mean of nonzero elements which are in between zero elements in each column

I have matrix of 4097X1000. I want to take mean of nonzero elementmean of nonzero elements which are in between zero element in each column of matrix, like

A= 1 3 5 0 0

2 0 0 2 1

3 4 5 7 1

5 3 5 0 0

3 0 0 3 1

in Matrix A I have to take means of element inbetween zero i.e. in column 2 for 4 and 3, in column 3 for 5and 5, in column 4 for 2 and 7 which between zero.

Answer 1

[Deepak]

Hey @Harish Kumawat,

You can compute the mean of non-zero elements between 0s in each column of a matrix and store them with the following method:

% Example matrix
myMatrix = [1 3 5 0 0; 2 0 0 2 1;  3 4 5 7 1;  5 3 5 0 0; 3 0 0 3 1];

% Initialize the array to store column means
columnMeans = zeros(1, size(myMatrix, 2));

% Loop through each column
for col = 1:size(myMatrix, 2)
    
    % Find the indices where 0 appears in the current column
    zeroIndices = find(myMatrix(:, col) == 0);
      
    if(size(zeroIndices) < 2)
        columnMeans(col) = 0;
    else
        first = zeroIndices(1);
        last = zeroIndices(end);
        
        sum = 0;
        cnt = 0;
        for row = first:last
            if(myMatrix(row , col) > 0)
                sum = sum + myMatrix(row , col);
                cnt = cnt + 1;
            end
        end
        
        columnMeans(col) = sum/cnt;
    end
end

% Display the column means
disp(columnMeans);