Using the sqldf package you could do an SQL join with the indicated condition in your where clause. See the examples section of this page: http://sqldf.googlecode.com
On Sat, Mar 20, 2010 at 10:20 AM, James Rome <jamesr...@gmail.com> wrote: > I have two data frames of flight data, but they have very different > numbers of rows. They come from different sources, so the data are not > identical. > >> names(oooi) > [1] "FltOrigDt" "MkdCrrCd" > [3] "MkdFltNbr" "DprtTrpnStnCd" > [5] "ArrTrpnStnCd" "ActualOutLocalTimestamp" > [7] "ActualOffLocal" "ActualOnLocal" > [9] "ActualInLocal" "ArrivalGate" > [11] "DepartureGate" "Flight" > [13] "OnDate" "MinutesIntoDay" > [15] "OnHour" "pt" > >> names(runway) > [1] "OnDateTime" "IATA" "ICAO" "Flight" > [5] "AircraftType" "Tail" "Arrived" "STA" > [9] "Runway" "From.To" "Delay" "OnDate" > [13] "MinutesIntoDay" "pt" > > These sets have several hundred thousand rows. > > In both sets, pt is a POSIXct for the arrival time (from different > sources). They are not identical, but surely should be within an hour of > each other (hopefully a lot less), and the Flight fields must be the > same. So > (abs(runway$pt - oooi$pt) < 3600) & (runway$Flight == oooi$Flight) > should pick out the corresponding rows in the two data sets (if there is > a match). > > What I need to do is to take the Runway from runway and insert it into > the oooi df for the correct flight. > > What is the best way to do this in R? > > Thanks, > Jim Rome > > ______________________________________________ > 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.
