MATLAB: How to check if two transfer functions are the same

==comparisoncontrolControl System ToolboxMATLABtftheorytransfer function

I want to verify that two transfer functions are equal.
For example:
Kc = 0.4262; Ti=1.35;
C1 = pidstd(Kc,Ti);
tf(C1)
s = tf('s');
Gc1 = Kc*(1+1/(Ti*s))
assert(tf(C1) == Gc1)
Raises:
Undefined operator '==' for input arguments of type 'tf'.
Also note:
Gc1
tf(C1)
Gc1 - tf(C1)
Gc1 =
0.5754 s + 0.4262
—————–
1.35 s
Continuous-time transfer function.
ans =
0.4262 s + 0.3157
—————–
s
Continuous-time transfer function.
ans =
0
Static gain.

Best Answer

isequal(tfdata(tf(C1) - Gc1), {[0]})
This will probably fail if there are delays in the tf.
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