If df is your dataframe, try aggregate(df$Year,list(df$Id),min)
--- On Fri, 30/5/08, Jojje Andersson <[EMAIL PROTECTED]> wrote: > From: Jojje Andersson <[EMAIL PROTECTED]> > Subject: [R] Aggregate by First case > To: "[email protected]" <[email protected]> > Received: Friday, 30 May, 2008, 5:13 PM > Hello! > > I have an maybe a to a simple question but I cant get it > right. > > I have a dataframe with in one column an id-variable and in > another a year-variable. One id-number can occur several > years. > I have sorted the dataframe on id then on year so the same > id-number is sorted by year with the first occurens at top. > > Now I want to make a subset of this dataframe with just the > first year the id-number occur, so the first case of every > id. > > Id Year > 123456 2001 > 123456 2002 > 123456 2003 > 655432 2001 > 655432 2002 > 655432 2003 > > Is there a simple command I can do? > > Thanks! > > Jojje > > > _________________________________________________________________ > [[elided Hotmail spam]] > > [[alternative HTML version deleted]] > > ______________________________________________ > [email protected] 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. ______________________________________________ [email protected] 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.
