Specifications

tf
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If all SISO entries of a MIMO transfer function have the same denominator,
you can set
den to the row vector representation of this common denominator.
See “Examples” for more details.
sys = tf(num,den,Ts) creates a discrete-time transfer function with sample
time
Ts (in seconds). Set Ts = -1 or Ts = [] to leave the sample time
unspecified. The input arguments
num and den are as in the continuous-time
case and must list the numerator and denominator coefficients in descending
powers of .
sys = tf(M) creates a static gain M (scalarormatrix).
sys = tf(num,den,ltisys) creates a transfer function with generic LTI
properties inherited from the LTI model
ltisys (including the sample time).
See “Generic Properties” on page 2-26 for an overview of generic LTI
properties.
There are several ways to create LTI arrays of transfer functions. To create
arrays of SISO or MIMO TF models, either specify the numerator and
denominator of each SISO entry using multidimensional cell arrays, or use a
for loop to successively assign each TF model in the array. See “Building LTI
Arrays” on page 4-12 for more information.
Any of the previous syntaxes can be followed by property name/property value
pairs
'Property',Value
Each pair specifies a particular LTI property of the model, for example, the
input names or the transfer function variable. See
set entry and the example
below for details. Note that
sys = tf(num,den,'Property1',Value1,...,'PropertyN',ValueN)
is a shortcut for
sys = tf(num,den)
set(sys,'Property1',Value1,...,'PropertyN',ValueN)
Transfer Functions as Rational Expressions in s or z
You can also use real-valued rational expressions to create a TF model. To do
so, first type either:
z