Find in a matrix value pair.
3 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I have a matrix with 8 column and 250 raw. I need to create a function that read the first two column and and analyze the combination of this two value. For Example the matrix is
A|B|...
A|C|...
C|A|...
A|C|...
C|A|...
and I would like to have as output the single value pairs and the repetitions number . For example : A|B|1
A|C|2
C|A|2...
Could you help me please?
3 commentaires
Chandra Kurniawan
le 15 Déc 2011
I got little confused.
What does 'analyze the combination of this two value' means?
Can U tell me?
Réponse acceptée
Andrei Bobrov
le 19 Déc 2011
k = { 'bc' 'ec'
'ed' 'cd'
'dc' 'ec'
'bc' 'be'
'ed' 'cd'
'ed' 'ae'
'bc' 'ec'
'ba' 'bb'
'ca' 'aa'
'ab' 'ad'}
[a,c,c] = unique(k);
B = reshape(c,size(k));
[N,M,M] = unique(B,'rows');
p = histc(M,1:max(M));
out = [a(N),num2cell(p)];
2 commentaires
Fangjun Jiang
le 19 Déc 2011
+1. andrei, very nice way to use unique(CellArray,'rows') and avoid "Warning: 'rows' flag is ignored for cell arrays.". I used to combine cell array into char array and then apply unique().
Plus de réponses (1)
the cyclist
le 15 Déc 2011
I think I understand what you want to do. It can be done in three steps:
- Isolate the first two columns of your array:
>> x = A(:,[1 2]);
- Find the unique two-element combinations (i.e. unique rows):
>> [ux,i,j] = unique(x,'rows')
- Find the frequency count of the indices to those rows:
>> count = hist(j,unique(j))
I was not able to test this out, so you should think it through and test it, but I think those are the basic elements.
20 commentaires
the cyclist
le 19 Déc 2011
As I said in a prior comment, you have to download that function from here: http://www.mathworks.com/matlabcentral/fileexchange/25917-unique-rows-for-a-cell-array
Then put that function in your working directory, or somewhere in your path.
Voir également
Catégories
En savoir plus sur Logical dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!