Taking an average of every n elements of one column

Hi I have a 144x73x551 array. I want to take the average of every 12 elements in the third column into a new array. What is the best way to go about it? Thanks!

Answer 1

[David Goodmanson]

Hi Tony,

a = rand(144,73,551);     
b = squeeze(a(:,3,:));             % take all the third columns
c = mean(reshape(b,12,[]));        % reshape them into 12-row columns, take the mean
d = reshape(c,144/12,[]);          % put the 12 means down each new column, 551 columns

Taking every third column reduces the 3d array to a 2d array. The result is a set of means down each new column, with the old index down the third dimension being the column index of the new array.