[R] rgl: ellipse3d with axes

[Michael Friendly]

Duncan Murdoch wrote:
>
> The normals component contains the surface normals.  It is used to 
> help in rendering the surface, but isn't much use for your purposes.
> Unfortunately, I'm not familiar enough with the internals of princomp 
> to tell you how to get the axes you want.
>
> Duncan Murdoch

OK, then let me repharase it. The axes of the unit  sphere are like

axes <- matrix(
    c(0, 0, -1,   0, 0, 1,
       0, -1, 0,   0, 1,  0,
       -1, 0, 0,   1, 0, 0),  6, 3, byrow=TRUE)
taken in pairs.  I'd like to transform these coordinates the same was as 
in ellipse3d() and add them to the plot.

-- 
Michael Friendly     Email: friendly AT yorku DOT ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
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