;+
; NAME:
;  oc_search_pos_single_sao
;
; PURPOSE: (one line)
;  Searches around a given position in the sao catalog.
;
; DESCRIPTION:
;  This routine is a wrapper to oc_search_pos_fullcat/oc_search_pos_subcat .
;
; CATEGORY:
;  Star catalogs
;
; CALLING SEQUENCE:
;  oc_search_pos_single_sao, RA, DEC, RADIUS, NSTARS, 
;   METHOD=method, _extra=extra
;
; INPUTS:
;  RA     -- Right ascension of center of search position.  Radians, J2000.
;  DEC    -- Declination     of center of search position.  Radians, J2000.
;  RADIUS -- Search radius.  Radians. 
;
;  Inputs are single values, not arrays.
;
; OPTIONAL INPUT PARAMETERS:
;  METHOD -- either 'FULLCAT' or 'SUBCAT', for on search method requested.
;
; KEYWORD INPUT PARAMETERS:
;  /VERBOSE -- If set, print diagnostics to screen.
;  _extra -- Passed on 
;
; KEYWORD OUTPUT PARAMETERS:
;  None
;
; OUTPUTS:
;  result -- Array of structures [nstars], with each element being a 
;    fully-populated star structure containing RA, Dec, magnitude, etc.
;  NSTARS -- Number of stars found
;  
; COMMON BLOCKS:
;  None
;
; SIDE EFFECTS:
;  None
;
; RESTRICTIONS:
;  The proper environment variable must be set for the catalog called.
;   $WCS_CATDIR/sao -- For sao catalog
;
; EXAMPLE:
;  print, (oc_search_pos_single_sao(0.1, 0.1, 0.01, nstars)).ID
;    [Locates three stars]
;
; MODIFICATION HISTORY:
;  Written  10-Nov-2006 by Leslie Young, SwRI
;-

function oc_search_pos_single_sao, ra, dec, radius, nstars
    
    if strlen(getenv('SAO_PATH')) eq 0 then $
      print, 'Warning: SAO_PATH not set.'
    name_catalog= 'sao'
    ids_scat 	= oc_scat(ra, dec, radius, name_catalog, nstars, $
                          verbose=verbose)
    if nstars eq 0 then return, -1L
    ids = long(ids_scat)
    stars= oc_getstar_sao(ids, nstars=nstars, verbose=verbose)
    return, stars
    
end