This instrument mimics a chart recorder. The vertical black lines
are markers that can be moved by clicking and dragging, or by using the
control dials. When you press "calculate delta", the computer shows
the differences between the x-values and the y-values of the marked points
(where the marker intersects the data). The axis scales are controllable,
and one can scroll through a large amount of data.
Last revised by Andrew Smith
November 20, 2000.