Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2009

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Creating a sign chart

  • To: mathgroup at smc.vnet.net
  • Subject: [mg98936] Re: Creating a sign chart
  • From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
  • Date: Wed, 22 Apr 2009 05:11:37 -0400 (EDT)
  • Organization: Uni Leipzig
  • References: <gsivd0$9aa$1@smc.vnet.net>
  • Reply-to: kuska at informatik.uni-leipzig.de

Hi,

f[x_, y_] := x*y*Exp[-x^2 - y^2]

Plot3D[Evaluate[
   Sign[Det[{{D[f[x, y], {x, 2}], D[f[x, y], x, y]},
            {D[f[x, y], x, y], D[f[x, y], {y, 2}]}}]]], {x, -2,
   2}, {y, -2, 2}]

??

or what ever a sign chart is ..

Regards
   Jens

davef wrote:
> Is it possible to render a sign chart in Mathematica 10?
> 
> Typically a sign chart is used with the first and second derivatives to identify extrema.  I know there are other ways to convey this information.  However, in my case I  need to demonstrate a sign chart by means of an illustation.  I can create a graphic in Visio and import into Mathematica but I would prefer if there were a means of generating such a chart directly in Mathematica.
> 
> Something like:
> 
> +++++++++++++++------------
> 
> 
> Thanks for any ideas.
> Dave
> x2373
> 


  • Prev by Date: Re: Re: Mathematica documentation - for newest
  • Next by Date: Re: Advanced plotting
  • Previous by thread: Re: Creating a sign chart
  • Next by thread: multiple plots