[R] kde on Torus

[Tim Gruene]

Hello,

I have 2D-data on a torus, i.e. they are scattered within [0:2pi) and are
supposed to be periodic with period 2pi.

Is there a way in R for a kernel density estimation for such data? I found this
article http://www.dmqte.unich.it/personal/dimarzio/density46.pdf 
but 
a) I don't fully understand the article (my knowledge in statistics is poor)
b) I did not understand which Eq. represents the kernel(s)
c) I do not now R well enough to understand whether I can use kde2d or nprudens
   with an arbitrary kernel

My simple-minded attempt was to extend the data to [-2pi:4pi) and then use
kde2d, but I am wondering
a) how accurate is this
b) is there a way to do it properly on a torus.

Thanks a lot, Tim

-- 
--
Tim Gruene
Institut fuer anorganische Chemie
Tammannstr. 4
D-37077 Goettingen

GPG Key ID = A46BEE1A

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