Specifications

zpk
16-232
16zpk
Purpose Specify zero-pole-gain models or convert LTI model to zero-pole-gain form
Syntax sys = zpk(z,p,k)
sys = zpk(z,p,k,Ts)
sys = zpk(M)
sys = zpk(z,p,k,ltisys)
sys = zpk(z,p,k,'Property1',Value1,...,'PropertyN',ValueN)
sys = zpk(z,p,k,Ts,'Property1',Value1,...,'PropertyN',ValueN)
sys = zpk('s')
sys = zpk('z')
zsys = zpk(sys)
zsys = zpk(sys,'inv') % for state-space sys only
Description zpk is used tocreatezero-pole-gainmodels(ZPKobjects) or to convertTF orSS
models to zero-pole-gain form.
Creation of Zero-Pole-Gain Models
sys = zpk(z,p,k) creates a continuous-time zero-pole-gain model with zeros
z, poles p, and gain(s) k.Theoutputsys is a ZPK object storing the model data
(see “LTI Objects” on page 2-3).
In the SISO case,
z andp are the vectors of real or complex conjugate zerosand
poles, and
k is the real-valued scalar gain.
Set
z or p to [] for systems without zeros or poles. These two vectors need not
have equal length and the model need not be proper (that is, have an excess of
poles).
You can also use rational expressions to create a ZPK model. To do so, use
either:
•
s = zpk('s') to specifya ZPK model froma rational transfer function of the
Laplace variable,
s.
hs
()
k
sz1
()
–
()
sz2
()
–
()
... szm
()
–
()
sp1
()
–
()
sp2
()
–
()
... spn
()
–
()
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