线性时不变系统能控性的两种判据的结果不同

Question

对于线性时不变系统：x(t)=A x(t)+B u(t)。
当矩阵A为20阶方阵，矩阵B为20*10的矩阵时，在MATLAB中利用卡尔曼秩判据不满秩，
cont=ctrb(A,B) ;
rank(cont)

而利用PBH判据判定时为满秩
E=eye(size(A,1));
e=eig(A);
co=[e(1)*E-A B]；
rank（co）
这是什么原因？系统是能控吗？

A=
[
-3.69232078164495 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 -2.93473044981691 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 -2.68474345845086 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 -2.69502086937368 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 -2.19491200219141 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 -2.05120728727441 0 0 0 0 0 0 0 1.32771021120545 0 0 0 0 0 0
0 0 0 0 0 0 -2.46500397525483 0 0 0 0 0 0 1.23472426948259 0 0 0 0 0 0
0 0 0 0 0 0 0 -3.65819486148077 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 -2.83825522282220 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 -1.86850540510724 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 -2.26363748269409 0 0 0 0 0 0 0 0 0
0 0 0.769619044103623 0 0 0 0 0 0 0 0 -2.58155683607658 0 0 0 0.981688874327727 0 0 1.45371372753573 0
0 0 0.900031939486592 0 0 0 0 0 0 0 0 0 -3.30972057260847 0 0 1.17380392546535 0 0 1.08775923824798 0
0 0 0 1.46348363417127 0 0 0 0 0 0 0 0 0 -2.01786857064529 0 0 0 0 0 0.963364210961705
0 0 0 0.642816537541540 0 0 0 0 0 0 0 0 0 0 -2.48539480001656 0 0 0 0 1.13090767654839
0 0 0 1.48350504197245 0 0 0 0 0 0 0 0 0 0 0 -3.75434002085945 0 0 0 1.17980606196396
0 0 0 0 0.737905658496441 0 1.44584190943932 0.935260771253292 0 0 0 0 1.38210542229843 0 0 0 -1.85374526784438 0 0 0
0 0 0 0 0.890824931396292 0 1.14121605136104 1.07287655617198 0 0 0 0 0.953880662671819 0 0 0 0 -3.12531427012303 0 0
0 0 0 0 1.04976521572796 0 1.27057299702314 1.40918704824654 0 0 0 0 0.707078725610188 0 0 0 0 0 -3.04747594088094 0
0 0 0 0 0.918888351155640 0 0.601332803190076 0.580496146179822 0 0 0 0 0.702299929663958 0 0 0 0 0 0 -1.85776750467902
];

B=
[1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
1 0 0 0 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0 0
0 0 0 0 0 1 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 1 0 0 0
0 0 0 0 0 0 0 1 0 0
0 0 0 0 0 0 0 0 1 0
0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0
];