subset should work fine. My guess would be that Electrode is a character or factor variable. Use str() to see what kind of variables you have in the data set.
If we call the data set dat1 this works. subset(dat1, dat1$Electrode =="FP1" | dat1$Electrode =="FP2" | dat1$Electrode == "F4") John Kane Kingston ON Canada > -----Original Message----- > From: mancinisim...@yahoo.it > Sent: Fri, 10 Aug 2012 10:07:31 +0100 (BST) > To: r-help@r-project.org > Subject: [R] subsetting levels of a vector > > Hi, > > > I need to subset different levels of vector in a dataset to create a new > dataframe that contains only these. These observations are not numerical, > so I can't use the subset() function (at least this is the response I get > from R). > Suppose the dataframe looks like this: > > > > ParticipID ERP Electrode > 1 s1 0.0370 FP1 > 2 s2 35.0654 FP2 > 3 s3 -3.3852 F4 > 4 s4 2.6119 P3 > 5 s5 0.1224 P4 > 6 s6 -5.3153 O1 > > > I want to create a subset of the dataframe with only the FP1, FP2, F4 > levels of Electrode, how do I do? > (actually the levels I have to filter are much more than these three, but > this is just to give an example). > > I know this is a trivial question, but I am still getting familiar with > R... > > Thanks a lot, > > s. > > [[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. ____________________________________________________________ FREE 3D MARINE AQUARIUM SCREENSAVER - Watch dolphins, sharks & orcas on your desktop! ______________________________________________ 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.
