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SUBROUTINE slSUET (RC, DC, EQ, RM, DM)
*+
* - - - - - -
* S U E T
* - - - - - -
*
* Remove the E-terms (elliptic component of annual aberration)
* from a pre IAU 1976 catalogue RA,Dec to give a mean place
* (double precision)
*
* Given:
* RC,DC dp RA,Dec (radians) with E-terms included
* EQ dp Besselian epoch of mean equator and equinox
*
* Returned:
* RM,DM dp RA,Dec (radians) without E-terms
*
* Called:
* slETRM, slDS2C, sla_,DVDV, slDC2S, slDA2P
*
* Explanation:
* Most star positions from pre-1984 optical catalogues (or
* derived from astrometry using such stars) embody the
* E-terms. This routine converts such a position to a
* formal mean place (allowing, for example, comparison with a
* pulsar timing position).
*
* Reference:
* Explanatory Supplement to the Astronomical Ephemeris,
* section 2D, page 48.
*
* P.T.Wallace Starlink 10 May 1990
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*
* License:
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (see SLA_CONDITIONS); if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*
* Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
*-
IMPLICIT NONE
DOUBLE PRECISION RC,DC,EQ,RM,DM
DOUBLE PRECISION slDA2P,slDVDV
DOUBLE PRECISION A(3),V(3),F
INTEGER I
* E-terms
CALL slETRM(EQ,A)
* Spherical to Cartesian
CALL slDS2C(RC,DC,V)
* Include the E-terms
F=1D0+slDVDV(V,A)
DO I=1,3
V(I)=F*V(I)-A(I)
END DO
* Cartesian to spherical
CALL slDC2S(V,RM,DM)
* Bring RA into conventional range
RM=slDA2P(RM)
END
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