Re: Methods for plotting
- To: mathgroup at smc.vnet.net
- Subject: [mg86309] Re: Methods for plotting
- From: "Steve Luttrell" <steve at _removemefirst_luttrell.org.uk>
- Date: Sat, 8 Mar 2008 05:40:40 -0500 (EST)
- References: <fqqs4b$kgg$1@smc.vnet.net>
Your expression is not written in Mathematica. I assume the left hand side of your equation is meant to be lhs=Exp[-x]/((x^2 + 1) (y^2 + 2) (z^2 + 1)) + Exp[-2 y]/((x^2 + 2) (y^2 + 2) (z^2 + 1)) + Exp[-3 z]/((x^2 + 1) (y^2 + 2) (z^2 + 3)) Assuming x,y,z are all real-valued, then each of the 3 terms in this expression is positive, so lhs can never be zero, so there is no contour surface lhs==0 for you to plot. An exception is when x,y,z all tend to +Infinity which makes lhs-->0. Stephen Luttrell West Malvern, UK "Paolo" <paolomarracino at hotmail.com> wrote in message news:fqqs4b$kgg$1 at smc.vnet.net... > Hi, I'm new in this forum and I hope you'll help me to solve a little > problem with Mathematica(5.0), that I just started to use. I have an > equation (coming from the divergence of a vector) and it's form is similar > to: > [exp(-x)]/[(x^2+1)(y^2+2)(z^2+1)]+ > [exp(-2y)]/[(x^2+2)(y^2+2)(z^2+1)]+ > [exp(-3z)/[(x^2+1)(y^2+2)(z^2+3)]=0 > > I have difficulties to plot this implicit function, i used Plot3d and > ImplicitPlot with no success and the error message that I get involves the > non-algebraic way the programm uses to solve the equation. > Is there any other Plot-type function that can possibly solve this > problem? >