How to address multiple subfields of a structure at once?

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Hi all,
I have a simple programming question, which might be easy for some of you, but I just can’t find the answer: If I have multiple fields of a structure, how can I address the same variable of multiple subfields at once?
Here is an example:
x(1).a = 10;
x(2).a = 20;
x(3).a = 30;
Now I want a vector of all the a-subfields, like:
result = [10, 20, 30]
I was trying this, but it doesn’t work:
result = x(1:3).a;
Or I want to assign a different value to multiple a-subfields at once. I was trying this, but it doesn’t work:
x(1:3).a = 10;
I know that I can solve this in a for-loop, like:
for i = 1:length(x)
x(i).a = 10;
end
But is there a simpler solution without a loop for this problem?
Thanks!

Accepted Answer

KSSV
KSSV on 13 Oct 2016
Edited: KSSV on 13 Oct 2016
You can access the result like:
result = [x(1:3).a]
or
result = [x(:).a]
Replacing the fields I think loop is one option and other way is to use structfun. I tried to implement this but could not get it. Hope some one will answer it.
  1 Comment
Stephen23
Stephen23 on 13 Oct 2016
Matthias Stangl's "Answer" moved here:
Thats very good and super easy, thanks a lot! However, this only solved the question about "reading" of values. Is there also a similar solution to "write" values, as described in the second part of my question. Or do I actually need to solve this in a loop:
I want to assign a different value to multiple a-subfields at once. I was trying this, but it doesn’t work:
x(1:3).a = 10;
Thanks!

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More Answers (2)

Jan
Jan on 13 Oct 2016
[x(1:3).a] = deal(10);

Matthias Stangl
Matthias Stangl on 13 Oct 2016
Perfect, that's exactly what I needed! Many thanks to both of you!

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