Pulling values from vectors

I have two fairly basic questions about pulling values from vectors.

n=0:40;
i=n+1
income(i) = initial_income*(1+inflation).^(n)
income(1)

My goal is to pull the second vector from the list while using 1 as the indicator. I'm working in terms of years and income(1) doesn't justify the first year. It amounts to the initial value. I need income(1) to be what currently is income(2) and income(2) to be income(3) so on so forth. How can I manage to do this?

Here's my second question. I know income(1) pulls the first value, but what does income(i) imply? I'm under the assumption that it needs to be used here, but I also want to make sure I understand the reasons why I would use it.

Let me know if anymore information is needed. Thanks!

Answer 1

[Matt J]

but what does income(i) imply? I'm under the assumption that it needs to be used here

Nope. It doesn't:

income = initial_income*(1+inflation).^(1:40);

[Nathan Brannan]

But how about in the case that I want i = n+1 so that income(1) actually pulls the value of income(2)?

So like:

income(i) = income(n+1)
% therefore income(1) is no longer the first value but the second value.

Sorry if this doesn't make sense.

[Matt J]

You mean you want to start with a vector income and then have the values stored in the vector shift locations? There are a number of different ways to do that, depening on what you intend for the final value:

income=randi(100,1,5) %example

income = 1×5

15 74 77 9 90

incomeShifted=income(2:end)  %truncated shift

incomeShifted = 1×4

74 77 9 90

incomeShifted=circshift(income,-1) %circulant shift

incomeShifted = 1×5

74 77 9 90 15

incomeShifted=[income(2:end) , 0] %padded shift

incomeShifted = 1×5

74 77 9 90 0

[Nathan Brannan]

That's exactly what I was looking for!

Thank you!