function xdot=lorenz(t,x)
a=10;b=28;c=8/3;
xdot=[a*(x(2)-x(1));b*x(1)-x(2)-x(1)*x(3);x(1)*x(2)-c*x(3)];
%xdot=[-8/3*x(1)+x(2)*x(3);-8620*x(2)+8620*x(3);-x(1)*x(2)+144*10^7*x(2)-x(3)];

 

%lorenz方程的相圖
%clear all;
%option=odeset('AbsTol',1e-6,'Reltol',1e-4); 
%[t,y]=ode45(@lorenz,[0,100],[0.000296 -0.000635 -0.000654],option);
%plot3(y(:,1),y(:,2),y(:,3));
%title('lorenz方程相圖');
%xlabel('x');ylabel('y');zlabel('z');grid;
%figure;
%plot3(y(:,1),y(:,2),y(:,3));
%title('lorenz方程x-y圖');
%xlabel('x');ylabel('y');grid;view(0,90);
%figure;plot3(y(:,1),y(:,2),y(:,3));
%title('lorenz方程的x-z圖');xlabel('x');zlabel('z');grid;view(180,0);
%figure;plot3(y(:,1),y(:,2),y(:,3));
%title('lorenz方程的y-z圖');ylabel('y');zlabel('z');grid;view(90,0);