two dimension array mean and deviation calculation

Hi, I have a two dimension array like X = normrnd([1 4;2 2;3 6;4 4;5 7;6 4;7 9;8 4;9 8;10 4],1); and I want to calculate the mean and standard deviation after several rounds. For example, I want to generate the array for 5 times, and I'd like to see the mean and standard deviation of each element, how can I do that?

Many thanks!

Answer 1

[Mikhail]

There are a lot of ways to do that. I would generate 3D array, where the third dimension will be of the size = # of rounds (5);

So you will have array X(m,n,r), where r=1:5 (if number of rounds is 5).

Now, use mean and stddiv with second argument 3:

MeanX=mean(X,3); StddivX=stddiv(X,3);

This will calculate mean and stddiv through 3rd dimension. As a result you obtain two 2D arrays, what you were asking.

[Mikhail]

So X(:,:,1) is your first 2D array, X(:,:,5) - last, etc.

[wen]

thanks a lot!