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      SUBROUTINE slECMA (DATE, RMAT)

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      E C M A
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  Form the equatorial to ecliptic rotation matrix - IAU 1980 theory
  (double precision)

  Given:
     DATE     dp         TDB (loosely ET) as Modified Julian Date
                                            (JD-2400000.5)
  Returned:
     RMAT     dp(3,3)    matrix

  Reference:
     Murray,C.A., Vectorial Astrometry, section 4.3.

  Note:
    The matrix is in the sense   V(ecl)  =  RMAT * V(equ);  the
    equator, equinox and ecliptic are mean of date.

  Called:  slDEUL

  P.T.Wallace   Starlink   23 August 1996

  Copyright (C) 1996 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

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