Hi all, I was just radomly playing with R and got the following error when trying to filter a data frame using a string:
> Angel <- c(7,8,6,9,10) > Buffy <- c(8,9,4,9,10) > Firefly <- c(9,9,10,10,10) > DrHorrible <- c(10,9,9,10,10) > my.df <- data.frame(Angel, Buffy, Firefly, DrHorrible) > my.df["DrHorrible"] DrHorrible 1 10 2 9 3 9 4 10 5 10 > my.df[-"DrHorrible"] Error in -"DrHorrible" : invalid argument to unary operator > I know how to work around this problem quite easily, I'm just curious as to why the my.df[-"DrHorrible] statement didn't work? Cheers, Tony OS = win XP > sessionInfo() R version 2.8.1 (2008-12-22) i386-pc-mingw32 locale: LC_COLLATE=English_United Kingdom.1252;LC_CTYPE=English_United Kingdom. 1252;LC_MONETARY=English_United Kingdom. 1252;LC_NUMERIC=C;LC_TIME=English_United Kingdom.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base > ______________________________________________ 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.