MATLAB: Identify duplicate entries of matrix and delete

Question

Hello,

I have an array as follows. I need to identify duplicate row values from column 1 to 5 and delete the row with negative 7th column element and keep the other row. For example, here row values 5 and 6:

1973  4  1  13  1,34  1,31  0,95  0,35
1973  4  2  2  1,17  1,14  0,85  0,29
1973  4  2  8  -0,5  -0,53  -0,81  0,28
1973  4  2  15  1,54  1,51  1,03  0,48
1973  4  2  18  1,82  1,79  1,03  0,76
1973  4  2  18  1,82  1,79  -0,54  2,33
1973  4  3  3  2,24  2,21  1,02  1,19
1973  4  3  15  1,73  1,70  1,15  0,54

The resulting matrix

1973  4  1  13  1,34  1,31  0,95  0,35
1973  4  2  2  1,17  1,14  0,85  0,29
1973  4  2  8  -0,5  -0,53  -0,81  0,28
1973  4  2  15  1,54  1,51  1,03  0,48
1973  4  2  18  1,82  1,79  1,03  0,76
1973  4  3  3  2,24  2,21  1,02  1,19
1973  4  3  15  1,73  1,70  1,15  0,54

Any help?

Answer 1

Assigning your matrix to variable ‘M’, this should do what you want:

[~,idx] = unique(M(:,1:5), 'rows', 'stable');
Result = M(idx,:);