How do I loop through a structure field which contains multiple arrays?

Hi all,

I have a big structure which contains different substructures.

The structure is called 'subjects' and contains information for each subject.

However, I am interested in angles, which are located in subjects.sessions.trials(1).data.angles.

subjects.sessions.trials(1).data.angles contains 28 fields, all being a 1289x1 double, which all have names of different angles.

I want to plot the 28 angles by looping through, but I cannot manage to select what I need in the for loop:

for i = 1:NSessions
    figure();
    plot(subjects.sessions.trials(i).data.angles. ......);
end    

Attached is a snapshot of what the structure field looks like.

I tried creating a cell array with the 28 names and then use

for i = 1:NSessions
    for k = 1:NAngleName
        figure();
        plot(subjects.sessions.trials(i).data.angles.AngleName{k});
    end
end

But this is not working.

Thanks in advance.

[KSSV]

Read about getfields and getfieldnames.

[Inti Vanmechelen]

Thank you for your response KSSV.

I did read about getfields, but using 'getfields' still gives me 1x1 struct containing 28 fields which are all 1289x1 doubles. And it is those 1289x1 doubles which I would like to select, which is currently not workin out.

Answer 1

[Daniele Mascali]

If you want to make your last attempt work, you might use eval:

eval(['plot(subjects.sessions.trials(i).data.angles.',AngleName{k},');']);

[madhan ravi]

Eval is not necessary here!

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

[Daniele Mascali]

You are right.

However, I was not aware of Dynamic Field References. One very simple solution is

plot(subjects.sessions.trials(i).data.angles.(AngleName{k}));

Thanks for the link!!

[Inti Vanmechelen]

I figured that out myself about 10 seconds before your reply :)

Thanks!