Re: Re: 3D plotting problem

• To: mathgroup at smc.vnet.net
• Subject: [mg51771] Re: [mg51743] Re: 3D plotting problem
• From: Henning Heiberg-Andersen <Henning.Heiberg-Andersen at fi.uib.no>
• Date: Mon, 1 Nov 2004 02:53:19 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

```I am sorry that I was not clear enough about the nature of my problem,
which I will try to illustrate by the following example:

If 'Cos' is replaced by 'Cosh' in the command

ContourPlot3D[Cos[Sqrt[x^2+y^2+z^2]],{x,-2,2},{y,0,2},{z,-2,2}]

an empty plot box appears.

It seems to me that it is problematic to make 3D contour plots
involving exponential functions, and I hope somebody can suggest
a remedy for this.

Best regards,
Henning Heiberg-Andersen

On Sun, 31 Oct 2004, Bill Rowe wrote:

> On 10/30/04 at 3:47 AM, Henning.Heiberg-Andersen at fi.uib.no (Henning
> Heiberg-Andersen) wrote:
>
> >I find myself unable to make a 3D plot of the atomic 2p orbital
>
> >f_z(2p,x,y,z;a)=z*Exp[-a*Sqrt[x^2+y^2+z^2]].
>
> >As far as I can understand, 'ContourPlot3D' is the only option, but
> >it gives either an empty plot box or a flat sheet.
>
> >Can anyone suggest a way out?
>
> You did not make it clear exactly what you tried to plot. If it was the expression you posted, then try re-writting your function as
>
> f[x_, y_, z_, a_] := z*Exp[-a*Sqrt[x^2 + y^2 + z^2]]
>
> Here, I've eliminated the _z from the function name as Mathematica doesn't allow underscore characters in function names f_z is interpeted by Mathematica to be any expression with Head z given a name f, not what you want.
>
> Changed the "(" to "[" to corespond to proper Mathematica syntax
>
> dropped 2p from the arguements since it does not appear on the rhs
>
> added a underscore to all of the other arguments. Using x_ is interpreted by Mathematica as being any valid expression and is given a local name of x
>
> Replaced Set ("=") with DelayedSet (":=")
> --
> To reply via email subtract one hundred and four
>
>

```

• Prev by Date: Re: MPS format, Linear Programming, and Optimization'MPSData
• Next by Date: Re: newbie question on functions
• Previous by thread: Re: 3D plotting problem
• Next by thread: Re: Re: Re: 3D plotting problem