As somebody else replied (but for some reason did not get through it) the solution to this is to convert the variable TIME3 from POSIXlt to POSIXct. It works like a charm.
Nevertheless, there is a bug in that R should give me a warning/error message, and not simply crash. I reported the bug to the relevant team. Thank you, Marco -- View this message in context: http://r.789695.n4.nabble.com/Possible-bug-in-data-table-tp4667025p4667096.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.