MATLAB: How to quickly find the maximum group of same rows in a matrix

matrix

Dear All,
I have a matrix and there exist identical rows in the matrix. I want to find the maximum group of identical rows in this matrix. For example, I have a matrix as follows:
A = [0 1 0 1 0 0 0 0; 1 0 0 0 1 0 0 0; 1 0 0 0 1 0 0 0; 1 1 0 0 0 0 0 0; 0 0 1 0 0 0 0 1; 0 0 0 0 0 1 1 0; 0 1 0 1 0 0 0 0; 0 1 0 1 0 0 0 0].
There are two groups of identical rows: {row 1, row 7 and row 8}, {row 2, row 3}. So the answer is {row 1, row 7, row 8}. But how can I quickly find it?
Best regsards,
Benson

Best Answer

Try this: 
A = [0     1     0     1     0     0     0     0; 1     0     0     0     1     0     0     0; 1     0     0     0     1     0     0     0; 1     1     0     0     0     0     0     0;  0     0     1     0     0     0     0     1;  0     0     0     0     0     1     1     0;  0     1     0     1     0     0     0     0;  0     1     0     1     0     0     0     0];
[Au,~,idx] = unique(A, 'rows');
tally = accumarray(idx, 1);
Out = A(idx == max(tally),:)                                % The Rows Themselves
RowIdx = find(idx == max(tally))                            % The Row Indices
producing: 
RowIdx =
     1
     7
     8
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