Doc/library/calendar.rst
!calendar --- General calendar-related functions.. module:: calendar :synopsis: Functions for working with calendars, including some emulation of the Unix cal program.
Source code: :source:Lib/calendar.py
This module allows you to output calendars like the Unix :program:cal program,
and provides additional useful functions related to the calendar. By default,
these calendars have Monday as the first day of the week, and Sunday as the last
(the European convention). Use :func:setfirstweekday to set the first day of
the week to Sunday (6) or to any other weekday. Parameters that specify dates
are given as integers. For related
functionality, see also the :mod:datetime and :mod:time modules.
The functions and classes defined in this module use an idealized calendar, the current Gregorian calendar extended indefinitely in both directions. This matches the definition of the "proleptic Gregorian" calendar in Dershowitz and Reingold's book "Calendrical Calculations", where it's the base calendar for all computations. Zero and negative years are interpreted as prescribed by the ISO 8601 standard. Year 0 is 1 BC, year -1 is 2 BC, and so on.
.. class:: Calendar(firstweekday=0)
Creates a :class:Calendar object. firstweekday is an integer specifying the
first day of the week. :const:MONDAY is 0 (the default), :const:SUNDAY is 6.
A :class:Calendar object provides several methods that can be used for
preparing the calendar data for formatting. This class doesn't do any formatting
itself. This is the job of subclasses.
:class:Calendar instances have the following methods and attributes:
.. attribute:: firstweekday
The first weekday as an integer (0--6).
This property can also be set and read using
:meth:`~Calendar.setfirstweekday` and
:meth:`~Calendar.getfirstweekday` respectively.
.. method:: getfirstweekday()
Return an :class:`int` for the current first weekday (0--6).
Identical to reading the :attr:`~Calendar.firstweekday` property.
.. method:: setfirstweekday(firstweekday)
Set the first weekday to *firstweekday*, passed as an :class:`int` (0--6)
Identical to setting the :attr:`~Calendar.firstweekday` property.
.. method:: iterweekdays()
Return an iterator for the week day numbers that will be used for one
week. The first value from the iterator will be the same as the value of
the :attr:`~Calendar.firstweekday` property.
.. method:: itermonthdates(year, month)
Return an iterator for the month *month* (1--12) in the year *year*. This
iterator will return all days (as :class:`datetime.date` objects) for the
month and all days before the start of the month or after the end of the
month that are required to get a complete week.
.. method:: itermonthdays(year, month)
Return an iterator for the month *month* in the year *year* similar to
:meth:`itermonthdates`, but not restricted by the :class:`datetime.date`
range. Days returned will simply be day of the month numbers. For the
days outside of the specified month, the day number is ``0``.
.. method:: itermonthdays2(year, month)
Return an iterator for the month *month* in the year *year* similar to
:meth:`itermonthdates`, but not restricted by the :class:`datetime.date`
range. Days returned will be tuples consisting of a day of the month
number and a week day number.
.. method:: itermonthdays3(year, month)
Return an iterator for the month *month* in the year *year* similar to
:meth:`itermonthdates`, but not restricted by the :class:`datetime.date`
range. Days returned will be tuples consisting of a year, a month and a day
of the month numbers.
.. versionadded:: 3.7
.. method:: itermonthdays4(year, month)
Return an iterator for the month *month* in the year *year* similar to
:meth:`itermonthdates`, but not restricted by the :class:`datetime.date`
range. Days returned will be tuples consisting of a year, a month, a day
of the month, and a day of the week numbers.
.. versionadded:: 3.7
.. method:: monthdatescalendar(year, month)
Return a list of the weeks in the month *month* of the *year* as full
weeks. Weeks are lists of seven :class:`datetime.date` objects.
.. method:: monthdays2calendar(year, month)
Return a list of the weeks in the month *month* of the *year* as full
weeks. Weeks are lists of seven tuples of day numbers and weekday
numbers.
.. method:: monthdayscalendar(year, month)
Return a list of the weeks in the month *month* of the *year* as full
weeks. Weeks are lists of seven day numbers.
.. method:: yeardatescalendar(year, width=3)
Return the data for the specified year ready for formatting. The return
value is a list of month rows. Each month row contains up to *width*
months (defaulting to 3). Each month contains between 4 and 6 weeks and
each week contains 1--7 days. Days are :class:`datetime.date` objects.
.. method:: yeardays2calendar(year, width=3)
Return the data for the specified year ready for formatting (similar to
:meth:`yeardatescalendar`). Entries in the week lists are tuples of day
numbers and weekday numbers. Day numbers outside this month are zero.
.. method:: yeardayscalendar(year, width=3)
Return the data for the specified year ready for formatting (similar to
:meth:`yeardatescalendar`). Entries in the week lists are day numbers. Day
numbers outside this month are zero.
.. class:: TextCalendar(firstweekday=0)
This class can be used to generate plain text calendars.
:class:TextCalendar instances have the following methods:
.. method:: prweek(theweek, width)
Print a week's calendar as returned by :meth:`formatweek` and without a
final newline.
.. method:: formatday(theday, weekday, width)
Return a string representing a single day formatted with the given *width*.
If *theday* is ``0``, return a string of spaces of
the specified width, representing an empty day. The *weekday* parameter
is unused.
.. method:: formatweek(theweek, w=0)
Return a single week in a string with no newline. If *w* is provided, it
specifies the width of the date columns, which are centered. Depends
on the first weekday as specified in the constructor or set by the
:meth:`setfirstweekday` method.
.. method:: formatweekday(weekday, width)
Return a string representing the name of a single weekday formatted to
the specified *width*. The *weekday* parameter is an integer representing
the day of the week, where ``0`` is Monday and ``6`` is Sunday.
.. method:: formatweekheader(width)
Return a string containing the header row of weekday names, formatted
with the given *width* for each column. The names depend on the locale
settings and are padded to the specified width.
.. method:: formatmonth(theyear, themonth, w=0, l=0)
Return a month's calendar in a multi-line string. If *w* is provided, it
specifies the width of the date columns, which are centered. If *l* is
given, it specifies the number of lines that each week will use. Depends
on the first weekday as specified in the constructor or set by the
:meth:`setfirstweekday` method.
.. method:: formatmonthname(theyear, themonth, width=0, withyear=True)
Return a string representing the month's name centered within the
specified *width*. If *withyear* is ``True``, include the year in the
output. The *theyear* and *themonth* parameters specify the year
and month for the name to be formatted respectively.
.. method:: prmonth(theyear, themonth, w=0, l=0)
Print a month's calendar as returned by :meth:`formatmonth`.
.. method:: formatyear(theyear, w=2, l=1, c=6, m=3)
Return a *m*-column calendar for an entire year as a multi-line string.
Optional parameters *w*, *l*, and *c* are for date column width, lines per
week, and number of spaces between month columns, respectively. Depends on
the first weekday as specified in the constructor or set by the
:meth:`setfirstweekday` method. The earliest year for which a calendar
can be generated is platform-dependent.
.. method:: pryear(theyear, w=2, l=1, c=6, m=3)
Print the calendar for an entire year as returned by :meth:`formatyear`.
.. class:: HTMLCalendar(firstweekday=0)
This class can be used to generate HTML calendars.
:class:!HTMLCalendar instances have the following methods:
.. method:: formatmonth(theyear, themonth, withyear=True)
Return a month's calendar as an HTML table. If *withyear* is true the year
will be included in the header, otherwise just the month name will be
used.
.. method:: formatyear(theyear, width=3)
Return a year's calendar as an HTML table. *width* (defaulting to 3)
specifies the number of months per row.
.. method:: formatyearpage(theyear, width=3, css='calendar.css', encoding=None)
Return a year's calendar as a complete HTML page. *width* (defaulting to
3) specifies the number of months per row. *css* is the name for the
cascading style sheet to be used. :const:`None` can be passed if no style
sheet should be used. *encoding* specifies the encoding to be used for the
output (defaulting to ``'utf-8'``).
.. method:: formatmonthname(theyear, themonth, withyear=True)
Return a month name as an HTML table row. If *withyear* is true the year
will be included in the row, otherwise just the month name will be
used.
:class:!HTMLCalendar has the following attributes you can override to
customize the CSS classes used by the calendar:
.. attribute:: cssclasses
A list of CSS classes used for each weekday. The default class list is::
cssclasses = ["mon", "tue", "wed", "thu", "fri", "sat", "sun"]
more styles can be added for each day::
cssclasses = ["mon text-bold", "tue", "wed", "thu", "fri", "sat", "sun red"]
Note that the length of this list must be seven items.
.. attribute:: cssclass_noday
The CSS class for a weekday occurring in the previous or coming month.
.. versionadded:: 3.7
.. attribute:: cssclasses_weekday_head
A list of CSS classes used for weekday names in the header row.
The default is the same as :attr:`cssclasses`.
.. versionadded:: 3.7
.. attribute:: cssclass_month_head
The month's head CSS class (used by :meth:`formatmonthname`).
The default value is ``"month"``.
.. versionadded:: 3.7
.. attribute:: cssclass_month
The CSS class for the whole month's table (used by :meth:`formatmonth`).
The default value is ``"month"``.
.. versionadded:: 3.7
.. attribute:: cssclass_year
The CSS class for the whole year's table of tables (used by
:meth:`formatyear`). The default value is ``"year"``.
.. versionadded:: 3.7
.. attribute:: cssclass_year_head
The CSS class for the table head for the whole year (used by
:meth:`formatyear`). The default value is ``"year"``.
.. versionadded:: 3.7
Note that although the naming for the above described class attributes is
singular (e.g. cssclass_month cssclass_noday), one can replace the
single CSS class with a space separated list of CSS classes, for example::
"text-bold text-red"
Here is an example how :class:!HTMLCalendar can be customized::
class CustomHTMLCal(calendar.HTMLCalendar):
cssclasses = [style + " text-nowrap" for style in
calendar.HTMLCalendar.cssclasses]
cssclass_month_head = "text-center month-head"
cssclass_month = "text-center month"
cssclass_year = "text-italic lead"
.. class:: LocaleTextCalendar(firstweekday=0, locale=None)
This subclass of :class:TextCalendar can be passed a locale name in the
constructor and will return month and weekday names in the specified locale.
.. class:: LocaleHTMLCalendar(firstweekday=0, locale=None)
This subclass of :class:HTMLCalendar can be passed a locale name in the
constructor and will return month and weekday names in the specified
locale.
.. note::
The constructor, :meth:!formatweekday and :meth:!formatmonthname methods
of these two classes temporarily change the LC_TIME locale to the given
locale. Because the current locale is a process-wide setting, they are
not thread-safe.
For simple text calendars this module provides the following functions.
.. function:: setfirstweekday(weekday)
Sets the weekday (0 is Monday, 6 is Sunday) to start each week. The
values :const:MONDAY, :const:TUESDAY, :const:WEDNESDAY, :const:THURSDAY,
:const:FRIDAY, :const:SATURDAY, and :const:SUNDAY are provided for
convenience. For example, to set the first weekday to Sunday::
import calendar
calendar.setfirstweekday(calendar.SUNDAY)
.. function:: firstweekday()
Returns the current setting for the weekday to start each week.
.. function:: isleap(year)
Returns :const:True if year is a leap year, otherwise :const:False.
.. function:: leapdays(y1, y2)
Returns the number of leap years in the range from y1 to y2 (exclusive), where y1 and y2 are years.
This function works for ranges spanning a century change.
.. function:: weekday(year, month, day)
Returns the day of the week (0 is Monday) for year (1970--...),
month (1--12), day (1--31).
.. function:: weekheader(n)
Return a header containing abbreviated weekday names. n specifies the width in characters for one weekday.
.. function:: monthrange(year, month)
Returns weekday of first day of the month and number of days in month, for the specified year and month.
.. function:: monthcalendar(year, month)
Returns a matrix representing a month's calendar. Each row represents a week;
days outside of the month are represented by zeros. Each week begins with Monday
unless set by :func:setfirstweekday.
.. function:: prmonth(theyear, themonth, w=0, l=0)
Prints a month's calendar as returned by :func:month.
.. function:: month(theyear, themonth, w=0, l=0)
Returns a month's calendar in a multi-line string using the :meth:~TextCalendar.formatmonth
of the :class:TextCalendar class.
.. function:: prcal(year, w=0, l=0, c=6, m=3)
Prints the calendar for an entire year as returned by :func:calendar.
.. function:: calendar(year, w=2, l=1, c=6, m=3)
Returns a 3-column calendar for an entire year as a multi-line string using
the :meth:~TextCalendar.formatyear of the :class:TextCalendar class.
.. function:: timegm(tuple)
An unrelated but handy function that takes a time tuple such as returned by
the :func:~time.gmtime function in the :mod:time module, and returns the
corresponding Unix timestamp value, assuming an epoch of 1970, and the POSIX
encoding. In fact, :func:time.gmtime and :func:timegm are each others'
inverse.
The :mod:!calendar module exports the following data attributes:
.. data:: day_name
A sequence that represents the days of the week in the current locale, where Monday is day number 0.
>>> import calendar
>>> list(calendar.day_name)
['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']
.. data:: day_abbr
A sequence that represents the abbreviated days of the week in the current locale, where Mon is day number 0.
>>> import calendar
>>> list(calendar.day_abbr)
['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
.. data:: MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY
Aliases for the days of the week,
where MONDAY is 0 and SUNDAY is 6.
.. versionadded:: 3.12
.. class:: Day
Enumeration defining days of the week as integer constants.
The members of this enumeration are exported to the module scope as
:data:MONDAY through :data:SUNDAY.
.. versionadded:: 3.12
.. data:: month_name
A sequence that represents the months of the year in the current locale. This
follows normal convention of January being month number 1, so it has a length of
13 and month_name[0] is the empty string.
>>> import calendar
>>> list(calendar.month_name)
['', 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December']
.. caution::
In locales with alternative month names forms, the :data:`!month_name` sequence
may not be suitable when a month name stands by itself and not as part of a date.
For instance, in Greek and in many Slavic and Baltic languages, :data:`!month_name`
will produce the month in genitive case. Use :data:`standalone_month_name` for a form
suitable for standalone use.
.. data:: month_abbr
A sequence that represents the abbreviated months of the year in the current
locale. This follows normal convention of January being month number 1, so it
has a length of 13 and month_abbr[0] is the empty string.
>>> import calendar
>>> list(calendar.month_abbr)
['', 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
.. caution::
In locales with alternative month names forms, the :data:`!month_abbr` sequence
may not be suitable when a month name stands by itself and not as part of a date.
Use :data:`standalone_month_abbr` for a form suitable for standalone use.
.. data:: standalone_month_name
A sequence that represents the months of the year in the current locale
in the standalone form if the locale provides one. Else it is equivalent
to :data:month_name.
.. versionadded:: 3.15
.. data:: standalone_month_abbr
A sequence that represents the abbreviated months of the year in the current
locale in the standalone form if the locale provides one. Else it is
equivalent to :data:month_abbr.
.. versionadded:: 3.15
.. data:: JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER NOVEMBER DECEMBER
Aliases for the months of the year,
where JANUARY is 1 and DECEMBER is 12.
.. versionadded:: 3.12
.. class:: Month
Enumeration defining months of the year as integer constants.
The members of this enumeration are exported to the module scope as
:data:JANUARY through :data:DECEMBER.
.. versionadded:: 3.12
The :mod:!calendar module defines the following exceptions:
.. exception:: IllegalMonthError(month)
A subclass of :exc:ValueError,
raised when the given month number is outside of the range 1-12 (inclusive).
.. attribute:: month
The invalid month number.
.. exception:: IllegalWeekdayError(weekday)
A subclass of :exc:ValueError,
raised when the given weekday number is outside of the range 0-6 (inclusive).
.. attribute:: weekday
The invalid weekday number.
.. seealso::
Module :mod:datetime
Object-oriented interface to dates and times with similar functionality to the
:mod:time module.
Module :mod:time
Low-level time related functions.
.. _calendar-cli:
.. versionadded:: 2.5
The :mod:!calendar module can be executed as a script from the command line
to interactively print a calendar.
.. code-block:: shell
python -m calendar [-h] [-L LOCALE] [-e ENCODING] [-t {text,html}] [-w WIDTH] [-l LINES] [-s SPACING] [-m MONTHS] [-c CSS] [-f FIRST_WEEKDAY] [year] [month]
For example, to print a calendar for the year 2000:
.. code-block:: console
$ python -m calendar 2000 2000
January February March
Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su 1 2 1 2 3 4 5 6 1 2 3 4 5 3 4 5 6 7 8 9 7 8 9 10 11 12 13 6 7 8 9 10 11 12 10 11 12 13 14 15 16 14 15 16 17 18 19 20 13 14 15 16 17 18 19 17 18 19 20 21 22 23 21 22 23 24 25 26 27 20 21 22 23 24 25 26 24 25 26 27 28 29 30 28 29 27 28 29 30 31 31
April May June
Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su 1 2 1 2 3 4 5 6 7 1 2 3 4 3 4 5 6 7 8 9 8 9 10 11 12 13 14 5 6 7 8 9 10 11 10 11 12 13 14 15 16 15 16 17 18 19 20 21 12 13 14 15 16 17 18 17 18 19 20 21 22 23 22 23 24 25 26 27 28 19 20 21 22 23 24 25 24 25 26 27 28 29 30 29 30 31 26 27 28 29 30
July August September
Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su 1 2 1 2 3 4 5 6 1 2 3 3 4 5 6 7 8 9 7 8 9 10 11 12 13 4 5 6 7 8 9 10 10 11 12 13 14 15 16 14 15 16 17 18 19 20 11 12 13 14 15 16 17 17 18 19 20 21 22 23 21 22 23 24 25 26 27 18 19 20 21 22 23 24 24 25 26 27 28 29 30 28 29 30 31 25 26 27 28 29 30 31
October November December
Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su 1 1 2 3 4 5 1 2 3 2 3 4 5 6 7 8 6 7 8 9 10 11 12 4 5 6 7 8 9 10 9 10 11 12 13 14 15 13 14 15 16 17 18 19 11 12 13 14 15 16 17 16 17 18 19 20 21 22 20 21 22 23 24 25 26 18 19 20 21 22 23 24 23 24 25 26 27 28 29 27 28 29 30 25 26 27 28 29 30 31 30 31
The following options are accepted:
.. program:: calendar
.. option:: --help, -h
Show the help message and exit.
.. option:: --locale LOCALE, -L LOCALE
The locale to use for month and weekday names. Defaults to English.
.. option:: --encoding ENCODING, -e ENCODING
The encoding to use for output.
:option:--encoding is required if :option:--locale is set.
.. option:: --type {text,html}, -t {text,html}
Print the calendar to the terminal as text, or as an HTML document.
.. option:: --first-weekday FIRST_WEEKDAY, -f FIRST_WEEKDAY
The weekday to start each week. Must be a number between 0 (Monday) and 6 (Sunday). Defaults to 0.
.. versionadded:: 3.13
.. option:: year
The year to print the calendar for. Defaults to the current year.
.. option:: month
The month of the specified :option:year to print the calendar for.
Must be a number between 1 and 12.
Defaults to printing a calendar for the full year.
Text-mode options:
.. option:: --width WIDTH, -w WIDTH
The width of the date column in terminal columns. The date is printed centred in the column. Any value lower than 2 is ignored. Defaults to 2.
.. option:: --lines LINES, -l LINES
The number of lines for each week in terminal rows. The date is printed top-aligned. Any value lower than 1 is ignored. Defaults to 1.
.. option:: --spacing SPACING, -s SPACING
The space between months in columns. Any value lower than 2 is ignored. Defaults to 6.
.. option:: --months MONTHS, -m MONTHS
The number of months printed per row. Defaults to 3.
.. versionchanged:: 3.14
By default, today's date is highlighted in color and can be
:ref:controlled using environment variables <using-on-controlling-color>.
HTML-mode options:
.. option:: --css CSS, -c CSS
The path of a CSS stylesheet to use for the calendar.
This must either be relative to the generated HTML,
or an absolute HTTP or file:/// URL.