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diff --git a/Master/texmf-dist/tex/generic/genmisc/dayofweek.tex b/Master/texmf-dist/tex/generic/genmisc/dayofweek.tex new file mode 100644 index 00000000000..4ce46ac2434 --- /dev/null +++ b/Master/texmf-dist/tex/generic/genmisc/dayofweek.tex @@ -0,0 +1,149 @@ +% +% \DayOfWeek expands to the day of the week ("Sunday", etc.) +% \PhaseOfMoon expands to the phase of the moon +% +% Written by Martin Minow of DEC (minow%bolt.dec@decwrl.dec.com). +% +\def\DayOfWeek{% +% +% Calculate day of the week, return "Sunday", etc. +% + \newcount\dow % Gets day of the week + \newcount\leap % Leap year fingaler + \newcount\x % Temp register + \newcount\y % Another temp register +% leap = year + (month - 14)/12; + \leap=\month \advance\leap by -14 \divide\leap by 12 + \advance\leap by \year +% dow = (13 * (month + 10 - (month + 10)/13*12) - 1)/5 + \dow=\month \advance\dow by 10 + \y=\dow \divide\y by 13 \multiply\y by 12 + \advance\dow by -\y \multiply\dow by 13 \advance\dow by -1 \divide\dow by 5 +% dow += day + 77 + 5 * (leap % 100)/4 + \advance\dow by \day \advance\dow by 77 + \x=\leap \y=\x \divide\y by 100 \multiply\y by 100 \advance\x by -\y + \multiply\x by 5 \divide\x by 4 \advance\dow by \x +% dow += leap / 400 + \x=\leap \divide\x by 400 \advance\dow by \x +% dow -= leap / 100 * 2; +% dow = (dow % 7) + \x=\leap \divide\x by 100 \multiply\x by 2 \advance\dow by -\x + \x=\dow \divide\x by 7 \multiply\x by 7 \advance\dow by -\x + \ifcase\dow Sunday\or Monday\or Tuesday\or Wednesday\or + Thursday\or Friday\or Saturday\fi +} +%% +%% +%% +\def\PhaseOfMoon{% Calculate the phase of the (civil) moon. +% +% The routine calculates the year's epact (the age of the moon on Jan 1.), +% adds this to the number of days in the year, and calculates the phase +% of the moon for this date. It returns the phase as a string, e.g., +% "new", "full", etc. +% +% In the algorithm: +% +% diy Is the day of the year - 1 (i.e., Jan 1 is day 0). +% +% golden Is the number of the year in the Mentonic cycle, used to +% determine the position of the calender moon. +% +% epact Is the age of the calender moon (in days) at the beginning +% of the year. To calculate epact, two century-based +% corrections are applied: +% Gregorian: (3 * cent)/4 - 12 +% is the number of years such as 1700, 1800 when +% leap year was not held. +% Clavian: (((8 * cent) + 5) / 25) - 5 +% is a correction to the Mentonic cycle of about +% 8 days every 2500 years. Note that this will +% overflow 16 bits in the year 409600. Beware. +% +% The algorithm is accurate for the Gregorian calender only. +% +% The magic numbers used in the phase calculation are as follows: +% 29.5 The moon's period in days. +% 177 29.5 scaled by 6 +% 22 (29.5 / 8) scaled by 6 (this gets the phase) +% 11 ((29.5 / 8) / 2) scaled by 6 +% +% Theoretically, this should yield a number in the range 0 .. 7. However, +% two days per year, things don't work out too well. +% +% Epact is calculated by the algorithm given in Knuth vol. 1 (calculation +% of Easter). See also the article on Calenders in the Encyclopaedia +% Britannica and Knuth's algorithm in CACM April 1962, page 209. +% + \newcount\cent % Century number (1979 == 20) + \newcount\epact % Age of the moon on Jan. 1 + \newcount\diy % Day in the year + \newcount\golden % Moon's golden number + \newcount\x % Temp + \newcount\m % Temp for modulus + \diy=\day \advance\diy by \ifcase\month % Jan 1 == 0 + -1\or -1\or 30\or 58\or 89\or 119\or 150\or % Jan .. Jun + 180\or 211\or 241\or 272\or 303\or 333\fi % Jul .. Dec +% if ((month > 2) && ((year % 4 == 0) && +% ((year % 400 == 0) || (year % 100 != 0)))) +% diy++; /* Leapyear fixup */ + \ifnum \month>2 + \x=\year \m=\x \divide\m by 4 \multiply\m by 4 \advance\x by -\m + \ifnum \x=0 % month > 2 and maybe leapyear + \x=\year \m=\x \divide\m by 400 \multiply\m by 400 \advance\x by -\m + \ifnum \x=0 % 2000 is a leap year + \advance\diy by 1 % so it's one day later + \else % not 2000, check other '00's + \x=\year \m=\x \divide\m by 100 \multiply\m by 100 \advance\x by -\m + \ifnum \x>0 % not some other '00' year + \advance\diy by 1 % it's still one day later + \fi % not odd century + \fi % not 2000-type century + \fi % not leapish year + \fi % not march or later +% cent = (year / 100) + 1; /* Century number */ +% golden = (year % 19) + 1; /* Golden number */ + \cent=\year \divide\cent by 100 \advance\cent by 1 + \golden=\year + \m=\year \divide\m by 19 \multiply\m by 19 \advance\golden by -\m + \advance\golden by 1 +% epact = ((11 * golden) + 20 /* Golden number */ +% + (((8 * cent) + 5) / 25) - 5 /* 400 year cycle */ +% - (((3 * cent) / 4) - 12)) % 30;/* Leap year correction */ + \epact=11 \multiply\epact by \golden + \advance\epact by 20 + \x=8 \multiply\x by \cent \advance\x by 5 + \divide\x by 25 \advance\x by -5 + \advance\epact by \x + \x=3 \multiply\x by \cent \divide\x by 4 \advance\x by -12 + \advance\epact by -\x + \m=\epact \divide\m by 30 \multiply\m by 30 \advance\epact by -\m +% if (epact <= 0) +% epact += 30; /* Age range is 1 .. 30 */ +% if ((epact == 25 && golden > 11) || epact == 24) +% epact++; + \ifnum \epact<0 + \advance\epact by 30 + \fi + \ifnum \epact=25 + \ifnum \golden>11 + \advance \epact by 1 + \fi + \else + \ifnum \epact=24 + \advance \epact by 1 + \fi + \fi +% +% Calculate the phase, using the magic numbers defined above. +% Note that phase may be equal to 8 (== 0) on two days of the year +% due to the way the algorithm was implemented. +% phase = (((((diy + epact) * 6) + 11) % 177) / 22) & 7; +% + \x=\diy \advance\x by \epact \multiply\x by 6 \advance\x by 11 + \m=\x \divide\m by 177 \multiply\m by 177 \advance\x by -\m + \divide\x by 22 + \ifcase\x new\or waxing crescent\or in its first quarter\or + waxing gibbous\or full\or waning gibbous\or + in its last quarter\or waning crescent\or new\fi +} |