    # This is test comment
    % this is another comment
    a = 3; b = 34;

    function retval = avg (v)
      retval = 0;
      if (isvector (v))
        retval = sum (v) / length (v);
      else
        error ("avg: expecting vector argument");
      endif
    endfunction

    if (rem (x, 2) == 0)
      printf ("x is even\n");
    else
      printf ("x is odd\n");
    endif

    if (rem (x, 2) == 0)
      printf ("x is even\n");
    elseif (rem (x, 3) == 0)
      printf ("x is odd and divisible by 3\n");
    else
      printf ("x is odd\n");
    end

    if (rem(x,2) == 0) x = 5; elseif (rem (x,3) == 0) x = 3; else x = 0; end

    cd ..

    while (i <= 10)
      fib (i) = fib (i-1) + fib (i-2);
      i++;
    endwhile

    classdef polynomial2
      properties
        poly = 0;
      endproperties

      methods
        function p = polynomial2 (a)
          if (nargin > 1)
            print_usage ();
          endif

          if (nargin == 1)
            if (isa (a, "polynomial2"))
              p.poly = a.poly;
            elseif (isreal (a) && isvector (a))
              p.poly = a(:).';  # force row vector
            else
              error ("polynomial2: A must be a real vector");
            endif
          endif
        endfunction

        function disp (p)
          a = p.poly;
          first = true;
          for i = 1 : length (a);
            if (a(i) != 0)
              if (first)
                first = false;
              elseif (a(i) > 0 || isnan (a(i)))
                printf (" +");
              endif
              if (a(i) < 0)
                printf (" -");
              endif
              if (i == 1)
                printf (" %.5g", abs (a(i)));
              elseif (abs (a(i)) != 1)
                printf (" %.5g *", abs (a(i)));
              endif
              if (i > 1)
                printf (" X");
              endif
              if (i > 2)
                printf (" ^ %d", i - 1);
              endif
            endif
          endfor

          if (first)
            printf (" 0");
          endif
          printf ("\n");
        endfunction
      endmethods
    endclassdef