I know how to get the output I need, but I would benefit from an explanation why R behaves the way it does.
# I have a data frame x: x = data.frame(a=1:10,b=2:11,c=c(1,NA,3,NA,5,NA,7,NA,NA,10)) x # I want to toss rows in x that contain values >=6. But I don't want to toss my NAs there. subset(x,c<6) # Works correctly, but removes NAs in c, understand why x[which(x$c<6),] # Works correctly, but removes NAs in c, understand why x[-which(x$c>=6),] # output I need # Here is my question: why does the following line replace the values of all rows that contain an NA # in x$c with NAs? x[x$c<6,] # Leaves rows with c=NA, but makes the whole row an NA. Why??? x[(x$c<6) | is.na(x$c),] # output I need - I have to be super-explicit Thank you very much! -- Dimitri Liakhovitski ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
