# scipy.signal.ZerosPolesGain¶

class scipy.signal.ZerosPolesGain(*system)[source]

Linear Time Invariant system class in zeros, poles, gain form.

Represents the system as the transfer function $$H(s)=k \prod_i (s - z[i]) / \prod_j (s - p[j])$$, where $$k$$ is the gain, $$z$$ are the zeros and $$p$$ are the poles.

Parameters: *system : arguments The ZerosPolesGain class can be instantiated with 1 or 3 arguments. The following gives the number of input arguments and their interpretation: 1: lti system: (StateSpace, TransferFunction or ZerosPolesGain) 3: array_like: (zeros, poles, gain)

Notes

Changing the value of properties that are not part of the ZerosPolesGain system representation (such as the A, B, C, D state-space matrices) is very inefficient and may lead to numerical inaccuracies.

Attributes

 A A matrix of the StateSpace system. B B matrix of the StateSpace system. C C matrix of the StateSpace system. D D matrix of the StateSpace system. den Denominator of the TransferFunction system. gain num Numerator of the TransferFunction system. poles zeros

Methods

 bode([w, n]) Calculate Bode magnitude and phase data of a continuous-time system. freqresp([w, n]) Calculate the frequency response of a continuous-time system. impulse([X0, T, N]) Return the impulse response of a continuous-time system. output(U, T[, X0]) Return the response of a continuous-time system to input U. step([X0, T, N]) Return the step response of a continuous-time system. to_ss() Convert system representation to StateSpace. to_tf() Convert system representation to TransferFunction. to_zpk() Return a copy of the current ‘ZerosPolesGain’ system.

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