System representation coversion

You can convert from transfer function to zero-pole representation and vica versa using the following commands

>> [n,d]=zp2tf(z,p,k)

n =

    0.5000         0   -1.0000         0    0.5000


d =

     1     0     2     0     1

>> [z,p,k]=tf2zp(num,den)

z =

        0 + 1.4142i
        0 - 1.4142i


p =

   -3.1583
    0.1583


k =

     1