getkeyval.m

% GETKEYVAL - get variable value from a 'key', 'val' sequence string.
%
% Usage:
%   >> val = getkeyval( keyvalstr, varname, mode, defaultval);   
%     
% Inputs:            
%   keyvalstr  - string containing 'key', 'val' arguments
%   varname    - string for the name of the variable or index
%                of the value to retrieve (assuming arguments are
%                separated by comas).
%   mode       - if the value extracted is an integer array, the
%                'mode' variable can contain a subset of indexes to return.
%                If mode is 'present', then either 0 or 1 is returned
%                depending on whether the variable is present.
%   defaultval - default value if the variable is not found
%
% Outputs:
%   val  - a value for the variable
%
% Note: this function is helpful for finding arguments in string commands
%       stored in command history.
%
% Author: Arnaud Delorme, CNL / Salk Institute, 29 July 2002
%
% See also: GETHELPVAR

% Copyright (C) 2002 arno@salk.edu, Arnaud Delorme, CNL / Salk Institute
%
% 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 txt = getkeyval(lastcom, var, mode, default)
    % mode can be present for 0 and 1 if the variable is present
	if nargin < 1
        help getkeyval;
        return;
    end
    if nargin < 4
		default = '';
	end
	if isempty(lastcom)
		txt = default; return;
	end
	if nargin < 3
		mode = '';
	end
	if ischar(mode) && strcmp(mode, 'present')
		if ~isempty(findstr(var, lastcom))
			txt = 1; return;
		else
			txt = 0; return;
		end
	end
	if isnumeric(var)
		comas = findstr(lastcom, ',');
		if length(comas) >= var
			txt = lastcom(comas(var-1)+1:comas(var)-1);
            tmpval = eval( txt );
            if isempty(tmpval), txt = '';
            else txt = vararg2str( tmpval );
            end
            return;
            
% 			txt = deblank(txt(end:-1:1));
% 			txt = deblank(txt(end:-1:1));
%             
% 			if ~isempty(txt) & txt(end) == '}', txt = txt(2:end-1); end
% 			if ~isempty(txt)
% 				txt = deblank(txt(end:-1:1));
% 				txt = deblank(txt(end:-1:1));
% 			end
% 			if ~isempty(txt) & txt(end) == ']', txt = txt(2:end-1); end
% 			if ~isempty(txt)
% 				txt = deblank(txt(end:-1:1));
% 				txt = deblank(txt(end:-1:1));
% 			end
% 			if ~isempty(txt) & txt(end) == '''', txt = txt(2:end-1); end
		else
			txt = default;
		end
		%fprintf('%s:%s\n', var, txt);		
		return;
	else
		comas  = findstr(lastcom, ','); % finding all comas
		comas  = [ comas  findstr(lastcom, ');') ]; % and end of lines
		varloc = findstr(lastcom, var);
		if ~isempty(varloc)
			% finding comas surrounding 'val' var in 'key', 'val' sequence
			comas = comas(find(comas >varloc(end)));
			txt = lastcom(comas(1)+1:comas(2)-1); 
			txt = deblank(txt(end:-1:1));
			txt = deblank(txt(end:-1:1));
			if strcmp(mode, 'full')
				parent = findstr(lastcom, '}');
				if ~isempty(parent)
					comas = comas(find(comas >parent(1)));
					txt = lastcom(comas(1)+1:comas(2)-1);
				end
				txt = [ '''' var ''', ' txt ];	
			elseif isnumeric(mode)
				txt = str2num(txt);
				if ~isempty(mode)
					if length(txt) >= max(mode)
						if all(isnan(txt(mode))), txt = '';
						else txt = num2str(txt(mode));
						end;	
					elseif length(txt) >= mode(1)
						if all(isnan(txt(mode(1)))), txt = '';
						else txt = num2str(txt(mode(1)));
						end
					else 
						txt = default;
					end
				else
                    txt = num2str(txt);
				end
            elseif txt(1) == ''''
                txt = txt(2:end-1); % remove quotes for text
			end
		else
			txt = default;
		end
	end
	%fprintf('%s:%s\n', var, txt);