time   calls  line
                585 function [status, numHeaderCols, numHeaderChars] = isvaliddata(fileString, delim)
                586 % ISVALIDDATA delimiters and all numbers or e or + or . or -
                587 % what about single columns???
                588 
             4  589 numHeaderCols  = 0; 
             4  590 numHeaderChars = 0; 
                591 
             4  592 if isempty(delim.printed) 
                593     % with no delimiter, the line must be all numbers, +, . or -
                594     status = isdata(fileString);
                595     return
                596 end
                597 
             4  598 status = 0; 
             4  599 if ~strcmp(delim.printed,'"') 
             4  600     fileString = regexprep(fileString, '"[^"]*"','""'); 
             4  601 end 
             4  602 delims = strfind(fileString, delim.printed); 
             4  603 if isempty(delims) 
                604     checkstring = fileString;
                605     if isempty(regexp(checkstring, '\S', 'once'))
                606         % Just a blank line, not actually data.
                607         status = 0;
                608         return
                609     end
             4  610 else 
             4  611     checkstring = fileString(delims(end)+1:end); 
             4  612 end 
                613 
                614 % if there is data at the end of the line, it's legit
             4  615 if isdata(checkstring) 
             4  616     try 
  0.01       4  617         [cellstring indices] = split(fileString, delim);  
             4  618         numNonEmptyCols = find(cellfun('isempty',deblank(cellstring)) == false, 1, 'last'); 
  0.01       4  619         numHeaderCols = maxNotData(cellstring);  
                620 		% use contents of 1st data cell to find num leading chars
             4  621         if numHeaderCols > 0 
                622             numHeaderChars = indices(numHeaderCols);
                623         end
             4  624         if (numHeaderCols == numNonEmptyCols) 
                625             numHeaderCols = 0;
                626             numHeaderChars = 0;
             4  627         else 
             4  628     		status = 1; 
             4  629         end 
                630     catch exception  %#ok<NASGU>
                631         numHeaderCols = 0;
                632         numHeaderChars = 0;
                633     end
             4  634 end 

Other subfunctions in this file are not included in this listing.