Running same program is giving different plot

Everytime I run a program I get different plot for error. Why is that? How to resolve this issue? Please help

clear all; close all; clc;
%value of constants
a=0.1;
omega=5;
dt=0.01;   %step size
x(1)=1;
y(1)=1;
for i=2:1000
    x(i)=x(i-1)+((a-x(i-1)^2-y(i-1)^2)*x(i-1)-omega*y(i-1))*dt;
    y(i)=y(i-1)+((a-x(i-1)^2-y(i-1)^2)*y(i-1)+omega*x(i-1))*dt;
end
    index=randi([2,999],1,N_m);
    

[Rafael Hernandez-Walls]

maybe it's because you're using this command: index=randi([2,999],1,N_m);

Answer 1

[Rik]

Clear all should only exist exactly once in your entire code base. Replace it with clear or clearvars.

If you want to have repeatable code with randomness you will have to set the random seed. You can use the rng function to do so.