Index exceeds matrix dimensions

Hi,

I am trying to make a for loop, however the code I am using turns out the error : index exceeds matrix dimensions, I can't quite work out what I am doing wrong.

my code is below:

S1=1.7*1.2
U=1.5
Tout=5
for index=1:1:30 
        %Ambient Load
        Ts=Ts(index-1)
        Tin=Tin(index-1)
       
        S1QAmb=S1*U*(Tout-(2*Ts)+Tin)     %surface 1, ambient load
end       

[Adam]

Ts is not defined anywhere.

If it where then I would expect the first error you get would be that indices must be real positive values since

index-1

will clearly be 0 on the first time round the loop, which is not a valid index into an array.

[Jamil Dudhwala]

Is this more to do with the fact that I have not intialised it?

[Adam]

If that is lterally all your code then of course it will not work. What are you expecting the result to be of indexing into a variable that does not exist yet?

Answer 1

[KSSV]

A = rand(5,1) ;   % an array of size 5*1 
A(1)  % works 
A(5)  % works
A(6)  % throws error

The above array has only 5 elements....If you try to extract more than 5 elements, it will throw error.