Function reference • lubridate

Date/time parsing

ymd() ydm() mdy() myd() dmy() dym() yq() ym() my(): 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<-`() `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

as_date() as_datetime(): Convert an object to a date or date-time

cyclic_encoding(): Cyclic encoding of date-times

date() `date<-`(): Get/set date component of a date-time

decimal_date(): Converts a date to a decimal of its year

is.Date() Date() NA_Date_: Various date utilities

is.POSIXt() is.POSIXlt() is.POSIXct() POSIXct() NA_POSIXct_: Various POSIX utilities

is.instant() is.timepoint(): Is x a date-time object?

make_datetime() make_date(): Efficient creation of date-times from numeric representations

now() today(): The current day and time

origin: 1970-01-01 UTC

Durations

A ‘duration’ is a timespan measured in seconds.

duration() dseconds() dminutes() dhours() ddays() dweeks() dmonths() 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

Duration-class durations: Duration class

Periods

A ‘period’ is a timespan defined in civil time (human) units like years, months, and days.

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

as.period(): Change an object to a period

Period-class: Period class

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%`: Does a date (or interval) fall within an interval?

Interval-class intervals: Interval class

Timespans

Timespans are the generic concept that underlies durations, periods, and intervals.

timespan timespans: 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?

Formatters

stamp() stamp_date() stamp_time(): Format dates and times based on human-friendly templates

format_ISO8601(): Format in ISO8601 character format

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

rollbackward() rollback() rollforward(): Roll backward or forward a date the previous, current or next month

`%m+%` add_with_rollback(): Add and subtract months to a date without exceeding the last day of the new month

local_time(): Get local time from a date-time vector.

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?

date_decimal(): Converts a decimal to a date

Data

lakers: Lakers 2008-2009 basketball data set