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Module Calendar


module Calendar: sig .. end
Calendar operations.

This module combines the implementations on Date and Time. So, a calendar is a 6-uple (year, month, day, hour, minute, second).

If you only need operations on dates, you should better use the module Date. But if you need to manage more precise date, use this module. The exact Julian period is now [January, 1st 4713 BC at midday GMT; January 22th, 3268 AC at midday GMT].

This module uses floating point arithmetics. Then, egality over calendars may be erroneous (as egality over float). You should better use the equal function defined in this module instead of (=).


Datatypes


type t
Type of a date refined with a time, so called a calendar.
type day = Date.day =
| Sun
| Mon
| Tue
| Wed
| Thu
| Fri
| Sat (*Days of the week.*) 
type month = Date.month =
| Jan
| Feb
| Mar
| Apr
| May
| Jun
| Jul
| Aug
| Sep
| Oct
| Nov
| Dec (*Months of the year.*) 
type year = Date.year
Year as an int
type field = [ `Day | `Hour | `Minute | `Month | `Second | `Week | `Year ]
The different fields of a calendar.

Constructors


val make : int -> int -> int -> int -> int -> int -> t
make year month day hour minute second makes the calendar "year-month-day; hour-minute-second".
val lmake : year:int ->
       ?month:int ->
       ?day:int -> ?hour:int -> ?minute:int -> ?second:int -> unit -> t
Labelled version of make. The default value of month and day (resp. of hour, minute and second) is 1 (resp. 0).
Since 1.05
val create : Date.t -> Time.t -> t
create d t creates a calendar from the given date and time.
val now : unit -> t
now () returns the current date and time (in the current time zone).
val from_jd : float -> t
Return the Julian day. More precise than Date.from_jd: the fractional part represents the time.
val from_mjd : float -> t
Return the Modified Julian day. It is Julian day - 2 400 000.5 (more precise than Date.from_mjd).

Conversions



Those functions have the same behaviour as those defined in Time.
val convert : t -> Time_Zone.t -> Time_Zone.t -> t
val to_gmt : t -> t
val from_gmt : t -> t

Getters



Those functions have the same behavious as those defined in Date.
val days_in_month : t -> int
val day_of_week : t -> day
val day_of_month : t -> int
val day_of_year : t -> int
val week : t -> int
val month : t -> month
val year : t -> int

to_jd and to_mjd are more precise than Date.to_jd and Date.to_mjd.
val to_jd : t -> float
val to_mjd : t -> float

Those functions have the same behavious as those defined in Time.
val hour : t -> int
val minute : t -> int
val second : t -> int

Boolean operations on calendars


val equal : t -> t -> bool
Equality function between two calendars. equal should be used instead of (=).

Those functions have the same behavious as those defined in Date.
val compare : t -> t -> int
val is_leap_day : t -> bool
val is_gregorian : t -> bool
val is_julian : t -> bool

Those functions have the same behavious as those defined in Time.
val is_pm : t -> bool
val is_am : t -> bool

Coercions


val to_unixtm : t -> Unix.tm
Convert a calendar into the unix.tm type. The field isdst is always false. More precise than Date.to_unixtm.
Since 1.01
val from_unixtm : Unix.tm -> t
Inverse of to_unixtm. Assumes the current time zone. So, we have the following invariant: hour (from_unixtm u) = u.Unix.tm_hour.
Since 1.01
val to_unixfloat : t -> float
Convert a calendar to a float such than to_unixfloat (make 1970 1 1 0 0 0) returns 0.0 at UTC. So such a float is convertible with those of the Unix module. More precise than Date.to_unixfloat.
Since 1.01
val from_unixfloat : float -> t
Inverse of to_unixfloat. Assumes the current time zone. So, we have the following invariant: hour (from_unixfloat u) = (Unix.gmtime u).Unix.tm_hour.
Since 1.01
val from_date : Date.t -> t
Convert a date to a calendar. The time is midnight in the current time zone.
val to_date : t -> Date.t
Convert a calendar to a date. Time part of the calendar is ignored.
val to_time : t -> Time.t
Convert a calendar to a time. Date part of the calendar is ignored.
Since 1.03

Period


module Period: sig .. end

Arithmetic operations on calendars and periods



Those functions have the same behavious as those defined in Date.
val add : t -> Period.t -> t
val sub : t -> t -> Period.t
val rem : t -> Period.t -> t
val next : t -> field -> t
val prev : t -> field -> t