Confocal Quadrics

Author

Eric W. Weisstein
June 10, 2004

This notebook downloaded from http://mathworld.wolfram.com/notebooks/Surfaces/ConfocalQuadrics.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/ConfocalQuadrics.html.

©2005 Wolfram Research, Inc. except for portions noted otherwise

Initialization

<<Hidekazu`Quadrics`
<<Hidekazu`Knife`

?quadrics

g[x_,y_,z_,k_]:=x^2/(9-k)+y^2/(4-k)+z^2/(1-k)-1

solg[a_,b_,c_]:=Chop[N[Solve[g[a,b,c,k]==0,k]]]

gs=g[x,y,z,k]/.solg[5,3,2];

p=Insert[Partition[gs,1],4,{2,2}]

q=quadrics[p,Boxed->False,Axes->False]

LiveGraphics3D

<<Utilities`LiveGraphics3D`

WriteLiveForm["confquad.m",q]

WriteLiveForm["confquad.m",DropInnerPolygons[NonIntersectingPolygons[quadrics[p,opts]]]]

Takes forever (i.e., > 6 hours)