mu=1/82.45;
mustar=1-mu;
r1=sqrt((x(1)+mu)^2+x(3)^2);
r2=sqrt((x(1)-mustar)^2+x(3)^2);
dx=[x(2)
2*x(4)+x(1)-mustar*(x(1)+mu)/r1^3-mu*(x(1)-mustar)/r2^3
x(4)
-2*x(2)+x(3)-mustar*x(3)/r1^3-mu*x(3)/r2^3];
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x0=[1.2;0;0;-1.04935751];%x0(i)對應與xi的初值
options=odeset('reltol',1e-8);%該命令的另壹種寫法是options=odeset;options.reltol=1e-8;
tic
[t,y]=ode45(@appollo,[0,20],x0,options);%t是時間點,y的第i列對應xi的值,t和y的行數相同
toc
plot(y(:,1),y(:,3))%繪制x1和x3,也就是x和y的圖形
title('Appollo衛星運動軌跡')
xlabel('X')
ylabel('Y')
Elapsed time is 0.597879 seconds.