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.help dcs2c Jun99 "Slalib Package"
.nf

      SUBROUTINE slDS2C (A, B, V)

     - - - - - -
      D S 2 C
     - - - - - -

  Spherical coordinates to direction cosines (double precision)

  Given:
     A,B       dp      spherical coordinates in radians
                        (RA,Dec), (Long,Lat) etc

  Returned:
     V         dp(3)   x,y,z unit vector

  The spherical coordinates are longitude (+ve anticlockwise
  looking from the +ve latitude pole) and latitude.  The
  Cartesian coordinates are right handed, with the x axis
  at zero longitude and latitude, and the z axis at the
  +ve latitude pole.

  P.T.Wallace   Starlink   October 1984

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

.fi
.endhelp