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Topic: dark halo around gaussian peak in Plot3D?
Replies: 9   Last Post: Mar 10, 2013 12:47 AM

 Messages: [ Previous | Next ]
 David Reiss Posts: 603 Registered: 2/24/06
Re: dark halo around gaussian peak in Plot3D?
Posted: Mar 9, 2013 5:26 AM

It probably has to do with numerical inaccuracies. The problem is
removed by "Chop"ing the numerical output:

Plot3D[Chop@Evaluate@PDF[BinormalDistribution[0], {x, y}], {x, -40,
40}, {y, -40, 40}, PlotRange -> All, PlotPoints -> 50]

--David

On Mar 8, 4:46 pm, "Michael B. Heaney" <mhea...@alum.mit.edu> wrote:
> 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 <hanlonr...@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 <mhea...@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
> > > mhea...@alum.mit.edu
> > > ----------------------------------------------------------

>
> --
> ----------------------------------------------------------
> Michael B. Heaney
> 3182 Stelling Drive
> Palo Alto, CA 94303 USA
> ----------------------------------------------------------

Date Subject Author
3/8/13 Bob Hanlon
3/8/13 Michael B. Heaney
3/9/13 David Reiss
3/9/13 Bob Hanlon
3/9/13 Bob Hanlon
3/9/13 Michael B. Heaney
3/9/13 David Park
3/10/13 Michael B. Heaney