```# 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
```