A=[0 1 3 -1;0 -1 -2 2;-1 0 -2 -1;-1 0 -3 0]
b=[0;0;1;0]
c=[1 0 0 0]
eig(A)
p=[-3 -3 -3 -3]
l=transpose(acker(transpose(A),transpose(b),p))
eig(A-l*c)