num1=[1 3];
den1=[1 3 2];
[r,p,k]=residue(num1,den1);
p

p =

    -2
    -1

r

r =

    -1
     2

num1=[5 3];
den1=[1 6 11 6];
[r,p,k]=residue(num1,den1);
r

r =

   -6.0000
    7.0000
   -1.0000

num1=[2 12];
den1=[1 2 5];
[r,p,k]=residue(num1,den1);
r

r =

   1.0000 - 2.5000i
   1.0000 + 2.5000i

num1=[1 2 3];
den1=[1 3 3 1];
[r,p,k]=residue(num1,den1);
r

r =

    1.0000
    0.0000
    2.0000

diary off