How to find average of all maltab files in folder and write avrage of each file in single excel file.

Hi All,

I am new on maltab scripting, I have 100+ maltab files and all files having same structure. Maltab file containing only one single column and rows count will differ for each file, I need to find average of the each file and write into one excel file. Is possible to write average of file with file name in excel? I have tried below code but it having some error. Cloud please help me to achieve this requirement.

Thanks a lot!!

folder   = 'D:\Your\Folder\'; % Give the folder path
matFiles = dir(fullfile(folder, '*.mat'));  % Use absolute path names
numfiles = length(matFiles);
average  = zeros(1, numfiles);
for k = 1:numfiles
  M          = load(folder(k).name);
  average(k) = mean(M(:,1));
end
csvwrite(fullfile(folder, 'Avg_matFiles.csv'), average);

[Guillaume]

If you get an error then give us the full text of the error message so we can understand what is going wrong.

If you load a mat file, typically you get a structure whose fields are the names of the variables inside the mat file. You only get a matrix if the file is a text file. Are you sure that M is a matrix?

[Sameer Pathan]

Below error i am getting and i could not understant what's the mean of this,

>>aap

struct contents reference from a non-struct array object.

Error in aap (line 6)

M = load(folder(k).name);

Answer 1

[Bob Thompson]

You are receiving that error because you are trying to load the directory string, not the file.

M = load(matFiles(k).name);

[Alex Mcaulley]

And as Guillaume said:

average(k) = mean(M(:,1));

should be

average(k) = mean(M.M(:,1));

[Sameer Pathan]

Thank you so much!! and how to save avg of each file with file name? is it possible?

[Bob Thompson]

Yes, it is definitely possible. You already have average(k) as your result. Because you are looking to just save a .mat file with both, then I would suggest something like this inside the loop.

[results(k).name] = matFiles(k).name;
[results(k).average] = mean(M.M(:,1));

It is a bit of a reorganization, but when you do go to save the information you can just save the results variable.

save('Averages.mat','results');

[Sameer Pathan]

It looks like some thing this,

folder = 'D:\Your\Folder\'; % Give the folder path

matFiles = dir(fullfile(folder, '*.mat')); % Use absolute path names

numfiles = length(matFiles);

average = zeros(1, numfiles);

for k = 1:numfiles

[results(k).name] = matFiles(k).name;

[results(k).average] = mean(M.M(:,1));

end

csvwrite(fullfile(folder, 'Avg_matFiles.csv'), results);

Am I correct?

[Bob Thompson]

I apologize, I forgot that you were just wanting to write to a .csv file. In that case the best way to do strings and data is to do a table. You can use your original average(k) method as well.

folder   = 'D:\Your\Folder\'; % Give the folder path
matFiles = dir(fullfile(folder, '*.mat'));  % Use absolute path names
numfiles = length(matFiles);
average  = zeros(1, numfiles);
for k = 1:numfiles
  average(k) = mean(M.M(:,1));
end
results = table('Name',[matFiles.name],'Average',average)
writetable(results,fullfile(folder, 'Avg_matFiles.csv'));

I am specifically switching to writetable instead of csvwrite, because csvwrite only works with numeric data, while writetable is not limited in such a manner.

Answer 2

[Sameer Pathan]

Thanks a lot, you are the superb!!!