take the average of each column element of two rows (in a 2 dimensional array) and insert that average between the two rows

I'm trying to take the average of 2 row elements in a 2 dimensional array and insert that average between the two.

For example,with the array:

2,3,4

4,5,6

should result in:

2,3,4

3,4,5

4,5,6

[Wayne King]

you don't say what you want to happen next, so do you want the average of rows 1 and 2, then 3 and 4, then 5 and 6...

Or do you want the average of rows 1 and 2, 2 and 3, 3 and 4...

[Allan N]

Thank you for the fast response. I was planning to do this iteratively; so I'm wanting to put this routine in a IF loop, so that in the next go around, the average of rows 1 and 2 will be inserted between rows 1 and 2, and the average of rows 2 and 3 will be inserted between these 2 rows. And so on until the criteria is reached. Wich will do what I want? Wayne's or Andrei's?

[Allan N]

So something like:

DO n1=1:repeat_until_necessary

   DO n2=1:max_row_size

      IF criteria_not_met

        take_average_and_insert
      end
  end
end
I'd appreciate any help! Thank you!!

Answer 1

[Andrei Bobrov]

out = sort([mean(x);x])

[Image Analyst]

Works for that one case but won't work in general. Try it for this matrix:

m=[12,13,44;...
4,5,6]

Answer 2

[dpb]

The specific answer could be

x=[x(1,:);mean(x);x(2,:)];

As Wayne points out, you've not provided sufficient info to know precisely how to generalize to a more generic solution.

Answer 3

[Image Analyst]

If you have the Image Processing Toolbox, you can simply use resize():

m=[2,3,4;...
4,5,6]
[rows, columns] = size(m); % Find out the size of m first.
% Insert mean rows.
out = imresize(m, [2*rows - 1, columns], 'bilinear')