PANEL

          GUI\PANEL  "Title"  HelpFile [/DETACH]

    Activate the Graphic-User-Interface input mode for variables.  A  window
    with  the  specified  title  is  created,  but not mapped to the screen.
    Successive LET commands will create widgets in this window to  allow  to
    modify  variables  by  entering  values  in  the widgets. Command GUI\GO
    "Command" will map the window to the screen.  Once the proper input  has
    been  defined,  clicking  on  the "GO" button will setup all the related
    variables in the main  program,  and  execute  the  associated  command.
    Clicking  on  button  "UPDATE"  will only set the variables. Clicking on
    button "ABORT" will return without modifying the variables.

    Help is available in the window through  the  "HELP"  button,  but  also
    clicking in any prompt area.

    See LET command for details.

    If option /DETACH is present, a menubar is created instead of  a  normal
    window.  Several  buttons  can  be  attached  to  this menubar using the
    GUI\BUTTON and GUI\MENU commands, but no variables can be  set  in  this
    mode. The menubar is mapped when command GUI\GO is typed.