% EEG_RETRIEVE - Retrieve an EEG dataset from the variable

%                  containing all datasets (standard: ALLEEG).

%

% Usage: >> EEG = eeg_retrieve( ALLEEG, index );

%

% Inputs:

%   ALLEEG     - variable containing all datasets

%   index      - index of the dataset to retrieve

%

% Outputs:

%   EEG        - output dataset. The workspace variable EEG is also updated 

%   ALLEEG     - updated ALLEEG structure

%   CURRENTSET - workspace variable index of the current dataset

%

% Note: The function performs >> EEG = ALLEEG(index);

%       It also runs EEG_CHECKSET on it.

%

% Author: Arnaud Delorme, CNL / Salk Institute, 2001

%

% See also: EEG_STORE, EEGLAB

% Copyright (C) 2001 Arnaud Delorme, Salk Institute, arno@salk.edu

%

% 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

% INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

% CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

% ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

% THE POSSIBILITY OF SUCH DAMAGE.

function [EEG, ALLEEG, CURRENTSET] = eeg_retrieve( ALLEEG, CURRENTSET)

if nargin < 2

    help eeg_retrieve;

    return;

end;    

%try

    eeglab_options;

    try,   % check whether recent changes to this dataset have been saved or not

           %--------------------------------------------------------------------

           tmpsaved = { ALLEEG.saved };

           tmpsaved = tmpsaved(CURRENTSET);

    catch, tmpsaved = 'no';

    end

    if length(CURRENTSET) > 1 && option_storedisk

        [ EEG, ~ ] = eeg_checkset(ALLEEG(CURRENTSET)); % do not load data if several datasets

        if length(CURRENTSET) ~= length(ALLEEG)

            [ALLEEG, EEG, CURRENTSET] = eeg_store(ALLEEG, EEG, CURRENTSET);

        else

            ALLEEG = EEG;

        end

    else

        if CURRENTSET ~= 0

            [ EEG, ~ ] = eeg_checkset(ALLEEG(CURRENTSET), 'loaddata');

            [ALLEEG, EEG, CURRENTSET] = eeg_store(ALLEEG, EEG, CURRENTSET);

        else

            EEG = eeg_emptyset; % empty dataset

            return;

        end

    end

    % retain saved field

    % ------------------

    for index = 1:length(CURRENTSET)

        ALLEEG(CURRENTSET(index)).saved = tmpsaved{index};

        EEG(index).saved                = tmpsaved{index};

    end

%catch

%   fprintf('Warning: cannot retrieve dataset with index %d\n', CURRENTSET); 

%   return;

%end

return;