WEEKDAY\
Determine the Day of the Week {#weekday-determine-the-day-of-the-week align=”center”}
=============================
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: {#licensing align=”center”}
The computer code and data files described and made available on this
web page are distributed under the GNU LGPL
license.
Languages: {#languages align=”center”}
WEEKDAY is available in a C
version and a C++
version and a FORTRAN77
version and a FORTRAN90
version and a MATLAB
version.
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: {#reference align=”center”}
- 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: {#source-code align=”center”}
Examples and Tests: {#examples-and-tests align=”center”}
List of Routines: {#list-of-routines align=”center”}
- 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.