How to Design an Observer in MATLAB?

i want to design an observer for a dynamic system using this matlab code. thank you clc; clear; close all; ts = [0 80]; % Solving system dynamics sol = ddesd(@sig, @tau, @his, ts); t = sol.x; y = sol.y; % System delay function function d = tau(t, y) d = [1.5 + sin(0.5*t)]; end function s = his(t) s = [1;0]; end % System dynamics function function yp = sig(t, y, Z) ylag1 = Z(:,1); yp = [-0.2620*y(1) - 2.3748*y(2) + 0.5*ylag1(2) + exp(-t)*sin(y(1)) + 1/(1+t.^2)*y(1); -0.6550*y(1) - 8.4370*y(2) + 0.2*ylag1(1) - ylag1(2) + exp(-t)*sin(y(2)) + 1/(1+t.^2)*y(2)]; end

[Sam Chak]

@khawla mrad, can you edit the post? It is very uncomfortable to read the code. Click this icon , please.