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How can I use this application to reduce a system having A B C matrices

Hi,
I recognized that freqresp of an sss returns zero in case the system has poles at zero, for instance:

[A,B,C,D]=deal([0 1;0 0],[0;1],[1 0],0);
G1=ss(A,B,C,D);
G2=sss(G1);
freqresp(G1,2pi10) % = -2.5330e-04
freqresp(G2,2pi10) % = 0

I checked it with Matlab 2016b and 2018b, same result.

Would be great if you could solve it.

Regards,
TomGoZ