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clear;//Parametersmu=0.2;B=0.35;gamma=8;nu=1.02// van der Pol and Duffing mixed type equation, x=x(1), y=x(2)functiondx=POLDUFF(t,x)dx(1)=x(2);dx(2)=mu*(1-gamma*x(1)^2)*x(2)-x(1)^3+B*cos(nu*t);endfunction// The time range and step for calculationTout=900;Tstep=0.01;t=0:Tstep:Tout;// The initial valuesx0=0.5;y0=0.5;X0=[x0;y0];X=ode(X0,0,t,POLDUFF);Tin=5000;Tmax=Tout/Tstep;clf;plot(X(1,[Tin:Tmax]),X(2,[Tin:Tmax]))xlabel('x')ylabel('y')