timespan {lubridate}

Description of time span classes in lubridate

Description

A time span can be measured in three ways: as a duration, an interval, or a period.

• durations record the exact number of seconds in a time span. They measure the exact passage of time but do not always align with human measurements like hours, months and years.

• periods record the change in the clock time between two date-times. They are measured in human units: years, months, days, hours, minutes, and seconds.

• intervals are time spans bound by two real date-times. Intervals can be accurately converted to periods and durations.

Examples

duration(3690, "seconds")
period(3690, "seconds")
period(second = 30, minute = 1, hour = 1)
interval(ymd_hms("2009-08-09 13:01:30"), ymd_hms("2009-08-09 12:00:00"))

date <- ymd_hms("2009-03-08 01:59:59") # DST boundary
date + days(1)
date + ddays(1)

date2 <- ymd_hms("2000-02-29 12:00:00")
date2 + years(1)
# self corrects to next real day

date3 <- ymd_hms("2009-01-31 01:00:00")
date3 + c(0:11) * months(1)

span <- date2 %--% date # creates interval

date <- ymd_hms("2009-01-01 00:00:00")
date + years(1)
date - days(3) + hours(6)
date + 3 * seconds(10)

months(6) + days(1)