How can I (efficiently) compute a moving average of a vector?

Question

I\'ve got a vector and I want to calculate the moving average of it (using a window of width 5).

For instance, if the vector in question is [1,2,3,4,5,6,7,8]

Answer 1

Another possibility is to use cumsum. This approach probably requires fewer operations than conv does:

x = 1:8
n = 5;
cs = cumsum(x);
result = cs(n:end) - [0 cs(1:end-n)];

To save a little time, you can replace the last line by

%// clear result
result(1,numel(x)-n+1) = 0; %// hackish way to preallocate result
result(1) = cs(n);
result(2:end) = cs(n+1:end) - cs(1:end-n);