Parameters

  Keyword    Type      Description
  -------    ----      -----------
   NUM       INT       Line number (1 at top)
   TEXT      CHAR      Text of axis label
   FONT      INT       Font number
   BOLD      INT       Character boldness
   SIZE      REAL      Multiple of default character size
   COLOUR    INT       Colour index
   JUST      CHAR      Justification (L, C or R)