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Creating a struct with means and standard deviations

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I'd like to create a script that loops through multiple subjects and creates a new structure with doubles in it.
First Column of Master Table: I want the SubjectID but I only want it once, I don't want it repeating like it is in the dataset I've attached.
Second Column of Master Table: I want it to lead to a struct with the means of each of the six events. So in the new struct, I want the first column of the first row to be for event 1_a, second column first row event 2_a, etc.
Third Column of Master Table: I want it to lead to a struct with the standard deviation of each of the six events.
Here's an example of what I want it to look like:
The examples of mean and standard deviation doubles are only for one subject. I'd like to loop this for every subject in the data table to create a master struct.

Accepted Answer

Chris on 16 Sep 2022
Edited: Chris on 16 Sep 2022
It looks like you want an array of structs. Use strings or uint64 for the IDs
S = struct('id',uint64(123456),'mean',rand(3),'stdev',rand(1,3))
S = struct with fields:
id: 123456 mean: [3×3 double] stdev: [0.7411 0.1904 0.5026]
% Add new data
for idx = 2:4
S(idx).mean = rand(3);
S(idx).stdev = rand(1,3);
S(idx).id = uint64(randi(1e9));
S = 1×4 struct array with fields:
id mean stdev
% Retrieve data
x = S(3).stdev
x = 1×3
0.6080 0.0728 0.3028
y = [S(1:2).id]
y = 1×2
123456 614065544
Chris on 16 Sep 2022
Edited: Chris on 16 Sep 2022
Unstack sounds useful, but I'm unfamiliar with it and man, I need to learn some table stuff.
@BA How about something like this?
EventData = readtable('Event_1_2.xlsx');
vars = T.Properties.VariableNames;
[u,~,ic] = unique(EventData.UserID);
for idx = 1:numel(u)
Updating(idx).ID = u(idx);
T = EventData(ic==idx,2:end);
Updating(idx).stdev = array2table(std(T{:,:}),'VariableNames',vars);
Updating(idx).mean = array2table(mean(T{:,:}),'VariableNames',vars);
BA on 16 Sep 2022
Thank you! That works. Appreciate you for helping me out!

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