Re: Surface Smoothing

*To*: mathgroup at smc.vnet.net*Subject*: [mg127621] Re: Surface Smoothing*From*: "Kevin J. McCann" <kjm at KevinMcCann.com>*Date*: Wed, 8 Aug 2012 03:15:04 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <jvo0fu$cfq$1@smc.vnet.net>

Any smoothing implicitly assumes that you "know" what the data should look like. So, I assume that you know that the spiky behavior is not "correct". Given that, how about a LSQ fit to some satisfactorily smooth function, e.g. a 2d polynomial or a truncated Fourier series? Kevin On 8/6/2012 4:50 AM, Nicholas Kormanik wrote: > This is a follow-up to a post I made last week (included at bottom). > > My ListPlot3D output is pretty spiky, with spikes extending above and below. > Quite hard to get a sense where any "sweet spots" might exist - > "neighborhood average" relatively high. > > I've looked into using the various forms of Interpolate. None of those will > "smooth the surface," as they all require passing through the original data > points. > > I'm wondering if any of you might know of a third-party Mathematica package > that will do surface smoothing? > > Please guide me to such package, if you do. Or if you know of another > approach that'll get the job done. > > Thanks, > > Nicholas > > > From: Nicholas Kormanik [mailto:nkormanik at gmail.com] > Sent: Friday, August 03, 2012 1:04 AM > To: 'mathgroup at smc.vnet.net' > Subject: ListContourPlot > > > > > > I've been attempting to create a contour plot within Mathematica 8.04. > > > > I posted to the Mathematica StackExchange, but didn't get a conclusive > answer: > > > > http://mathematica.stackexchange.com/questions/8821/creating-optimal-smoothe > d-contour-type-plots-x-y-z-using-mathematica-8-04 > > > > Hopefully someone here can assist. > > > > Here is a link to the data file: > > > > http://rapidgator.net/file/29594247/20201_23405_50502.XLS.html > > > > Here is a link to an example contour plot, made in another program (SAS): > > > > http://rapidgator.net/file/29594680/50502_20201_23405.png.html > > > > In case the files do not make it through to you, the data file is an Excel > .xls file with three columns, X,Y,Z. Z in the contour plot would be shown > by contours or a gradient of colors. > > > > If a contour plot isn't possible, perhaps ListPlot3D? > > > > The process is far from straight-forward. Definitely a learning curve > involved. > > > > Unfortunately the Mathematica documentation almost exclusively gives > examples using functions and distributions, not standard data columns for > input. > > > > Thanks, > > Nicholas Kormanik > > >