Matlab Code for Output Feedback Stabilization

A=[0 1 0 0;10 -3 1 1;0 0 0 1;0 1 0 1]
B=[0;0;0;1]
C = [1 0 0 0]
con=ctrb(A,B);
r1=rank(con)
OBS=obsv(A,C);
r2=rank(OBS)
K=acker(A,B,[-1-i,-1+i,-5,-8])
% New state space model
xo = [1.2; 0.3; -0.4;2];
A1 = A-B*K;
N = -inv(C*(inv(A1))*B)
%Output Feedback Stabilization
P1 = [-1, -2, -3, -4];
H = place(A',C', P1)'