Re: nth differences

*To*: mathgroup at smc.vnet.net*Subject*: [mg39877] Re: nth differences*From*: Daniel Reeves <dreeves at umich.edu>*Date*: Sun, 9 Mar 2003 05:30:22 -0500 (EST)*Organization*: University of Michigan Engineering*References*: <b4c9lo$nqg$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

difs[x_] := (#2-#1&) @@@ Partition[x, 2, 1] For the nth differences, you can do Nest[difs, x, n] --- \/ FROM Zachary Turner AT 03.03.08 08:29 (Today) \/ --- > 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 -- Daniel Reeves -- http://ai.eecs.umich.edu/people/dreeves/ Mathematicians do it continuously and discretely. -- bumper sticker by Robert L Dawes