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# jdcalf

erfa.jdcalf(ndp, dj1, dj2)

  Julian Date to Gregorian Calendar, expressed in a form convenient for formatting messages: rounded to a specified precision.

  Parameters:
    ndp int array
    dj1 double array
    dj2 double array
  Returns:
    iymdf int array

  Notes

  Wraps ERFA function `eraJdcalf`. The ERFA documentation is:

      - - - - - - - - - -
       e r a J d c a l f
      - - - - - - - - - -

      Julian Date to Gregorian Calendar, expressed in a form convenient
      for formatting messages:  rounded to a specified precision.

      Given:
         ndp       int      number of decimal places of days in fraction
         dj1,dj2   double   dj1+dj2 = Julian Date (Note 1)

      Returned:
         iymdf     int[4]   year, month, day, fraction in Gregorian
                            calendar

      Returned (function value):
                   int      status:
                              -1 = date out of range
                               0 = OK
                              +1 = ndp not 0-9 (interpreted as 0)

      Notes:

      1) The Julian Date is apportioned in any convenient way between
         the arguments dj1 and dj2.  For example, JD=2450123.7 could
         be expressed in any of these ways, among others:

                 dj1            dj2

             2450123.7           0.0       (JD method)
             2451545.0       -1421.3       (J2000 method)
             2400000.5       50123.2       (MJD method)
             2450123.5           0.2       (date & time method)

      2) In early eras the conversion is from the "Proleptic Gregorian
         Calendar";  no account is taken of the date(s) of adoption of
         the Gregorian Calendar, nor is the AD/BC numbering convention
         observed.

      3) See also the function eraJd2cal.

      4) The number of decimal places ndp should be 4 or less if internal
         overflows are to be avoided on platforms which use 16-bit
         integers.

      Called:
         eraJd2cal    JD to Gregorian calendar

      Reference:

         Explanatory Supplement to the Astronomical Almanac,
         P. Kenneth Seidelmann (ed), University Science Books (1992),
         Section 12.92 (p604).

      This revision:  2023 January 16

      Copyright (C) 2013-2023, NumFOCUS Foundation.
      Derived, with permission, from the SOFA library.  See notes at end of file.