clear; close all; a = 6; q = 2.939; tspan = [0 100]; y0 = [0 0.01]; [t,y] = ode23s(@(t,y) odefun(t,y,a,q), tspan, y0); plot(t,y(:,1),'-r',t,y(:,2),'-b'); legend('x','v'); big; function dydt = odefun(t,y,a,q) dydt = zeros(2,1); dydt(1) = y(2); dydt(2) = -(a-2*q*cos(2*t))*y(1); end
安定
不安定(自励振動)