difftime.days: Compute Time Difference In Days
In benjaminrich/PCSmisc: Useful functions for longitudinal data set construction and manipulation.

Description Usage Arguments Details Value Author(s) See Also Examples

Computes the number of days between two vectors of class Date or POSIXt. In the latter case, the time portion is ignored.

1	difftime.days(time1, time2)

time1, time2

Two vectors of the same length, both either of class Date or POSIXt.

This function considers the calendar date portion of a POSIXt object only. Thus, a day need not correspond to a 24 hour period (see example).

An integer vector containing the number of days between time1 and time2.

Ben Rich <[email protected]>

difftime.default difftime

## Not run: 
time1 <- strptime("2011-12-22 00:03", "
time2 <- strptime("2011-12-22 00:01", "
time3 <- strptime("2011-12-21 23:59", "
time4 <- strptime("2011-12-20 00:01", "
difftime.days(time1, time2)  # 2 minutes difference, on the same day so considered 0 days 
difftime.days(time2, time3)  # Also 2 minutes difference but on different days, so considered one day
difftime.days(time3, time4)  # Although only 47 hours and 58 minutes difference, still considered one day

## End(Not run)