Function reference • lubridate

Date/time parsing
`ymd()` `ydm()` `mdy()` `myd()` `dmy()` `dym()` `yq()`	Parse dates with year, month, and day components
`ymd_hms()` `ymd_hm()` `ymd_h()` `dmy_hms()` `dmy_hm()` `dmy_h()` `mdy_hms()` `mdy_hm()` `mdy_h()` `ydm_hms()` `ydm_hm()` `ydm_h()`	Parse date-times with year, month, and day, hour, minute, and second components.
`ms()` `hm()` `hms()`	Parse periods with hour, minute, and second components
`parse_date_time()` `parse_date_time2()` `fast_strptime()`	User friendly date-time parsing functions
`guess_formats()`	Guess possible date-times formats from a character vector
Setting, getting, and rounding
`year()` `year<-`() `isoyear()` `epiyear()`	Get/set years component of a date-time
`quarter()` `semester()`	Get the fiscal quarter and semester of a date-time
`month()` `month<-`()	Get/set months component of a date-time
`week()` `week<-`() `isoweek()` `epiweek()`	Get/set weeks component of a date-time
`day()` `mday()` `wday()` `qday()` `yday()` `day<-`() `mday<-`() `qday<-`() `wday<-`() `yday<-`()	Get/set days component of a date-time
`hour()` `hour<-`()	Get/set hours component of a date-time
`minute()` `minute<-`()	Get/set minutes component of a date-time
`second()` `second<-`()	Get/set seconds component of a date-time
`tz()` `tz<-`()	Get/set time zone component of a date-time
Date-time helpers
`make_datetime()` `make_date()`	Efficient creation of date-times from numeric representations
`date()` `date<-`()	Get/set date component of a date-time
`is.instant()` `is.timepoint()`	Is x a date-time object?
`is.Date()`	Is x a Date object?
`is.POSIXt()` `is.POSIXlt()` `is.POSIXct()`	Is x a POSIXct or POSIXlt object?
`now()`	The current time
`today()`	The current date
`origin`	1970-01-01 UTC
`decimal_date()`	Converts a date to a decimal of its year
`as_date()` `as_datetime()`	Convert an object to a date or date-time
Durations A period is a timespan measured in seconds.
`duration()` `dseconds()` `dminutes()` `dhours()` `ddays()` `dweeks()` `dyears()` `dmilliseconds()` `dmicroseconds()` `dnanoseconds()` `dpicoseconds()` `is.duration()`	Create a duration object.
`is.difftime()`	Is x a difftime object?
`make_difftime()`	Create a difftime object.
`as.duration()`	Change an object to a duration
Periods A period is a timespan defined by human units like years, months, and days.
`as.period()`	Change an object to a period
`period()` `is.period()` `seconds()` `minutes()` `hours()` `days()` `weeks()` `years()` `milliseconds()` `microseconds()` `nanoseconds()` `picoseconds()` `months(<numeric>)`	Create or parse period objects
`period_to_seconds()` `seconds_to_period()`	Contrive a period to/from a given number of seconds
Intervals An interval is a timespan defined by two date-times.
`interval()` `%--%` `is.interval()` `int_start()` `int_start<-`() `int_end()` `int_end<-`() `int_length()` `int_flip()` `int_shift()` `int_overlaps()` `int_standardize()` `int_aligns()` `int_diff()`	Utilities for creation and manipulation of `Interval` objects
`as.interval()`	Change an object to an `interval`
`%within%`	Tests whether a date or interval falls within an interval
Timespans Timespans are the generic concept that underlies durations, periods, and intervals.
`timespan`	Description of time span classes in lubridate
`time_length()`	Compute the exact length of a time span
`is.timespan()`	Is x a length of time?
Other modification functions
`update(<POSIXt>)`	Changes the components of a date object
`fit_to_timeline()`	Fit a POSIXlt date-time to the timeline
`with_tz()`	Get date-time in a different time zone
`force_tz()` `force_tzs()`	Replace time zone to create new date-time
`round_date()` `floor_date()` `ceiling_date()`	Round, floor and ceiling methods for date-time objects
`pretty_dates()`	Computes attractive axis breaks for date-time data
`rollback()`	Roll back date to last day of previous month
`%m+%` `add_with_rollback()`	Add and subtract months to a date without exceeding the last day of the new month
Other date-time components
`am()` `pm()`	Does date time occur in the am or pm?
`days_in_month()`	Get the number of days in the month of a date-time
`dst()`	Get daylight savings time indicator of a date-time
`leap_year()`	Is a year a leap year?
`stamp()` `stamp_date()` `stamp_time()`	Format dates and times based on human-friendly templates
`date_decimal()`	Converts a decimal to a date
Data
`lakers`	Lakers 2008-2009 basketball data set

Reference

Date/time parsing

Setting, getting, and rounding

Date-time helpers

Durations

Periods

Intervals

Timespans

Other modification functions

Other date-time components

Data

Contents