I have a transfer function(adsbygoogle = window.adsbygoogle || []).push({});

L(s) = A(s)/B(s)

that I call Ls.

However, when defining

H(s)= L(s)/(1+L(s))

by

things go wild. The highest exponent power doubles or so and I get several extra poles or zeros. What I should get isCode (Text):

%%

Ls =

-70.6s^2 - 2003 s + 3375

--------------------------

s^3 + 119.6 s^2 + 2806 s

%%

Hs = Ls / (1+Ls)

H(s) = A(s) / ( B(s)+A(s) )

which is the exact result. This I can achieve in matlab by

and the result from this are exactly the expected.Code (Text):[As,Bs] = tfdata(Ls,'v');

Hs= tf(As,Bs+As)

However, why wont

work?Code (Text):Hs = Ls / (1+Ls)

Are matlabs routines that bad? Or am I doing something wrong?

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# MATLAB Matlab transfer function problem

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