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How can i find cumulative mean inside a for loop?

Hey everyone,
I have a code which helps me to calculate the mean values. Each of the "cellList.meshData(j)" corresponds to a single column vector of values. I would like it to give me the total mean of all 25 cells. The following code gives me the mean for each cell.
for j=1:25
data=cellList.meshData(j);
if isempty(data{1,1})
continue
end
mean_int_val = mean(cellList.meshData{j}{1,1}.signal2);
end

  1 Comment

To imporve code-readability, I would not use 'continue' in this case:
for j = 1:25
data = cellList.meshData(j);
if ~isempty(data{1, 1})
mean_int_val = mean(cellList.meshData{j}{1, 1}.signal2);
end
end

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1 Answer

Answer by Nicolas B.
on 3 Sep 2019
Edited by Nicolas B.
on 3 Sep 2019
 Accepted Answer

Hi,
For your situation, you should consider that . So they are 2 situations:
  1. All vectors have the same size
  2. Vectors can have different sizes
If you are in the first situation, I would simply keep all mean_int_val and simply recompute the the mean of all means.
nData = 25;
mean_int_val = NaN(1, nData);
for j=1:nData
data=cellList.meshData(j);
if isempty(data{1,1})
continue
end
mean_int_val(j) = mean(cellList.meshData{j}{1,1}.signal2);
end
mean_total = mean(mean_int_val, 'omitnan');
If you are in the second situation, I would also keem the number of samples and then compute the mean.
nData = 25;
mean_int_val = NaN(1, nData);
mean_size = NaN(1, nData);
for j=1:nData
data=cellList.meshData(j);
if isempty(data{1,1})
continue
end
mean_int_val(j) = mean(cellList.meshData{j}{1,1}.signal2);
mean_size(j) = numel(cellList.meshData{j}{1,1}.signal2);
end
mean_total = sum(mean_int_val .* mean_size) / sum(mean_size);

  4 Comments

Show 1 older comment
This isn't the answer I was looking for. Maybe my question wasn't very clear, I apologize for that.
I would like my final output to be the mean of all 25 mean values. Your solution just gives me the individual mean values of the 25 cells.
Thanks for the comment. I corrected it with j instead of i (bad habits).
In my suggestions, the mean of all means is saved in mean_total variable.
Yes, I just tried the first solution out. It works for my purposes.
Thank you! :)

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