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Re: nth differences


Hi,

NthDifference[lst_List, n_Integer] := 
  Nest[Drop[# - RotateRight[#], 1] &, lst, n]

and

lst = {1, 2, 5, 7, 8, 9};

Table[NthDifference[lst, i], {i, 1, 3}]

gives

{{1, 3, 2, 1, 1}, {2, -1, -1, 0}, {-3, 0, 1}}

Regards
  Jens


Zachary Turner wrote:
> 
> Say I have a list of k integers and I want to produce a list containing the
> first differences?  For example, given {1, 2, 5, 7, 8, 9} the first
> differences are {1, 3, 2, 1, 1}, and the second differences are {2, -1, -1,
> 0}, the third are {-3, 0, 1}, etc


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