[R] Scatterplot3d-proposal

[Atte Tenkanen]

> 
> 
> Duncan Murdoch wrote:
> > On 1/23/2007 6:38 AM, Atte Tenkanen wrote:
> >> Hi,
> >>
> >> Does somebody know if there is some trick to betoken the 
> starting points ("on the floor") of the vertical lines in 
> scatterplot3d-plots.
> >> I'd prefer something like that one in the example here
> >>
> >> http://users.utu.fi/attenka/proposal3d.jpg
> >>
> >> If this is not possible, could this option be added? Sometimes 
> it is not easy to distinguish objects behind the others and for 
> instance in this example picture the case nr. 21 is important.
> > 
> > scatterplot3d() returns a list of functions which could help with 
> this, 
> > in particular the points3d function.
> 
> Right, or rather use the returned function xyz.convert, as in:
> 
> s3d <- scatterplot3d(1:10, 1:10, 1:10, type="h")
> s3d$xyz.convert(5, 5, 0)
> 
> Now you got coordinates for the point on the plane with z=0 
> projected 
> from (5,5,5). It should be easy now to add circles, ellipses or 
> whatever 
> you like.
> 
> Uwe Ligges
> 

Thanks! This seems to work. 

http://users.utu.fi/attenka/ellipses_in3Db.png

I only had to change that (5,5,0) to (5,5,0.4). I'm not sure about the reason, is it because of the minimum of x- or y-coordinate in my plot or what?

Atte