get_BADC_data

 Child function to do the actual downloading from the BADC site via FTP.
 If the remote file doesn't exist, the function continues to the next file
 warning that the file couldn't be found. You may end up with gaps if the
 Met Office don't have those data (e.g. the 31st July 2010 doesn't have
 any model results, for some reason).
 
 INPUTS:
   site - FTP server name (e.g. ftp.ceda.ac.uk')
   filepath - path to the files to download
   files - cell array of a file or files to download
   credentials - optional cell array of {'username', 'password'}.
 
 OUTPUTS:
   tfiles = cell array of files downloaded. NaN = failed to download.

 WARNING:
   This function will indiscriminately overwrite files in the destination
   directory (which is the system temporary directory appended with
   'metum').

0001 function tfiles = get_BADC_data(site, filepath, files, varargin)
0002 % Child function to do the actual downloading from the BADC site via FTP.
0003 % If the remote file doesn't exist, the function continues to the next file
0004 % warning that the file couldn't be found. You may end up with gaps if the
0005 % Met Office don't have those data (e.g. the 31st July 2010 doesn't have
0006 % any model results, for some reason).
0007 %
0008 % INPUTS:
0009 %   site - FTP server name (e.g. ftp.ceda.ac.uk')
0010 %   filepath - path to the files to download
0011 %   files - cell array of a file or files to download
0012 %   credentials - optional cell array of {'username', 'password'}.
0013 %
0014 % OUTPUTS:
0015 %   tfiles = cell array of files downloaded. NaN = failed to download.
0016 %
0017 % WARNING:
0018 %   This function will indiscriminately overwrite files in the destination
0019 %   directory (which is the system temporary directory appended with
0020 %   'metum').
0021 
0022 global ftbverbose
0023 
0024 assert(iscell(files), 'Provide a cell array of files to download')
0025 
0026 tdir = fullfile(tempdir, 'metum');
0027 
0028 if exist(tdir, 'dir') ~= 7
0029     mkdir(tdir)
0030 end
0031 
0032 nf = length(files);
0033 
0034 tfiles = cell(nf, 1);
0035 
0036 for j = 1:nf
0037     % Open a remote connection to the FTP site. I found that the timeout on
0038     % the FTP connection to ftp.ceda.ac.uk is pretty low, so it's best to
0039     % explicitly re-open it each time we want a bunch of new files.
0040     if nargin == 3
0041         remote = ftp(site);
0042     elseif nargin == 4
0043         remote = ftp(site, credentials(1), credentials(2));
0044     end
0045     S = whos('remote');
0046     assert(strcmpi(S.class, 'ftp'), 'remote is not an FTP class. See HELP FTP.')
0047     clear S
0048     
0049     try
0050         cd(remote, filepath);
0051     catch
0052         warning('No such path %s (file %s)', filepath, files{j})
0053         continue
0054     end
0055 
0056     try
0057         if ftbverbose
0058             fprintf('Downloading %s to %s\n', fullfile(site, filepath, files{j}), tdir)
0059         end
0060         tfiles{j} = mget(remote, files{j}, tdir);
0061     catch
0062         tfiles{j} = nan;
0063         warning('Failed to fetch data from %s', fullfile(site, filepath, files{j}))
0064     end
0065     
0066     % Close the connection to the FTP server.
0067     close(remote)
0068 end
0069