4 ms·

Does lubridate solve the unintended timezone conversions of POSIXct classes?

• hadley 12y ago
  Can you provide a bit more detail?
  • mapcar 12y ago
    In the R Help Desk 2004 (http://www.r-project.org/doc/Rnews/Rnews_2004-1.pdf http://www.r-project.org/doc/Rnews/Rnews_2004-1.pdf), Gabor Grothendieck recommends chron over POSIXct classes on account of the time zone conversions which occur when the tz attribute of the latter object is not "GMT". Will this not be a problem with lubridate? Thanks in advance.
    • hadley 12y ago
      I've never found that to be a problem in practice. Do you have an example where it's bitten you in practice? (Also you should use UTC and not GMT)
      • mapcar 12y ago
        Hi Hadley, yes for instance > as.chron("1970-01-01")+unclass(as.chron("2001-04-01")) [1] 04/01/01 > as.POSIXct("1970-01-01","EST")+unclass(as.POSIXct("2014-06-01","EST")) [1] "2014-06-01 05:00:00 EST" If there is any conversion necessary it is difficult to get back the original intended time.
        • hadley 12y ago
          What does adding two dates together mean?
          • mapcar 12y ago
            Isn't this the conventional way of converting variables which have been coerced to their numeric representations back to time/date classes?