Re: Getting started with 3D cardioid

*To*: mathgroup at smc.vnet.net*Subject*: [mg112073] Re: Getting started with 3D cardioid*From*: David Thomson <aetherwizard at gmail.com>*Date*: Sun, 29 Aug 2010 02:49:24 -0400 (EDT)*References*: <i57rp6$1in$1@smc.vnet.net>

On Aug 27, 3:08 am, Alexei Boulbitch <alexei.boulbi... at iee.lu> wrote: > Hi, David, > > To answer your first question: > I do not understand, where the figure 68 for the average radius comes > from? The number is not 68, but decimal point 68. ie ".68". > Concerning your second question: > > I am not aware of the horn shape and it would be helpful, if you post > the corresponding formula in whatever coordinates. My ignorance is to blame for providing incomplete information. The shape I am trying to model is here" http://www.secrets-of-the-aether.com/images/stories/idealtcshape-damped_wave.jpg This shape comes from: r[t_] = Sin[t + 1]/t PolarPlot[r[t], {t, 0, \[Pi]}] By trial and error, I got the graph about where it should be: r[t_] = Sin[t + 1]/t^2; x[t_] = r[t] Cos[t]; y[t_] = r[t] Sin[t]; RevolutionPlot3D[{x[t + 1], y[t - \[Pi]]}, {t, 0, 1}, RevolutionAxis -> x] I tried the Show function to merge the above graph with the cardioid graph, but got error messages. How do I merge the SphericalPlot3D image with the RevolutionPlot3D image? Thanks, Dave