Hi 가현,
The following expression 'plot(t,sys)' will result in an error since 'sys' is a dynamic system model, and the 'plot' function will not accept a model as input. The line 'plot(t,sys)' can be removed because the 'impulse' function plots the impulse response of 'sys'
t = 0:0.01:15;
A = [-1 -1;6.5 0];
B = [1 1;1 0];
C = [1 0;0 1];
D = [0 0;0 0];
sys = ss(A,B,C,D);
impulse(sys,t); % this syntax will plot the impulse response
[y,t,x] = impulse(sys,t);
y1 = [1 0]*y(:,:,1)' + [1 0]*y(:,:,2)';
y2 = [0 1]*y(:,:,1)' + [0 1]*y(:,:,2)';
figure(1)
% plot(t,sys)
xlabel('Time,(s)')
ylabel('y')
grid;
legend('y')
figure(2)
subplot(211);
plot(t, y1); grid
ylabel('y_1')
subplot(212);
plot(t, y2); grid
xlabel('t (sec)'); ylabel('y_2')
For more information on 'impulse' function, refer the following MATLAB documentation - https://www.mathworks.com/help/ident/ref/dynamicsystem.impulse.html
