I have found a strange "ifelse" behaviour (I think) This works:
> ifelse(T,1+1,1+2) [1] 2 > ifelse(F,1+1,1+2) [1] 3 Maybe I missed something about R internals, but why > ifelse(T,print("hello"),print("goodbye")) [1] "hello" [1] "hello" > ifelse(F,print("hello"),print("goodbye")) [1] "goodbye" [1] "goodbye" values are returned two times? I'm not sure: if it's a bug I'll post it immediately Thank You Luca Version: platform = i486-pc-linux-gnu arch = i486 os = linux-gnu system = i486, linux-gnu status = major = 2 minor = 4.1 year = 2006 month = 12 day = 18 svn rev = 40228 language = R version.string = R version 2.4.1 (2006-12-18) Locale: LC_CTYPE=it_IT.UTF-8;LC_NUMERIC=C;LC_TIME=it_IT.UTF-8;LC_COLLATE=it_IT.UTF-8;LC_MONETARY=it_IT.UTF-8;LC_MESSAGES=it_IT.UTF-8;LC_PAPER=it_IT.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=it_IT.UTF-8;LC_IDENTIFICATION=C Search Path: .GlobalEnv, package:MASS, package:utils, package:stats, package:graphics, package:grDevices, package:methods, Autoloads, package:base ______________________________________________ R-help@stat.math.ethz.ch 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.