MATLAB: Quick question for pade function

Control System Toolboxpade

[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?

Best Answer

  • [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.