Can someone point me to the proper place in the documentation or on the Wiki where I can learn how to get R to stop interpreting the string "NA" as something special? I have a table in a database which contains (among other things) country codes and continent codes. The standard set of two-letter codes includes "NA" to denote "North America". I learned of the "na.strings" parameter for RODBC's "sqlQuery", being able to shut down this interpretation when data is read in.
However, in the program which uses this data, I (must) have some other instance where the "NA" gets spontaneously"interpreted as "not available", shows up in vectors and lists as "<NA>", and breaks function. I temporarily solved the problem by defining all instances of "NA" in the database as "NAC". It still would be good to know a generaly solution. I've seen something mentioned in conjunction with "options", but I'm not sure what that is about. Thanks much, - Jan, Akamai Technologies, Cambridge, MA ______________________________________________ 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.