freemat-data 4.0-5build1 / usr / share / freemat / toolbox / array / getfield.m

% GETFIELD GETFIELD Get Field Contents
% 
% Usage
% 
% Given a structure or structure array, returns the contents of the
% specified field.  The first version is for scalar structures, and
% has the following syntax
% 
%    y = getfield(x,'fieldname')
% 
% and is equivalent to y = x.fieldname where x is a scalar (1 x 1)
% structure.  If x is not a scalar structure, then y is the 
% first value, i.e., it is equivalent to y = x(1).fieldname.  
% The second form allows you to specify a subindex into a
% structure array, and has the following syntax
% 
%     y = getfield(x, {m,n}, 'fieldname')
% 
% and is equivalent to y = x(m,n).fieldname.  You can chain multiple
% references together using this syntax.

% Copyright (c) 2002-2007 Samit Basu
% Licensed under the GPL

function y = getfield(x,varargin)
if (isempty(varargin))
  error('Need at least one additional input to getfield');
end

% Check for the simple case of a single field index
field = varargin{1};
if (length(varargin)==1 && isa(field,'char'))
  y = x.(field);
  return;
end
% Loop through the references
y = x;
for i=1:length(varargin)
  ndx = varargin{i};
  if (isa(ndx,'cell'))
    y = y(ndx{:});
  elseif (isa(ndx,'char'))
    % Dereference the field - if a contents list is returned
    % handle appropriately using a deal call
    if (length(y) == 1)
      y = y.(ndx);
    else
      tmp = cell(1,length(y));
      [tmp{:}] = deal(y.(ndx));
      y = tmp{1};
    end
  else
    error('unrecognized indexing type');
  end
end