Look at the merge command ?merge
Steve Friedman Ph. D. Ecologist / Spatial Statistical Analyst Everglades and Dry Tortugas National Park 950 N Krome Ave (3rd Floor) Homestead, Florida 33034 steve_fried...@nps.gov Office (305) 224 - 4282 Fax (305) 224 - 4147 "Roccato Alfredo (UniCredit)" <Alfredo.Roccato@ To unicredit.eu> "r-help@r-project.org" Sent by: <r-help@r-project.org> r-help-bounces@r- cc project.org Subject [R] join tables in R 05/04/2011 10:32 AM I'd to match-merge 2 tables in such a manner that I keep all the rows in table 1, but not the rows that are in both table 1 and 2. Thank you for your help, Alfredo > master <- data.frame(ID=2001:2011) > train <- data.frame(ID=2004:2006) > valid <- ??? in this example table valid should have the following > str(valid) Year: int 2001 2002 2003 2007 2008 2009 2010 2011 in SAS I'd do the following: data master; do id=2001 to 2011; output; end; run; data train; do id=2004 to 2006; output; end; run; data valid; merge master(in=a) train(in=b); by id; if a and not b; run; and in SQL: create table valid as select a.* from master where ID not in (select ID from train) [[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. ______________________________________________ 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.