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Moving average type process


I wish to perform the following "moving average" type process on
a list to generate a new list:

Inputs:
  wtlist = {w1,w2,w3}     -- weight list
  inlist = {a,b,c,d,e,f}  -- any other list (>= 3 elements)

Output:
  outlist = {w1*a+w2*b+w3*c, w1*b+w2*c+w3*d, w1*c+w2*d+w3*e, w1*d+w2*e+w3*f}

Note, outlist will always contain 2 less (Length[wtlist]/2) elements
than in the input list (inlist).

If w1=w2=w3=x, then
the following works fine:

outlist = x*Drop[Plus@@NestList[RotateRight,inlist,2],2]

This is a weighted (from wtlist) sum over another list of arbitrary
length (inlist). I would like to get a "fast" function for doing this when
the weights are not equal.

-- Virgil




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