APPENDIX A - DATE FORMATS

      The following date formats are supported by TCHK:

      TCHK Reference      Date Type                Format
      --------------      ---------                ------
      Greg                Gregorian (US)           MM-DD-YY
      GregEuro            Gregorian (European)     DD-MM-YY
      GregJap             Gregorian (Japan)        YY-MM-DD
      Cal                 Calendar                 YYMMDD
      CalCent             Calendar (w/Century)     YYYYMMDD
      Jul                 Julian (Type E)          special hashed number
      JulA                Julian (Type A)          YYDDD
      JulB                Julian (Type B)          YYYYDDD
      full                English (Full)           Month DD, YYYY
      short               English (Short)          Mon DD, YYYY
      ddate               struct ddate             see datehk.h

      -  Gregorian units are common shorthand dates (in string format)
         with all leading zeros preserved
      -  Calendar units are numeric representations (double)
      -  Julian Type E is a special "magic" hashed number (double)
         representing the number of elapsed days since an initial date.
         Julian Type E numbers are valid for the years 1900-2100 (give
         or take a couple of months)
      -  Julian Type A and B are ANSI defined formats (double)
         containing year (and century for type B) and the day of the
         year
      -  full are strings of the date with the full name of the month
      -  short are strings of the date with the short abbreviation of
         the month
      -  ddate is my own date structure defined in datehk.h

      In some instances date formats not specifically designed to hold
      the century may overflow. For example, converting CalCent
      formatted  20220401 (April 1, 2022) to Greg (MM-DD-YY) would
      result in the string "04-01-122". Be aware.


                           ! ! ! WARNING ! ! !

      Unless otherwise specified, date format conversion functions
      (GregtoCal, JulAtoddate, etc.) do NOT perform error checking. If
      you pass an invalid date (March 32, 1988) your result may be
      logically incorrect even though syntactically correct (Gregorian
      date of 03/32/88) or be totally corrupted.

      Julian Type E numbers are valid for the years 1900-2100 (give or
      take a couple of months.)