Date implementation.
include Date_sig.Stype field = Period.date_fieldThe different fields of a date.
type -'a date constraint 'a = [< field ]Type of a date, without specifying any precision level.
make year month day makes the date year-month-day. A BC year y corresponds to the year -(y+1). @example years (5 BC) and (1 BC) respectively correspond to years (-4) and 0.
Labelled version of make. The default value of month and day is 1.
val make_year : int -> [< `Year ] datemake_year y makes a date only represented by its year y. The month and the day of such a date are not relevant.
val make_year_month : int -> int -> [< `Year | `Month ] datemake_year_month y m makes a date only represented by its year y and its month m. The day of such a date is not relevant.
val today : unit -> tDate of the current day (based on Time_Zone.current ()).
val from_jd : int -> tMake a date from its Julian day. @example from_jd 0 returns the date 4713 BC-1-1.
val from_mjd : int -> tMake a date from its modified Julian day (i.e. Julian day - 2 400 001). The Modified Julian day is more manageable than the Julian day. @example from_mjd 0 returns the date 1858-11-17.
Make a date from a year and its day of the year. @example from_day_of_year 2008 39 returns the date 2008-2-8.
val days_in_month : [> `Year | `Month ] date -> intNumber of days in the month of a date. @example days_in_month (make 2003 6 26) returns 30.
val day_of_month : t -> intDay of the month. @example day_of_month (make 2003 6 26) returns 26.
val day_of_year : t -> intDay of the year. @example day_of_year (make 2003 1 5) returns 5 @example day_of_year (make 2003 12 28) returns 362.
val week : t -> intWeek. @example week (make 2000 1 3) returns 1. @example week (make 2000 1 2) returns 52. @example week (make 2003 12 28) returns 52. @example week (make 2003 12 29) returns 1.
val to_jd : t -> intJulian day. @example to_jd (make (-4712) 1 1) returns 0.
val to_mjd : t -> intModified Julian day (i.e. Julian day - 2 400 001). The Modified Julian day is more manageable than the Julian day. @example to_mjd (make 1858 11 17) returns 0.
val hash : 'a date -> intHash function for dates.
val is_valid_date : year -> int -> int -> boolCheck if a date is valid, that is the date has not been coerced to look like a real date. @example is_valid_date 2008 2 8 returns true @example is_valid_date 2008 2 30 returns false
val is_leap_day : t -> boolReturn true if a date is a leap day (i.e. February, 24th of a leap year); false otherwise.
val is_gregorian : t -> boolReturn true if a date belongs to the Gregorian calendar; false otherwise.
val is_julian : t -> boolReturn true iff a date belongs to the Julian calendar; false otherwise.
val to_unixtm : t -> Unix.tmConvert a date into the Unix.tm type. The field is_isdst is always false. The fields Unix.tm_sec, Unix.tm_min and Unix.tm_hour are irrelevant.
val from_unixtm : Unix.tm -> tInverse of to_unixtm. Assume the current time zone.
val to_unixfloat : t -> floatConvert a date to a float such than to_unixfloat (make 1970 1 1) returns 0.0. So such a float is convertible with those of the Unix module. The fractional part of the result is always 0.
val from_unixfloat : float -> tInverse of to_unixfloat. Ignore the fractional part of the argument. Assume the current time zone.
Return the "business week" and the day in this week respecting ISO 8601. Notice that business weeks at the beginning and end of the year can sometimes have year numbers which don't match the real year. @example to_business (make 2000 1 3) returns 2000, 1, Mon @example to_business (make 2000 1 2) returns 1999, 52, Sun @example to_business (make 2003 12 28) returns 2003, 52, Sun @example to_business (make 2003 12 29) returns 2004, 1, Mon.
Inverse of to_business respecting ISO-8601. Notice that business weeks at the beginning and end of the year can sometimes have year numbers which don't match the real year.
val int_of_day : day -> intConvert a day to an integer respecting ISO-8601. So, Monday is 1, Tuesday is 2, ..., and sunday is 7.
val day_of_int : int -> dayInverse of int_of_day.
val int_of_month : month -> intConvert a month to an integer respecting ISO-8601. So, January is 1, February is 2 and so on.
val month_of_int : int -> monthInverse of int_of_month.
module Period : sig ... endA period is the number of days between two dates.
val add : 'a date -> 'a Period.period -> 'a dateadd d p returns d + p.
val sub : 'a date -> 'a date -> [> `Week | `Day ] Period.periodsub d1 d2 returns the period between d1 and d2.
precise_sub d1 d2 returns the period between d1 and d2. It is equivalent to sub, but:
val rem : 'a date -> 'a Period.period -> 'a daterem d p is equivalent to add d (Period.opp p).
next d f returns the date corresponding to the next specified field.
prev d f returns the date corresponding to the previous specified field.
val is_leap_year : year -> boolReturn true if a year is a leap year; false otherwise.
Return true if two years have the same calendar; false otherwise.
Number of days in a year.
days_in_year ~month y returns the number of days in the year y up to the end of the given month. Thus days_in_year ~month:Dec y is the same as days_in_year y.
val weeks_in_year : year -> intNumber of weeks in a year.
nth_weekday_of_month y m d n returns the n-th day d in the month m of the year y (for instance the 3rd Thursday of the month).
val century : year -> intCentury of a year. @example century 2000 returns 20 @example century 2001 returns 21.
val millenium : year -> intMillenium of a year. @example millenium 2000 returns 2 @example millenium 2001 returns 3.
val solar_number : year -> intSolar number.
In the Julian calendar there is a one-to-one relationship between the Solar number and the day on which a particular date falls.
val indiction : year -> intIndiction.
The Indiction was used in the middle ages to specify the position of a year in a 15 year taxation cycle. It was introduced by emperor Constantine the Great on 1 September 312 and ceased to be used in 1806.
The Indiction has no astronomical significance.
val golden_number : year -> intGolden number.
Considering that the relationship between the moon's phases and the days of the year repeats itself every 19 years, it is natural to associate a number between 1 and 19 with each year. This number is the so-called Golden number.
val epact : year -> intEpact.
The Epact is a measure of the age of the moon (i.e. the number of days that have passed since an "official" new moon) on a particular date.
Easter Sunday.
In the Christian world, Easter (and the days immediately preceding it) is the celebration of the death and resurrection of Jesus in (approximately) AD 30.
Carnaval Monday. carnaval y is easter y - 48.