--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/m-toolbox/classes/@ssm/settlingTime.m	Wed Nov 23 19:22:13 2011 +0100
@@ -0,0 +1,105 @@
+% SETTLINGTIME retunrns 1% the settling time of the system.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+% DESCRIPTION: SETTLINGTIME retunrns 1% the settling time of the system.
+%              It is a worst scenario assumption were all variable are
+%              used.
+%
+% CALL: time = modifyTimeStep(sys,options)
+%
+% INPUTS:
+%           sys - (array of) ssm objects
+%       options - A plist or numeric value giving new timestep value (param name 'newtimestep')
+%
+% OUTPUTS:
+%           sys - (array of) ssm
+%
+% <a href="matlab:utils.helper.displayMethodInfo('ssm', 'settlingTime')">Parameters Description</a>
+%
+% VERSION: $Id: settlingTime.m,v 1.4 2011/04/08 08:56:22 hewitson Exp $
+%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+function varargout = settlingTime(varargin)
+  %% starting initial checks
+  
+  % Check if this is a call for parameters
+  if utils.helper.isinfocall(varargin{:})
+    varargout{1} = getInfo(varargin{3});
+    return
+  end
+  
+  utils.helper.msg(utils.const.msg.MNAME, ['running ', mfilename]);
+  
+  % Collect input variable names
+  in_names = cell(size(varargin));
+  for ii = 1:nargin,in_names{ii} = inputname(ii);end
+  
+  % Collect all SSMs and plists
+  sys = utils.helper.collect_objects(varargin(:), 'ssm', in_names);
+  
+  %% begin function body
+  if ~ numel(sys)==1
+    error('settlingTime take only one input ssm object')
+  end
+  
+  %% building output depending on options
+  if ~sys.isnumerical
+    error(['error in settlingTime because system "',sys.name, '" should be numerical to find settling time' ]);
+  end
+  % retriveing system infos
+  Ts = sys.timestep;
+  if Ts == 0
+    sys.modifyTimeStep(0.001)
+    Ts = 0.001;
+  end
+  A = double(sys);
+  % initializing calculus
+  tSettling = Ts;
+  k=1;
+  Xini = ones(size(A,2), 1);
+  if numel(Xini)>0
+    % iteration to observe decay
+    while   max(abs(Xini)>0.01) && Ts<1e10
+      k = k+1;
+      tSettling = tSettling + Ts;
+      Xini = A*Xini;
+      % multiply timeStep by 2 after 20 iterations
+      if k==20
+        k=1;
+        A = A*A;
+        Ts = 2*Ts;
+      end
+    end
+  else
+    tSettling = 0;
+  end
+  varargout{1} = plist('settling_time', tSettling);
+end
+
+
+%--------------------------------------------------------------------------
+% Get Info Object
+%--------------------------------------------------------------------------
+function ii = getInfo(varargin)
+  
+  if nargin == 1 && strcmpi(varargin{1}, 'None')
+    sets = {};
+    pl   = [];
+  else
+    sets = {'Default'};
+    pl   = getDefaultPlist;
+  end
+  % Build info object
+  ii = minfo(mfilename, 'ssm', 'ltpda', utils.const.categories.output, '$Id: settlingTime.m,v 1.4 2011/04/08 08:56:22 hewitson Exp $', sets, pl);
+end
+
+%--------------------------------------------------------------------------
+% Get Default Plist
+%--------------------------------------------------------------------------
+function pl = getDefaultPlist()
+  pl = plist();
+  
+  p = param({'discretize', 'The timestep used for a time-discrete system'}, 0.001 );
+  pl.append(p);
+end