This demo includes two windows: a control window (which contains the equation for f(x, y) in this case) and a 2D graph window. You may find it useful to adjust the size of the graph window.
Once you are comfortable with the window size, you can translate or zoom in or out to change your view of the 2D graph.
To translate, select Translate from the Tools menu or hold down Alt. Click and drag in the direction you want to translate the graph.
To zoom, select Zoom from the Tools menu or hold down Shift. Click and drag upward to zoom in or drag downward to zoom out.
When you are finished using the demo, you can exit by closing the control window or by selecting Exit Demo from the Demo menu in the control window.