rel2fullfile(files,refpath)

function files = rel2fullfile(files,refpath)
%REL2FULLFILE   Build full filename from relative file name
%   REL2FULLFILE(RELFILE,PATH) builds a full file name from the relative
%   path name RELFILE with respect to PATH. RELFILE may be a cellstr array
%   of file names.
%
%   REL2FULLFILE(RELFILE) builds the full filename using the current
%   MATLAB working directory as PATH.
%
%   See also relfile, fileparts, fullfile, filesep.

% Written by: Takeshi Ikuma
% Date: 10/31/2009
% Revision History:
%  (12/03/2010) allow '/' as the file separator in Windows
%  (01/19/2011) allow multiple files to be converted at once

error(nargchk(1,2,nargin));

if nargin<2, refpath = ''; end

if isempty(files), return; end
if isempty(refpath), refpath = pwd; end

% make sure the input is char not cellstr, convert if necessary
IS_CHAR = ischar(files);
if IS_CHAR
   files = cellstr(files);
elseif ~iscellstr(files)
   error('FILE must be a string or a cellstr array.');
end

if iscellstr(refpath), refpath = char(refpath); end
if ~ischar(refpath) || size(refpath,1)~=1
   error('PATH must be a string');
end

% for Windows platform, convert '/' to '\' in the pathnames
if filesep=='\' % WINDOWS==backslash as file separator
   files = strrep(files,'/','\');
   refpath = strrep(refpath,'/','\');
end

if refpath(end)==filesep % if reference path ends with file separator, remove it
   refpath = refpath(1:end-1);
end

for k = 1:numel(files)
   if strcmp(files{k}(1:2),'.\')
      files{k} = [refpath files{k}(2:end)];
   else
      N = length(files{k});
      i0 = 1;
      rpath = refpath;
      while N>=3 && strcmp(files{k}(i0:i0+2),'..\') && ~isempty(refpath)
         i0 = i0 + 3;
         N = N - 3;
         rpath = fileparts(rpath);
      end
      if rpath(end)==filesep
         files{k} = [rpath files{k}(i0:end)];
      else
         files{k} = [rpath filesep files{k}(i0:end)];
      end
   end
end

% Copyright (c)2009-2011, Takeshi Ikuma
% All rights reserved.
% 
% Redistribution and use in source and binary forms, with or without
% modification, are permitted provided that the following conditions are
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% 
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%     Redistributions in binary form must reproduce the above copyright
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%     documentation and/or other materials provided with the distribution.
%     * Neither the name of the <ORGANIZATION> nor the names of its
%     contributors may be used to endorse or promote products derived from
%     this software without specific prior written permission.
% 
% 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
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