滑動平均
filter
windowSize = 5;
b = (1/windowSize)*ones(1,windowSize);
a = 1;
y = filter(b,a,x);
y(1) is equivalent to 0.2*x(1).
y(2) is equivalent to 0.2*(x(1)+x(2)).
...
y(5) is equivalent to 0.2*(sum(x(1:5)) = mean(x(1:5)).
y(6) is equivalent to mean(x(2:6)).
...
y(100) is equivalent to mean(x(96:100)).
