On 01-Apr-09 15:49:40, Jose Iparraguirre D'Elia wrote: > Dear all, > Say I have the following dataset: > >> DF > x y z > [1] 1 1 1 > [2] 2 2 2 > [3] 3 3 NA > [4] 4 NA 4 > [5] NA 5 5 > > And I want to omit all the rows which have NA, but only in columns X > and Y, so that I get: > > x y z > 1 1 1 > 2 2 2 > 3 3 NA
Roll up your sleeves, and spell out in detail the condition you need: DF<-data.frame(x=c(1,2,3,4,NA),y=c(1,2,3,NA,5),z=c(1,2,NA,4,5)) DF # x y z # 1 1 1 1 # 2 2 2 2 # 3 3 3 NA # 4 4 NA 4 # 5 NA 5 5 DF[!(is.na(rowSums(DF[,(1:2)]))),] # x y z # 1 1 1 1 # 2 2 2 2 # 3 3 3 NA Hoping this helps, Ted. > If I use na.omit(DF), I would delete the row for which z=NA, obtaining > thus > > x y z > 1 1 1 > 2 2 2 > > But this is not what I want, of course. > If I use na.omit(DF[,1:2]), then I obtain > > x y > 1 1 > 2 2 > 3 3 > > which is OK for x and y columns, but I wouldn't get the corresponding > values for z (ie 1 2 NA) > > Any suggestions about how to obtain the desired results efficiently > (the actual dataset has millions of records and almost 50 columns, and > I would apply the procedure on 12 of these columns)? > > Sincerely, > > Jose Luis > > Jose Luis Iparraguirre > Senior Research Economist > Economic Research Institute of Northern Ireland > > > > [[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. -------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 01-Apr-09 Time: 18:00:53 ------------------------------ XFMail ------------------------------ ______________________________________________ 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.
