% SUM - sum of memory mapped underlying array
%
% Author: Arnaud Delorme, SCCN, INC, UCSD, Nov. 2008

% Copyright (C) 2008 Arnaud Delorme, SCCN, INC, UCSD
%
% This file is part of EEGLAB, see http://www.eeglab.org
% for the documentation and details.
%
% Redistribution and use in source and binary forms, with or without
% modification, are permitted provided that the following conditions are met:
%
% 1. Redistributions of source code must retain the above copyright notice,
% this list of conditions and the following disclaimer.
%
% 2. Redistributions in binary form must reproduce the above copyright notice,
% this list of conditions and the following disclaimer in the documentation
% and/or other materials provided with the distribution.
%
% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
% AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
% IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
% ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
% LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
% CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
% SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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function [s] = sum(a,dim)
    
    if nargin < 2
        dim = 1;
    end
    
    %b = (:,:,:);
    if ~strcmpi(a.fileformat, 'transposed')
        s = sum(a.data.data.x, dim);
    else
        alldim = [3 1 2];
        if length(size(a)) == 3
            dim = alldim(dim);
            s = sum(a.data.data.x, dim);
            s = permute(s, [3 1 2]);
        else
            if dim == 1
                 dim = 2;
            else dim = 1;
            end
            s = sum(a.data.data.x, dim)';
        end
    end
    return;
    
    % do pnts by pnts if dim = 1
%     if dim == 1 & length(
%         
%         s = zeros(size(a,2), size(a,3));
%         for i=1:size(a,2)
%             s(i,:) = mean(a.data.data.x(:,i,:));
%         end
%     elseif dim == 1
%          s = zeros(size(a,1), size(a,1));
%         for i=1:size(a,1)
%             s(i,:) = mean(a.data.data.x(:,:,:));
%         end
%        
%         
%     s = builtin('sum', rand(10,10), dim);
    
    %if length(size(a)) > 2
    %else s = sum(a(:,:,:), dim);
    %end
