I would say that the use of Reduce in this context is bad practice. from ?Reduce :
"Reduce uses a binary function to successively combine the elements of a given vector and a possibly given initial value." combine() is obviously not a binary function. do.call() seems to be THE appropriate idiom. -- Bert On Fri, Jul 26, 2013 at 9:26 PM, arun <smartpink...@yahoo.com> wrote: > HI, > Using the example in ?combine > library(randomForest) > rf1 <- randomForest(Species ~ ., iris, ntree=50, norm.votes=FALSE) > rf2 <- randomForest(Species ~ ., iris, ntree=50, norm.votes=FALSE) > rf3 <- randomForest(Species ~ ., iris, ntree=50, norm.votes=FALSE) > rf.all <- combine(rf1, rf2, rf3) > lst1<- list(rf1,rf2,rf3) > > rf.allL<- do.call(`combine`,lst1) > #or > rf.allL<- Reduce(`combine,lst1) > identical(rf.all,rf.allL) > #[1] TRUE > A.K. > > > Is there a quick and easy way to pass randomForest objects contained in a > list into the combine() function? > > As a result of calling randomForest through lapply(), I now have 10 > randomForests in a list (rfors) > > I want to combine all 10 of them. Understandably combine(rfors) > doesn't work as it doesn't recognise the individual forests within the > list. I have spend quite sometime messing around with unlist(), lapply() > and apply() to try and extract the information in a suitable format but > to no avail. The only thing that works is combine(rfors[[1]], > rfors[[2]] ...etc). > > This is a bit cumbersome though, not least because the number of > random forests I'll need to combine is likely to change. Any sleek and > elegant solution to this someone can suggest? > > Thanks in advance for any help. > > Anna > > ______________________________________________ > 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. -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.