SHOW /DIRECTORY

        [DISPLAY\]SHOW Argument [FirstPlane [LastPlane]] /DIRECTORY NameTree
      [/OVERLAY [Variable [Channel]] [/SIDE]

      Display the graphics under the user specified  <NameTree  "graphic  tree",
    instead  of  the usual <GREG tree. The tree is created if needed, cleared if
    it already exists.

    Using different "graphic trees" allows the user  to  simultaneously  display
    (same or different) data in different ways, as each tree inherits a specific
    window.

    A  few names should not be used:  VSIDE, POPUP, CCT because they are already
    used by some specific plotting routine.