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Re: dark halo around gaussian peak in Plot3D?

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  • Subject: [mg130111] Re: dark halo around gaussian peak in Plot3D?
  • From: "Michael B. Heaney" <mheaney at alum.mit.edu>
  • Date: Sun, 10 Mar 2013 00:49:03 -0500 (EST)
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That makes the plots look perfect, thanks!

On Sat, Mar 9, 2013 at 2:27 AM, djmpark <djmpark at comcast.net> wrote:

> Michael,
>
> It looks to me like a numeric problem with very small numbers.  You can
> work
> around it by clipping the function. Here I also scaled up the function by
> 100 just to get a convenient range.
>
> Plot3D[100 Clip[
>    PDF[BinormalDistribution[0], {x, y}], {10^-150, 20}], {x, -40,
>   40}, {y, -40, 40},
>  PlotRange -> All,
>  PlotPoints -> 30,
>  Mesh -> None]
>
> If you decrease the lower Clip value by much you will get the "dark halo"
> back. It seems to be associated with the front FaceForm losing its color.
>
> Plot3D[100 Clip[
>    PDF[BinormalDistribution[0], {x, y}], {10^-200, 20}], {x, -40,
>   40}, {y, -40, 40},
>  PlotStyle -> Directive[FaceForm[Gray, Red]],
>  PlotRange -> All,
>  PlotPoints -> 30,
>  Lighting -> "Neutral",
>  Mesh -> None]
>
>
> David Park
> djmpark at comcast.net
> http://home.comcast.net/~djmpark/index.html
>
>
>
> From: Michael B. Heaney [mailto:mheaney at alum.mit.edu]
>
>
> Here is simple example that demonstrates the problem:
>
> Plot3D[PDF[BinormalDistribution[0], {x, y}], {x, -40, 40}, {y, -40, 40},
>
>  PlotRange -> All, PlotPoints -> 200]
>
> Thanks,
>
> Michael
>
> On Thu, Mar 7, 2013 at 8:49 PM, Bob Hanlon <hanlonr357 at gmail.com> wrote:
>
> > I don't see a "dark halo" with the following
> >
> > Plot3D[
> >  PDF[BinormalDistribution[0], {x, y}],  {x, -3, 3}, {y, -3, 3}]
> >
> > Can you send a simple example that demonstrates the problem?
> >
> >
> > Bob Hanlon
> >
> >
> > On Thu, Mar 7, 2013 at 10:51 PM, Michael B. Heaney
> > <mheaney at alum.mit.edu>
> > wrote:
> > >
> > > Hi,
> > >
> > > When I plot a gaussian peak in Plot3D, there is a dark halo around
> > > the peak. Why is this? How can I get rid of it?
> > >
> > > Thanks,
> > >
> > > Michael
> > >
> > > --
> > > ----------------------------------------------------------
> > > Michael B. Heaney
> > > 3182 Stelling Drive
> > > Palo Alto, CA 94303 USA
> > > mheaney at alum.mit.edu
> > > www.linkedin.com/in/michaelbheaney
> > > ----------------------------------------------------------
> > >
> > >
> >
>
>
>
> --
> ----------------------------------------------------------
> Michael B. Heaney
> 3182 Stelling Drive
> Palo Alto, CA 94303 USA
> mheaney at alum.mit.edu
> www.linkedin.com/in/michaelbheaney
> ----------------------------------------------------------
>
>
>


-- 
----------------------------------------------------------
Michael B. Heaney
3182 Stelling Drive
Palo Alto, CA 94303 USA
mheaney at alum.mit.edu
www.linkedin.com/in/michaelbheaney
----------------------------------------------------------


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