MATLAB: Mean value of array

arraymean

I have one single dimension array containing doubles (A), and a 2 columns, x rows long   matrix containing positions that should be applied to the single dimensioned array(B).

what i want to do is: for each row in B the 1st column and the 2column should pick values from the A array and find the mean value of the two.

So far i've used

    for k=1:length(B)
    C(k) = mean([A(B(k,1)) A(B(k,2))])
    end

I wanted to go another way, withouth using the for loop.

somthing like:

C = mean([A(B(:,1)) A(B(:,2))])

but i dont succeed in doing it.

Do you have any sugestions?

Best Answer

Hi,

I think you forgot to specify the dimension. Try

C = mean([ A(B(:,1)), A(B(:,2))],2)

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