Sort the array by template
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Rostislav Teryaev
le 23 Mai 2018
Commenté : Ameer Hamza
le 23 Mai 2018
I have two arrays A1 and B1 in which elements correspond:
A1 = [a1 a2 a3 a4 a5];
B1 = [b1 b2 b3 b4 b5];
then I change order of elements of the first array anyhow (they are all unique), for exaple like this:
A2 = [a4 a1 a3 a5 a2];
The question is how to get array B2 sorted in the same way? It should be
B2 = [b4 b1 b3 b5 b2];
I tried to write function which is:
B2 = zeros(length(B1),1);
for i = 1:length(B2)
ind = find( A1 == A2(i) );
B2(i) = B1(ind);
end
but as it uses for loops speed is not fast. Maybe there is a way to do it by using MatLab builtin functions?
0 commentaires
Réponse acceptée
Ameer Hamza
le 23 Mai 2018
Modifié(e) : Ameer Hamza
le 23 Mai 2018
For a generalized matrix a1 and a2, you can use the following code
[~,index] = ismember(a2', a1', 'row');
b2 = b1(index)
This will work on R2016b and later.
8 commentaires
Ameer Hamza
le 23 Mai 2018
You will get hold of such solution once you start to develop some intuition about these frequently used MATLAB functions. Of course, that comes with time, experience and reading a lot of documentation :)
Plus de réponses (1)
sloppydisk
le 23 Mai 2018
a1 = [1 4 2 5 7];
b1 = 1:5;
mySecretOrder = [1 3 2 5 4];
a2 = a1(mySecretOrder);
[~, order] = ismember(a2, a1)
b1 = b1(order)
2 commentaires
Voir également
Catégories
En savoir plus sur Logical dans Help Center et File Exchange
Produits
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!