[R] time conversions

[Troels Ring]

Thanks a lot and thanks to Rui
Troels

Den 18-02-2015 kl. 20:14 skrev peter dalgaard:
>> On 18 Feb 2015, at 18:45 , Troels Ring <tring at gvdnet.dk> wrote:
>>
>> dear friends - sorry to ask another simple question -
>> I have dates set up as this:
>> dates  #[1] 2003-01-21 01:08:00
>>
>> To handle it I did
>> as.POSIXlt(dates)  "2003-01-21 01:08:00 CET"
>>
>> but noticed that during write.table it was apparently better to take it further
>> as.numeric(as.POSIXct(as.POSIXlt(dates))   1043107680
>>
>> And this works fine for modeling but now I would like to have it back as POSIXlt
>> as.POSIXlt requires an origin, if I'm right.
>> So how is it done?
> Like this?
>
>> as.POSIXlt(1043107680, origin='1970-1-1')
> [1] "2003-01-21 01:08:00 CET"
>
> (Time zones may require special care, though.)
>