Add large amount of variables

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Hello, I have a set of variables which are all Matrixes and their name is usually "Hsig_day_time". I would like to add them all but it there are about 120 and possibly there will be more than 1000.
Is there a way to add them all without writting each variable name in a line?
Stephen23 on 9 May 2022
"I am not sure if it is possible to load them as a struct. At least I can't do it."

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Accepted Answer

dpb on 9 May 2022
OK, I'll just make another Answer so previous conversation doesn't distract
Brute force; may be something a little more clever possible, but...
S=load('IBERIA.mat','-regexp', '^Hsig'); % load the variables beginning with Hsig only
C=struct2cell(S); % turn the fields into cells in cell array
A=C{1}; % begin accumulator for sum
for i=2:numel(C) % and iterate over the size of C
A=A+C{i}; % sum each array
mnA=A/numel(C); % compute mean
Above doesn't deal with NaN -- I noticed there are at least some matrices with NaN in them; I didn't search for which or where. I did note that the first 10 locations in both directions are finite.
You'll know better what to do with those locations...

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More Answers (1)

dpb on 9 May 2022
Edited: dpb on 9 May 2022
Don't try to explain in words; show us precisely what the external software generates.
" They are all inside a .mat file..."
Then at a minimum show us what
whos -file TheFileName.mat
returns for one of these files.
Even better would be to attach one here..."help us help you"
The initial (following) was written before I saw the above comment so presumed each was a separate file.
If they are 2D arrays and the dimensions are not humongous for each, then you can simply read each into a 3D array where each file is a plane and use mean(A,3)
If the total won't fit in memory, then a mean is simply a sum which can be computed as a running summation with only one file at a time, then divide the sum by the total number of files.
Either is a basically trivial task to iterate over all files in a particular location.
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Magnus Schneider
Magnus Schneider on 9 May 2022
I am sorry this is the first time I am posting here. The file is in the attachment. The final objective is to obtain a Matrix with the averages of each element of the Hsig matrixes. In the real examples there will be hundreds of Hsig matrixes...

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