new_interval: Create an interval object.

Description

Create an interval object.

Usage

new_interval(date2, date1)

Arguments

date1

a POSIXt or Date date-time object

date2

a POSIXt or Date date-time object

Value

an interval object

Details

new_interval creates an interval object with the specified start and end dates. new_interval automatically assigns the date that occurs first in time as the start date and the date that occurs later as the end date. As a result, intervals are always positive.

Intervals are time spans bound by two real date-times. Intervals can be accurately converted to either period or duration objects using as.period, as.duration. Since an interval is anchored to a fixed history of time, both the exact number of seconds that passed and the number of variable length time units that occurred during the interval can be calculated. Subtracting two date times automatically creates an interval object.

Examples

Run this code

new_interval(ymd(20090201), ymd(20090101))
# 2009-01-01 -- 2009-02-01 

date1 <- as.POSIXct("2009-03-08 01:59:59")
date2 <- as.POSIXct("2000-02-29 12:00:00")
new_interval(date2, date1)
# 2000-02-29 12:00:00 -- 2009-03-08 01:59:59
new_interval(date1, date2)
# 2000-02-29 12:00:00 -- 2009-03-08 01:59:59

span <- new_interval(ymd(20090201), ymd(20090101))
# [1] 2009-01-01 -- 2009-02-01 
span - days(30)
# 2009-01-01 -- 2009-01-02
span + months(6)
# 2009-01-01 -- 2009-08-01 

start <- attr(span, "start")
# "2009-01-01 UTC"
end <- start + span
# "2009-02-01 UTC"}