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 > >

**Follow-Ups**:**Re: Re: Re: 3D plotting problem***From:*DrBob <drbob@bigfoot.com>