[EMAIL PROTECTED] wrote: > Hi R-helpers, > > I have a dataframe (called data) with 100 columns, the columns of which are > named with integers ranging from 1900 to 1999. > > I wish to extract those columns which names are >=1950 and <=1970. > > I tried: > > data2<-subset(data,select=(names(data)>=1950 & names(data)<=1970)) > > but that doesn't work. > > Any ideas? > > The subset() function and in particular its select argument is playing tricks with the evaluation rules, mostly to be helpful, but sometimes apparently not...
Ordinary indexing should work: data[, names(data) >= "1950" & names(data) <= "1970"] (using quoted strings to emphasize that you are really comparing alphabetically. That is probably OK here, but beware that > "999" > 1999 [1] TRUE Also, BTW, check that names really are "1950", not "X1950" or so. Data frame methods like to rationalize column names to be valid variable names.) > Thanks! Mark > > [[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. > -- O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ 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.
