Period
Year
Quarter
Month
Week
Day
Hour
Minute
Second
Millisecond
Microsecond
Nanosecond

Period types represent discrete, human representations of time.

CompoundPeriod

A CompoundPeriod 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 a CompoundPeriod. In fact, a CompoundPeriod is automatically generated by addition of different period types, e.g. Year(1) + Day(1) produces a CompoundPeriod result.

Instant

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

UTInstant{T}

The UTInstant represents a machine timeline based on UT time (1 day = one revolution of the earth). The T is a Period parameter that indicates the resolution or precision of the instant.

TimeType

TimeType types wrap Instant machine instances to provide human representations of the machine instant. Time, DateTime and Date are subtypes of TimeType.

DateTime

DateTime wraps a UTInstant{Millisecond} and interprets it according to the proleptic Gregorian calendar.

Date

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

Time

Time wraps a Nanosecond 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 the TimeZones.jl package

UTC

UTC, or Coordinated Universal Time, is the TimeZone 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 a DateTime type by parts. Arguments must be convertible to Int64.

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

Construct a DateTime type by Period type parts. Arguments may be in any order. DateTime parts not provided will default to the value of Dates.default(period).

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

Create a DateTime through the adjuster API. The starting point will be constructed from the provided y, m, d... arguments, and will be adjusted until f::Function returns true. The step size in adjusting can be provided manually through the step keyword. limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (in the case that f::Function is never satisfied).

Examples

julia> DateTime(dt -> Dates.second(dt) == 40, 2010, 10, 20, 10; step = Dates.Second(1))
2010-10-20T10:00:40

julia> DateTime(dt -> Dates.hour(dt) == 20, 2010, 10, 20, 10; step = Dates.Hour(1), limit = 5)
ERROR: ArgumentError: Adjustment limit reached: 5 iterations
Stacktrace:
[...]

DateTime(dt::Date) -> DateTime

Convert a Date to a DateTime. The hour, minute, second, and millisecond parts of the new DateTime are assumed to be zero.

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

Construct a DateTime by parsing the dt date time string following the pattern given in the format string (see DateFormat for syntax).

Example

julia> DateTime("2020-01-01", "yyyy-mm-dd")
2020-01-01T00:00:00

julia> a = ("2020-01-01", "2020-01-02");

julia> [DateTime(d, dateformat"yyyy-mm-dd") for d ∈ a] # preferred
2-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 a TimeType object and applying the provided format. The following character codes can be used to construct the format string:

The number of sequential code characters indicate the width of the code. A format of yyyy-mm specifies that the code y should have a width of four while m 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 a format you can use any non-code characters as a separator. For example to generate the string "1996-01-15T00:00:00" you could use format: "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 "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 the format string:

Characters not listed above are normally treated as delimiters between date and time slots. For example a dt string of "1996-01-15T00:00:00.0" would have a format 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 a p specifier, any hour (either H or I) is interpreted as as a 12-hour clock, so the I code is mainly useful for output.

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

See DateTime and format for how to use a DateFormat object to parse and write Date strings respectively.

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

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

See DateFormat for details about format specifiers.

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

Construct a DateTime by parsing the dt date time string following the pattern given in the DateFormat object, or dateformat"yyyy-mm-ddTHH:MM:SS.s" if omitted.

Similar to DateTime(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted date time strings with a pre-created DateFormat object.

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

Construct a Date type by parts. Arguments must be convertible to Int64.

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

Construct a Date type by Period type parts. Arguments may be in any order. Date parts not provided will default to the value of Dates.default(period).

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

Create a Date through the adjuster API. The starting point will be constructed from the provided y, m, d arguments, and will be adjusted until f::Function returns true. The step size in adjusting can be provided manually through the step keyword. limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (given that f::Function is never satisfied).

Examples

julia> Date(date -> Dates.week(date) == 20, 2010, 01, 01)
2010-05-17

julia> Date(date -> Dates.year(date) == 2010, 2000, 01, 01)
2010-01-01

julia> Date(date -> Dates.month(date) == 10, 2000, 01, 01; limit = 5)
ERROR: ArgumentError: Adjustment limit reached: 5 iterations
Stacktrace:
[...]

Date(dt::DateTime) -> Date

Convert a DateTime to a Date. The hour, minute, second, and millisecond parts of the DateTime are truncated, so only the year, month and day parts are used in construction.

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

Construct a Date by parsing the d date string following the pattern given in the format string (see DateFormat for syntax).

Example

julia> Date("2020-01-01", "yyyy-mm-dd")
2020-01-01

julia> a = ("2020-01-01", "2020-01-02");

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

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

Construct a Date by parsing the d date string following the pattern given in the DateFormat object, or dateformat"yyyy-mm-dd" if omitted.

Similar to Date(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted date strings with a pre-created DateFormat object.

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

Construct a Time type by parts. Arguments must be convertible to Int64.

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

Construct a Time type by Period type parts. Arguments may be in any order. Time parts not provided will default to the value of Dates.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 a Time through the adjuster API. The starting point will be constructed from the provided h, mi, s, ms, us arguments, and will be adjusted until f::Function returns true. The step size in adjusting can be provided manually through the step keyword. limit provides a limit to the max number of iterations the adjustment API will pursue before throwing an error (in the case that f::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 be Millisecond(1) instead of Second(1).

Examples

julia> Dates.Time(t -> Dates.minute(t) == 30, 20)
20:30:00

julia> Dates.Time(t -> Dates.minute(t) == 0, 20)
20:00:00

julia> Dates.Time(t -> Dates.hour(t) == 10, 3; limit = 5)
ERROR: ArgumentError: Adjustment limit reached: 5 iterations
Stacktrace:
[...]

Time(dt::DateTime) -> Time

Convert a DateTime to a Time. The hour, minute, second, and millisecond parts of the DateTime are used to create the new Time. Microsecond and nanoseconds are zero by default.

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

Construct a Time by parsing the t time string following the pattern given in the format string (see DateFormat for syntax).

Example

julia> Time("12:34pm", "HH:MMp")
12:34:00

julia> a = ("12:34pm", "2:34am");

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

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

Construct a Time by parsing the t date time string following the pattern given in the DateFormat object, or dateformat"HH:MM:SS.s" if omitted.

Similar to Time(::AbstractString, ::AbstractString) but more efficient when repeatedly parsing similarly formatted time strings with a pre-created DateFormat object.

now() -> DateTime

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

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

Return a DateTime corresponding to the user's system time as UTC/GMT.

eps(::Type{DateTime}) -> Millisecond
eps(::Type{Date}) -> Day
eps(::Type{Time}) -> Nanosecond
eps(::TimeType) -> Period

Return the smallest unit value supported by the TimeType.

Examples

julia> eps(DateTime)
1 millisecond

julia> eps(Date)
1 day

julia> eps(Time)
1 nanosecond

year(dt::TimeType) -> Int64

The year of a Date or DateTime as an Int64.

month(dt::TimeType) -> Int64

The month of a Date or DateTime as an Int64.

week(dt::TimeType) -> Int64

Return the ISO week date of a Date or DateTime as an Int64. 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> Dates.week(Date(1989, 6, 22))
25

julia> Dates.week(Date(2005, 1, 1))
53

julia> Dates.week(Date(2004, 12, 31))
53

day(dt::TimeType) -> Int64

The day of month of a Date or DateTime as an Int64.

hour(dt::DateTime) -> Int64

The hour of day of a DateTime as an Int64.

hour(t::Time) -> Int64

The hour of a Time as an Int64.

minute(dt::DateTime) -> Int64

The minute of a DateTime as an Int64.

minute(t::Time) -> Int64

The minute of a Time as an Int64.

second(dt::DateTime) -> Int64

The second of a DateTime as an Int64.

second(t::Time) -> Int64

The second of a Time as an Int64.

millisecond(dt::DateTime) -> Int64

The millisecond of a DateTime as an Int64.

millisecond(t::Time) -> Int64

The millisecond of a Time as an Int64.

microsecond(t::Time) -> Int64

The microsecond of a Time as an Int64.

nanosecond(t::Time) -> Int64

The nanosecond of a Time as an Int64.

Year(v)

Construct a Year object with the given v value. Input must be losslessly convertible to an Int64.

Month(v)

Construct a Month object with the given v value. Input must be losslessly convertible to an Int64.

Week(v)

Construct a Week object with the given v value. Input must be losslessly convertible to an Int64.

Day(v)

Construct a Day object with the given v value. Input must be losslessly convertible to an Int64.

Hour(dt::DateTime) -> Hour

The hour part of a DateTime as a Hour.

Minute(dt::DateTime) -> Minute

The minute part of a DateTime as a Minute.

Second(dt::DateTime) -> Second

The second part of a DateTime as a Second.

Millisecond(dt::DateTime) -> Millisecond

The millisecond part of a DateTime as a Millisecond.

Microsecond(dt::Time) -> Microsecond

The microsecond part of a Time as a Microsecond.

Nanosecond(dt::Time) -> Nanosecond

The nanosecond part of a Time as a Nanosecond.

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

Simultaneously return the year and month parts of a Date or DateTime.

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

Simultaneously return the month and day parts of a Date or DateTime.

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

Simultaneously return the year, month and day parts of a Date or DateTime.

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

Return the full day name corresponding to the day of the week of the Date or DateTime in the given locale. Also accepts Integer.

Examples

julia> Dates.dayname(Date("2000-01-01"))
"Saturday"

julia> Dates.dayname(4)
"Thursday"

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

Return the abbreviated name corresponding to the day of the week of the Date or DateTime in the given locale. Also accepts Integer.

Examples

julia> Dates.dayabbr(Date("2000-01-01"))
"Sat"

julia> Dates.dayabbr(3)
"Wed"

dayofweek(dt::TimeType) -> Int64

Return the day of the week as an Int64 with 1 = Monday, 2 = Tuesday, etc..

Examples

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

dayofmonth(dt::TimeType) -> Int64

The day of month of a Date or DateTime as an Int64.

dayofweekofmonth(dt::TimeType) -> Int

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

Examples

julia> Dates.dayofweekofmonth(Date("2000-02-01"))
1

julia> Dates.dayofweekofmonth(Date("2000-02-08"))
2

julia> Dates.dayofweekofmonth(Date("2000-02-15"))
3

daysofweekinmonth(dt::TimeType) -> Int

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

Examples

julia> Dates.daysofweekinmonth(Date("2005-01-01"))
5

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

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

Return the full name of the month of the Date or DateTime or Integer in the given locale.

Examples

julia> Dates.monthname(Date("2005-01-04"))
"January"

julia> Dates.monthname(2)
"February"

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

Return the abbreviated month name of the Date or DateTime or Integer in the given locale.

Examples

julia> Dates.monthabbr(Date("2005-01-04"))
"Jan"

julia> monthabbr(2)
"Feb"

daysinmonth(dt::TimeType) -> Int

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

Examples

julia> Dates.daysinmonth(Date("2000-01"))
31

julia> Dates.daysinmonth(Date("2001-02"))
28

julia> Dates.daysinmonth(Date("2000-02"))
29

isleapyear(dt::TimeType) -> Bool

Return true if the year of dt is a leap year.

Examples

julia> Dates.isleapyear(Date("2004"))
true

julia> Dates.isleapyear(Date("2005"))
false

dayofyear(dt::TimeType) -> Int

Return the day of the year for dt with January 1st being day 1.

daysinyear(dt::TimeType) -> Int

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

Examples

julia> Dates.daysinyear(1999)
365

julia> Dates.daysinyear(2000)
366

quarterofyear(dt::TimeType) -> Int

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

dayofquarter(dt::TimeType) -> Int

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

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

Truncates the value of dt according to the provided Period type.

Examples

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

firstdayofweek(dt::TimeType) -> TimeType

Adjusts dt to the Monday of its week.

Examples

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

lastdayofweek(dt::TimeType) -> TimeType

Adjusts dt to the Sunday of its week.

Examples

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

firstdayofmonth(dt::TimeType) -> TimeType

Adjusts dt to the first day of its month.

Examples

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

lastdayofmonth(dt::TimeType) -> TimeType

Adjusts dt to the last day of its month.

Examples

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

firstdayofyear(dt::TimeType) -> TimeType

Adjusts dt to the first day of its year.

Examples

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

lastdayofyear(dt::TimeType) -> TimeType

Adjusts dt to the last day of its year.

Examples

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

firstdayofquarter(dt::TimeType) -> TimeType

Adjusts dt to the first day of its quarter.

Examples

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

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

lastdayofquarter(dt::TimeType) -> TimeType

Adjusts dt to the last day of its quarter.

Examples

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

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

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

Adjusts dt to the next day of week corresponding to dow with 1 = Monday, 2 = Tuesday, etc. Setting same=true allows the current dt to be considered as the next dow, allowing for no adjustment to occur.

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

Adjusts dt to the previous day of week corresponding to dow with 1 = Monday, 2 = Tuesday, etc. Setting same=true allows the current dt to be considered as the previous dow, allowing for no adjustment to occur.

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

Adjusts dt to the first dow of its month. Alternatively, of=Year will adjust to the first dow of the year.

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

Adjusts dt to the last dow of its month. Alternatively, of=Year will adjust to the last dow of the year.

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

Adjusts dt by iterating at most limit iterations by step increments until func returns true. func must take a single TimeType argument and return a Bool. same allows dt to be considered in satisfying func.

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

Adjusts dt by iterating at most limit iterations by step increments until func returns true. func must take a single TimeType argument and return a Bool. same allows dt to be considered in satisfying func.

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

Construct a Period type with the given v value. Input must be losslessly convertible to an Int64.

CompoundPeriod(periods) -> CompoundPeriod

Construct a CompoundPeriod from a Vector of Periods. All Periods of the same type will be added together.

Examples

julia> Dates.CompoundPeriod(Dates.Hour(12), Dates.Hour(13))
25 hours

julia> Dates.CompoundPeriod(Dates.Hour(-1), Dates.Minute(1))
-1 hour, 1 minute

julia> Dates.CompoundPeriod(Dates.Month(1), Dates.Week(-2))
1 month, -2 weeks

julia> Dates.CompoundPeriod(Dates.Minute(50000))
50000 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

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

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

Return the Vector of Periods that comprise the given CompoundPeriod.

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

Return the nearest Date or DateTime less than or equal to dt at resolution p.

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

julia> floor(Date(1985, 8, 16), Dates.Month)
1985-08-01

julia> floor(DateTime(2013, 2, 13, 0, 31, 20), Dates.Minute(15))
2013-02-13T00:30:00

julia> floor(DateTime(2016, 8, 6, 12, 0, 0), Dates.Day)
2016-08-06T00:00:00

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

Return the nearest Date or DateTime greater than or equal to dt at resolution p.

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

julia> ceil(Date(1985, 8, 16), Dates.Month)
1985-09-01

julia> ceil(DateTime(2013, 2, 13, 0, 31, 20), Dates.Minute(15))
2013-02-13T00:45:00

julia> ceil(DateTime(2016, 8, 6, 12, 0, 0), Dates.Day)
2016-08-07T00:00:00

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

Return the Date or DateTime nearest to dt at resolution p. 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 for round(dt, Dates.Hour(1)).

julia> round(Date(1985, 8, 16), Dates.Month)
1985-08-01

julia> round(DateTime(2013, 2, 13, 0, 31, 20), Dates.Minute(15))
2013-02-13T00:30:00

julia> round(DateTime(2016, 8, 6, 12, 0, 0), Dates.Day)
2016-08-07T00:00:00

Valid rounding modes for round(::TimeType, ::Period, ::RoundingMode) are RoundNearestTiesUp (default), RoundDown (floor), and RoundUp (ceil).

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

Round x down to the nearest multiple of precision. If x and precision are different subtypes of Period, the return value will have the same type as precision.

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

julia> floor(Dates.Day(16), Dates.Week)
2 weeks

julia> floor(Dates.Minute(44), Dates.Minute(15))
30 minutes

julia> floor(Dates.Hour(36), Dates.Day)
1 day

Rounding to a precision of Months or Years is not supported, as these Periods are of inconsistent length.

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

Round x up to the nearest multiple of precision. If x and precision are different subtypes of Period, the return value will have the same type as precision.

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

julia> ceil(Dates.Day(16), Dates.Week)
3 weeks

julia> ceil(Dates.Minute(44), Dates.Minute(15))
45 minutes

julia> ceil(Dates.Hour(36), Dates.Day)
2 days

Rounding to a precision of Months or Years is not supported, as these Periods are of inconsistent length.

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

Round x to the nearest multiple of precision. If x and precision are different subtypes of Period, the return value will have the same type as precision. 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 for round(x, Dates.Hour(1)).

julia> round(Dates.Day(16), Dates.Week)
2 weeks

julia> round(Dates.Minute(44), Dates.Minute(15))
45 minutes

julia> round(Dates.Hour(36), Dates.Day)
2 days

Valid rounding modes for round(::Period, ::T, ::RoundingMode) are RoundNearestTiesUp (default), RoundDown (floor), and RoundUp (ceil).

Rounding to a precision of Months or Years is not supported, as these Periods are of inconsistent length.

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

Simultaneously return the floor and ceil of a Date or DateTime at resolution p. More efficient than calling both floor and ceil individually.

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

Simultaneously return the floor and ceil of Period at resolution p. More efficient than calling both floor and ceil individually.

epochdays2date(days) -> Date

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

epochms2datetime(milliseconds) -> DateTime

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

date2epochdays(dt::Date) -> Int64

Take the given Date and return the number of days since the rounding epoch (0000-01-01T00:00:00) as an Int64.

datetime2epochms(dt::DateTime) -> Int64

Take the given DateTime and return the number of milliseconds since the rounding epoch (0000-01-01T00:00:00) as an Int64.

today() -> Date

Return the date portion of now().

unix2datetime(x) -> DateTime

Take the number of seconds since unix epoch 1970-01-01T00:00:00 and convert to the corresponding DateTime.

datetime2unix(dt::DateTime) -> Float64

Take the given DateTime and return the number of seconds since the unix epoch 1970-01-01T00:00:00 as a Float64.

julian2datetime(julian_days) -> DateTime

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

datetime2julian(dt::DateTime) -> Float64

Take the given DateTime and return the number of Julian calendar days since the julian epoch -4713-11-24T12:00:00 as a Float64.

rata2datetime(days) -> DateTime

Take the number of Rata Die days since epoch 0000-12-31T00:00:00 and return the corresponding DateTime.

datetime2rata(dt::TimeType) -> Int64

Return the number of Rata Die days since epoch from the given Date or DateTime.

Dates.ISODateTimeFormat

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

Example

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 for Dates.format of a Date.

Example

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 for Dates.format of a Time.

Example

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

Dates.RFC1123Format

Describes the RFC1123 formatting for a date and time.

Example

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