Create a For Loop

Hi, the task is that:

S0 = 0;
S1 = S0+p1-q1-e1;
S2 = S1+p2-q2-e2;

and so on

p,q,and e are all known. I tried to write a for loop for it as following:

for i = 1:121
S(i) = S(i-1)+p(i)-q(i)-e(i);
S = S(i);
end

but S(i-1) gives S(0) which is not allowed in matlab.

Can anyone give me some advice on how to modify it to make it work?

Thank you!

Answer 1

[James Tursa]

Simply adjust your expectations of how to use indexing. E.g., let

S(1) mean the same thing as S0
S(2) mean the same thing as S1
etc

Then just adjust your indexing:

S(1) = 0;
for i = 2:122
    S(i) = S(i-1)+p(i)-q(i)-e(i);
end

Or, if the indexing of the p, q, e vectors already started at 1, then maybe this variation will work for you:

S(1) = 0;
for i = 2:122
    S(i) = S(i-1)+p(i-1)-q(i-1)-e(i-1);
end

[Ivy Shen]

Thank you very much!