Cse

clc
clear all
num=[1];
den=[1 4 3 0];
sys=tf(num,den)
rlocus(sys)
%Example
num1=[1];
den1=[1 8 19 12];
sys1=tf(num,den1)
rlocus(sys1)
%Example of addition of a simple zero at s=-4
num2=[1 4];
den2=[1 4 3 0];
sys2=tf(num2,den2)
rlocus(sys2)
%Example of addition of a complex zero at s^2=-4
num3=[1 0 4];
den3=[1 4 3 0];
sys3=tf(num3,den3)
rlocus(sys3)
%Example of addition of a complex pole at s^2=-4
num4=[1];
den4=[1 4 7 16 12];
sys4=tf(num4,den4)
rlocus(sys4)