View Source Calendar.ISO (Elixir v1.10.2)

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

Types

"Before the Current Era" or "Before the Common Era" (BCE), for those years less than 1.

The "Current Era" or the "Common Era" (CE) which starts in year 1.

Integer that represents the day of the week, where 1 is Monday and 7 is Sunday.

The calendar era.

Microseconds with stored precision.

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.

Parses a date string.

Parses a naive datetime string.

Parses a time string.

Parses a UTC datetime string.

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

@type bce() :: 0

"Before the Current Era" or "Before the Common Era" (BCE), for those years less than 1.

@type ce() :: 1

The "Current Era" or the "Common Era" (CE) which starts in year 1.

@type day() :: 1..31
@type day_of_week() :: 1..7

Integer that represents the day of the week, where 1 is Monday and 7 is Sunday.

@type day_of_year() :: 1..366
@type era() :: bce() | ce()

The calendar era.

The ISO calendar has two eras:

  • CE - which starts in year 1 and is defined as era 1.
  • BCE - for those years less than 1 and is defined as era 0.
@type hour() :: 0..23
@type microsecond() :: {0..999_999, 0..6}

Microseconds with stored precision.

The precision represents the number of digits that must be used when representing the microseconds to external format. If the precision is 0, it means microseconds must be skipped.

@type minute() :: 0..59
@type month() :: 1..12
@type quarter_of_year() :: 1..4
@type second() :: 0..59
@type year() :: -9999..9999
@type year_of_era() :: {1..10000, era()}

Link to this section Functions

Link to this function

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

View Source (since 1.4.0)
@spec 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 = "Etc/UTC"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 0, 0)
"2017-08-01 01:02:03.00000Z"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 3600, 0)
"2017-08-01 01:02:03.00000+01:00"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 3600, 3600)
"2017-08-01 01:02:03.00000+02:00"

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)
@spec day_of_era(year(), month(), day()) :: Calendar.day_of_era()

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)
@spec day_of_week(year(), month(), day()) :: day_of_week()

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)
@spec day_of_year(year(), month(), day()) :: day_of_year()

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)
@spec 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)
@spec 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)
@spec 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)
@spec 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)
@spec 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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parse_date(string)

View Source (since 1.10.0)

Parses a date string.

Examples

iex> Calendar.ISO.parse_date("2015-01-23")
{:ok, {2015, 1, 23}}
iex> Calendar.ISO.parse_date("-2015-01-23")
{:ok, {-2015, 1, 23}}
iex> Calendar.ISO.parse_date("2015:01:23")
{:error, :invalid_format}
iex> Calendar.ISO.parse_date("2015-01-32")
{:error, :invalid_date}
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parse_naive_datetime(string)

View Source (since 1.10.0)

Parses a naive datetime string.

Examples

iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07Z")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}

iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07.0")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 1}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07,0123456")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07.0123456")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123Z")
{:ok, {2015, 1, 23, 23, 50, 7, {123000, 3}}}

iex> Calendar.ISO.parse_naive_datetime("2015-01-23P23:50:07")
{:error, :invalid_format}
iex> Calendar.ISO.parse_naive_datetime("2015:01:23 23-50-07")
{:error, :invalid_format}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07A")
{:error, :invalid_format}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:61")
{:error, :invalid_time}
iex> Calendar.ISO.parse_naive_datetime("2015-01-32 23:50:07")
{:error, :invalid_date}

iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123+02:30")
{:ok, {2015, 1, 23, 23, 50, 7, {123000, 3}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123+00:00")
{:ok, {2015, 1, 23, 23, 50, 7, {123000, 3}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123-02:30")
{:ok, {2015, 1, 23, 23, 50, 7, {123000, 3}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123-00:00")
{:error, :invalid_format}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123-00:60")
{:error, :invalid_format}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.123-24:00")
{:error, :invalid_format}
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parse_time(string)

View Source (since 1.10.0)

Parses a time string.

Examples

iex> Calendar.ISO.parse_time("23:50:07")
{:ok, {23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_time("23:50:07Z")
{:ok, {23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_time("T23:50:07Z")
{:ok, {23, 50, 7, {0, 0}}}

iex> Calendar.ISO.parse_time("23:50:07,0123456")
{:ok, {23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_time("23:50:07.0123456")
{:ok, {23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_time("23:50:07.123Z")
{:ok, {23, 50, 7, {123000, 3}}}

iex> Calendar.ISO.parse_time("2015:01:23 23-50-07")
{:error, :invalid_format}
iex> Calendar.ISO.parse_time("23:50:07A")
{:error, :invalid_format}
iex> Calendar.ISO.parse_time("23:50:07.")
{:error, :invalid_format}
iex> Calendar.ISO.parse_time("23:50:61")
{:error, :invalid_time}
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parse_utc_datetime(string)

View Source (since 1.10.0)

Parses a UTC datetime string.

Examples

iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07Z")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}, 0}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07.123+02:30")
{:ok, {2015, 1, 23, 21, 20, 7, {123000, 3}}, 9000}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07,123+02:30")
{:ok, {2015, 1, 23, 21, 20, 7, {123000, 3}}, 9000}

iex> Calendar.ISO.parse_utc_datetime("-2015-01-23T23:50:07Z")
{:ok, {-2015, 1, 23, 23, 50, 7, {0, 0}}, 0}

iex> Calendar.ISO.parse_utc_datetime("-2015-01-23T23:50:07,123+02:30")
{:ok, {-2015, 1, 23, 21, 20, 7, {123000, 3}}, 9000}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23P23:50:07")
{:error, :invalid_format}
iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07")
{:error, :missing_offset}
iex> Calendar.ISO.parse_utc_datetime("2015-01-23 23:50:61")
{:error, :invalid_time}
iex> Calendar.ISO.parse_utc_datetime("2015-01-32 23:50:07")
{:error, :invalid_date}
iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07.123-00:00")
{:error, :invalid_format}
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quarter_of_year(year, month, day)

View Source (since 1.8.0)
@spec quarter_of_year(year(), month(), day()) :: quarter_of_year()

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)
@spec time_from_day_fraction(Calendar.day_fraction()) ::
  {hour(), minute(), second(), microsecond()}

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)
@spec 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)
@spec 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, microsecond)

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)
@spec year_of_era(year()) :: {1..10000, era()}

Calculates the year and era from the given year.

The ISO calendar has two eras: the "current era" (CE) which starts in year 1 and is defined as era 1. And "before the current era" (BCE) 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}