II. Setting a Window - Finding One That Works

A. Overview


The ZOOM menu offers you several preset windows and numerous other options. In this section, we will look only at some of the preset windows. There are many times when one of these options will work well with the function you are graphing. To access the ZOOM menu, press . Notice the small arrow at the far right of the menu. This means that the menu has more options, and you can access these by pressing the key.

BOX This allows you to box in a particular area of the graph.
ZIN Zooms in with the center at the point of the cursor.
The default factor is 4.
ZOUT Zooms out with the center at the point of the cursor.
The default factor is 4.
ZSTD This is also a useful window.
The window size is X:[-10, 10] and Y:[-10, 10].
ZPREV Changes the window to the previous settings.
ZFIT Sets a window that shows the maximum and minimum
value of Y with the given X window.
ZSQR Adjusts Xmin and Xmax so that the ticks are the
same distance apart on both axes.
ZTRIG Must be in radians. Preset to a window that is
good for elementary trig functions.
ZDECM This is one of the most useful windows. It is also
called a friendly window because the TRACE key
will move in increments of 0.1 with this window.
The window size is X:[-6.3,6.3] and Y:[-3.1, 3.1].
ZDATA Gives a window that shows all statistical data points.

You can define zoom-window variables using
ZSTO and recall them with this option.

ZFACT Brings up the ZOOM FACTORS screen.
ZOOMX Zooms out by a factor of xFact only and disregards yFact.
ZOOMY Zooms out by a factor of yFact only and disregards xFact.
ZINT Redefines the window to Xscl=10 and Yscl=10.
ZSTO Stores the current window values that can be
recalled using ZRCL.

Some of these presets can give you some strange results, so it is best to use just ZDecimal or ZStandard until you become more proficient when setting windows. Several of these are used in the examples in section B of this module.

B. Examples