Thanks, David! On Thu, Feb 24, 2011 at 11:30 AM, David Winsemius <dwinsem...@comcast.net>wrote:
> > On Feb 24, 2011, at 1:23 PM, Changbin Du wrote: > > HI, Dear R community, >> >> I try to create 100 dummy variables like the following: >> >> ack$id_1 <- (ack$ID==1)*1 >> ack$id_2 <- (ack$ID==2)*1 >> .. >> . >> ack$id_100 <- (ack$ID==100)*1 >> >> >> I used the following codes: >> >> for(i in 1:100){ >> ack$id_[i] <- (ack$ID==i)*1 >> > > You are creating only one new column named ack$id_ > > Putting the "[" operator with a numeric argument after does not name a new > column. > > > } >> But only one column is created, can anyone help me? >> > > If I tell you how to do that I would only be hurting you. You should be > using factors. The modeling functions should all be capable of accepting > them and if you are writing your own then it seems only sensible that you > follow their example. > > >> > > -- > > David Winsemius, MD > West Hartford, CT > > -- Sincerely, Changbin -- Changbin Du DOE Joint Genome Institute Bldg 400 Rm 457 2800 Mitchell Dr Walnut Creet, CA 94598 Phone: 925-927-2856 [[alternative HTML version deleted]] ______________________________________________ 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.