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Can someone elaborate on what a moving average system is?

I know that the system is defined as: $$y[n] = \frac{x[n] + x[n-1] + x[n-2]}{3}$$ How would we draw $y[n]$ given that we have a graph with discrete values for $x[n]$? Can someone actually draw a sample discrete time $x[n]$ graph and show how the corresponding $y[n]$ graph is generated?

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    Huh, wait. The form I'm accustomed to goes like $\dfrac{x_{n-1}+x_n+x_{n+1}}{3}$. The form you gave is the one usually used for endpoints... could you check your source again?2011-09-23
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    this is for a discrete time signal.... I am sure this is correct...2011-09-23
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    Anyway... you're already aware of the "sliding window" analogy, right? Say you have the sequence $(x_1,x_2,x_3,x_4,x_5,x_6,x_7)$. The first pass replaces $x_3$ with the mean of $x_1,x_2,x_3$. Then, you shift by one place, replacing $x_4$ with the mean of $x_2,x_3,x_4$, and so on, up until you're replacing $x_7$ with the mean of $x_5,x_6,x_7$. Note that the group of points being taken always has overlap with the previous one.2011-09-23
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    @Guesswhoitis. the OP is a causal filter, yours is not. the way to see how this works is to consider a sliding window of 3 samples and at each point, the output $y[n]$ is the mean of the previous 3 input samples $x[n],x[n-1],x[n-2]$ in the window2015-09-09
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    @oldrinb, that's why I provided the second comment; I know that there are a number of moving averages; I just mentioned the one I'm used to.2015-10-06

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