[R] Extract time only from POSIXlt object

Jeff Newmiller jdnewmil at dcn.davis.ca.us
Sun Jan 30 11:15:12 CET 2011


Try

tt <- as.POSIXct("2011-01-29 15:00")
tt-trunc(tt,"days")

Note that this result can be used to add or subtract from datetime values, but I don't know of a convenient way to represent it as HH:MM:SS format.

"Simon Goodman" <s.j.goodman at leeds.ac.uk> wrote:

>
>How can I extract only the time component from an POSIXlt object?
>
>For example if I try the following it still returns both the date and
>time...
>
>>as.POSIXlt(tr.date[1])
>[1] "2010-10-18 21:46:53"
>>as.POSIXlt(tr.date[1],"%H:%M:%S")
>[1] "2010-10-18 21:46:53"
>
>round and trunc don't help...  is there an "as.Time" equivalent to
>as.Date  
>?
>
>Thanks, Simon
>
>-- 
>View this message in context:
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>
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