z1 = [-0.05+2.738156i -0.05-2.738156i -2.0]; p1 = [-1.797086+2.213723i -1.797086-2.213723i -0.262914+2.703862i -0.262914-2.703862i]; k1 = 4; sys1 = zpk(z1, p1, k1); [a1,b1,c1,d1] = ssdata(sys1) [num1,den1] = tfdata(sys1, 'v')