MATLAB: How to find the average of all rows across a series of columns

average

I am fairly new to Matlab so I'm sorry if this seems super obvious…

Have a matrix of 1000 rows, and 10 columns. How do I find the average across all the rows, and then save that column of averages into a new matrix? (this is in a loop)

EMGmatrix(:,j-1) = EMG_new; Average = mean(EMGmatrix(:,:);

Thanks!

Best Answer

You do not need a loop for this. Consider the following case:

 A=randi([1 4],1000,10);%demo data
 res=mean(A,2);

res variable contains the average of each row, which is 1000x1.

Related Solutions

MATLAB: Average each block of class in a matrix

It's unclear how your input data is actually stored in matlab so please clarify if the below doesn't apply.

I'm assuming that you have a two column matrix with one column storing the the class and the other the column storing the values you want to average by class. In this case, this is trivially achieved with groupsummary:

classcolumn = 1;  %change as appropriate
valuecolumn = 2;  %can be more than one column. Each column will be average by class
classmean = groupsummary(yourmatrix, classcolumn, 'mean', valuecolumn);

Other simple ways this can be achieved: splitapply or accumarray:

classcolumn = 1;
valuecolumn = 2; 
group = findgroups(yourmatrix(:, classcolumn));
classmean = splitapply(@mean, yourmatrix(:, valuecolumn), group);
%or
classmean = accumarray(group, yourmatrix(:, valuecolumn), [], @mean);  %this one can only work on one column though

MATLAB: Hi everyone! I need your help.

Adapt this into your problem:

A=randi([1 5],194,201,360);
B=randi([1 5],194,201,30);
for i=120:270
    A(:,:,i)./B(:,:,1:30);
end

Best Answer

Related Solutions

MATLAB: Average each block of class in a matrix

MATLAB: Hi everyone! I need your help.

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