Dear all,
I have trained a J48 classifier in RWeka but when I try to predict on new
data I get the following exceptions:

fit <- J48(...)
yNew <- predict(fit, x, type="probability");

Error in .jcall("RWekaInterfaces", "[D", "distributionForInstances",
.jcast(classifier,  :
  java.lang.NullPointerException

What could be the cause of this ?
I am using R version 2.10.0 on a Linux server.

Thanks,
Markus

	[[alternative HTML version deleted]]

