| 
            pltext
          ( | ); | 
      Sets an interactive device to text mode, used in conjunction with
      plgra to allow graphics and text to be interspersed.  On a device
      which supports separate text and graphics windows, this command
      causes control to be switched to the text window.  This can be useful
      for printing diagnostic messages or getting user input, which would
      otherwise interfere with the plots.  The program
      must switch back to the graphics window before
      issuing plot commands, as the text (or console) device will probably
      become quite confused otherwise.  If already in text mode, this
      command is ignored.  It is also ignored on devices which only support
      a single window or use a different method for shifting focus (see
      also plgra).
    
      Redacted form: pltext()
    
This function is used in example 1.