indexing
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
hi,
how do i replace all the members of an array with with anoda set of arrays.. for example
a = [ q1 q2 q3 q4]
b = [1 2 3 4 2 4 3 1 2 1 3 4 3 2 1 2 3 4 1 3 2 4]
how do i replace the members of a with where q1=1, q2=2, q3=3 and q4=4 pls i will appreciate any help i can get for this.
thanks in advance
4 commentaires
Dr. Seis
le 15 Nov 2011
Ah, then use my last suggestion if you are using the elements in b for indexing.
Réponse acceptée
Dr. Seis
le 15 Nov 2011
Are you trying to create a row vector with all the different combinations of q1, q2, q3, and q4?
If so:
q1=11; q2=22; q3=33; q4=44;
a = [q1 q2 q3 q4];
b = reshape(a(perms(1:length(a)))',[1,numel(perms(1:length(a)))]);
If you would rather have a matrix of the different combinations, then:
b = a(perms(1:length(a)));
Or, if the order of b is really as you describe above, then use b as indices to a:
b = [1 2 3 4 2 4 3 1 2 1 3 4 3 2 1 2 3 4 1 3 2 4];
c = a(b);
2 commentaires
Dr. Seis
le 15 Nov 2011
Yeah, I changed it just to demonstrate that the elements in a do not necessarily need to be 1:4, but the indexing needs to be 1:length(a) in order to do any rearranging they may want to do. I, too, do not understand fully... just a few guesses.
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Matrix Indexing 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!