w = bartlett(L) returns an L-point
Bartlett window in the column vector w, where L must be a positive integer. The coefficients of a Bartlett
window are computed as follows:
The window length .
The Bartlett window is very similar to a triangular window as
returned by the triang function.
The Bartlett window always has zeros at the first and last samples,
however, while the triangular window is nonzero at those points. For L odd,
the center L - 2 points of bartlett(L) are
equivalent to triang(L-2).
If you specify a one-point window (set L = 1),
the value 1 is returned.