fopen() the file. Start a loop. fgetl() a single line from the file. If that fails, break out of the loop. regexp() with 'split' on '\t' to split the line in to a cell string of individual fields. Loop checking all of the fields. If any character in the field is not '-', '+', 'e', 'E', 'd', 'E', '.', a leading space, a trailing space, or one of the digits, then the field is definitely a string so store it; otherwise try to str2double() the field, and if that works store the floating point value and otherwise store the string. End of loop over the fields. Save the result of converting the fields of the line. End loop over the lines.
You know have a cell array of vectors of cell arrays. To convert it to .xls, you are going to have to find the longest of the lines and pad the other lines with empty fields. Once you have all of the lines the same, length, you can convert to a cell array matrix. Once you have that, submit it to xlswrite()
