The base help file replace.Rd has no usage example. Might this example be helpful? \examples{ foo <- c("Yes","n","no answer") foo <- replace(foo, list=c(2, 3), values=c("No?, NA)) foo # "Yes" "No" NA } Also, the Rd file doesn?t point to other relevant functions the user coming here might find useful. I?d suggest: \seealso{ \code{\link{rename} (reshape package)} } -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.