[SOLVED ALREADY] Loop through data struct with variable names
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Hi, So it seems like I was able to solve it already so yeah, Imma post the solution as an answer for people to look into it in case they have a similar problem.
I am trying to loop through a structure called 'Erruptions'.
Now in this structure I have 3 more sub structs, thus it's length is 3.
The 3 structures have variable names 'E1', 'E2', etc. These are simply 1x2 doubles or vectors if you wanna call them that.
So by calling one of the structs I write
and I get its content
E1: [6.0014 1.0161]
E2: [4.5936 0.5191]
E3: [3.2693 0.2849]
E4: [2.7640 -0.0073]
E5: [2.3443 0.1345]
But when I want to get the number of elements it says it's only 1, doesn't matter if I use
length(Erruptions.sub_struct) % gives me ans = 1
size(Erruptions.sub_struct) % gives me ans = [1 1]
which is very confusing. I want to run a loop through every substruct but since it only recognizes them as one single element, opposed to the above shown 5, itleave the substruct after taking the first into consideration.
How can I solve this problem?
Voss on 14 Jul 2022
Edited: Voss on 14 Jul 2022
% creating a structure like yours
Erruptions = struct('sub_struct',struct( ...
'E1',[6.0014 1.0161], ...
'E2',[4.5936 0.5191], ...
'E3',[3.2693 0.2849], ...
'E4',[2.7640 -0.0073], ...
% Erruptions.sub_struct is a scalar structure, so its length is 1
% you want to get the fields of Erruptions.sub_struct
fn = fieldnames(Erruptions.sub_struct)
% and loop through those
for ii = 1:numel(fn)
More Answers (2)
Benjamin Thompson on 14 Jul 2022
You want to index into the structure array, then pass one of those array elements to the length function:
>> S1.E1 = [1 1];
>> S2.E1 = [1 1];
>> SArray(1) = S1
struct with fields:
E1: [1 1]
>> SArray(2) = S2
1×2 struct array with fields:
Error using length
Too many input arguments.