pan>(isempty(filename))
0023    [fname, pathname] = uigetfile(<span class="string">'*.ddt'</span>, <span class="string">'Select a ddt file'</span>);
0024     filename = strcat(pathname, fname);
0025 <span class="keyword">end</span>
0026 fid = fopen(filename, <span class="string">'r'</span>);
0027 <span class="keyword">if</span>(fid == -1)
0028     disp(<span class="string">'cannot open file'</span>);
0029    <span class="keyword">return</span>
0030 <span class="keyword">end</span>
0031 disp(strcat(<span cla