Persian (Solar Hijri) Calendar

This library implements the Solar Hijri calendar that is used in Iran and Afghanistan.

From wikipedia:

The Solar Hijri calendar (Persian: گاه‌شماری هجری خورشیدی‎, romanized: gāh-shomāri-ye hejri-ye khorshidi; Pashto: لمريز لېږدیز کلیز‎), also called the Solar Hejri calendar or Shamsi Hijri calendar, and abbreviated as SH, is the official calendar of Iran and Afghanistan. It begins on the March equinox (Nowruz) as determined by astronomical calculation for the Iran Standard Time meridian (52.5°E, UTC+03:30) and has years of 365 or 366 days.

Its determination of the start of each year is astronomically accurate year-to-year as opposed to the more fixed Gregorian calendar or "Common Era calendar" which, averaged out, has the same year length, achieving the same accuracy (a more simply patterned calendar of 365 days for three consecutive years plus an extra day in the next year, save for exceptions to the latter in three out of every four centuries). The start of the year and its number of days remain fixed to one of the two equinoxes, the astronomically important days which have the same duration of day as night. It results in less variability of all celestial bodies when comparing a specific calendar date from one year to others.[2]

Each of the twelve months corresponds with a zodiac sign. The first six months have 31 days, the next five have 30 days, and the last month has 29 days in usual years but 30 days in leap years. The New Year's Day always falls on the March equinox.

Usage

ex_cldr_calendars_persian conforms to both the Calendar and Cldr.Calendar behaviours and therefore the functions in the Date, DateTime, NaiveDateTime, Time and Calendar functions are supported.

For Elixir versions up to and including 1.9, a date can be created by:

iex> {:ok, date} = Date.new(1354, 1, 1, Cldr.Calendar.Persian)
{:ok, ~D[1354-01-01 Cldr.Calendar.Persian]}

For Elixir version 1.10 and later Sigil_D supports user-defined calendars:

iex> ~D[1354-01-01 Cldr.Calendar.Persian]
~D[1354-01-01 Cldr.Calendar.Persian]

Localization

ex_cldr_calendars_persian depends on ex_cldr_calendars which supports calendar localization. For full date and time formatting see ex_cldr_dates_times.

Basic localization is executed by the Cldr.Calendar.localize/3. For example:

iex> Cldr.Calendar.localize(date, :month, locale: "en")
"Farvardin"

iex> Cldr.Calendar.localize(date, :month, locale: "fa")
"فروردین"

iex> Cldr.Calendar.localize(date, :day_of_week, locale: "fa")
"جمعه"

iex> Cldr.Calendar.localize(date, :day_of_week, locale: "en")
"Fri"

Relationship to other libraries

This library is part of the CLDR-based libraries for Elixir including:

• ex_cldr
• ex_cldr_numbers
• ex_cldr_dates_times
• ex_cldr_units
• ex_cldr_lists
• ex_cldr_messages
• ex_cldr_calendars
• ex_cldr_currencies

Installation

The package can be installed by adding cldr_calendars_persian to your list of dependencies in mix.exs:

def deps do
  [
    {:ex_cldr_calendars_persian, "~> 1.0"}
  ]
end

Documentation can be found at https://hexdocs.pm/ex_cldr_calendars_persian.