%2 similar linear systems, from linearizations of a non-linear system near
%the same operating point:

A13 = [     0            0            1            0            0
            0            0            0            1            0
       7.1734       5.6294      -0.6656     -0.65056       19.113
       -9.028      -6.8216        4.201      0.67742       29.001
            0            0            0            0      -25.316 ];

B13 = [     0            0      -19.113      -29.001       25.316 ]';

A15 = [     0            0            1            0            0
            0            0            0            1            0
       38.745      -4.3815     -0.20072     -0.17473       14.743
      -58.417       55.126      0.91003      0.04924       13.044
            0            0            0            0      -25.316 ];

B15 = [     0            0      -14.743      -13.044       25.316 ]';

%System 13 is closer to state uncontrollabilty, as the smallest singular
%value is nearer to zero:

svd(ctrb(A13,B13))
svd(ctrb(A15,B15))

%But the controller effort is much higher for system 15 (and in fact
%impossible)

K13 = acker(A13,B13,-0.3*ones(5,1))
K15 = acker(A15,B15,-0.3*ones(5,1))

%Both are tolerably successful pole placement designs otherwise:

eig(A13)
eig(A13-B13*K13)
eig(A15)
eig(A15-B15*K15)
