Skipping Iterations in a For Loop

Hi there, I have a vector

FEM = [-16 16 -18 12 -6 6]

FEM = 1×6

-16 16 -18 12 -6 6

I want to add together (16 + -16), (-18 +_16). (12-18) and (6 + -6)

I have been trying to use a for loop with the code:

for i = 1:6-1
    FEM(i+1) + FEM(i) 
end

ans = 0

ans = -2

ans = -6

ans = 6

ans = 0

However, from this I get one extra value that I do not want as shown, which is postive 6. What I really want is just [0 -2 -6 0].

I did a quick look up and came across the 'continue' function which should skip an iteration. So I set up the code like this:

for i = 1:6-1
    FEM(i+1) + FEM(i) 
    if i ==3
        continue
    end
end

ans = 0

ans = -2

ans = -6

ans = 6

ans = 0

but look, I still get the five values instead of the four!

Could somebody help please?

Many thanks in advance!

Answer 1

[Voss]

Basically you have to put the continue before the stuff you want to skip.

FEM = [-16 16 -18 12 -6 6];
for i = 1:6-1
    if i ==3
        continue
    end
    FEM(i+1) + FEM(i) 
end

ans = 0

ans = -2

ans = 6

ans = 0

[Scott Banks]

Thannk you very much, Voss!

[Voss]

You're welcome!

Answer 2

[Torsten]

FEM = [-16 16 -18 12 -6 6];
n = numel(FEM);
for i = 1:n-3
    FEM(i+1) + FEM(i) 
end

ans = 0

ans = -2

ans = -6

FEM(end) + FEM(end-1)

ans = 0