为什么非自治系统的相轨线会相交

2025-04-24 18:46:52
推荐回答(1个)
回答1:

ts = 0:50;i0 = 0.02;s0 = 0.98;x0=[i0;s0];[t,x]=ode45(@sirfun,ts,x0);figure; plot(x(:,2),x(:,1)); grid on; function dy = sirfun(t,x)% x(1)--> i, x(2)-->s% di/dt = λsi-μi% ds/dt = -λsi lambda = 1; mu = 0.3; dy = [lambda*x(1)*x(2)。