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+ SUBROUTINE sla_MAPQKZ (RM, DM, AMPRMS, RA, DA)
+*+
+* - - - - - - -
+* M A P Q K Z
+* - - - - - - -
+*
+* Quick mean to apparent place: transform a star RA,Dec from
+* mean place to geocentric apparent place, given the
+* star-independent parameters, and assuming zero parallax
+* and proper motion.
+*
+* Use of this routine is appropriate when efficiency is important
+* and where many star positions, all with parallax and proper
+* motion either zero or already allowed for, and all referred to
+* the same equator and equinox, are to be transformed for one
+* epoch. The star-independent parameters can be obtained by
+* calling the sla_MAPPA routine.
+*
+* The corresponding routine for the case of non-zero parallax
+* and proper motion is sla_MAPQK.
+*
+* The reference frames and timescales used are post IAU 1976.
+*
+* Given:
+* RM,DM d mean RA,Dec (rad)
+* AMPRMS d(21) star-independent mean-to-apparent parameters:
+*
+* (1-4) not used
+* (5-7) heliocentric direction of the Earth (unit vector)
+* (8) (grav rad Sun)*2/(Sun-Earth distance)
+* (9-11) ABV: barycentric Earth velocity in units of c
+* (12) sqrt(1-v**2) where v=modulus(ABV)
+* (13-21) precession/nutation (3,3) matrix
+*
+* Returned:
+* RA,DA d apparent RA,Dec (rad)
+*
+* References:
+* 1984 Astronomical Almanac, pp B39-B41.
+* (also Lederle & Schwan, Astron. Astrophys. 134,
+* 1-6, 1984)
+*
+* Notes:
+*
+* 1) The vectors AMPRMS(2-4) and AMPRMS(5-7) are referred to the
+* mean equinox and equator of epoch EQ.
+*
+* 2) Strictly speaking, the routine is not valid for solar-system
+* sources, though the error will usually be extremely small.
+* However, to prevent gross errors in the case where the
+* position of the Sun is specified, the gravitational
+* deflection term is restrained within about 920 arcsec of the
+* centre of the Sun's disc. The term has a maximum value of
+* about 1.85 arcsec at this radius, and decreases to zero as
+* the centre of the disc is approached.
+*
+* Called: sla_DCS2C, sla_DVDV, sla_DMXV, sla_DCC2S, sla_DRANRM
+*
+* P.T.Wallace Starlink 18 March 1999
+*
+* Copyright (C) 1999 Rutherford Appleton Laboratory
+*-
+
+ IMPLICIT NONE
+
+ DOUBLE PRECISION RM,DM,AMPRMS(21),RA,DA
+
+ INTEGER I
+
+ DOUBLE PRECISION GR2E,AB1,EHN(3),ABV(3),
+ : P(3),PDE,PDEP1,W,P1(3),P1DV,
+ : P1DVP1,P2(3),P3(3)
+
+ DOUBLE PRECISION sla_DVDV,sla_DRANRM
+
+
+
+
+* Unpack scalar and vector parameters
+ GR2E = AMPRMS(8)
+ AB1 = AMPRMS(12)
+ DO I=1,3
+ EHN(I) = AMPRMS(I+4)
+ ABV(I) = AMPRMS(I+8)
+ END DO
+
+* Spherical to x,y,z
+ CALL sla_DCS2C(RM,DM,P)
+
+* Light deflection
+ PDE = sla_DVDV(P,EHN)
+ PDEP1 = PDE+1D0
+ W = GR2E/MAX(PDEP1,1D-5)
+ DO I=1,3
+ P1(I) = P(I)+W*(EHN(I)-PDE*P(I))
+ END DO
+
+* Aberration
+ P1DV = sla_DVDV(P1,ABV)
+ P1DVP1 = P1DV+1D0
+ W = 1D0+P1DV/(AB1+1D0)
+ DO I=1,3
+ P2(I) = (AB1*P1(I)+W*ABV(I))/P1DVP1
+ END DO
+
+* Precession and nutation
+ CALL sla_DMXV(AMPRMS(13),P2,P3)
+
+* Geocentric apparent RA,Dec
+ CALL sla_DCC2S(P3,RA,DA)
+ RA = sla_DRANRM(RA)
+
+ END