I've just started using R a couple of weeks ago and I'm new to programming.

I'm doing some EM algorithm clustering using the Mclust package provided in R. This seems to be exactly what I need, however the number of clusters that I get when I run it is more than I expect. I assume that my problem can be solved using prior control, but whenever I use the script

mclustBIC(mydata, prior = priorControl())

I get the following error message:

Error in chol.default(priorParams$scale) : 
  the leading minor of order 3 is not positive definite

Here's an example showing how prior control works:

treesBIC <- mclustBIC(trees) # default (no prior)
plot(treesBIC, legendArgs = list(x = "bottom", ncol = 2, cex = .75))

treesBICprior <- mclustBIC(trees, prior = priorControl()) # with prior
plot(treesBICprior, legendArgs = list(x = "bottom", ncol = 2, cex = .75))

Hi 

Try specifying G. The default is 9.

Sorry mean to give example code

With 5 cluster, G=1:5

testdata<-iris[,-5]

tt<- mclustBIC(testdata, G = 1:5)

plot(tt)

Default is 9 clusters.. G=1:9

 plot(mclustBIC(testdata))