Hi All, I'm fiddling with an program to read a text file containing periods that SAS uses for missing values. I know that if I had the original SAS data set instead of a text file, R would handle this conversion for me.
Data frames do not allow missing values in their indices but vectors do. Why is that? A search of the error message points out the problem and solution but not why they differ. A simplified program that demonstrates the issue is below. Thanks, Bob # Here's a data frame that has both periods and NAs. # I want sex to remain character for now. sex=c("m","f",".",NA) x=c(1,2,3,NA) myDF <- data.frame(sex,x,stringsAsFactors=F) rm(sex,x) myDF # Substituting NA into data frame does not work # due to NAs in the indices. The error message is: # missing values are not allowed in subscripted assignments of data frames myDF[ myDF$sex==".", "sex" ] <- NA myDF # This works because myDF$sex is a vector and vectors allow NAs in indexes. # Why don't data frames allow this? myDF$sex[ myDF$sex=="." ] <- NA myDF ========================================================= Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting Center U of TN Office of Information Technology 200 Stokely Management Center, Knoxville, TN 37996-0520 Voice: (865) 974-5230 FAX: (865) 974-4810 Email: [EMAIL PROTECTED] Web: http://oit.utk.edu/scc, News: http://listserv.utk.edu/archives/statnews.html ______________________________________________ R-help@stat.math.ethz.ch 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.