I have a program, and I want to know if this is what you want.
Clear all;
clc
a = 1.4; b = 0.3u = 1.0e-4;
x( 1)= 0.2; y( 1)= 0.5;
x 1( 1)= x( 1)+u; y 1( 1)= y( 1); Initial sensitivity%
p = 5000q = 40
For m=2:p
x(m)= 1+b*y(m- 1)-a*(x(m- 1))^2;
x 1(m)= 1+b*y 1(m- 1)-a*(x 1(m- 1))^2;
y(m)= x(m- 1);
y 1(m)= x 1(m)- 1;
end
h = 1:p;
plot(x(h),y(h));