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SUBROUTINE sla_NUT (DATE, RMATN)
*+
* - - - -
* N U T
* - - - -
*
* Form the matrix of nutation for a given date - IAU 1980 theory
* (double precision)
*
* References:
* Final report of the IAU Working Group on Nutation,
* chairman P.K.Seidelmann, 1980.
* Kaplan,G.H., 1981, USNO circular no. 163, pA3-6.
*
* Given:
* DATE dp TDB (loosely ET) as Modified Julian Date
* (=JD-2400000.5)
* Returned:
* RMATN dp(3,3) nutation matrix
*
* The matrix is in the sense V(true) = RMATN * V(mean)
*
* Called: sla_NUTC, sla_DEULER
*
* P.T.Wallace Starlink 1 January 1993
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION DATE,RMATN(3,3)
DOUBLE PRECISION DPSI,DEPS,EPS0
* Nutation components and mean obliquity
CALL sla_NUTC(DATE,DPSI,DEPS,EPS0)
* Rotation matrix
CALL sla_DEULER('XZX',EPS0,-DPSI,-(EPS0+DEPS),RMATN)
END
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