clear nu=0.5; Omega=1; kappa=0.001; dt=0.001; endt=2*pi*10; Nt=floor(endt/dt)+1 x=zeros(Nt,1); y=x; t=x; x(1)=2; y(1)=0; t(1)=0; tic r=randn(Nt,2); for n=1:(Nt-1) x(n+1)=x(n)+dt*(nu*(1-x(n)^2-y(n)^2)*x(n)-Omega*y(n))+sqrt(2*kappa*dt)*r(n,1); y(n+1)=y(n)+dt*(nu*(1-x(n)^2-y(n)^2)*y(n)+Omega*x(n))+sqrt(2*kappa*dt)*r(n,2); t(n+1)=t(n)+dt; end figure plot(x,y,'b-') toc