1 COMMENT
  Syntax: COMMENT command [ncomm]
      or  COMMENT id [&idb] command [ncomm]
          text
          x, y, size, angle, option, mode, font, colour, thickness
   where:  id        is the histogram number the comment applies to
           idb       is the optional secondary identifier
           command   can be ?|NEW|CHANGE|DELETE|LIST|END
           ncomm     is the comment number to change or delete
           text      is the text you want to display
           x,y       are the position of the comment
           size      is the size of the text in cm (default = 0.4cm)
           angle     is in degrees with respect to the horizontal
           option    can be: LEFT   Comment is left adjusted
                             CENTRE Comment is centered
                             RIGHT  Comment is right adjusted (default)
           mode      can be: CM   = Position is in cm (default)
                             PLOT = Position in terms of plot coordinates
           font      is the font to use
           colour    is the colour number for the comment
           thickness is the text thickness factor

  When the `COMMENT'  command is given in a file  or a defined command the
  last syntax must always be used and  the comment number must be given if
  it is applicable to the command  (`CHANGE' or `DELETE'). You always need
  the `END' command when reading from  a file to exit `COMMENT' unless you
  give the `command' on the same line as `COMMENT'.

  Comments are associated with histograms you have already plotted.
  Therefore, if you have only plotted one histogram on the picture
  (using the `PLOT', `2DIM', `LEGO', `SURFACE', `DISPLAY' or
  `OVERLAY/DIFF' commands - `OVERLAYS' on the same scale do not
  count), the syntax is the first line. If you have plotted more than
  one histogram on the display you will be prompted for the identifier
  the comment applies to.

  If you just give  the command  `COMMENT' or `COMMENT  id[&idb]' you will
  remain in `COMMENT' until you give the `END' command or `<CR>'. However,
  if you give some or all of the rest of the `COMMENT' command on the same
  line you will  automatically exit `COMMENT'  after you have finished the
  command.

  By default the text will be written using the HIGZ routine
  IGTEXT. For details on formatting text and the other fonts available
  see HELP Text. The default colour and thickness of the comments are
  the same as the title.

  If you use the option `SET MOUSE ON', then the position of the comment
  is specified by the mouse. Move the mouse to where you want to have the
  comment and click on the left button. To keep the comment in the same
  position (if you are changing it) click on the right mouse button.
  Note that using the mouse only works properly in `CM' mode.

  You can omit all of the parameters except `x' and `y' for a new comment.
  For `mode CM', `x=0, y=0' is the  bottom left-hand corner of the picture
  If you change or  delete a comment  use the command  `REDRAW' to see the
  effect of what you have done.

