;-------------------------------------------------------------
;+
; NAME:
;       PLURAL
; PURPOSE:
;       Plural function: returns 's' if arg > 1, else ''.
; CATEGORY:
; CALLING SEQUENCE:
;       c = plural(n)
; INPUTS:
;       n = a number.                                     in
;       c = returned character: '' if n is 1, else 's'.   out'
; KEYWORD PARAMETERS:
;       Keywords:
;         SINGLE=stxt  Text to return if n is 1, def=''.
;         PLURAL=ptxt  Text to return if n is not 1, def='s'.
; OUTPUTS:
; COMMON BLOCKS:
; NOTES:
;       Notes: Useful to get numeric related messages correct.
;       Examples: print,strtrim(n,2)+' cow'+plural(n)
;        print,strtrim(n,2)+' '+plural(n,single='ox',plural='oxen')
; MODIFICATION HISTORY:
;       R. Sterner, 1995 Dec 14
;
; Copyright (C) 1995, Johns Hopkins University/Applied Physics Laboratory
; This software may be used, copied, or redistributed as long as it is not
; sold and this copyright notice is reproduced on each copy made.  This
; routine is provided as is without any express or implied warranties
; whatsoever.  Other limitations apply as described in the file disclaimer.txt.
;-
;-------------------------------------------------------------
	function plural, n, single=sing, plural=plur, help=hlp
 
	if (n_params(0) lt 1) or keyword_set(hlp) then begin
	  print," Plural function: returns 's' if arg > 1, else ''."
	  print,' c = plural(n)'
	  print,'   n = a number.                                     in'
	  print,"   c = returned character: '' if n is 1, else 's'.   out'
	  print,' Keywords:'
	  print,"   SINGLE=stxt  Text to return if n is 1, def=''."
	  print,"   PLURAL=ptxt  Text to return if n is not 1, def='s'."
	  print,' Notes: Useful to get numeric related messages correct.'
	  print," Examples: print,strtrim(n,2)+' cow'+plural(n)"
	  print,"  print,strtrim(n,2)+' '+plural(n,single='ox',plural='oxen')"
	  return,''
	endif
 
	if n_elements(sing) eq 0 then sing = ''
	if n_elements(plur) eq 0 then plur = 's'
	if n eq 1 then return,sing else return,plur
 
	end