[R] Units of Difference Between Two Dates

[Uwe Ligges]

Tom La Bone wrote:
> I would like all three of these calculations to give an answer in days (or at
> least the same units):
> 
>> as.POSIXct("1971-08-01 00:00:00") - as.POSIXct("1971-08-01 00:00:00")
> Time difference of 0 secs
>> as.POSIXct("1971-08-01 12:00:00") - as.POSIXct("1971-08-01 00:00:00")
> Time difference of 12 hours
>> as.POSIXct("1971-09-01 00:00:00") - as.POSIXct("1971-08-01 00:00:00")
> Time difference of 31 days
> 
> What is the best way to do this?
> 
> Tom
> 


  difftime(as.POSIXct("1971-08-01 00:00:00"), as.POSIXct("1971-08-01 
00:00:00"), units="days")

and so on ...

Uwe Ligges