+
−% INV evaluates the inverse for matrix object.
+
−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
−%
+
−% DESCRIPTION: INV evaluates the inverse for matrix objects.
+
−%
+
−% CALL:        obj = inv(mat)
+
−%              obj = mat.inv()
+
−%
+
−% <a href="matlab:utils.helper.displayMethodInfo('matrix', 'inv')">Parameters Description</a>
+
−%
+
−% VERSION:     $Id: inv.m,v 1.10 2011/04/08 08:56:31 hewitson Exp $
+
−%
+
−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
−
+
−function varargout = inv(varargin)
+
−  
+
−  % Check if this is a call for parameters
+
−  if utils.helper.isinfocall(varargin{:})
+
−    varargout{1} = getInfo(varargin{3});
+
−    return
+
−  end
+
−  
+
−  % Check if the method was called by another method
+
−  callerIsMethod = utils.helper.callerIsMethod;
+
−  
+
−  % Collect input variable names
+
−  in_names = cell(size(varargin));
+
−  for ii = 1:nargin,in_names{ii} = inputname(ii);end
+
−  
+
−  % Collect all matrices and plists
+
−  [as, matrix_invars, rest] = utils.helper.collect_objects(varargin(:), 'matrix', in_names);
+
−  [pl, pl_invars, rest]     = utils.helper.collect_objects(varargin(:), 'plist', in_names);
+
−  
+
−  % Decide on a deep copy or a modify
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−  bs = copy(as, nargout);
+
−  
+
−  % Combine input plists and default plist
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−  usepl = parse(pl, getDefaultPlist());
+
−  
+
−  % do dimension check
+
−  [rw,cl] = size(bs.objs);
+
−  if rw ~= cl
+
−    error('### Matrix must be square');
+
−  end
+
−  
+
−  % get the determinant
+
−  DA = det(bs);
+
−  
+
−  % build cofactor matrix
+
−  C = copy(bs,1);
+
−  for ii = 1:rw % raw index
+
−    for jj = 1:cl % column index
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−      % ij Minor of A
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−      MA = copy(bs,1);
+
−      MA.objs(ii,:) = [];
+
−      MA.objs(:,jj) = [];
+
−      % cofactor
+
−      C.objs(ii,jj) = det(MA).*((-1)^(ii+jj));
+
−    end
+
−  end
+
−  % get the transpose of cofactors matrix
+
−  CT = transpose(C);
+
−  % do inverse
+
−  bs = CT./matrix(DA);
+
−  
+
−  if ~callerIsMethod
+
−    % set name
+
−    bs.setName(sprintf('inv(%s)', in_names{1}));
+
−    
+
−    % Add history
+
−    bs.addHistory(getInfo('None'), usepl, [matrix_invars(:)], [as(:).hist]);
+
−  end
+
−  
+
−  varargout{1} = bs;
+
−  
+
−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, 'matrix', 'ltpda', utils.const.categories.op, '$Id: inv.m,v 1.10 2011/04/08 08:56:31 hewitson Exp $', sets, pl);
+
−end
+
−
+
−%--------------------------------------------------------------------------
+
−% Get Default Plist
+
−%--------------------------------------------------------------------------
+
−
+
−function plout = getDefaultPlist()
+
−  persistent pl;
+
−  if ~exist('pl', 'var') || isempty(pl)
+
−    pl = buildplist();
+
−  end
+
−  plout = pl;
+
−end
+
−
+
−function pl = buildplist()
+
−  pl = plist.EMPTY_PLIST;
+
−end
+
−