Re: Correlation function and data

*To*: mathgroup at smc.vnet.net*Subject*: [mg24748] Re: Correlation function and data*From*: "Deborah Leddon " <Dleddon at students.cas.unt.edu>*Date*: Wed, 9 Aug 2000 02:31:56 -0400 (EDT)*Organization*: University of North Texas*Sender*: owner-wri-mathgroup at wolfram.com

Hello, I am trying to construct an autocorrelation function that can be applied to a data set as follows; n=Length[data]; c[y_]:= Sum[(data[[i]] - Mean[data] )* ( data[[i+y]] - Mean[data])/ Variance[data], {i,1,n - y}]; corrfunction = Array[c, {n - 1}]; ListPlot[corrfunction, PlotJoined->True] Problem is , this routine works well for data sets up to a length of 300 points, but gets unusually long for larger data sets , say around 1000-3000 points in length. I've tried "Map" (using anonymous function rules), Table-Evaluate, etc.. Anyone got any ideas? I would much appreciate them! Regards, Deb L.

**Follow-Ups**:**Re: Re: Correlation function and data***From:*Daniel Lichtblau <danl@wolfram.com>