*--   SHANA.TXT
*-----------------------------------------------------------------------------
*--     Author's note about Hebrew-calendar functions:
*--     My main source for these algorithms was "The Comprehensive Hebrew
*--     Calendar" by Arthur Spier, Third Revised Edition, Philipp Feldheim Inc.,
*--     Spring Valley, NY, 1986, but I never could have understood it without
*--     first, the fine materials given me by Dave Krajcar, ("Altsol"), of
*--     Alternative Solutions, Inc., at considerable personal expense and
*--     inconvenience, and second the simplified introduction provided by
*--     "Understanding the Jewish Calendar", by Rabbi Nathan Bushwick,
*--     Moznaim Publishing Corporation, Brooklyn, 1989.  Any mistakes in
*--     applying the algorithms are entirely mine.
*--             The main function in importance is Roshashana ( sorry for
*--     the spelling, but the number of characters allowed in dBASE cannot
*--     exceed 10 ); I have no means of checking whether or not it works
*--     properly for periods outside the period 1900-2100.
*--             If you try to create a calendar, you will find that using
*--     these functions repeatedly is very slow because they are set up to
*--     recalculate Rosh Hashanah from scratch on each call.  This is
*--     required by passing only the year as a parameter and returning only
*--     a date; you can easily adapt them so the date, hour and chalokim
*--     of each Molad Tishri and date of each Rosh Hashanah are saved in
*--     public variables between calls and made available to later calculations.
*--             Note also that given the date and time of one Molad Tishri,
*--     finding the next or previous one requires only adding or subtracting
*--     12 or 13 times the length of a lunar month.  Then, applying the
*--     dechiyoth to the date and time of the Molad Tishri will find Rosh
*--     Hashanah, and the dates of it and its predecessor can be used to find
*--     the kebiah.  Given the kebiah and the date of Rosh Hashanah, the
*--     entire calendar is known and can be constructed from code like that
*--     in the latter part of the Dat2Heb() function.
*--             If using these functions for purposes such as figuring out
*--     when a boy is bar mitzvah, please remember some details: a child born
*--     after sundown has a Hebrew birthday matching the next civil day,
*--     anniversaries of events occurring in Adar follow special rules, and
*--     many congregations postpone the celebration if the birthday falls
*--     on the Sabbath or if the celebration would fall on certain major
*--     Sabbaths.  In addition, see the notes to the Civildate() function
*--     about Heshvan and Kislev 30, particularly in connection with
*--     Yahrzeit, determining the anniversary of a death.
*--             I don't know Hebrew or Yiddish; my sources use different
*--     transliterations of words and I have in some cases used one form,
*--     in others another.  If my spelling, or use of words such as "Hebrew"
*--     that have on too many occasions been used as epithets, gives offense,
*--     I apologize.  Suggest more neutral terms that still convey what it
*--     is these functions do if you can; I look forward to hearing from
*--     you.  Until then, please believe that I approached this from a
*--     sense of awe at a calendar so accurate and so old, and in a spirit
*--     perhaps akin to that quoted by Rabbi Bushwick from the Gemara,
*--     Shabbos 75b, "Anyone who has the ability to calculate the motions
*--     of the heavenly bodies and does not do so is refusing to see the
*--     greatness of God's work."
*--                                     Jay Parsons
*--                                     Bernardsville, NJ
*--                                     March 27, 1993 ( Nisan 5, 5753 )
*--
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