%N julcal %F $MIR/src/subs/julday.for
%D Convert a Julian day into a calendar day.
%P jm
%: julian-day, date, utilities
%B
      subroutine julcal(julian,year,month,day)

      implicit none
      double precision julian,day
      integer year,month

  Convert from Julian date to calendar date.  This is not to high
  accuracy, but it achieves the accuracy required.  See "Astronomical
  Formulae for Calculators", Jean Meeus (Wiillmann-Bell Inc).
  The day is assumed to begin at 0 hours UT.

  Input:
    julian     Julian day.
  Output:
    year       Year (e.g. 1990)
    month      Month [1,12].
    day        Day [1-32).
