A concise way to sort the rows of matrix A in the same order of the rows of matrix B

Hi, do you know a way to sort the rows of matrix A in the same order of the rows of matrix B, but in a more concise way/code as I did (e.g. without a loop for)?

P.S.: bear in mind that (i) only the first two columns of A are used for the sorting, and that (ii) sometimes elements of the first two columns of A are switched when compared to B (i.e. in a certain row, the number in the first column, in A, is the number in the second column, in B, and viceversa), e.g. "6128 2269" in A corresponds to "2269 6128" in B.

A = [   3358        6128           0           0          30          37          42          30
        5945        6128          21          21          36          42          49          35
        5945        7505           0           0          31          37          41          30
        6128        2269          20          20          34          41          47          33
        7120        2269          26          25          42          51          58          42];

B = [   2269        6128
        2269        7120
        3358        6128
        5945        6128
        5945        7505];
    
[~,id1] = ismember(A(:,[1 2]),B,'rows');
[~,id2] = ismember(A(:,[2 1]),B,'rows');
id3 = [id1 id2];
for i = 1 : size(B,1)
    [id4,~] = find(id3==i);
    C(i,:) = A(id4,:);
end


% result
C =
        6128        2269          20          20          34          41          47          33
        7120        2269          26          25          42          51          58          42
        3358        6128           0           0          30          37          42          30
        5945        6128          21          21          36          42          49          35
        5945        7505           0           0          31          37          41          30

Answer 1

[Cris LaPierre]

I think you have a good approach considering that any permutation of the 2 columns is considered equal. However, you can just use indexing to create C. No need to loop through everything.

Another option might be to sum the two columns of A and B, but that isn't any more succinct.

A = [   3358        6128           0           0          30          37          42          30
        5945        6128          21          21          36          42          49          35
        5945        7505           0           0          31          37          41          30
        6128        2269          20          20          34          41          47          33
        7120        2269          26          25          42          51          58          42];

B = [   2269        6128
        2269        7120
        3358        6128
        5945        6128
        5945        7505];
    
[~,id1] = ismember(B,A(:,[1 2]),'rows');
[~,id2] = ismember(B,A(:,[2 1]),'rows');
id3 = id1+id2;

id3 = 5×1

4 5 1 2 3

C = A(id3,:)

C = 5×8

6128 2269 20 20 34 41 47 33 7120 2269 26 25 42 51 58 42 3358 6128 0 0 30 37 42 30 5945 6128 21 21 36 42 49 35 5945 7505 0 0 31 37 41 30

[Sim]

Cool, thanks a lot @Cris LaPierre! This is much better! :)