% Script e3 partial-fraction expansion and impulse response
  clear % removes all variables from the workspace
  numG = [3 2]  % Create numerator
  denG = [2 4 5 1] % … & denominator polynomials
  G = tf(numG,denG) % create TF object
  pause
 [zG,pG,kG] = zpkdata(G,'v') %Extract poles and zeros from TF form
  pause
 [resG,polG,otherG] = residue(numG,denG) %Do partial-fraction
 % expansion to get residues at each pole
  pause
  impulse(G); grid
  %title('Ex 3 - impulse response');