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问题描述:

I am writing a code and I am stuck in this problem. I have a summation that goes from 1 to a certain number, but one of the elements in the function including access to row/column zero (which is not allowed in Matlab).

So, for example:

Let say v= 1 : 10

And the function is:

S(v) + M(v) S(v-1)

I need to tell Matlab that if you get S(0) return a value of Zero.

So for v=1 we get S(1)
For v=2 we get S(2)+M(2) S(1)
For v=3 we get S(3)+M(3) S(2)

And so on.

Is there a way to do that?

Thank you.

网友答案:

Here's what I would have done: (res stores the result of the equation)

res(1)=S(1);

for v=2:10
  res(v)=S(v)+M(v).*S(v-1);
end;

网友答案:

What if I have a complex function with ascending and descending index.

The function that I am trying to code is:

S(1) + (S(2)+M(1)*S(1))X + (S(3)+M(1)*S(2)+M(2)*S(1))X^2 + ...

So, you can have it as:

(S(v)+M(1)*S(v-1)+...+M(v-1)*S(1)) X^v-1

网友答案:

If you are using functions, you can return anything you want when zero is passed in.

For matrices, indexing is always one-based. Usually t=0 is represented by A(1). So just add one.