Dear David Thank you for your e-mail I believe that equivalent to Stata egen tag is simply
df$tag <- df[!duplicated(df[c("station","week")]),] I am not sure about egen count It might be something like aggregate(station~week, df, function(x)sum(!is.na(x)), na.action = na.pass) I made this question while making very first steps in R after actively using Stata for 3 years. And I underestimated the extent of flexibility of R. But after your answer on one of my previous questions I realized that I can use, for instance mean(tapply(<sth>)) or table(<sth>)/<sth> right away which is great With best regards Denis ----- Original Message ---- From: David Winsemius <dwinsem...@comcast.net> To: Denis Kazakevich <den2...@yahoo.com> Sent: Sun, 23 January, 2011 17:56:53 Subject: Re: [R] Equivalent to Stata egen tag On Jan 16, 2011, at 6:48 PM, Denis Kazakevich wrote: > What are the R equivalents to the Stata command egen tag > and > egen count? > > egen station_week_tag = tag(station week) I have looked at similar questions in the past and gone to the Stata online docs and tried to make some sense of them and even posted an attempt at an answer. The documents appeared to be to be fairly cryptic. Much more so that the R documentation. I was somewhat snottily informed by experienced Stata users that I had completely misunderstood the documentation and that egen was much more rich an varied that I understood. So I've given answering Stata questions. Given the protean nature of the egen I think it's unrealistic of you to expect that just posting code will communicate what you intended. -- David Winsemius, MD Heritage Laboratories West Hartford, CT ______________________________________________ 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.