Dear Charles, When you put TERM in a data frame, by default it was converted to a factor, which is already stored as integers. Thus, if I understand correctly what you want, the following will work:
> sc$TERM [1] 200208 200701 201201 Levels: 200208 200701 201201 > unclass(sc$TERM) [1] 1 2 3 attr(,"levels") [1] "200208" "200701" "201201" > class(unclass(sc$TERM)) [1] "integer" Note that the original class designations are presented in the "levels" attribute. This assumes that all of the class designations that you want to use appear in sc$TERM. You already received some suggestions for the way that you originally posed the problem (where there were classes in TermList not appearing in sc$TERM). I hope this helps, John ------------------------------------------------------- John Fox, Professor McMaster University Hamilton, Ontario, Canada http://socserv.mcmaster.ca/jfox/ > -----Original Message----- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Charles > Stangor > Sent: January-22-15 11:01 AM > To: r-help@r-project.org > Subject: [R] 'which' statement for recode? > > Hi, > > Is there a way to easily convert the list of course terms into sequential > integers in the dataframe (see code below)? > > eg. "199801" = 1; "199808"=2 > > I know I can use recode but shouldn't "which" work? > > Thanks in advance! > > > sc = data.frame(c("200208", "200701", "201201")) > names(sc) = c("TERM") > > TermList = c(NA, "199801", "199808", "199901", "199908", "200001", "200008", > "200101", "200108", > "200201", "200208", "200301", "200308", "200401", "200408", "200501", > "200508", > "200601", "200608", "200701", "200708", "200801", "200808", "200901", > "200908", > "201001", "201008", "201101", "201108", "201201", "201308", "201401", > "201408") > > which(TermList==sc$TERM) > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
