lubridate (version 1.6.0)

quick_periods: Quickly create period objects.

Description

Quickly create Period objects for easy date-time manipulation. The units of the period created depend on the name of the function called. For Period objects, units do not have a fixed length until they are added to a specific date time, contrast this with duration. This makes periods useful for manipulations with clock times because units expand or contract in length to accomodate conventions such as leap years, leap seconds, and Daylight Savings Time.

Usage

seconds(x = 1)

minutes(x = 1)

hours(x = 1)

days(x = 1)

weeks(x = 1)

years(x = 1)

milliseconds(x = 1)

microseconds(x = 1)

nanoseconds(x = 1)

picoseconds(x = 1)

# S3 method for numeric months(x, abbreviate)

Arguments

x

numeric value of the number of units to be contained in the period. With the exception of seconds(), x must be an integer.

abbreviate

Ignored. For consistency with S3 generic in base namespace.

Value

a period object

Details

When paired with date-times, these functions allow date-times to be manipulated in a method similar to object oriented programming. Period objects can be added to Date, POSIXct, and POSIXlt objects to calculate new date-times.

Note: Arithmetic with periods can results in undefined behavior when non-existent dates are involved (such as February 29th in non-leap years). Please see Period-class for more details and %m+% and add_with_rollback for alternative operations.

See Also

Period-class, period, ddays, %m+%, add_with_rollback

Examples

# NOT RUN {
x <- as.POSIXct("2009-08-03")
x + days(1) + hours(6) + minutes(30)
x + days(100) - hours(8)

class(as.Date("2009-08-09") + days(1)) # retains Date class
as.Date("2009-08-09") + hours(12)
class(as.Date("2009-08-09") + hours(12))
# converts to POSIXt class to accomodate time units

years(1) - months(7)
c(1:3) * hours(1)
hours(1:3)

#sequencing
y <- ymd(090101) # "2009-01-01 CST"
y + months(0:11)

# compare DST handling to durations
boundary <- as.POSIXct("2009-03-08 01:59:59")
boundary + days(1) # period
boundary + ddays(1) # duration
# seconds later)
# }