Iterating Through Multiple Structures in One Structure

I have a 1x1 structure that has 12 fields in it, which are all structures of varying sizes that all have the exact same fields inside of them.

What I want to do is iterate through all 12 structures in a for loop and do the same things to each of them. How would I do this? Do the field names have a "index" value or something similar that I can use to iterate through them? I haven't been able to find an answer online.

I also have all 12 structures seperate from each other, so if I need to iterate through them seperately I could do that, it seemed like the best way to do it was to put them all into one structure.

Answer 1

[Walter Roberson]

A = struct();
for K = 1 : 4
   ts = struct('pqr', randi(9, 1, 3), 'stu', randi(9, 1, 3))
   n = char(randi(0+['a', 'z'], 1, 5));
   A.(n) = ts;
end

ts = struct with fields:
    pqr: [5 9 8]
    stu: [6 1 4]

ts = struct with fields:
    pqr: [3 9 7]
    stu: [8 8 8]

ts = struct with fields:
    pqr: [5 5 6]
    stu: [6 7 2]

ts = struct with fields:
    pqr: [7 3 4]
    stu: [5 7 7]

A

A = struct with fields:
    zhanp: [1×1 struct]
    dqhtj: [1×1 struct]
    imnnu: [1×1 struct]
    bekzk: [1×1 struct]

structfun(@(S) [mean(S.pqr), sum(S.stu)], A, 'uniform', 0)

ans = struct with fields:
    zhanp: [7.3333 11]
    dqhtj: [6.3333 24]
    imnnu: [5.3333 15]
    bekzk: [4.6667 19]

[Spencer Ferris]

Thanks Walter! This looks like exactly what I want, quick follow-up question. I want to create plots of data in the structures. I created plots using your code and it looks like it did create the plots, but they are saved as 1 x 2 Line arrays, do you know how I'd go about getting those plots and exporting them as images?

[Walter Roberson]

If you are invoking plot() from within the structfun() then unless you are careful to create a new axes or figure each time, then the actual lines are likely to be deleted as soon as the next plot starts (unless you had "hold on").

I recommend making what you structfun() into a real function (not anonymous) that creates a figure and axes, plot()'s, creates appropriate annotations and legends, and print() or saveas() or exportgraphics().. and then deletes the figure.