Hi, Here is a follow up, I resolve the problem in another way. " > e <- evaluate_Weka_classifier(p) > print(subset) > print(e$details[1]) > return(e$details[1])"
change this lines to " e <- sum(iris$Species == predict(p))/nrow(iris) print(subset) print(e) return(e) ================ It works well, but I still don't understand why the previous one didn't work. Maybe there is a compatibility problem... Yanwei On Sep 7, 2011, at 8:47 PM, Yanwei Song wrote: > Hi all, > > Last post didn't give the plain format: > > I was trying to combine RWeka and FSelector, and do the forward feature > selection with J48/C5.4 decision tree: > > Here is the code: > #================== > library(RWeka) > library(FSelector) > library(rpart) > > > data(iris) > evaluator <- function(subset) { > p <- J48(as.simple.formula(subset, "Species"), data=iris) > e <- evaluate_Weka_classifier(p) > print(subset) > print(e$details[1]) > return(e$details[1]) > } > > > subset <- forward.search(names(iris)[-5], evaluator) > ========================= > I got this error, when I ran it: > > Error in paste(attributes, sep = "", collapse = " + ") : > cannot coerce type 'closure' to vector of type 'character' > > I don't know how I could fix this problem. > Thanks. > > > Yanwei > > > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.