function my_tf2ss_tst

for i=2:5
    for j=1:i-1
        den= rand(1,i); den(1)=1;
        num= rand(1,j);
        [A,B,C,D]= my_tf2ss(num, den);
        [n,d]= ss2tf(A,B,C,D,1);
        err= [zeros_prefix(num, den)-n  den-d];
        disp(max(abs(err)))
    end
end


function y= zeros_prefix(num, den)
nn= length(num);
nd= length(den);
y= [zeros(1,nd-nn) num];