lab4.m

利用龙格库塔法（等步长

figure(1)
clear all

global N hx
N=40;
hx=1/N;
x=hx:hx:1-hx;
u0=zeros(1,N);
u0=u0';
t0=0;tend=2;
options=odeset('Jacobian',jacobian)
t1=cputime;
[time,result]=ode23s(@fpar,[t0,tend],u0);
t2=cputime;
t2-t1
for i=1:size(time)
    if time(i)<=1&&time(i)>=0
        A(i)=1;
    else
        A(i)=0;
    end
end
% resultp=[A' result];
% xp=0:hx:1;
% surf(xp,time,resultp)
% xlabel('rod length variable x')
% ylabel('time variable t')
% zlabel('temperature variable T')
% 
% 
% 
% n=length(time);
% for i=2:n
%     tmax=time(i)-time(i-1);
% end
%     mn=max(tmax)