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

[John McKown]

On Wed, Jul 30, 2014 at 12:18 PM, Duncan Murdoch
<murdoch.duncan at gmail.com> wrote:
> 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.

I should have mentioned that I tried other time stamps, generated the
same way as "q" above. They did not fail the is.na() test. I think
that is.na() is doing a as.double() somewhere in there because
as.double(q)  gives  NA as a result.

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



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Maranatha! <><
John McKown