clear;close all; k_dc = 1; w_n = 10; zeta = 0.2 s = tf('s'); G1 = k_dc*w_n^2/(s^2 + 2*zeta*w_n*s + w_n^2); subplot(3,1,1); pzmap(G1) xlim([-40,0]); pole(G1) subplot(3,1,2); step(G1,2); ylim([0,1.5]); subplot(3,1,3); rlocus(G1); xlim([-40,0]); ylim([-50,50]);