;+
; NAME:
;       DRAWBOX
; PURPOSE:
;       Plots a box with a set of coordinates
; CALLING SEQUENCE:
;       drawbox, x1, y1, x2, y2
; EXAMPLES:
;       drawbox, 0, 0, 1, 1
;           Draws a box with corners (0,0), (0,1), (1,1) and (1,0)
; KEYWORDS:
;       Accepts all oplot commands
; MODIFICATION HISTORY:
;       Before 05/06/2007 Written by Eduard Westra
;-
PRO drawbox, x1, y1, x2, y2, _EXTRA=extra
  oplot, [x1, x2, x2, x1, x1], [y1, y1, y2, y2, y1], _EXTRA=extra
END