DOOMSDAY
Day of Week for Given Date

DOOMSDAY is a Python library which is given the year, month and day of a date, and uses John Conway's doomsday algorithm to determine the corresponding day of the week.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

DOOMSDAY is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

DATES, a dataset directory which contains lists of dates in various calendar systems.

Reference:

1. John Conway,
   Tomorrow is the Day After Doomsday,
   Eureka,
   Volume 36, October 1973, pages 28-31.

Source Code:

• doomsday_gregorian.py, weekday given any date in Gregorian calendar.
• i4_modp.py, returns the nonnegative remainder of I4 division.
• i4_wrap.py, forces an I4 to lie between given limits by wrapping.
• timestamp.py, prints the current YMDHMS date as a time stamp.
• weekday_to_name_common.py, returns the name of a Common weekday.
• weekday_values.py, returns the day of the week for various dates.
• year_is_leap_gregorian.py, returns TRUE if the Gregorian year was a leap year.

Examples and Tests:

• doomsday_test.py, calls all the tests.
• doomsday_test.sh, runs all the tests.
• doomsday_test.txt, the output file.

You can go up one level to the Python source codes.