WEEKDAY
Determine the Day of the Week
WEEKDAY
is a C++ library which
can determine the day of the week corresponding to a given date;
for instance, the battle of Hastings, on 14 October 1066 (Julian Calendar!),
was a Saturday.
Licensing:
The computer code and data files described and made available on this web page
are distributed under
the GNU LGPL license.
Languages:
WEEKDAY 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:
CALENDAR_NYT,
a FORTRAN90 library which
shows the correspondence between dates and the New York Times volume and
issue number;
CALENDAR_RD,
a C++ program which
computes the representation of a given date in a
number of calendrical systems,
by Edward Reingold, Nachum Dershowitz
CALPAK,
a C++ library which
makes various calendar calculations;
DATES,
a dataset directory which
contains lists of dates in various calendar systems.
DOOMSDAY,
a C++ 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.
TEST_VALUES,
a C++ library which
supplies test values of various mathematical functions.
Reference:
-
Lewis Carroll (Charles Dodgson),
To Find the Day of the Week for Any Given Date,
Nature, 31 March 1887.
-
Gary Meisters,
Lewis Carroll's Day-of-the-Week Algorithm,
Math Horizons,
November 2002, pages 24-25.
-
Edward Reingold, Nachum Dershowitz,
Calendrical Calculations: The Millennium Edition,
Cambridge University Press, 2001,
ISBN: 0-521-77752-6,
LC: CE12.R45.
-
Edward Richards,
Mapping Time, The Calendar and Its History,
Oxford, 1999,
ISBN: 0-19-850413-6,
LC: CE11.R5.
Source Code:
Examples and Tests:
List of Routines:
-
DIGIT_TO_CH returns the base 10 digit character corresponding to a digit.
-
I4_MAX returns the maximum of two I4's.
-
I4_MIN returns the minimum of two I4's.
-
I4_MODP returns the nonnegative remainder of I4 division.
-
I4_WRAP forces an I4 to lie between given limits by wrapping.
-
JED_TO_WEEKDAY computes the day of the week from a JED.
-
R8_ABS returns the absolute value of an R8.
-
R8_MOD returns the remainder of R8 division.
-
R8_NINT returns the nearest integer to an R8.
-
TIMESTAMP prints the current YMDHMS date as a time stamp.
-
WEEKDAY_TO_NAME_COMMON returns the name of a Common weekday.
-
WEEKDAY_VALUES returns the day of the week for various dates.
-
Y_COMMON_TO_ASTRONOMICAL converts a Common year to an Astronomical year.
-
YMD_TO_S_COMMON writes a Common YMD date into a string.
-
YMD_TO_WEEKDAY_COMMON returns the weekday of a Common YMD date.
-
YMD_TO_WEEKDAY_ENGLISH returns the weekday of an English YMD date.
-
YMDF_COMPARE compares two YMDF dates.
-
YMDF_TO_JED_COMMON converts a Common YMDF date to a JED.
-
YMDF_TO_JED_ENGLISH converts an English YMDF date to a JED.
-
YMDF_TO_JED_GREGORIAN converts a Gregorian YMDF date to a JED.
-
YMDF_TO_JED_JULIAN converts a Julian YMDF date to a JED.
You can go up one level to
the C++ source codes.
Last revised on 25 March 2010.