lorenz.m

分形计算的几个程序原码

% 关于求解变参数lorenz方程 
fun=inline(['[-b*x(1)+x(2)*x(3);',... 
           '-xigma*(x(2)-x(3));',... 
           'r*x(2)-x(3)-x(1)*x(2)]'],... 
           't','x','flag','xigma','r','b'); 
xigma=10;b=8/3; 
rr=0.1:.1:3; 
Data_T=cell(length(rr),1); 
Data_X=cell(length(rr),1); 
tspan=[0,10]; 
x0=[0,0,1e-10]; 
for k=1:length(rr); 
   r=rr(k); 
   [T,X]=ode45(fun,tspan,[0,0,1],[],xigma,r,b); 
   Data_T(k)={T}; 
   Data_X(k)={X}; 
end 
p=randperm(length(rr));p(2:end)=[]; 
plot(cell2mat(Data_T(1)),cell2mat(Data_X(1))); 
title(['p=',num2str(p)]); 
A=cell2mat(Data_X(p)); 
figure;plot3(A(:,1),A(:,2),A(:,3)); 
title(['p=',num2str(p)]);