scipy.signal.ZerosPolesGain

class scipy.signal.ZerosPolesGain(*system)

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.