Posting some sample data would help, but I think something like this is what you want
data[data$school=='Cornell University',] For example CO2[CO2$Type=='Quebec',] Tom 2011/3/26 Sebastián Daza <sebastian.d...@gmail.com>: > Hi everyone, > I have just got different samples from a dataframe (independent and > exclusive, there aren't common elements among them). I want to create a > variable that indicate the sampling selection of the elements in the > original dataframe (for example, 0 = no selected, 1= sample 1, 2=sample 2, > etc.). > > I have tried to do it with ifelse command, but the problem is that the > second line replaces the values of the first line, and I haven't been able > to do it with the if command (I got this error: In if (data$school %in% > sample1) { : > the condition has length > 1 and only the first element will be used) > > data$selection <- ifelse(data$school %in% sample1, 1, 0) > data$selection <- ifelse(data$school %in% sample2, 2, 0) > > Any ideas? > Thank you in advance. > > -- > Sebastián Daza > sebastian.d...@gmail.com > > ______________________________________________ > 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.