[R] error in kmeans

[Uwe Ligges]

Asha Jayanthi wrote:

> I am trying to generate kmean of 10 clusters for a 165 x 165 matrix.
> 
> i do not see any errors known to me. But I get this error on running the 
> script
> 
> Error: empty cluster: try a better set of initial centers
> 
> the commands are
> 
> M <-matrix(scan("R_mutual",n = 165 * 165),165,165,byrow = T)
> 
> cl <- kmeans(M,centers=10,20)
> len = dim(M)[1]
> ....
> ....
> 
> I ran the same script last night and it was working prefectly. I have 
> not made any changes at all !!!And this is very strange. This evening 
> when I ran the same script i am getting this error. My matrix file is 
> also untouched.
> 
> Can any one let me know how to go about this. I must generate 10-mean 
> clusters
> Is there anyother way of doing it ? and how to avoid such error in future?


Please read the docs! The help page tells you:

"centers: Either the number of clusters or a set of initial cluster 
centers. If the first, a random set of rows in x are chosen as the 
initial centers."

So, the rows are *randomly* choosen. If this does not work, why don't 
you specify a fixed set of, e.g., 10 rows?

Uwe Ligges




> Asha
> 
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