quick question for pade function

[num den]=pade(100,1)

num =

     -1.0000    0.0200

den =

      1.0000    0.0200

>> num

num =

     -1.0000    0.0200

which one is poles and which one is residues?

Answer 1

[Paulo Silva]

[num den]=pade(100,1)

num= -s+0.02 -> one zero at s=0.02

den= s+0.02 -> one pole at s=-0.02

You can see the zeros and poles like this pzmap(tf(num,den)) , or the step response step(tf(num,den)), tip: change the order from 1 to 2 and see what happens to the step response.

From the documentation of the pade function:

The row vectors num and den contain the numerator and denominator coefficients in descending powers of s. Both are Nth-order polynomials.

[Amir Hamzah UTeM]

thanks Paulo,

so pole = -0.02 right? then what about residues?how can i get them?

[Paulo Silva]

Yes it's at s=-0.02

[r,p,k] = residue(num,den)

%[r,p,k] = residue(b,a) finds the residues, poles,

%and direct term of a partial fraction expansion

%of the ratio of two polynomials