I got this erro Error in c("red", "blue", "green")[r] : invalid subscript type 'S4' -- View this message in context: http://r.789695.n4.nabble.com/How-to-represent-certain-values-in-a-file-as-we-want-tp4662925p4662935.html Sent from the R help mailing list archive at Nabble.com.