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SUBROUTINE sla_DS2C6 (A, B, R, AD, BD, RD, V)
*+
* - - - - - -
* D S 2 C 6
* - - - - - -
*
* Conversion of position & velocity in spherical coordinates
* to Cartesian coordinates
*
* (double precision)
*
* Given:
* A dp longitude (radians)
* B dp latitude (radians)
* R dp radial coordinate
* AD dp longitude derivative (radians per unit time)
* BD dp latitude derivative (radians per unit time)
* RD dp radial derivative
*
* Returned:
* V dp(6) Cartesian position & velocity vector
*
* P.T.Wallace Starlink 10 July 1993
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION A,B,R,AD,BD,RD,V(6)
DOUBLE PRECISION SA,CA,SB,CB,RCB,X,Y,RBD,W
* Useful functions
SA=SIN(A)
CA=COS(A)
SB=SIN(B)
CB=COS(B)
RCB=R*CB
X=RCB*CA
Y=RCB*SA
RBD=R*BD
W=RBD*SB-CB*RD
* Position
V(1)=X
V(2)=Y
V(3)=R*SB
* Velocity
V(4)=-Y*AD-W*CA
V(5)=X*AD-W*SA
V(6)=RBD*CB+SB*RD
END
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