+
−% PLUS implements addition operator for cdata objects.
+
−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
−%
+
−% DESCRIPTION: PLUS implements addition operator for two cdata objects.
+
−%
+
−% CALL:        a = d1+d2
+
−%              a = plus(d1,d2);
+
−%
+
−% <a href="matlab:utils.helper.displayMethodInfo('cdata', 'plus')">Parameters Description</a>
+
−%
+
−% VERSION:     $Id: plus.m,v 1.3 2011/04/08 08:56:34 hewitson Exp $
+
−%
+
−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
−
+
−function varargout = plus(varargin)
+
−  
+
−  % get two data objects
+
−  d1 = copy(varargin{1}, nargout);
+
−  d2 = copy(varargin{2}, nargout);
+
−  
+
−  % check units
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−  d1.yunits.simplify();
+
−  d2.yunits.simplify();
+
−  
+
−  if ~isempty(d1.yunits.strs) && ~isempty(d2.yunits.strs) && d1.yunits ~= d2.yunits
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−    error('### When adding two data objects, the yunits must be the same');
+
−  end
+
−  
+
−  % add the data
+
−  dout = applyoperator(d1,d2,'plus');
+
−  
+
−  % handle units: since both are the same, we take the first non-empty unit
+
−  if isempty(d1.yunits.strs)
+
−    dout.yunits = d2.yunits;
+
−  else
+
−    dout.yunits = d1.yunits;
+
−  end
+
−  
+
−  % handle errors
+
−  err = @(err1, err2) sqrt(err1 .^2 + err2.^2);
+
−  if ~isempty(d1.dy) || ~isempty(d2.dy)    
+
−    if isempty(d1.dy)
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−      d1.dy = zeros(size(d2.dy));
+
−    end
+
−    if isempty(d2.dy)
+
−      d2.dy = zeros(size(d1.dy));
+
−    end    
+
−    dout.dy = err(d1.dy, d2.dy);
+
−  else
+
−    dout.dy = [];
+
−  end
+
−
+
−  
+
−  % Single output
+
−  varargout{1} = dout;
+
−  
+
−end
+
−