Euler Method keep getting an error for tvec=zeros(N+1,1)

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Kristian Torres 2020-7-2

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/558172-euler-method-keep-getting-an-error-for-tvec-zeros-n-1-1

评论： KSSV 2020-7-2

%Euler Method 
%Used to approximate f'(t,y)=y' y(1)=2
a=1; %left time endpoint
b=2; %right end point
N=10; % number odf steps
alpha=2; %initial condition
h=(b-a)/N;% width of each triangle;
wvec=zeros(N+1,1);%approximation solution vector
yvec=zeros(N+1,1);% real solution vector
tvec=zeros(N+1,1);time %vector
wvec(1)=alpha;
yvec(1)=alpha;
tvec(1)=a;
for i=2:N+1
    wvec(i)=wvec(i-1)+h*ftyy(tvec(i-1),wvec(i-1));
    tvec(i)=a+(i-1)*h;
    yvec(i)=2*tvec(i)+tvec(i)*log(tvec(i));
end
[t,z]=ode45(@ftyy,tvec,alpha);
T=table(tvec,wvec,yvec,abs(wvec-yvec),z,abs(z-yvec));
writetable(T,'EuulerS.xlsx')
plot(tvec,wvec,'r-',tvec,yvec,'b-',t,z,'r--')