Dear R-users, I am trying to get the plyr syntax right, without much success.
Given: d<- data.frame(cbind(x=1,y=seq(20100801,20100830,1))) names(d)<-c("first", "daterep") d2<-d # I can convert the daterep column in place the classic way: d$daterep<-as.Date(strptime(d$daterep, format="%Y%m%d")) # How to do it the plyr way? ddply(d2, c("daterep"), function(df){as.Date(df, format="%Y%m%d")}) # returns: Error in as.Date.default(df, format = "%Y%m%d") : # do not know how to convert 'df' to class "Date" Thanks for any hints, ---jean -- View this message in context: http://r.789695.n4.nabble.com/ddply-how-to-transform-df-column-in-place-tp3764037p3764037.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.