.help obs Jun99 "Slalib Package"
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      SUBROUTINE slOBS (N, C, NAME, W, P, H)

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      O B S
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  Parameters of selected groundbased observing stations

  Given:
     N       int     number specifying observing station

  Either given or returned
     C       c*(*)   identifier specifying observing station

  Returned:
     NAME    c*(*)   name of specified observing station
     W       dp      longitude (radians, West +ve)
     P       dp      geodetic latitude (radians, North +ve)
     H       dp      height above sea level (metres)

  Notes:

     Station identifiers C may be up to 10 characters long,
     and station names NAME may be up to 40 characters long.

     C and N are alternative ways of specifying the observing
     station.  The C option, which is the most generally useful,
     may be selected by specifying an N value of zero or less.
     If N is 1 or more, the parameters of the Nth station
     in the currently supported list are interrogated, and
     the station identifier C is returned as well as NAME, W,
     P and H.

     If the station parameters are not available, either because
     the station identifier C is not recognized, or because an
     N value greater than the number of stations supported is
     given, a name of '?' is returned and C, W, P and H are left
     in their current states.

     Programs can obtain a list of all currently supported
     stations by calling the routine repeatedly, with N=1,2,3...
     When NAME='?' is seen, the list of stations has been
     exhausted.

     Station numbers, identifiers, names and other details are
     subject to change and should not be hardwired into
     application programs.

     All station identifiers C are uppercase only;  lowercase
     characters must be converted to uppercase by the calling
     program.  The station names returned may contain both upper-
     and lowercase.  All characters up to the first space are
     checked;  thus an abbreviated ID will return the parameters
     for the first station in the list which matches the
     abbreviation supplied, and no station in the list will ever
     contain embedded spaces.  C must not have leading spaces.

     IMPORTANT -- BEWARE OF THE LONGITUDE SIGN CONVENTION.  The
     longitude returned by slOBS is west-positive in accordance
     with astronomical usage.  However, this sign convention is
     left-handed and is the opposite of the one used by geographers;
     elsewhere in SLALIB the preferable east-positive convention is
     used.  In particular, note that for use in slAOP, slAOPA
     and slOAP the sign of the longitude must be reversed.

     Users are urged to inform the author of any improvements
     they would like to see made.  For example:

         typographical corrections
         more accurate parameters
         better station identifiers or names
         additional stations

  P.T.Wallace   Starlink   21 April 1999

  Copyright (C) 1999 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

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