Hi Jim, Thanks for your response, although I was probably not clear about exactly what I want to achieve, please let me see if I can explain a little better...
There are certain (unknown) columns in my data that contain either NULL in every row, or the same value in every row (eg '1'). These columns are useless for modelling as there is no variation in the data. I need a way to automatically find and delete all these columns (it is not rows I want to delete, but the whole column, as in train$Variablexxx = NULL where Variablexxx needs to be automatically found. Thanks in advance, pdb -- View this message in context: http://r.789695.n4.nabble.com/eliminating-constant-variables-tp2284831p2284853.html Sent from the R help mailing list archive at Nabble.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.
