MATLAB: Averaging sequential data if values are the same

Question

I want to be able to average the values of an array of n rows and 5 columns, based on the repeated values of a specific column.

I only want to average the values that are next to each other and not all that repeat. Such that:

%Original data:
key_column = [-6 -6 -6 -6 -5 -5 -3 -3 -3 -1 -1 -1 0 0  1 1 2 2 2 3 3 5 5 5 5 6 6 6 6 4 4 4 3 3 3 3 3 3 3 2 2 2 1 1 1 1 0 0 -1 -1 -2 -3 -5 -5 -5 -5 -5 -5 -5 -6 -6 -6];
%Ends up as:
key_column_avg = [-6 -5 -3 -1 -0 1 2 3 5 6 4 3 2 1 0 -1 -2 -3 -5 -6]

I'm running into trouble because the values of the repeated numbers appear at multiple points in the column and I only want the to be averaged if they are "next to each other" on the column. Also, I'm having issues because the number of repeated values isn't the same for each number. Sometimes the value repeats for 10 times, sometimes for 3, sometimes for 7, sometimes for 4.

Is it possible to do this?

Thank you.

Answer 1

key_column_avg = key_column(diff([0,key_column(:)'],1,2) ~= 0);