What wrong in line 12 ?? help me please (Index exceeds matrix dimensions.)

4 次查看（过去 30 天）
Bui Thien Phuc
Bui Thien Phuc 2019-4-9
编辑： Torsten 2019-4-10
clear
close all;
N=10;
h = 0.5;
u1(1)= 2 ;
u2(1)= 3 ;
u3(1)=0 ;
t(1) = 0;
for n=1:N
u3(n+1)=u1(n)+h*u2(1);
u1(n+1)=u1(n)+1/2*(4*exp(0.8*t(n))-0.5*u1(n)+4*exp(0.8*t(n+1))-0.5*u3(n));
t(n+1)= t(n) + h ;
end
plot(t,u1);

请先登录，再回答此问题。

回答（2 个）

Alex Mcaulley
Alex Mcaulley 2019-4-9
In this line:
u1(n+1)=u1(n)+1/2*(4*exp(0.8*t(n))-0.5*u1(n)+4*exp(0.8*t(n+1))-0.5*u3(n));
the length of t is n, then t(n+1) gives an error
  6 个评论
显示 4更早的评论
Bui Thien Phuc
Bui Thien Phuc 2019-4-9
just answer me I want to use u2(1) only one time in first circle so I did right ?
Torsten
Torsten 2019-4-10
编辑：Torsten 2019-4-10
If you use your code: no.
If you use Alex's second code: yes.

请先登录，再进行评论。

Torsten
Torsten 2019-4-9
clear
close all;
N = 10;
h = 0.5;
u1(1) = 2 ;
u2(1) = 3 ;
u3(1) = 0 ;
t = 0:h:N*h;
for n = 1:N
u3(n+1) = u1(n)+h*u2(1);
u1(n+1) = u1(n)+1/2*(4*exp(0.8*t(n))-0.5*u1(n)+4*exp(0.8*t(n+1))-0.5*u3(n));
end
plot(t,u1);

类别

在 Help Center 和 File Exchange 中查找有关 Creating and Concatenating Matrices 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by