Re: Help: Implicit 3D function
- To: mathgroup at smc.vnet.net
- Subject: [mg8012] Re: [mg7950] Help: Implicit 3D function
- From: "Keith S. Mersman" <c621746 at everest.cclabs.missouri.edu>
- Date: Wed, 30 Jul 1997 23:58:09 -0400
- Sender: owner-wri-mathgroup at wolfram.com
Claus, One way I can think of doing this is to solve for z = + or - Sqrt[30(1-x^2/10-y^2/20)] and then use Plot3D or ParametricPlot3D with these two functions of x and y. However, there is an easier way. Using modified spheical coordinates we see that if x= Sqrt[10] Sin[s] Cos[t] y= Sqrt[20] Sin[s] Sin[t] z= Sqrt[30] Cos[s] where s varies from 0 to Pi and t varies from 0 to 2 Pi, then this is a parametrization of the ellipsoid x^2/10+y^2/20+z^2/30=1 Then you can use ParametricPlot3D for this parametrization. On Fri, 25 Jul 1997, Claus Wisser wrote: > Hello, > > I'm new to Mathematica and hopefully there is someone out there who can > help me. > I would like to plot a a implict 3D-function, e.g. x^2/10+y^2/20+z^2/30=1. > Please, can someone help me and tell me how to do it. > > Thank you, > Claus > > Claus.Wisser at studbox.uni-stuttgart.de > >