[R] changing date by +/- days

[Jeff Newmiller]

I try to use difftimes as much as possible.  For example,

oneday <- as.difftime( 24, units="hours" )
sometime - 10 * oneday

You might also find the lubridate package useful.
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Sent from my phone. Please excuse my brevity.

"chuck.01" <CharlieTheBrown77 at gmail.com> wrote:

>got it, sorry!
>
>structure(1243792800, class = c("POSIXct", "POSIXt"), tzone =
>"GMT")-(60*60*24*10)
>
>
>
>
>chuck.01 wrote
>> Hi, 
>> Let say I have a date variable like this:
>> 
>> structure(1243792800, class = c("POSIXct", "POSIXt"), tzone = "GMT")
>> [1] "2009-05-31 18:00:00 GMT"
>> 
>> How can I make it 10 days prior, so:
>> [1] "2009-05-21 18:00:00 GMT"
>> 
>> I'm randomly selecting dates from a list  and want a  second value a
>set #
>> of days either before or after. 
>> 
>> Thanks ahead of time.
>
>
>
>
>
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