[R] is.na() == TRUE for POSIXlt time / date of "2014-03-09 02:00:00"

[Duncan Murdoch]

On 30/07/2014 1:08 PM, John McKown wrote:
> "I'm so confused!" Why does is.na() report TRUE for a POSIXlt date &
> time of 2014-03-09 02:00:00 ?
>
> > q
> [1] "2014-03-09 02:00:00"
> > is.na(q)
> [1] TRUE
> > as.POSIXct(q)
> [1] NA
> > dput(q)
> structure(list(sec = 0, min = 0L, hour = 2, mday = 9L, mon = 2L,
>      year = 114L, wday = 0L, yday = 67L, isdst = 0L, zone = "",
>      gmtoff = NA_integer_), .Names = c("sec", "min", "hour", "mday",
> "mon", "year", "wday", "yday", "isdst", "zone", "gmtoff"), class = c("POSIXlt",
> "POSIXt"))

I see an NA in there for the GMT offset, and no timezone.

Duncan Murdoch
> > str(q)
>   POSIXlt[1:1], format: "2014-03-09 02:00:00"
> >
>
>