How to Rewrite This Section of Code as a For Loop

Do you know how a for loop equivalent for this would look like? I can't seem visualize what it would look like without having to make significant changes to the loop that I would have created: How can I compute the error without using the sum? I am not sure how to write it in terms of a loop. I am also not sure if I should use a for loop (given that the number of iterations will be the same as for the while loop) or if I should use the while loop:

This is the sevction of Code I want to convert to a for the purposes of a programming assignment that I have for engineering numerical methods:

function E=find_E(X_Prev, X_New);

termA = (X_New - X_Prev)^2;
termA = sum(termA(:))^0.5;
termB = X_New.^2;
termB = sum(termB(:))^0.5;

E = termA/termB;

Answer 1

[Steven Lord]

Conceptually, isn't taking the sum of an array of data just the same as repeatedly adding (+) each element to a running total? [The two implementations may not result in exactly, down-to-the-last-bit, identical answers in practice, but in theory shouldn't they match?]

[Cody Crouse]

Yeah, since loops are a repetition of a given task. I do not know how any elements that I have in my set, & I need to write the section as a loop to get around the ban on the sum function.

[Cody Crouse]

In addition, I am looking to rewrite this text of code as a loop:

function E = find_E(X_Prev, X_New)
    termA = (X_New - X_Prev).^2;
    termA = sum(termA(:))^0.5;
    termB = X_New.^2;
    termB = sum(termB(:))^0.5;
    E = termA/te

[Steven Lord]

Hint: take a look at the numel function.

Answer 2

[Walter Roberson]

termAsum = 0;
for term = termA(:).'
    termAsum = termAsum + term;
end

[Cody Crouse]

Does this serve as a resplacement for my code section? I am asking because I already that E = find_E(X_Prev, X_New) several times in my code. In addition, my term statements are underneath it.

[Walter Roberson]

That replaces

termA = sum(termA(:));

Note: it leaves out the ^0.5