Re: Problem with ContourPlot3D

*To*: mathgroup at smc.vnet.net*Subject*: [mg106992] Re: [mg106975] Problem with ContourPlot3D*From*: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>*Date*: Sun, 31 Jan 2010 05:55:38 -0500 (EST)*References*: <201001301211.HAA25117@smc.vnet.net>

Hi, you want the contour 0==y^2-Cos[x]/(4x+z). When is the left hand side zero and are there points that are not valid? expr = Together[y^2 - Cos[x]/(4 x + z)] {num, den} = {Numerator[#], Denominator[#]} &[expr] ContourPlot3D[num, {x, -5, 5}, {y, -5, 5}, {z, 0, 10}, Contours -> {0}, RegionFunction -> Function[{x, y, z}, Abs[den] > 0.001]] Cheers Patrick On Sat, 2010-01-30 at 07:11 -0500, Dominic wrote: > Hi. > > I'm unable to obtain a clean plot of this DE solution: > > ContourPlot3D[y^2 == Cos[x]/(4*x + z), > {x, -5, 5}, {y, -5, 5}, {z, 0, 10}] > > If I specify PlotPoints->50, Mathematica crashes. If I try > MaxRecursion->4, it also locks up. The command above does produce a > plot but it's jagged and has an "extraneous sheet" between the two > sections of the plot. Any way to get a nicer plot? > > Thanks, > > Dominic > >

**References**:**Problem with ContourPlot3D***From:*"Dominic" <miliotodc@rtconline.com>