basic knowledge question for loops

write a for loop that fills in this vector (all zeros, length 5) with the squares of the integers from 1 to 5. This for loop should iterate over 1 to 5, square each one, and add it to the vector.

How would I go about doing this? I have

a= zeros(1,5)
b= [1 2 3 4 5]
for i= 1:5
   y= b.^ i
   a= sum(y
end

but im confused on how to add each component to itself as it is going through the loop. If you could explain your code, that would be appreciated!

Answer 1

[James Tursa]

You made a decent start so I will help. Your code paired up with the instructions:

a= zeros(1,5)
b= [1 2 3 4 5]
for i= 1:5  %  iterate over 1 to 5
   y= b.^ i  % square each one
   a= sum(y  % add it to the vector
end

The "iterate over 1 to 5" looks good.

The "square each one" I think means square each index. So instead of b.^i you would have i^2.

The "add it to the vector" I think means add it to the corresponding spot in a. So a(i) = a(i) + y.

[Connor Pomeroy]

how can a(i) be on both sides of the equation? That doesn't make sense. So, b(i)= a(i) +y?

[James Tursa]

a(i) being on both sides of the equation makes perfect sense. It does exactly what the instructions say: "add it to the vector". "it" in this case is y. The "vector" in this case is a. The spot in question is the i'th spot. So the expression "a(i) + y" adds y to the i'th spot of a, and then stores the result right back into the i'th spot of a.

[Matt J]

how can a(i) be on both sides of the equation? That doesn't make sense.

It is not an equation (this is code), it's an assignment operation.

However, I think what is really being asked for is

a(i)=y;