Index Exceeds Matrix Dimensions error in For Loop

Hello,

As the title says, I keep on getting this error and not too sure how to fix it, as I am not too familiar with MATLAB.

A shortened version of the code is as followed:

L=10;
T(1)=200;
for i=2:(L-1)
    F(i)=T(i-1);
end

Ultimately, I will have three different functions, F1, F2, and F3, that call T(i-1), T(i), and/or T(i+1) as i runs from 2 to (L-1), but the T(1) will be given, which is why I begin my loop with T(i-1), so I can call the previous T(i) value for the new i, if that makes sense.

But to make things simple, I just included this smaller, simplified version since I'm assuming if I can fix this error I can figure out what to do for the longer code.

Any help is appreciated, thank you. I can give more details if need be as well.

Answer 1

[randerss simil]

%if true
L = 10;
F1 = zeros(1,L)
F2 = zeros(1,L)
F3 = zeros(1,L)
T1(1)=200;
T2 = zeros(1,L);
T3 = zeros(1,L);
T3(3)=400;%e.g.
F1(1,1) = 0;
F2(1,1) = 0;
F3(1,1) = 0;
for i=2:(L-1)
  F1(i)=F1(i-1)+T1(i-1);
  F2(i)=F2(i-1)+T2(i);
  F3(i)=F3(i-1)+T3(i+1);
end

[Jon Stapchuck]

So if I understand this correctly, we have to initially define all functions and variables used (in this case F1, F2, F3) such that they can run from 1 to L.

Thank you, I see your edits and will apply them. A difference is that I want my T values (besides certain initial and final ones) to be changing with i as well, but I can do that in a for loop as well.

Answer 2

[Walter Roberson]

T(1)=200;
for i=2:(L-1)
  F(i)=T(i-1);
end

You only initialize T(1) and you never assign to T(2) so when i becomes 3 you try to refer to T(2) which does not exist.

[Jon Stapchuck]

Yes that will do it haha, thank you very much.

Ultimately my plan is to have the T's be varying with i as well