weekday

weekday, a C code which determines the day of the week corresponding to a given date.

Licensing:

The information on this web page is distributed under the MIT license.

Languages:

weekday is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.

Related Data and Programs:

weekday_test

analemma, a C code which evaluates the equation of time, a formula for the difference between the uniform 24 hour day and the actual position of the sun, by Brian Tung.

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

doomsday, a C code 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.

test_values, a C code which supplies test values of various mathematical functions.

Reference:

1. Lewis Carroll (Charles Dodgson),
   To Find the Day of the Week for Any Given Date,
   Nature, 31 March 1887.
2. Gary Meisters,
   Lewis Carroll's Day-of-the-Week Algorithm,
   Math Horizons,
   November 2002, pages 24-25.
3. Edward Reingold, Nachum Dershowitz,
   Calendrical Calculations: The Millennium Edition,
   Cambridge University Press, 2001,
   ISBN: 0-521-77752-6,
   LC: CE12.R45.
4. Edward Richards,
   Mapping Time, The Calendar and Its History,
   Oxford, 1999,
   ISBN: 0-19-850413-6,
   LC: CE11.R5.

Source Code:

• weekday.c, the source code.
• weekday.sh, compiles the source code.
• weekday.h, the include file.