Zoom - HP 39g Master Manual

Firstly, one can change the start value and the step size for the view.
NumStart & NumStep
For example, values of 10 and 2 give:
Automatic vs. Build Your Own
Looking at the NUM SETUP view you will see an entry called NumType: with
the default value of Automatic. The only alternative to Automatic is the
setting of Build Your Own. Under this setting the NUM view will be empty,
waiting for you to enter your own values for X.
Typing in the values of (for example):
3 (ENTER) -2 (ENTER) 5 (ENTER)
... will give...
In this situation the function values are being calculated as you input the X
values. This can be quite useful if you are wanting to evaluate the behavior
of a function at selected points.

ZOOM

If you now use the NUM SETUP view to switch
to Automatic you will find that there is a
key at the bottom left of the NUM view. This
can be quite useful as a fast way to reset the
scale.
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