module type S =sig
..end
Common operations for all date representations.
typefield =
Period.date_field
The different fields of a date.
type -[< field ]
date
Type of a date, without specifying any precision level.
typet =
field date
Type of a date.
type
day =
| |
Sun |
| |
Mon |
| |
Tue |
| |
Wed |
| |
Thu |
| |
Fri |
| |
Sat |
Days of the week.
type
month =
| |
Jan |
| |
Feb |
| |
Mar |
| |
Apr |
| |
May |
| |
Jun |
| |
Jul |
| |
Aug |
| |
Sep |
| |
Oct |
| |
Nov |
| |
Dec |
Months of the year.
typeyear =
int
Year as an int
.
exception Out_of_bounds
Raised when a date is outside the Julian period.
exception Undefined
Raised when a date belongs to
[October 5th, 1582; October 14th, 1582]
.
val make : year -> int -> int -> t
make year month day
makes the date year-month-day. A BC year y
corresponds to the year -(y+1)
.
Out_of_bounds
when a date is outside the Julian period.Undefined
when a date belongs to [October 5th, 1582; October
14th, 1582]
.val lmake : year:year -> ?month:int -> ?day:int -> unit -> t
Labelled version of make
.
The default value of month
and day
is 1
.
Out_of_bounds
when a date is outside the Julian period.Undefined
when a date belongs to [October 5th, 1582; October
14th, 1582]
.val make_year : int -> [< `Year ] date
make_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 -> [< `Month | `Year ] date
make_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 -> t
Date of the current day (based on Time_Zone.current ()
).
val from_jd : int -> t
Make a date from its Julian day.
from_jd 0
returns the date 4713 BC-1-1.val from_mjd : int -> t
Make 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.
from_mjd 0
returns the date 1858-11-17.val from_day_of_year : year -> int -> t
Make a date from a year and its day of the year.
from_day_of_year 2008 39
returns the date 2008-2-8.val days_in_month : [< field > `Month `Year ] date -> int
Number of days in the month of a date.
days_in_month (make 2003 6 26)
returns 30
.val day_of_week : t -> day
Day of the week.
day_of_week (make 2003 6 26)
returns Thu
.val day_of_month : t -> int
Day of the month.
day_of_month (make 2003 6 26)
returns 26
.val day_of_year : t -> int
Day of the year.
day_of_year (make 2003 12 28)
returns 362
.day_of_year (make 2003 1 5)
returns 5
val week : t -> int
Week.
week (make 2003 12 29)
returns 1
.week (make 2003 12 28)
returns 52
.week (make 2000 1 2)
returns 52
.week (make 2000 1 3)
returns 1
.val month : [< field > `Month ] date -> month
Month.
month (make 2003 6 26)
returns Jun
.val year : [< field > `Year ] date -> year
Year.
year (make 2003 6 26)
returns 2003
.val to_jd : t -> int
Julian day.
to_jd (make (-4712) 1 1)
returns 0.val to_mjd : t -> int
Modified Julian day (i.e. Julian day - 2 400 001). The Modified Julian day is more manageable than the Julian day.
to_mjd (make 1858 11 17)
returns 0.val equal : [< field ] date ->
[< field ] date -> bool
Equality function between two dates.
val compare : [< field ] date ->
[< field ] date -> int
Comparison function between two dates.
val hash : [< field ] date -> int
Hash function for dates.
val is_valid_date : year -> int -> int -> bool
Check if a date is valid, that is the date has not been coerced to look like a real date.
is_valid_date 2008 2 30
returns false
is_valid_date 2008 2 8
returns true
val is_leap_day : t -> bool
Return true
if a date is a leap day
(i.e. February, 24th of a leap year); false
otherwise.
val is_gregorian : t -> bool
Return true
if a date belongs to the Gregorian calendar;
false
otherwise.
val is_julian : t -> bool
Return true
iff a date belongs to the Julian calendar;
false
otherwise.
val to_unixtm : t -> Unix.tm
Convert 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 -> t
Inverse of to_unixtm
. Assume the current time zone.
val to_unixfloat : t -> float
Convert 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 -> t
Inverse of to_unixfloat
. Ignore the fractional part of the argument.
Assume the current time zone.
val to_business : t -> year * int * day
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.
to_business (make 2003 12 29)
returns 2004, 1, Mon
.to_business (make 2003 12 28)
returns 2003, 52, Sun
to_business (make 2000 1 2)
returns 1999, 52, Sun
to_business (make 2000 1 3)
returns 2000, 1, Mon
val from_business : year -> int -> day -> t
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.
Invalid_argument
if the date is bad.val int_of_day : day -> int
Convert a day to an integer respecting ISO-8601. So, Monday is 1, Tuesday is 2, ..., and sunday is 7.
val day_of_int : int -> day
Inverse of int_of_day
.
Invalid_argument
if the argument does not belong to 1; 7
.val int_of_month : month -> int
Convert a month to an integer respecting ISO-8601. So, January is 1, February is 2 and so on.
val month_of_int : int -> month
Inverse of int_of_month
.
Invalid_argument
if the argument does not belong to 1; 12
.module Period:sig
..end
A period is the number of days between two dates.
val add : ([< field ] as 'a) date ->
'a Period.period -> 'a date
add d p
returns d + p
.
Out_of_bounds
when the resulting date is outside the Julian
period.Undefined
when the resulting date belongs to [October 5th,
1582; October 14th, 1582]
.add (make 2003 12 31) (Period.month 2)
returns the date
2004-3-2 (following the coercion rule describes in the introduction).add (make 2003 12 31) (Period.month 1)
returns the date
2004-1-31val sub : ([< field ] as 'a) date ->
'a date ->
[< field > `Day `Week ] Period.period
sub d1 d2
returns the period between d1
and d2
.
val precise_sub : ([< field ] as 'a) date ->
'a date -> Period.t
precise_sub d1 d2
returns the period between d1
and d2
.
It is equivalent to sub
, but:
val rem : ([< field ] as 'a) date ->
'a Period.period -> 'a date
rem d p
is equivalent to add d (Period.opp p)
.
Out_of_bounds
when the resulting date is outside the Julian
period.Undefined
when the resulting date belongs to [October 5th,
1582; October 14th, 1582]
.val next : ([< field ] as 'a) date -> 'a -> 'a date
next d f
returns the date corresponding to the next specified field.
Out_of_bounds
when the resulting date is outside the Julian
period.Undefined
when the resulting date belongs to [October 5th,
1582; October 14th, 1582]
.next (make 2003 12 31) `Month
returns the date 2004-1-31
(i.e. one month later).val prev : ([< field ] as 'a) date -> 'a -> 'a date
prev d f
returns the date corresponding to the previous specified
field.
Out_of_bounds
when the resulting date is outside the Julian
period.Undefined
when the resulting date belongs to [October 5th,
1582; October 14th, 1582]
.prev (make 2003 12 31) `Year
returns the date 2002-12-31
(i.e. one year ago).val is_leap_year : year -> bool
Return true
if a year is a leap year; false
otherwise.
val same_calendar : year -> year -> bool
Return true
if two years have the same calendar; false
otherwise.
val days_in_year : ?month:month -> year -> int
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 -> int
Number of weeks in a year.
val week_first_last : int -> year -> t * t
Return the first and last days of a week in a year.
val nth_weekday_of_month : year -> month -> day -> int -> t
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 -> int
Century of a year.
century 2001
returns 21.century 2000
returns 20val millenium : year -> int
Millenium of a year.
millenium 2001
returns 3.millenium 2000
returns 2val solar_number : year -> int
Solar 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 -> int
Indiction.
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 -> int
Golden 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 -> int
Epact.
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.
val easter : year -> t
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.
year -> t
: Carnaval Monday. carnaval y
is easter y - 48
.
val mardi_gras : year -> t
Mardi Gras. mardi_gras y
is easter y - 47
.
val ash : year -> t
Ash Wednesday. ash y
is easter y - 46
.
val palm : year -> t
Palm Sunday. palm y
is easter y - 7
.
val easter_friday : year -> t
Easter Friday. easter_friday y
is easter y - 2
.
val easter_saturday : year -> t
Easter Saturday. easter_saturday y
is easter y - 1
.
val easter_monday : year -> t
Easter Monday. easter_monday y
is easter y + 1
.
val ascension : year -> t
Ascension. ascension y
is easter y + 39
.
val withsunday : year -> t
Withsunday. withsunday y
is easter y + 49
.
val withmonday : year -> t
Withmonday. withmonday y
is easter y + 50
.
val corpus_christi : year -> t
Feast of Corpus Christi. corpus_christi y
is easter + 60
.