User`s guide

zpk
11-239
• s = zpk('s') to specify a ZPK model from a rational transfer function of the
Laplace variable,
s.
•
z = zpk('z',Ts) to specify a ZPK model with sample time Ts from arational
transfer function of the discrete-time variable,
z.
Once you specify either of these variables, you can specify ZPK models directly
as real-valued rational expressions in the variable
s or z.
To create a MIMO zero-pole-gain model, specify the zeros, poles, and gain of
each SISO entry of this model. In this case:
•
z and p arecellarraysofvectorswithasmanyrowsasoutputsandasmany
columns as inputs, and
k is a matrix with as many rows as outputs and as
many columns as inputs.
• The vectors
z{i,j} and p{i,j} specify the zeros and poles of the transfer
function from input
j to output i.
• k(i,j) specifies the (scalar) gain of the transfer function from input j to
output
i.
See below for a MIMO example.
sys = zpk(z,p,k,Ts) creates a discrete-time zero-pole-gain model with
sample time
Ts (in seconds). Set Ts = –1 or Ts = [] to leave the sample time
unspecified. The input arguments
z, p, k are as in the continuous-time case.
sys = zpk(M) specifies a static gain M.
sys = zpk(z,p,k,ltisys) creates a zero-pole-gain model with generic LTI
properties inherited from t he LTI model
ltisys (including the sample time).
See “Generic Properties” on page 2-26 for an overview of generic LTI
properties.
To create an array of ZPK models, use a
for loop, o r use multidimensional cell
arrays for
z and p, and a multidimensional array for k.
Any of the previous syntaxes can be followed by property name/property value
pairs.
'PropertyName',PropertyValue