How to modify vectors in a for loop?

I am trying to write some code that will average every two elements in a vector. However, when I run my program the vectors aren't changed. Is there some scope issue?

xData=ones(11,1)
yDataInner=ones(11,1)
yDataOuter=ones(11,1)
for i=[1,23]
    if mod(i,2)==0
        xData(i/2)=mean(V(i),V(i-1))
        yDataInner(i/2)=mean(sineInner(i),sineInner(i-1))
        yDataOuter(i/2)=mean(sineOuter(i),sineOuter(i-1))
    end
end

Answer 1

[per isakson]

Replace

for i=[1,23]

by

for i=1:23

and look up for in the documentation.

Your code will run the loop only for i==1 and i==23