Elixir v1.9.4 Calendar.ISO View Source

A calendar implementation that follows to ISO 8601.

This calendar implements the proleptic Gregorian calendar and is therefore compatible with the calendar used in most countries today. The proleptic means the Gregorian rules for leap years are applied for all time, consequently the dates give different results before the year 1583 from when the Gregorian calendar was adopted.

Note that while ISO 8601 allows times and datetimes to specify 24:00:00 as the zero hour of the next day, this notation is not supported by Elixir.

Link to this section Summary

Functions

Converts the given date into a string.

Calculates the day and era from the given year, month, and day.

Calculates the day of the week from the given year, month, and day.

Calculates the day of the year from the given year, month, and day.

Returns how many days there are in the given year-month.

Returns if the given year is a leap year.

Returns how many months there are in the given year.

Converts the Calendar.iso_days/0 format to the datetime format specified by this calendar.

Calculates the quarter of the year from the given year, month, and day.

Converts a day fraction to this Calendar's representation of time.

Returns the normalized day fraction of the specified time.

Determines if the date given is valid according to the proleptic Gregorian calendar.

Determines if the date given is valid according to the proleptic Gregorian calendar.

Calculates the year and era from the given year.

Link to this section Types

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month()

View Source
month() :: 1..12
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year()

View Source
year() :: -9999..9999

Link to this section Functions

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date_to_string(year, month, day, format \\ :extended)

View Source (since 1.4.0)
date_to_string(year(), month(), day(), :basic | :extended) :: String.t()

Converts the given date into a string.

By default, returns dates formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.date_to_string(2015, 2, 28)
"2015-02-28"
iex> Calendar.ISO.date_to_string(2017, 8, 1)
"2017-08-01"
iex> Calendar.ISO.date_to_string(-99, 1, 31)
"-0099-01-31"

iex> Calendar.ISO.date_to_string(2015, 2, 28, :basic)
"20150228"
iex> Calendar.ISO.date_to_string(-99, 1, 31, :basic)
"-00990131"
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datetime_to_string(year, month, day, hour, minute, second, microsecond, time_zone, zone_abbr, utc_offset, std_offset, format \\ :extended)

View Source (since 1.4.0)

Converts the datetime (with time zone) into a string.

By default, returns datetimes formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> time_zone = "Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CET", 3600, 0)
"2017-08-01 01:02:03.00000+01:00 CET Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CDT", 3600, 3600)
"2017-08-01 01:02:03.00000+02:00 CDT Europe/Berlin"

iex> time_zone = "America/Los_Angeles"
iex> Calendar.ISO.datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 5}, time_zone, "PST", -28800, 0)
"2015-02-28 01:02:03.00000-08:00 PST America/Los_Angeles"
iex> Calendar.ISO.datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 5}, time_zone, "PDT", -28800, 3600)
"2015-02-28 01:02:03.00000-07:00 PDT America/Los_Angeles"

iex> time_zone = "Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CET", 3600, 0, :basic)
"20170801 010203.00000+0100 CET Europe/Berlin"
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day_of_era(year, month, day)

View Source (since 1.8.0)
day_of_era(year(), month(), day()) :: {day :: pos_integer(), era :: 0..1}

Calculates the day and era from the given year, month, and day.

Examples

iex> Calendar.ISO.day_of_era(0, 1, 1)
{366, 0}
iex> Calendar.ISO.day_of_era(1, 1, 1)
{1, 1}
iex> Calendar.ISO.day_of_era(0, 12, 31)
{1, 0}
iex> Calendar.ISO.day_of_era(0, 12, 30)
{2, 0}
iex> Calendar.ISO.day_of_era(-1, 12, 31)
{367, 0}
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day_of_week(year, month, day)

View Source (since 1.4.0)
day_of_week(year(), month(), day()) :: 1..7

Calculates the day of the week from the given year, month, and day.

It is an integer from 1 to 7, where 1 is Monday and 7 is Sunday.

Examples

iex> Calendar.ISO.day_of_week(2016, 10, 31)
1
iex> Calendar.ISO.day_of_week(2016, 11, 1)
2
iex> Calendar.ISO.day_of_week(2016, 11, 2)
3
iex> Calendar.ISO.day_of_week(2016, 11, 3)
4
iex> Calendar.ISO.day_of_week(2016, 11, 4)
5
iex> Calendar.ISO.day_of_week(2016, 11, 5)
6
iex> Calendar.ISO.day_of_week(2016, 11, 6)
7
iex> Calendar.ISO.day_of_week(-99, 1, 31)
4
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day_of_year(year, month, day)

View Source (since 1.8.0)
day_of_year(year(), month(), day()) :: 1..366

Calculates the day of the year from the given year, month, and day.

It is an integer from 1 to 366.

Examples

iex> Calendar.ISO.day_of_year(2016, 1, 31)
31
iex> Calendar.ISO.day_of_year(-99, 2, 1)
32
iex> Calendar.ISO.day_of_year(2018, 2, 28)
59
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day_rollover_relative_to_midnight_utc()

View Source (since 1.5.0)
day_rollover_relative_to_midnight_utc() :: {0, 1}

See Calendar.day_rollover_relative_to_midnight_utc/0 for documentation.

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days_in_month(year, month)

View Source (since 1.4.0)
days_in_month(year(), month()) :: 28..31

Returns how many days there are in the given year-month.

Examples

iex> Calendar.ISO.days_in_month(1900, 1)
31
iex> Calendar.ISO.days_in_month(1900, 2)
28
iex> Calendar.ISO.days_in_month(2000, 2)
29
iex> Calendar.ISO.days_in_month(2001, 2)
28
iex> Calendar.ISO.days_in_month(2004, 2)
29
iex> Calendar.ISO.days_in_month(2004, 4)
30
iex> Calendar.ISO.days_in_month(-1, 5)
31
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leap_year?(year)

View Source (since 1.3.0)
leap_year?(year()) :: boolean()

Returns if the given year is a leap year.

Examples

iex> Calendar.ISO.leap_year?(2000)
true
iex> Calendar.ISO.leap_year?(2001)
false
iex> Calendar.ISO.leap_year?(2004)
true
iex> Calendar.ISO.leap_year?(1900)
false
iex> Calendar.ISO.leap_year?(-4)
true
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months_in_year(year)

View Source (since 1.7.0)
months_in_year(year()) :: 12

Returns how many months there are in the given year.

Example

iex> Calendar.ISO.months_in_year(2004)
12
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naive_datetime_from_iso_days(arg)

View Source (since 1.5.0)

Converts the Calendar.iso_days/0 format to the datetime format specified by this calendar.

Examples

iex> Calendar.ISO.naive_datetime_from_iso_days({0, {0, 86400}})
{0, 1, 1, 0, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({730_485, {0, 86400}})
{2000, 1, 1, 0, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({730_485, {43200, 86400}})
{2000, 1, 1, 12, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({-365, {0, 86400000000}})
{-1, 1, 1, 0, 0, 0, {0, 6}}
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naive_datetime_to_iso_days(year, month, day, hour, minute, second, microsecond)

View Source (since 1.5.0)

Returns the Calendar.iso_days/0 format of the specified date.

Examples

iex> Calendar.ISO.naive_datetime_to_iso_days(0, 1, 1, 0, 0, 0, {0, 6})
{0, {0, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(2000, 1, 1, 12, 0, 0, {0, 6})
{730485, {43200000000, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(2000, 1, 1, 13, 0, 0, {0, 6})
{730485, {46800000000, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(-1, 1, 1, 0, 0, 0, {0, 6})
{-365, {0, 86400000000}}
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naive_datetime_to_string(year, month, day, hour, minute, second, microsecond, format \\ :extended)

View Source (since 1.4.0)
naive_datetime_to_string(
  year(),
  month(),
  day(),
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond(),
  :basic | :extended
) :: String.t()

Converts the datetime (without time zone) into a string.

By default, returns datetimes formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.naive_datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 6})
"2015-02-28 01:02:03.000004"
iex> Calendar.ISO.naive_datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5})
"2017-08-01 01:02:03.00000"

iex> Calendar.ISO.naive_datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 6}, :basic)
"20150228 010203.000004"
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quarter_of_year(year, month, day)

View Source (since 1.8.0)
quarter_of_year(year(), month(), day()) :: 1..4

Calculates the quarter of the year from the given year, month, and day.

It is an integer from 1 to 4.

Examples

iex> Calendar.ISO.quarter_of_year(2016, 1, 31)
1
iex> Calendar.ISO.quarter_of_year(2016, 4, 3)
2
iex> Calendar.ISO.quarter_of_year(-99, 9, 31)
3
iex> Calendar.ISO.quarter_of_year(2018, 12, 28)
4
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time_from_day_fraction(arg)

View Source (since 1.5.0)

Converts a day fraction to this Calendar's representation of time.

Examples

iex> Calendar.ISO.time_from_day_fraction({1, 2})
{12, 0, 0, {0, 6}}
iex> Calendar.ISO.time_from_day_fraction({13, 24})
{13, 0, 0, {0, 6}}
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time_to_day_fraction(hour, minute, second, arg)

View Source (since 1.5.0)

Returns the normalized day fraction of the specified time.

Examples

iex> Calendar.ISO.time_to_day_fraction(0, 0, 0, {0, 6})
{0, 86400000000}
iex> Calendar.ISO.time_to_day_fraction(12, 34, 56, {123, 6})
{45296000123, 86400000000}
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time_to_string(hour, minute, second, microsecond, format \\ :extended)

View Source (since 1.5.0)
time_to_string(
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond(),
  :basic | :extended
) :: String.t()

Converts the given time into a string.

By default, returns times formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6})
"02:02:02.000002"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 2})
"02:02:02.00"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 0})
"02:02:02"

iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6}, :basic)
"020202.000002"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6}, :extended)
"02:02:02.000002"
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valid_date?(year, month, day)

View Source (since 1.5.0)
valid_date?(year(), month(), day()) :: boolean()

Determines if the date given is valid according to the proleptic Gregorian calendar.

Examples

iex> Calendar.ISO.valid_date?(2015, 2, 28)
true
iex> Calendar.ISO.valid_date?(2015, 2, 30)
false
iex> Calendar.ISO.valid_date?(-1, 12, 31)
true
iex> Calendar.ISO.valid_date?(-1, 12, 32)
false
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valid_time?(hour, minute, second, arg)

View Source (since 1.5.0)

Determines if the date given is valid according to the proleptic Gregorian calendar.

Note that while ISO 8601 allows times to specify 24:00:00 as the zero hour of the next day, this notation is not supported by Elixir. Leap seconds are not supported as well by the built-in Calendar.ISO.

Examples

iex> Calendar.ISO.valid_time?(10, 50, 25, {3006, 6})
true
iex> Calendar.ISO.valid_time?(23, 59, 60, {0, 0})
false
iex> Calendar.ISO.valid_time?(24, 0, 0, {0, 0})
false
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year_of_era(year)

View Source (since 1.8.0)
year_of_era(year()) :: {year(), era :: 0..1}

Calculates the year and era from the given year.

The ISO calendar has two eras: the current era which starts in year 1 and is defined as era "1". And a second era for those years less than 1 defined as era "0".

Examples

iex> Calendar.ISO.year_of_era(1)
{1, 1}
iex> Calendar.ISO.year_of_era(2018)
{2018, 1}
iex> Calendar.ISO.year_of_era(0)
{1, 0}
iex> Calendar.ISO.year_of_era(-1)
{2, 0}