How to compile the average values of a variable in .mat files

I have 81 .mat files that correspond to the years 1930 to 2010 and each contain a variable named 'zdaily'. In each zdaily, there are is a matrix that is 240x121x366or365 depending on if that year was a leap year or not. I'm trying to create a 'for loop' that will not only compile the .mat files into one large matrix but also take the average over the time dimension so that instead of 81x365or366, it will just be 81. Thanks

[Giridharan Kumaravelu]

average = zeros(81,1); 
for i = 1:81
      data = matfile("filenameOfyear1930+i.mat");
      average(i) = mean(data.zdaily,3);
end

Is this what you wanted?

[Paul Torres]

This would be close but does it account for leap years?

Answer 1

[Adam Danz]

Let's say your mat file is called 'myMatFile.mat' and the variable of interest is 'zdaily'.

% Pull data from file
filename = 'C:\Users\me\Documents\MATLAB\myMatFile.mat'; 
data = matfile(filename); 
zdaily = data.zdaily; 

% Average over the 2nd dim
m = mean(zdaily ,2); 

% Check size 
size(m) %should be [1,81]

The same thing with less lines of code (faster & cleaner)

data = matfile('C:\Users\me\Documents\MATLAB\myMatFile.mat'); 
m = mean(matfile.zdaily,2);

[Paul Torres]

There are 81 different .mat files, this code would only work for one, right?

[Adam Danz]

Yes, you'd need to implement a loop as Giridharan demonstrated in the comments section above. For example, you could create a cell array of all your filenames and loop through each element of the cell array.