Hi, see this example. I hope I helped you a little bit. Bye Vito
dati X Y Z 1 10 0 "0" 2 0 20 "60" 3 30 40 "50" 4 11 12 3" > dati[dati==0]<-NA > dati X Y Z 1 10 NA "0" 2 NA 20 "60" 3 30 40 "50" 4 11 12 3" ===== Diventare costruttori di soluzioni Became solutions' constructors "The business of the statistician is to catalyze the scientific learning process." George E. P. Box Visitate il portale http://www.modugno.it/ e in particolare la sezione su Palese http://www.modugno.it/archivio/cat_palese.shtml ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
