How can I use cycle in structures?

Hi all, Well I have structure that contains multiple variables for example

    % code
a.a=1;
a.b=2;
a.c=3;
a.d=4;
a.e=5;
a.f=6;
 etc...

The problem is that I want to call the third variable of a structure without calling its name for example in such way a.(3) but it does not work, so my idea is to use for loot for it but I do not know how to use it. Any ideas would be a great job for me.

Answer 1

[Guillaume]

If the fields of the structure have no meaning and only their order is important, then you shouldn't be using structures. If all you're storing in your fields are scalars, then a matrix would be better, otherwise a cell array. Using structure fields for that is just as bad as using dynamically generated variable names.

So, assuming you're not using the structure as a structure, I'd convert it to a cell array with struct2cell and then optionally to a matrix with cell2mat:

c = struct2cell(a);
%accessing the 3rd variable is then:
var3 = c{3};

%if all values are scalar, then:
m = cell2mat(c);
var3 = m(3);

Otherwise, the answer to your question is to use fieldnames and dynamic field names:

fn = fieldnames(a);
var3 = a.(fn{3});

[Giorgi]

Thank you for your response I used fieldnames and it works fine :)