Re: how to visualize 3+D normal density contour?

• To: mathgroup at smc.vnet.net
• Subject: [mg64192] Re: how to visualize 3+D normal density contour?
• From: "Steve Luttrell" <steve_usenet at _removemefirst_luttrell.org.uk>
• Date: Sat, 4 Feb 2006 04:13:52 -0500 (EST)
• References: <dru754\$a18\$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Here are 3 examples of what you want:

<<Graphics`ContourPlot3D`

Spherical case:

ContourPlot3D[Exp[-{x, y, z} . {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}} .
{x, y, z}] - 0.5, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}];

Axis-aligned ellipsoidal case:

ContourPlot3D[Exp[-{x, y, z} . {{1, 0, 0}, {0, 2, 0}, {0, 0, 4}} .
{x, y, z}] - 0.5, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}];

More general ellipsoidal case:

ContourPlot3D[Exp[-{x, y, z} . {{2, 2, 1}, {0.5, 2, 1}, {1, 2, 4}} .
{x, y, z}] - 0.5, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}, PlotPoints ->
5];

Steve Luttrell

"gino" <loseminds at hotmail.com> wrote in message
news:dru754\$a18\$1 at smc.vnet.net...
> Hi all,
>
> How do I visualize a contour of a tri-variate normal distribution?
>
> I just like to see the ellipsoid very much. I hope there is a easy way or
> existing method.
>
> Thank you a lot!
>
>
>

```

• Prev by Date: Re: String Input and Variable Setting
• Next by Date: Notebooks, packages, cells, and literate programming
• Previous by thread: Re: how to visualize 3+D normal density contour?
• Next by thread: NIntegrate[Abs] bug in v5.1, not v5.0