I have a matrix with each column represents a feature over time. I need to find the moving average of these values with a given window size.
Is there a function like the one in MATLAB?
output = tsmovavg(vector, 's', lag, dim)
You can use the FILTER function. An example:
t = (0:.001:1)'; %#'
vector = sin(2*pi*t) + 0.2*randn(size(t)); %# time series
wndw = 10; %# sliding window size
output1 = filter(ones(wndw,1)/wndw, 1, vector); %# moving average
or even use the IMFILTER and FSPECIAL from the Image Package
output2 = imfilter(vector, fspecial('average', [wndw 1]));
One final option is using indexing (not recommended for very large vector)
%# get indices of each sliding window
idx = bsxfun(@plus, (1:wndw)', 0:length(vector)-wndw);
%'# compute average of each
output3 = mean(vector(idx),1);
Please note the difference in padding: output1(wndw:end)
corresponds to output3