[R] kmeans error (bug?)

[Murad Nayal]

Hello,

I have been getting the following intermittent error from kmeans:

>str(cavint.p.r)
 num [1:1967, 1:13] 0.691 0.123 0.388 0.268 0.485 ...
 - attr(*, "dimnames")=List of 2
  ..$ : chr [1:1967] "6" "49" "87" "102" ...
  ..$ : chr [1:13] "HYD" "NEG" "POS" "OXY" ...
> set.seed(34)
> kmeans(cavint.p.r,centers=34)
Error: empty cluster: try a better set of initial centers

the seed being equal to the number of centers in this case is just a
coincidence. I've encountered the same error with or without setting the
seed at different numbers of clusters.

there is nothing particularly unusual about cavint.p.r (no NAs, NULLs),
except maybe for the fact that the rows sum to 1.

> sum(is.na(cavint.p.r))
[1] 0
> sum(is.nan(cavint.p.r))
[1] 0
> 

I thought kmeans should select initial centers from the data if not
given explicitly! any idea what might be going wrong?

I am running R 1.7.0

many thanks

Murad