Sum per 2 elements in vector

Hello,

I am trying to sum my vector by 2 elements.

An example:

I have:

A= [1;2;3;4;5;6]

What I want:

A_new = [3;7;11]

Is there any way to easily code this?

I know one way via a for-loop but I was wondering if there was a more efficient way.

Thanks in advance!

Answer 1

[Stephen23]

A = [1;2;3;4;5;6];
B = A(1:2:end) + A(2:2:end)

B = 3×1

3 7 11

or more generally:

B = sum(reshape(A,2,[]),1).'

B = 3×1

3 7 11

or

B = reshape(A,2,[]).' * ones(2,1)

B = 3×1

3 7 11

or

B = cellfun(@sum,mat2cell(A,2*ones(1,3),1))

B = 3×1

3 7 11

[Ann-Lara Aernoudts]

Perfect, that works!

I'll use the more general code.

Thank you!

Answer 2

[Abdel]

The sum of the last two elements in (call the result ans6)