AVERAGE OF EACH COLUMNS IN CELL

I have 'data' variable which is cell. I want to take the average of each column in 'data'. How can I take average of column in 'data' and subtract average from the 'data'?

Answer 1

[Image Analyst]

Try this (untested):

dataContents = data{1} % Extract array from a cell called data .  "data" was NOT called a cell array so I assume it's only one cell.
% Compute averages of columns
columnAverages = mean(dataContents, 1); % Average going down rows within columns.
% Subtract column average from each columns
[rows, columns] = size(dataContents);
% Expland to matrix the same size as the dataContents matrix.
columnAverages = repmat(columnAverages, [rows, 1]); % Legacy way of doing it that should work with older versions.
output = dataContents - columnAverages; % Do the subtraction

[Aybüke Ceren Duran]

In the line:

columnAverages = mean(dataContents, 1); % Average going down rows within columns.

It says:

Index in position 1 exceeds array bounds.

[Image Analyst]

Is it possible that you called your m-file "mean.m"? Or you have an array in your code called mean? I think that might cause the error. Otherwise, tell me what data is, or attach it in a mat file with the paper clip icon.

Answer 2

[Aybüke Ceren Duran]

I need the average of each column for PCA.

[Image Analyst]

To get the average of each column, use mean() on your matrix M:

averageOfColumns = mean(M, 1);