

     Quick notes on DMSJUL

         A recent request by a registered user to our BBS (The File Bank)
         inspired me to put together these Julian to/from calendar date
         conversion routines. These UDFs are the result of a concept
         presented by Luis A. Castro in the book 'Advanced Programmers'
         Guide' published by Ashton-Tate.

         Luis explains the Julian calendar period as:

         "...the Julian period was devised in 1582 by Joseph Caliger and
         named after his father Julius, not after Julius Caesar or the
         Julian calendar. Scaliger began the first Julian Day at noon,
         January 1, 4713 B.C., the most recent time that three major
         chronological cycles began on the same day: the twenty-eight-year
         solar cycle, the ninteen-year lunar cycle, and the fifteen-year
         indication cycle. It will take to the year 3267 to complete the
         period, a total of 7,980 years which is the product of
         twenty-eight, nineteen, and fifteen..."

         These UDFs were written with Clipper's date ranges in mind:
         01/01/0100 - 12/31/2999 (36,160 - 1,095,384 Julian). Dealing with
         dates outside these limits didn't seem practical, but who am I to
         say ?? If you need to extend the range, give me a holler - I've
         some thoughts on how it could work. (it would involve using
         character expressions for the dates, as opposed to true date
         expressions).

         If you plan to deal with only twentieth century dates, then you
         will not require SET CENTURY ON (see DEMOJUL.PRG for more info on
         this).


         The following files should have been included in DMSJUL.ZIP

              DMSJUL   PRG   CAL2JUL() - calendar to Julian conversion UDF
                             JUL2CAL() - Julian to calendar conversion UDF

              DEMOJUL  PRG   demonstrates the above UDFs
              README         this file


     Can't Wait ???

         Compile the demonstration program (DEMOJUL) and have CLIPPER.LIB,
         EXTEND.LIB available to the linker:

              CLIPPER DEMOJUL

              TLINK DEMOJUL,,,CLIPPER EXTEND          (TLINK)

              PLINK86 FI DEMOJUL LIB CLIPPER, EXTEND  (PLINK86)


     Legal, rights, & other stuff

         DMSJUL, as distributed in it's present form, is a copyrighted
         product.  It is not released into the public domain. Data
         Management Systems reserves all rights to DMSJUL as provided by US
         Copyright laws. You may use DMSJUL in your applications, both
         personal and commercial, without royalty obligations.

         Although a great deal of time and effort have been spent
         designing, coding and debugging this utility, it cannot be certain
         that it is totally error free. It should be clearly understood
         that DMJUL is released "as is". Data Management Systems makes no
         warranties, expressed nor implied, of merchantability and fitness
         for a particular purpose. In no event shall Data Management
         Systems be liable for any direct, indirect, or consequential
         damages, real or imagined.


     Data Management Systems ??

         We are a custom software house located in Fallbrook, California.
         Founded in 1983, our primary vehicle of development is Clipper. We
         also provide value added sales, consulting, training, and data
         processing.


         Please send any comments, suggestions, or gripes to:

              Bob Laszko
              Data Management Systems
              PO Box 3104
              Fallbrook, Ca  92028
              (619) 728-0984
              CIS 76327,420


         BBS support is provided via The File Bank's Clipper Support
         Conference. This is one of the premier BBS's in Southern
         California with something of interest from the novice to the guru
         !! As of this writing, The File Bank boasts over 1,500 users from
         ten countries, 3,000+ files (1,000+ Clipper related), and hosts
         the Clipper Conference on the PCRelay echo system. We've just
         installed a third node (two public, one registered - all HST
         19,200) running under LANtastic (we're dealers for LANtastic and
         Perstor hard disk controllers as well). You can reach The File
         Bank at (619) 728-4318.