Matlab polynomial basics: roots, derivative of polynomial, evaluate polynomial

%Get roots of function

octave-3.2.3:13> A = [1 -3 3 -1]
A =

   1  -3   3  -1

octave-3.2.3:14> roots(A)
ans =

   1.00001 + 0.00000i
   1.00000 + 0.00001i
   1.00000 - 0.00001i

%get derivative of polynomial

octave-3.2.3:18> A
A =

   1  -2   1

octave-3.2.3:19> polyder(A)
ans =

   2  -2


%evaluate polynomial using matrix notation

 polyval(A,1)
ans = 0
octave-3.2.3:21> polyval(A,2)
ans =  1