Dataframe1 contains a list of specific dates. Dataframe2 contains a large dataset, one element of which is Date. How do I create a subset of Dataframe2 that excludes the dates from Dataframe1? I know how to do it with a left outer join vs null in SQL, but I can't figure out how to do it more directly via the subcripts that already exist? Dateframe1 Date 1/1/2010 1/18/2010 Dataframe2 Date Attribute Count 1/1/2010 Red 5 1/15/2010 Green 2 1/18/2010 Purple 8 1/19/2010 Yellow 3 ResultingDataframe (Dataframe2 minus the rows that have Dates in Dataframe1) Date Attribute Count 1/15/2010 Green 2 1/19/2010 Yellow 3 -- View this message in context: http://n4.nabble.com/Subscripting-tp1476330p1476330.html Sent from the R help mailing list archive at Nabble.com.
Something like:> df3 <- df2[ !(df2$date %in% df1$date), ]Might be what you want. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.snow at imail.org 801.408.8111> -----Original Message----- > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r- > project.org] On Behalf Of GL > Sent: Wednesday, February 10, 2010 12:26 PM > To: r-help at r-project.org > Subject: [R] Subscripting > > > Dataframe1 contains a list of specific dates. Dataframe2 contains a > large > dataset, one element of which is Date. How do I create a subset of > Dataframe2 that excludes the dates from Dataframe1? I know how to do it > with > a left outer join vs null in SQL, but I can't figure out how to do it > more > directly via the subcripts that already exist? > > Dateframe1 > > Date > 1/1/2010 > 1/18/2010 > > > Dataframe2 > > Date Attribute Count > 1/1/2010 Red 5 > 1/15/2010 Green 2 > 1/18/2010 Purple 8 > 1/19/2010 Yellow 3 > > ResultingDataframe (Dataframe2 minus the rows that have Dates in > Dataframe1) > > Date Attribute Count > 1/15/2010 Green 2 > 1/19/2010 Yellow 3 > > -- > View this message in context: http://n4.nabble.com/Subscripting- > tp1476330p1476330.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at 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.
On Feb 10, 2010, at 2:26 PM, GL wrote:> > Dataframe1 contains a list of specific dates. Dataframe2 contains a > large > dataset, one element of which is Date. How do I create a subset of > Dataframe2 that excludes the dates from Dataframe1? I know how to do > it with > a left outer join vs null in SQL, but I can't figure out how to do > it more > directly via the subcripts that already exist? > > Dateframe1 > > Date > 1/1/2010 > 1/18/2010 > > > Dataframe2 > > Date Attribute Count > 1/1/2010 Red 5 > 1/15/2010 Green 2 > 1/18/2010 Purple 8 > 1/19/2010 Yellow 3 >Something along the lines of this untested code: Dataframe2[ !(Dataframe2$Date %in% Dataframe1$Date) , ] ?"[" ?"%in%"> ResultingDataframe (Dataframe2 minus the rows that have Dates in > Dataframe1) > > Date Attribute Count > 1/15/2010 Green 2 > 1/19/2010 Yellow 3 > > -- > View this message in context: http://n4.nabble.com/Subscripting-tp1476330p1476330.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at 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.David Winsemius, MD Heritage Laboratories West Hartford, CT