How to match column of a one matrix with another column of second matrix?
2 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
I have three matrices like
A =
0 0 3
0 2 3
1 2 0
1 0 0
B =
0 3 0
2 3 0
2 0 1
0 0 1
C =
3 0 0
3 0 2
0 1 2
0 1 0
I want arrange matrix B and C like matrix A means column wise they all should like similar.
Could you please help me?
4 Commenti
John D'Errico
il 28 Nov 2021
So you are asking someone to show how to rearrange the columns of B and C, to match A? What if there is no exact rearrangement?
Risposta accettata
John D'Errico
il 28 Nov 2021
Modificato: John D'Errico
il 28 Nov 2021
A = [ 0 0 3
0 2 3
1 2 0
1 0 0];
B = [ 0 3 0
2 3 0
2 0 1
0 0 1];
C = [ 3 0 0
3 0 2
0 1 2
0 1 0];
If you will accept ONLY an exact rearrangement of the columns, then we might look for a permutation matrix. Does one exist?
PAB = (normalize(A,1,'norm',2)'*normalize(B,1,'norm',2)) > 1-10*eps
If the matrix PAB is a valid permutation matrix, then it will have exactly one unit element in every row and every column. Now we can transform B using the product:
B*PAB'
If you feel you really need to get the permutation vector itself, I could do this:
[~,pab] = max(PAB,[],2)
B(:,pab)
Similarly,
PAC = (normalize(A,1,'norm',2)'*normalize(C,1,'norm',2)) > 1-10*eps
C*PAC'
Now, suppose we have a matrix that fails to have an exact rearrangeent of the columns?
D = [ 3 0 0
0 2 3
1 2 0
1 0 0];
PAD = (normalize(A,1,'norm',2)'*normalize(D,1,'norm',2)) > 1-10*eps
No such permutation of the columns exists here. A simple test of that is:
sum(PAD,1)
sum(PAD,2)
Both such tests should result in vectors of purely ones if PAD were a permutation matrix.
3 Commenti
John D'Errico
il 30 Nov 2021
But that does not mean there is any valid EXACT rearrangment for what you ask. I don't see your data, since you have not provided the actual data. So I cannot show you why what you are asking to do seems to have failed.
When I did ask you what was intended if an exact solution to the column rearrangement problem does not exist, all you said was "yes". Does "yes" tell me anything of significance?
Più risposte (0)
Vedere anche
Categorie
Scopri di più su Resizing and Reshaping Matrices in Help Center e File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!