scipy.signal.tf2zpk

scipy.signal.tf2zpk(b, a)

Return zero, pole, gain (z,p,k) representation from a numerator, denominator representation of a linear filter.

Parameters :

b : ndarray

numerator polynomial.

a : ndarray

numerator and denominator polynomials.

Returns :

z : ndarray

Zeros of the transfer function.

p : ndarray

Poles of the transfer function.

k : float

System gain.

If some values of b are too close to 0, they are removed. In that case, a :

BadCoefficients warning is emitted. :