PeriodYearQuarterMonthWeekDayHourMinuteSecondMillisecondMicrosecondNanosecond

Period types represent discrete, human representations of time.

CompoundPeriod

ACompoundPeriod is useful for expressing time periods that are not a fixed multiple of smaller periods. For example, "a year and a day" is not a fixed number of days, but can be expressed using aCompoundPeriod. In fact, aCompoundPeriod is automatically generated by addition of different period types, e.g.Year(1) + Day(1) produces aCompoundPeriod result.

Instant

Instant types represent integer-based, machine representations of time as continuous timelines starting from an epoch.

UTInstant{T}

TheUTInstant represents a machine timeline based on UT time (1 day = one revolution of the earth). TheT is aPeriod parameter that indicates the resolution or precision of the instant.

TimeType

TimeType types wrapInstant machine instances to provide human representations of the machine instant.Time,DateTime andDate are subtypes ofTimeType.

DateTime

DateTime represents a point in time according to the proleptic Gregorian calendar. The finest resolution of the time is millisecond (i.e., microseconds or nanoseconds cannot be represented by this type). The type supports fixed-point arithmetic, and thus is prone to underflowing (and overflowing). A notable consequence is rounding when adding aMicrosecond or aNanosecond:

julia> dt = DateTime(2023, 8, 19, 17, 45, 32, 900)2023-08-19T17:45:32.900julia> dt + Millisecond(1)2023-08-19T17:45:32.901julia> dt + Microsecond(1000) # 1000us == 1ms2023-08-19T17:45:32.901julia> dt + Microsecond(999) # 999us rounded to 1000us2023-08-19T17:45:32.901julia> dt + Microsecond(1499) # 1499 rounded to 1000us2023-08-19T17:45:32.901

Date

Date wraps aUTInstant{Day} and interprets it according to the proleptic Gregorian calendar.

Time

Time wraps aNanosecond and represents a specific moment in a 24-hour day.

TimeZone

Geographic zone generally based on longitude determining what the time is at a certain location. Some time zones observe daylight savings (eg EST -> EDT). For implementations and more support, see theTimeZones.jl package

UTC

UTC, or Coordinated Universal Time, is theTimeZone from which all others are measured. It is associated with the time at 0° longitude. It is not adjusted for daylight savings.

DateTime(y, [m, d, h, mi, s, ms]) -> DateTime

Construct aDateTime type by parts. Arguments must be convertible toInt64.

DateTime(periods::Period...) -> DateTime

Construct aDateTime type byPeriod type parts. Arguments may be in any order. DateTime parts not provided will default to the value ofDates.default(period).

DateTime(f::Function, y[, m, d, h, mi, s]; step=Day(1), limit=10000) -> DateTime

Create aDateTime through the adjuster API. The starting point will be constructed from the providedy, m, d... arguments, and will be adjusted untilf::Function returnstrue. The step size in adjusting can be provided manually through thestep keyword.limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (in the case thatf::Function is never satisfied).

Examples

julia> DateTime(dt -> second(dt) == 40, 2010, 10, 20, 10; step = Second(1))2010-10-20T10:00:40julia> DateTime(dt -> hour(dt) == 20, 2010, 10, 20, 10; step = Hour(1), limit = 5)ERROR: ArgumentError: Adjustment limit reached: 5 iterationsStacktrace:[...]

DateTime(dt::Date) -> DateTime

Convert aDate to aDateTime. The hour, minute, second, and millisecond parts of the newDateTime are assumed to be zero.

DateTime(dt::AbstractString, format::AbstractString; locale="english") -> DateTime

Construct aDateTime by parsing thedt date time string following the pattern given in theformat string (seeDateFormat for syntax).

Examples

julia> DateTime("2020-01-01", "yyyy-mm-dd")2020-01-01T00:00:00julia> a = ("2020-01-01", "2020-01-02");julia> [DateTime(d, dateformat"yyyy-mm-dd") for d ∈ a] # preferred2-element Vector{DateTime}: 2020-01-01T00:00:00 2020-01-02T00:00:00

format(dt::TimeType, format::AbstractString; locale="english") -> AbstractString

Construct a string by using aTimeType object and applying the providedformat. The following character codes can be used to construct theformat string:

The number of sequential code characters indicate the width of the code. A format ofyyyy-mm specifies that the codey should have a width of four whilem a width of two. Codes that yield numeric digits have an associated mode: fixed-width or minimum-width. The fixed-width mode left-pads the value with zeros when it is shorter than the specified width and truncates the value when longer. Minimum-width mode works the same as fixed-width except that it does not truncate values longer than the width.

When creating aformat you can use any non-code characters as a separator. For example to generate the string "1996-01-15T00:00:00" you could useformat: "yyyy-mm-ddTHH:MM:SS". Note that if you need to use a code character as a literal you can use the escape character backslash. The string "1996y01m" can be produced with the format raw"yyyy\ymm\m".

DateFormat(format::AbstractString, locale="english") -> DateFormat

Construct a date formatting object that can be used for parsing date strings or formatting a date object as a string. The following character codes can be used to construct theformat string:

Characters not listed above are normally treated as delimiters between date and time slots. For example adt string of "1996-01-15T00:00:00.0" would have aformat string like "y-m-dTH:M:S.s". If you need to use a code character as a delimiter you can escape it using backslash. The date "1995y01m" would have the format "y\ym\m".

Note that 12:00AM corresponds 00:00 (midnight), and 12:00PM corresponds to 12:00 (noon). When parsing a time with ap specifier, any hour (eitherH orI) is interpreted as as a 12-hour clock, so theI code is mainly useful for output.

Creating a DateFormat object is expensive. Whenever possible, create it once and use it many times or try thedateformat"" string macro. Using this macro creates the DateFormat object once at macro expansion time and reuses it later. There are also severalpre-defined formatters, listed later.

SeeDateTime andformat for how to use a DateFormat object to parse and write Date strings respectively.

dateformat"Y-m-d H:M:S"

Create aDateFormat object. Similar toDateFormat("Y-m-d H:M:S") but creates the DateFormat object once during macro expansion.

SeeDateFormat for details about format specifiers.

DateTime(dt::AbstractString, df::DateFormat=ISODateTimeFormat) -> DateTime

Construct aDateTime by parsing thedt date time string following the pattern given in theDateFormat object, or dateformat"yyyy-mm-dd\THH:MM:SS.s" if omitted.

Similar toDateTime(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted date time strings with a pre-createdDateFormat object.

Date(y, [m, d]) -> Date

Construct aDate type by parts. Arguments must be convertible toInt64.

Date(period::Period...) -> Date

Construct aDate type byPeriod type parts. Arguments may be in any order.Date parts not provided will default to the value ofDates.default(period).

Date(f::Function, y[, m, d]; step=Day(1), limit=10000) -> Date

Create aDate through the adjuster API. The starting point will be constructed from the providedy, m, d arguments, and will be adjusted untilf::Function returnstrue. The step size in adjusting can be provided manually through thestep keyword.limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (given thatf::Function is never satisfied).

Examples

julia> Date(date -> week(date) == 20, 2010, 01, 01)2010-05-17julia> Date(date -> year(date) == 2010, 2000, 01, 01)2010-01-01julia> Date(date -> month(date) == 10, 2000, 01, 01; limit = 5)ERROR: ArgumentError: Adjustment limit reached: 5 iterationsStacktrace:[...]

Date(dt::DateTime) -> Date

Convert aDateTime to aDate. The hour, minute, second, and millisecond parts of theDateTime are truncated, so only the year, month and day parts are used in construction.

Date(d::AbstractString, format::AbstractString; locale="english") -> Date

Construct aDate by parsing thed date string following the pattern given in theformat string (seeDateFormat for syntax).

Examples

julia> Date("2020-01-01", "yyyy-mm-dd")2020-01-01julia> a = ("2020-01-01", "2020-01-02");julia> [Date(d, dateformat"yyyy-mm-dd") for d ∈ a] # preferred2-element Vector{Date}: 2020-01-01 2020-01-02

Date(d::AbstractString, df::DateFormat=ISODateFormat) -> Date

Construct aDate by parsing thed date string following the pattern given in theDateFormat object, or dateformat"yyyy-mm-dd" if omitted.

Similar toDate(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted date strings with a pre-createdDateFormat object.

Time(h, [mi, s, ms, us, ns]) -> Time

Construct aTime type by parts. Arguments must be convertible toInt64.

Time(period::TimePeriod...) -> Time

Construct aTime type byPeriod type parts. Arguments may be in any order.Time parts not provided will default to the value ofDates.default(period).

Time(f::Function, h, mi=0; step::Period=Second(1), limit::Int=10000)Time(f::Function, h, mi, s; step::Period=Millisecond(1), limit::Int=10000)Time(f::Function, h, mi, s, ms; step::Period=Microsecond(1), limit::Int=10000)Time(f::Function, h, mi, s, ms, us; step::Period=Nanosecond(1), limit::Int=10000)

Create aTime through the adjuster API. The starting point will be constructed from the providedh, mi, s, ms, us arguments, and will be adjusted untilf::Function returnstrue. The step size in adjusting can be provided manually through thestep keyword.limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (in the case thatf::Function is never satisfied). Note that the default step will adjust to allow for greater precision for the given arguments; i.e. if hour, minute, and second arguments are provided, the default step will beMillisecond(1) instead ofSecond(1).

Examples

julia> Time(t -> minute(t) == 30, 20)20:30:00julia> Time(t -> minute(t) == 0, 20)20:00:00julia> Time(t -> hour(t) == 10, 3; limit = 5)ERROR: ArgumentError: Adjustment limit reached: 5 iterationsStacktrace:[...]

Time(dt::DateTime) -> Time

Convert aDateTime to aTime. The hour, minute, second, and millisecond parts of theDateTime are used to create the newTime. Microsecond and nanoseconds are zero by default.

Time(t::AbstractString, format::AbstractString; locale="english") -> Time

Construct aTime by parsing thet time string following the pattern given in theformat string (seeDateFormat for syntax).

Examples

julia> Time("12:34pm", "HH:MMp")12:34:00julia> a = ("12:34pm", "2:34am");julia> [Time(d, dateformat"HH:MMp") for d ∈ a] # preferred2-element Vector{Time}: 12:34:00 02:34:00

Time(t::AbstractString, df::DateFormat=ISOTimeFormat) -> Time

Construct aTime by parsing thet date time string following the pattern given in theDateFormat object, or dateformat"HH:MM:SS.s" if omitted.

Similar toTime(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted time strings with a pre-createdDateFormat object.

now() -> DateTime

Return aDateTime corresponding to the user's system time including the system timezone locale.

now(::Type{UTC}) -> DateTime

Return aDateTime corresponding to the user's system time as UTC/GMT. For other time zones, see the TimeZones.jl package.

Examples

julia> now(UTC)2023-01-04T10:52:24.864

eps(::Type{DateTime}) -> Millisecondeps(::Type{Date}) -> Dayeps(::Type{Time}) -> Nanosecondeps(::TimeType) -> Period

Return the smallest unit value supported by theTimeType.

Examples

julia> eps(DateTime)1 millisecondjulia> eps(Date)1 dayjulia> eps(Time)1 nanosecond

year(dt::TimeType) -> Int64

The year of aDate orDateTime as anInt64.

month(dt::TimeType) -> Int64

The month of aDate orDateTime as anInt64.

week(dt::TimeType) -> Int64

Return theISO week date of aDate orDateTime as anInt64. Note that the first week of a year is the week that contains the first Thursday of the year, which can result in dates prior to January 4th being in the last week of the previous year. For example,week(Date(2005, 1, 1)) is the 53rd week of 2004.

Examples

julia> week(Date(1989, 6, 22))25julia> week(Date(2005, 1, 1))53julia> week(Date(2004, 12, 31))53

day(dt::TimeType) -> Int64

The day of month of aDate orDateTime as anInt64.

hour(dt::DateTime) -> Int64

The hour of day of aDateTime as anInt64.

hour(t::Time) -> Int64

The hour of aTime as anInt64.

minute(dt::DateTime) -> Int64

The minute of aDateTime as anInt64.

minute(t::Time) -> Int64

The minute of aTime as anInt64.

second(dt::DateTime) -> Int64

The second of aDateTime as anInt64.

second(t::Time) -> Int64

The second of aTime as anInt64.

millisecond(dt::DateTime) -> Int64

The millisecond of aDateTime as anInt64.

millisecond(t::Time) -> Int64

The millisecond of aTime as anInt64.

microsecond(t::Time) -> Int64

The microsecond of aTime as anInt64.

nanosecond(t::Time) -> Int64

The nanosecond of aTime as anInt64.

Year(v)

Construct aYear object with the givenv value. Input must be losslessly convertible to anInt64.

Month(v)

Construct aMonth object with the givenv value. Input must be losslessly convertible to anInt64.

Week(v)

Construct aWeek object with the givenv value. Input must be losslessly convertible to anInt64.

Day(v)

Construct aDay object with the givenv value. Input must be losslessly convertible to anInt64.

Hour(dt::DateTime) -> Hour

The hour part of a DateTime as aHour.

Minute(dt::DateTime) -> Minute

The minute part of a DateTime as aMinute.

Second(dt::DateTime) -> Second

The second part of a DateTime as aSecond.

Millisecond(dt::DateTime) -> Millisecond

The millisecond part of a DateTime as aMillisecond.

Microsecond(dt::Time) -> Microsecond

The microsecond part of a Time as aMicrosecond.

Nanosecond(dt::Time) -> Nanosecond

The nanosecond part of a Time as aNanosecond.

yearmonth(dt::TimeType) -> (Int64, Int64)

Simultaneously return the year and month parts of aDate orDateTime.

monthday(dt::TimeType) -> (Int64, Int64)

Simultaneously return the month and day parts of aDate orDateTime.

yearmonthday(dt::TimeType) -> (Int64, Int64, Int64)

Simultaneously return the year, month and day parts of aDate orDateTime.

dayname(dt::TimeType; locale="english") -> Stringdayname(day::Integer; locale="english") -> String

Return the full day name corresponding to the day of the week of theDate orDateTime in the givenlocale. Also acceptsInteger.

Examples

julia> dayname(Date("2000-01-01"))"Saturday"julia> dayname(4)"Thursday"

dayabbr(dt::TimeType; locale="english") -> Stringdayabbr(day::Integer; locale="english") -> String

Return the abbreviated name corresponding to the day of the week of theDate orDateTime in the givenlocale. Also acceptsInteger.

Examples

julia> dayabbr(Date("2000-01-01"))"Sat"julia> dayabbr(3)"Wed"

dayofweek(dt::TimeType) -> Int64

Return the day of the week as anInt64 with1 = Monday, 2 = Tuesday, etc..

Examples

julia> dayofweek(Date("2000-01-01"))6

dayofmonth(dt::TimeType) -> Int64

The day of month of aDate orDateTime as anInt64.

dayofweekofmonth(dt::TimeType) -> Int

For the day of week ofdt, return which number it is indt's month. So if the day of the week ofdt is Monday, then1 = First Monday of the month, 2 = Second Monday of the month, etc. In the range 1:5.

Examples

julia> dayofweekofmonth(Date("2000-02-01"))1julia> dayofweekofmonth(Date("2000-02-08"))2julia> dayofweekofmonth(Date("2000-02-15"))3

daysofweekinmonth(dt::TimeType) -> Int

For the day of week ofdt, return the total number of that day of the week indt's month. Returns 4 or 5. Useful in temporal expressions for specifying the last day of a week in a month by includingdayofweekofmonth(dt) == daysofweekinmonth(dt) in the adjuster function.

Examples

julia> daysofweekinmonth(Date("2005-01-01"))5julia> daysofweekinmonth(Date("2005-01-04"))4

monthname(dt::TimeType; locale="english") -> Stringmonthname(month::Integer, locale="english") -> String

Return the full name of the month of theDate orDateTime orInteger in the givenlocale.

Examples

julia> monthname(Date("2005-01-04"))"January"julia> monthname(2)"February"

monthabbr(dt::TimeType; locale="english") -> Stringmonthabbr(month::Integer, locale="english") -> String

Return the abbreviated month name of theDate orDateTime orInteger in the givenlocale.

Examples

julia> monthabbr(Date("2005-01-04"))"Jan"julia> monthabbr(2)"Feb"

daysinmonth(dt::TimeType) -> Int

Return the number of days in the month ofdt. Value will be 28, 29, 30, or 31.

Examples

julia> daysinmonth(Date("2000-01"))31julia> daysinmonth(Date("2001-02"))28julia> daysinmonth(Date("2000-02"))29

isleapyear(dt::TimeType) -> Bool

Returntrue if the year ofdt is a leap year.

Examples

julia> isleapyear(Date("2004"))truejulia> isleapyear(Date("2005"))false

dayofyear(dt::TimeType) -> Int

Return the day of the year fordt with January 1st being day 1.

daysinyear(dt::TimeType) -> Int

Return 366 if the year ofdt is a leap year, otherwise return 365.

Examples

julia> daysinyear(1999)365julia> daysinyear(2000)366

quarterofyear(dt::TimeType) -> Int

Return the quarter thatdt resides in. Range of value is 1:4.

dayofquarter(dt::TimeType) -> Int

Return the day of the current quarter ofdt. Range of value is 1:92.

trunc(dt::TimeType, ::Type{Period}) -> TimeType

Truncates the value ofdt according to the providedPeriod type.

Examples

julia> trunc(DateTime("1996-01-01T12:30:00"), Day)1996-01-01T00:00:00

firstdayofweek(dt::TimeType) -> TimeType

Adjustsdt to the Monday of its week.

Examples

julia> firstdayofweek(DateTime("1996-01-05T12:30:00"))1996-01-01T00:00:00

lastdayofweek(dt::TimeType) -> TimeType

Adjustsdt to the Sunday of its week.

Examples

julia> lastdayofweek(DateTime("1996-01-05T12:30:00"))1996-01-07T00:00:00

firstdayofmonth(dt::TimeType) -> TimeType

Adjustsdt to the first day of its month.

Examples

julia> firstdayofmonth(DateTime("1996-05-20"))1996-05-01T00:00:00

lastdayofmonth(dt::TimeType) -> TimeType

Adjustsdt to the last day of its month.

Examples

julia> lastdayofmonth(DateTime("1996-05-20"))1996-05-31T00:00:00

firstdayofyear(dt::TimeType) -> TimeType

Adjustsdt to the first day of its year.

Examples

julia> firstdayofyear(DateTime("1996-05-20"))1996-01-01T00:00:00

lastdayofyear(dt::TimeType) -> TimeType

Adjustsdt to the last day of its year.

Examples

julia> lastdayofyear(DateTime("1996-05-20"))1996-12-31T00:00:00

firstdayofquarter(dt::TimeType) -> TimeType

Adjustsdt to the first day of its quarter.

Examples

julia> firstdayofquarter(DateTime("1996-05-20"))1996-04-01T00:00:00julia> firstdayofquarter(DateTime("1996-08-20"))1996-07-01T00:00:00

lastdayofquarter(dt::TimeType) -> TimeType

Adjustsdt to the last day of its quarter.

Examples

julia> lastdayofquarter(DateTime("1996-05-20"))1996-06-30T00:00:00julia> lastdayofquarter(DateTime("1996-08-20"))1996-09-30T00:00:00

tonext(dt::TimeType, dow::Int; same::Bool=false) -> TimeType

Adjustsdt to the next day of week corresponding todow with1 = Monday, 2 = Tuesday, etc. Settingsame=true allows the currentdt to be considered as the nextdow, allowing for no adjustment to occur.

toprev(dt::TimeType, dow::Int; same::Bool=false) -> TimeType

Adjustsdt to the previous day of week corresponding todow with1 = Monday, 2 = Tuesday, etc. Settingsame=true allows the currentdt to be considered as the previousdow, allowing for no adjustment to occur.

tofirst(dt::TimeType, dow::Int; of=Month) -> TimeType

Adjustsdt to the firstdow of its month. Alternatively,of=Year will adjust to the firstdow of the year.

tolast(dt::TimeType, dow::Int; of=Month) -> TimeType

Adjustsdt to the lastdow of its month. Alternatively,of=Year will adjust to the lastdow of the year.

tonext(func::Function, dt::TimeType; step=Day(1), limit=10000, same=false) -> TimeType

Adjustsdt by iterating at mostlimit iterations bystep increments untilfunc returnstrue.func must take a singleTimeType argument and return aBool.same allowsdt to be considered in satisfyingfunc.

toprev(func::Function, dt::TimeType; step=Day(-1), limit=10000, same=false) -> TimeType

Adjustsdt by iterating at mostlimit iterations bystep increments untilfunc returnstrue.func must take a singleTimeType argument and return aBool.same allowsdt to be considered in satisfyingfunc.

Year(v)Quarter(v)Month(v)Week(v)Day(v)Hour(v)Minute(v)Second(v)Millisecond(v)Microsecond(v)Nanosecond(v)

Construct aPeriod type with the givenv value. Input must be losslessly convertible to anInt64.

CompoundPeriod(periods) -> CompoundPeriod

Construct aCompoundPeriod from aVector ofPeriods. AllPeriods of the same type will be added together.

Examples

julia> Dates.CompoundPeriod(Dates.Hour(12), Dates.Hour(13))25 hoursjulia> Dates.CompoundPeriod(Dates.Hour(-1), Dates.Minute(1))-1 hour, 1 minutejulia> Dates.CompoundPeriod(Dates.Month(1), Dates.Week(-2))1 month, -2 weeksjulia> Dates.CompoundPeriod(Dates.Minute(50000))50000 minutes

canonicalize(::CompoundPeriod) -> CompoundPeriod

Reduces theCompoundPeriod into its canonical form by applying the following rules:

• AnyPeriod large enough be partially representable by a coarserPeriod will be broken into multiplePeriods (eg.Hour(30) becomesDay(1) + Hour(6))
• Periods with opposite signs will be combined when possible (eg.Hour(1) - Day(1) becomes-Hour(23))

Examples

julia> canonicalize(Dates.CompoundPeriod(Dates.Hour(12), Dates.Hour(13)))1 day, 1 hourjulia> canonicalize(Dates.CompoundPeriod(Dates.Hour(-1), Dates.Minute(1)))-59 minutesjulia> canonicalize(Dates.CompoundPeriod(Dates.Month(1), Dates.Week(-2)))1 month, -2 weeksjulia> canonicalize(Dates.CompoundPeriod(Dates.Minute(50000)))4 weeks, 6 days, 17 hours, 20 minutes

Dates.value(x::Period) -> Int64

For a given period, return the value associated with that period. For example,value(Millisecond(10)) returns 10 as an integer.

default(p::Period) -> Period

Return a sensible "default" value for the input Period by returningT(1) for Year, Month, and Day, andT(0) for Hour, Minute, Second, and Millisecond.

Dates.periods(::CompoundPeriod) -> Vector{Period}

Return theVector ofPeriods that comprise the givenCompoundPeriod.

floor(dt::TimeType, p::Period) -> TimeType

Return the nearestDate orDateTime less than or equal todt at resolutionp.

For convenience,p may be a type instead of a value:floor(dt, Dates.Hour) is a shortcut forfloor(dt, Dates.Hour(1)).

julia> floor(Date(1985, 8, 16), Month)1985-08-01julia> floor(DateTime(2013, 2, 13, 0, 31, 20), Minute(15))2013-02-13T00:30:00julia> floor(DateTime(2016, 8, 6, 12, 0, 0), Day)2016-08-06T00:00:00

ceil(dt::TimeType, p::Period) -> TimeType

Return the nearestDate orDateTime greater than or equal todt at resolutionp.

For convenience,p may be a type instead of a value:ceil(dt, Dates.Hour) is a shortcut forceil(dt, Dates.Hour(1)).

julia> ceil(Date(1985, 8, 16), Month)1985-09-01julia> ceil(DateTime(2013, 2, 13, 0, 31, 20), Minute(15))2013-02-13T00:45:00julia> ceil(DateTime(2016, 8, 6, 12, 0, 0), Day)2016-08-07T00:00:00

round(dt::TimeType, p::Period, [r::RoundingMode]) -> TimeType

Return theDate orDateTime nearest todt at resolutionp. By default (RoundNearestTiesUp), ties (e.g., rounding 9:30 to the nearest hour) will be rounded up.

For convenience,p may be a type instead of a value:round(dt, Dates.Hour) is a shortcut forround(dt, Dates.Hour(1)).

julia> round(Date(1985, 8, 16), Month)1985-08-01julia> round(DateTime(2013, 2, 13, 0, 31, 20), Minute(15))2013-02-13T00:30:00julia> round(DateTime(2016, 8, 6, 12, 0, 0), Day)2016-08-07T00:00:00

Valid rounding modes forround(::TimeType, ::Period, ::RoundingMode) areRoundNearestTiesUp (default),RoundDown (floor), andRoundUp (ceil).

floor(x::Period, precision::T) where T <: Union{TimePeriod, Week, Day} -> T

Roundx down to the nearest multiple ofprecision. Ifx andprecision are different subtypes ofPeriod, the return value will have the same type asprecision.

For convenience,precision may be a type instead of a value:floor(x, Dates.Hour) is a shortcut forfloor(x, Dates.Hour(1)).

julia> floor(Day(16), Week)2 weeksjulia> floor(Minute(44), Minute(15))30 minutesjulia> floor(Hour(36), Day)1 day

Rounding to aprecision ofMonths orYears is not supported, as thesePeriods are of inconsistent length.

ceil(x::Period, precision::T) where T <: Union{TimePeriod, Week, Day} -> T

Roundx up to the nearest multiple ofprecision. Ifx andprecision are different subtypes ofPeriod, the return value will have the same type asprecision.

For convenience,precision may be a type instead of a value:ceil(x, Dates.Hour) is a shortcut forceil(x, Dates.Hour(1)).

julia> ceil(Day(16), Week)3 weeksjulia> ceil(Minute(44), Minute(15))45 minutesjulia> ceil(Hour(36), Day)2 days

Rounding to aprecision ofMonths orYears is not supported, as thesePeriods are of inconsistent length.

round(x::Period, precision::T, [r::RoundingMode]) where T <: Union{TimePeriod, Week, Day} -> T

Roundx to the nearest multiple ofprecision. Ifx andprecision are different subtypes ofPeriod, the return value will have the same type asprecision. By default (RoundNearestTiesUp), ties (e.g., rounding 90 minutes to the nearest hour) will be rounded up.

For convenience,precision may be a type instead of a value:round(x, Dates.Hour) is a shortcut forround(x, Dates.Hour(1)).

julia> round(Day(16), Week)2 weeksjulia> round(Minute(44), Minute(15))45 minutesjulia> round(Hour(36), Day)2 days

Valid rounding modes forround(::Period, ::T, ::RoundingMode) areRoundNearestTiesUp (default),RoundDown (floor), andRoundUp (ceil).

Rounding to aprecision ofMonths orYears is not supported, as thesePeriods are of inconsistent length.

floorceil(dt::TimeType, p::Period) -> (TimeType, TimeType)

Simultaneously return thefloor andceil of aDate orDateTime at resolutionp. More efficient than calling bothfloor andceil individually.

floorceil(x::Period, precision::T) where T <: Union{TimePeriod, Week, Day} -> (T, T)

Simultaneously return thefloor andceil ofPeriod at resolutionp. More efficient than calling bothfloor andceil individually.

epochdays2date(days) -> Date

Take the number of days since the rounding epoch (0000-01-01T00:00:00) and return the correspondingDate.

epochms2datetime(milliseconds) -> DateTime

Take the number of milliseconds since the rounding epoch (0000-01-01T00:00:00) and return the correspondingDateTime.

date2epochdays(dt::Date) -> Int64

Take the givenDate and return the number of days since the rounding epoch (0000-01-01T00:00:00) as anInt64.

datetime2epochms(dt::DateTime) -> Int64

Take the givenDateTime and return the number of milliseconds since the rounding epoch (0000-01-01T00:00:00) as anInt64.

today() -> Date

Return the date portion ofnow().

unix2datetime(x) -> DateTime

Take the number of seconds since unix epoch1970-01-01T00:00:00 and convert to the correspondingDateTime.

datetime2unix(dt::DateTime) -> Float64

Take the givenDateTime and return the number of seconds since the unix epoch1970-01-01T00:00:00 as aFloat64.

julian2datetime(julian_days) -> DateTime

Take the number of Julian calendar days since epoch-4713-11-24T12:00:00 and return the correspondingDateTime.

datetime2julian(dt::DateTime) -> Float64

Take the givenDateTime and return the number of Julian calendar days since the julian epoch-4713-11-24T12:00:00 as aFloat64.

rata2datetime(days) -> DateTime

Take the number of Rata Die days since epoch0000-12-31T00:00:00 and return the correspondingDateTime.

datetime2rata(dt::TimeType) -> Int64

Return the number of Rata Die days since epoch from the givenDate orDateTime.

Dates.ISODateTimeFormat

Describes the ISO8601 formatting for a date and time. This is the default value forDates.format of aDateTime.

Examples

julia> Dates.format(DateTime(2018, 8, 8, 12, 0, 43, 1), ISODateTimeFormat)"2018-08-08T12:00:43.001"

Dates.ISODateFormat

Describes the ISO8601 formatting for a date. This is the default value forDates.format of aDate.

Examples

julia> Dates.format(Date(2018, 8, 8), ISODateFormat)"2018-08-08"

Dates.ISOTimeFormat

Describes the ISO8601 formatting for a time. This is the default value forDates.format of aTime.

Examples

julia> Dates.format(Time(12, 0, 43, 1), ISOTimeFormat)"12:00:43.001"

Dates.RFC1123Format

Describes the RFC1123 formatting for a date and time.

Examples

julia> Dates.format(DateTime(2018, 8, 8, 12, 0, 43, 1), RFC1123Format)"Wed, 08 Aug 2018 12:00:43"