How to count the number of the rank in each column of a matrix.

Load a rank matrix

1 2 3;

2 3 1;

2 1 3;

3 1 2;

1 3 2

How do I count the number of the rank in each column:

The desired output of counting matrix is as follows:

Rank First column Second column Third column

1 2 2 1

2 2 1 2

3 1 2 2

Thank you very much.

[Wan-Yi Chiu]

If I have a large matrix with 20 * 13 and each row with random rank from 1 to 13, how can I extend your command to my case? Thank you for help

[FannoFlow]

try this:

m = [
    1  2  3;
    2  3  1;
    2  1  3;
    3  1  2;
    1  3  2]

c = squeeze(sum(m == permute(unique(m),[3,1,2]), 1))

[Wan-Yi Chiu]

Thanks for your help.

For example, my matrix is as follows:

m = [1 2 3 4 5; 2 5 3 1 4; 2 1 3 5 4; 3 1 2 4 5; 5 4 1 3 2]

I need to count the ranks of each column and desire the output as follows:

Rank First column Second Third 4th 5th

1 1 time 2 1 1 0

2 2 times 1 1 0 1

3 1 0 3 1 0

4 0 1 0 2 2

5 1 1 0 1 2

Actually, my matrix will be 500 * 13 that each row is randomly from 1 to 13.

[FannoFlow]

ah I didn't realize unique returned a column vector. this should be what you need:

m = [1  2  3  4  5; 2  5  3  1 4; 2  1  3  5  4; 3  1  2  4  5;  5  4  1  3  2]

m = 5×5

1 2 3 4 5 2 5 3 1 4 2 1 3 5 4 3 1 2 4 5 5 4 1 3 2

u = unique(m);
T = array2table(squeeze(sum(m == permute(u,[3,2,1]), 1)), RowNames=string(u), VariableNames="Column " + (1:size(m,2)))

T = 5×5 table
         Column 1    Column 2    Column 3    Column 4    Column 5
         ________    ________    ________    ________    ________

    1       1           2           1           0           1    
    2       2           1           0           1           1    
    3       1           1           3           0           0    
    4       1           0           1           2           1    
    5       0           1           0           2           2    

[Wan-Yi Chiu]

Thanks again. However, the output is not correct for the matrix m. For example, the column 1 of T should be

1

2

1

0 (there is no 4)

1

Also, the column 2 should be

2

1

0 (there is no 3)

1

1

Also, the column 3 should be

1

1

3

0 (there is no 4)

0 (there is no 5)

Also, the column 4 should be

1

0 (there is no 2)

1

2

1

Also, the column 5 should be

0 (there is no 1)

1

0 (there is no 3)

2

2

[FannoFlow]

ah it appears the matrix needed to be transposed, thats all.

m = [1  2  3  4  5; 2  5  3  1 4; 2  1  3  5  4; 3  1  2  4  5;  5  4  1  3  2]

m = 5×5

1 2 3 4 5 2 5 3 1 4 2 1 3 5 4 3 1 2 4 5 5 4 1 3 2

u = unique(m);
T = array2table(squeeze(sum(m == permute(u,[3,2,1]), 1)).', RowNames=string(u), VariableNames="Column " + (1:size(m,2)))

T = 5×5 table
         Column 1    Column 2    Column 3    Column 4    Column 5
         ________    ________    ________    ________    ________

    1       1           2           1           1           0    
    2       2           1           1           0           1    
    3       1           0           3           1           0    
    4       0           1           0           2           2    
    5       1           1           0           1           2    

[Wan-Yi Chiu]

It works. Thank you very much.

Answer 1

[FannoFlow]

m = [
    1  2  3;
    2  3  1;
    2  1  3;
    3  1  2;
    1  3  2]

m = 5×3

1 2 3 2 3 1 2 1 3 3 1 2 1 3 2

c = squeeze(sum(m == permute(1:3,[3,1,2]), 1))

c = 3×3

2 2 1 2 1 2 1 2 2