Access data in a structure using a loop
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hi, I have a structure (str) with several files (file_1, file_2...). There is a variable (xt) I'd like to retrieve for each file, and save all the variables in 'a'.
For example, a{2,3} would contain the following information from the structure: a{2,3} = str.file_2.xt(3,:); I'd like to do this in a for loop to get a{ii,jj}, where ii=1:7 (file_ii) and jj=1:30 (xt(jj,:))
Can I get some help? Thanks
0 commentaires
Réponse acceptée
Stephen23
le 7 Mar 2017
Modifié(e) : Stephen23
le 7 Mar 2017
Best Solution: non-scalar structure
Your code would be a lot simpler if you used a non-scalar structure rather than dynamically accessing fieldnames like that. Then your task would be trivial to solve:
>> str(1).xt = [0,1;2,3;4,5];
>> str(2).xt = [6,7;8,9;10,11];
>> str(3).xt = [12,13;14,15;16,17]
>> out = num2cell(cat(3,str.xt),2);
>> out = permute(out,[3,1,2]);
and checking the output:
>> out{2,3}
ans =
10 11
Complicated Solution: dynamic fieldnames
If you insist on making your code more complicated than it needs to be, then you could try doing this:
str.file_1.xt = [0,1;2,3;4,5];
str.file_2.xt = [6,7;8,9;10,11];
str.file_3.xt = [12,13;14,15;16,17];
out = struct2cell(str);
out = [out{:}];
out = num2cell(cat(3,out.xt),2);
out = num2cell(out,2);
out = permute(out,[3,1,2]);
Note that the first two lines convert your nested structures into one non-scalar structure, thus making this answer just like the first one except more complicated. You would be better off storing your data in a non-scalar structure to start with (or perhaps an even simpler data variable, e.g. an ND numeric array).
0 commentaires
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Structures 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!