--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/m-toolbox/classes/@ssm/removeEmptyBlocks.m	Wed Nov 23 19:22:13 2011 +0100
@@ -0,0 +1,124 @@
+% REMOVEEMPTYBLOCKS enables to do model simplification
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+%
+% DESCRIPTION: REMOVEEMPTYBLOCKS allows you to eliminate input/state/output variables.
+%
+% CALL:        [ssm] = REMOVEEMPTYBLOCKS(ssm, pl);
+%
+% INPUTS :
+%             ssm     - a ssm object
+%                  pl - an option plist
+%
+% OPTIONS :
+% plist with parameters 'inputs', 'states' and 'outputs' to indicate which
+% inputs, states and outputs variables are taken in account. This requires
+% proper variable naming. If a variable called appears more that once it
+% will be used once only.
+%
+% OUTPUTS:
+%           The output array are of size Nsys*Noptions
+%           sys_out -  (array of) ssm objects without the specified information
+%
+%
+% <a href="matlab:utils.helper.displayMethodInfo('ssm', 'removeEmptyBlocks')">Parameters Description</a>
+%
+% VERSION: $Id: removeEmptyBlocks.m,v 1.2 2011/07/29 13:46:09 ferran Exp $
+% 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+function varargout = removeEmptyBlocks(varargin)
+  
+  import utils.const.*
+  utils.helper.msg(msg.PROC3, 'running %s/%s', mfilename('class'), mfilename);
+  %% starting initial checks
+  
+  % Check if this is a call for parameters
+  if utils.helper.isinfocall(varargin{:})
+    varargout{1} = getInfo(varargin{3});
+    return
+  end
+  
+  % 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, ssm_invars, rest] = utils.helper.collect_objects(varargin(:), 'ssm', in_names);
+  [pl, invars2, rest]  = utils.helper.collect_objects(rest(:), 'plist');
+  if ~isempty(rest)
+    pl = combine(pl, plist(rest{:}));
+  end
+  pl = combine(pl, getDefaultPlist);
+  
+  Nsys     = numel(sys);
+  if Nsys ~= 1
+    error('### Please input (only) one SSM model');
+  end
+  
+  % Decide on a deep copy or a modify, depending on the output
+  sys = copy(sys, nargout);
+  
+  %% begin function body
+  
+  % Loop over input systems
+  for i_sys=1:Nsys
+    %% retrieving system data
+    inputSizes = sys(i_sys).inputsizes;
+    statesSizes = sys(i_sys).statesizes;
+    outputSizes = sys(i_sys).outputsizes;
+    keepInputs = inputSizes>0;
+    keepStates = statesSizes>0;
+    keepOutputs = outputSizes>0;
+    %% selecting data
+    sys.amats = sys.amats(keepStates, keepStates);
+    sys.bmats = sys.bmats(keepStates, keepInputs);
+    sys.cmats = sys.cmats(keepOutputs, keepStates);
+    sys.dmats = sys.dmats(keepOutputs, keepInputs);
+    sys.inputs = sys.inputs(keepInputs);
+    sys.states = sys.states(keepStates);
+    sys.outputs = sys.outputs(keepOutputs);
+    %% updating size fields
+    sys(i_sys).addHistory(ssm.getInfo(mfilename), pl , ssm_invars(i_sys), sys(i_sys).hist );
+    %% checking system has some inputs and outputs left
+    if sys(i_sys).Ninputs == 0
+      error('The ssm object has no inputs, which is not allowed!')
+    elseif sys(i_sys).Noutputs == 0
+      error('The ssm object has no outputs, which is not allowed!')
+    end
+  end
+  
+  if nargout == numel(sys)
+    for ii = 1:numel(sys)
+      varargout{ii} = sys(ii);
+    end
+  else
+    varargout{1} = sys;
+  end
+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.op, '$Id: removeEmptyBlocks.m,v 1.2 2011/07/29 13:46:09 ferran Exp $', sets, pl);
+end
+
+%--------------------------------------------------------------------------
+% Get Default Plist
+%--------------------------------------------------------------------------
+function pl = getDefaultPlist()
+  pl = plist();
+  
+end
+