predictors(x, ...)NA.
randomForest, cforest,
ctree, rpart,
ipredbagg, bagging,
earth, fda,
pamr.train, superpc.train,
bagEarth and bagFDA, an attempt was made to
report the predictors that were actually used in the final model.The predictors function can be called on the model object (as opposed
to the train) object) and the package will try to find the
appropriate coed (if it exists).
In cases where the predictors cannot be determined, NA is returned.
For example, nnet may return missing values from
predictors.