By default, the x-y axes are scaled equally in ``Image'' mode (If the
-2d flag is supplied at the command line, however, the default mode is ``Normal''). This
makes profile plots in x-z difficult to view especially for high
aspect ratio grids. Hitting the
button with the left
mouse button will toggle between ``image'' mode and ``normal'' mode,
in which the data is scaled to fit the plot area. You can also do
this by hitting the ``a'' key. The middle and right mouse buttons have
no effect here.