MATLAB: Enlarge vector by putting average of surrounding numbers in between of every number of original vector

Question

How to make a longer vector by adding an additional element between neighboring elements in the original vector. Each new element should equal the average of its neighboring elements. x = [0 2 3 2 1 -1]

Answer 1

x(3:2:2*numel(x)-1)=x(2:end);
for i=2:2:numel(x)-1
x(i)=(x(i-1)+x(i+1))/2
end