}, @var{tol}, @var{dflg})
+## Logical test for system detectability.
+## All unstable modes must be observable or all unobservable states must be stable.
+##
+## @strong{Inputs}
+## @table @var
+## @item sys
+## LTI system.
+## @item a
+## State transition matrix.
+## @item c
+## Measurement matrix.
+## @item e
+## Descriptor matrix.
+## If @var{e} is empty @code{[]} or not specified, an identity matrix is assumed.
+## @item tol
+## Optional tolerance for stability.  Default value is 0.
+## @item dflg = 0
+## Matrices (@var{a}, @var{c}) are part of a continuous-time system.  Default Value.
+## @item dflg = 1
+## Matrices (@var{a}, @var{c}) are part of a discrete-time system.
+## @end table
+##
+## @strong{Outputs}
+## @table @var
+## @item bool = 0
+## System is not detectable.
+## @item bool = 1
+## System is detectable.
+## @end table
+##
+##
+## @strong{Algorithm}@*
+## Uses SLICOT AB01OD and TG01HD by courtesy of
+## @uref{http://www.slicot.org, NICONET e.V.}
+## See @command{isstabilizable} for description of computational method.
+## @seealso{isstabilizable, isstable, isctrb, isobsv}
+## @end deftypefn
+
+## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
+## Created: October 2009
+## Version: 0.3
+
+function bool = isdetectable (a, c = [], e = [], tol = [], dflg = 0)
+
+  if (nargin == 0)
+    print_usage ();
+  elseif (isa (a, "lti"))                              # isdetectable (sys), isdetectable (sys, tol)
+    if (nargin > 2)
+      print_usage ();
+    endif
+    bool = isstabilizable (a.', c);                    # transpose is overloaded
+  elseif (nargin < 2 || nargin > 5)
+    print_usage ();
+  else                                                 # isdetectable (a, c, ...)
+    bool = isstabilizable (a.', c.', e.', tol, dflg);  # arguments checked inside
+  endif
+
+endfunction
+