how to create a vector with the different sum of two elements of another vector?

Question

Enrica Brunetti 2019-3-17

评论： Stephen23 2019-3-18

v = [1, 2, 3, 4, 6, 8];
l = length(v)
for i = 1 : 2 : l (?)
    som = sum + v(i);
end

I don't know how to increse 'i' to create the sum of the two elements of the vector, the solution will be: som = [3, 7, 14]

Answer 1

Stephen23 2019-3-17

编辑：Stephen23 2019-3-18

No need to use a loop, some simple indexing works perfectly:

>> v = [1,2,3,4,6,8];
>> v(1:2:end)+v(2:2:end)
ans =
    3    7   14

or generalized slightly:

>> sum(reshape(v,2,[]),1)
ans =
    3    7   14

Enrica Brunetti 2019-3-18

Thank you.

And then if I want to create another vector with the average of two different elements of the same first vector, is there another general function?

The solution will be a = [ 5, 7]

Stephen23 2019-3-18

>> (reshape(v,2,[]),2)/2
ans =
   5
   7