Texas Instruments PLUS TI-89 - Manual (Page 136)

Chapter 6: Basic Function Graphing 119
06BASFUN.DOC TI-89/TI-92 Plus: Basic Function Graphing (English) Susan Gullord Revised: 02/23/01 4:09 PM Printed: 02/23/01 4:18 PM Page 119 of 22
Press „ from the Y= Editor, Window Editor, or Graph screen.
Procedures for using ZoomBox ,
ZoomIn , ZoomOut , ZoomStd , Memory ,
and SetFactors are given later in this
section.
For more information about the
other items, refer to Appendix A.
Zoom Tool Description
ZoomBox Lets you draw a box and zoom in on that box.
ZoomIn,
ZoomOut Lets you select a point and zoom in or out by an
amount defined by
SetFactors .
ZoomDec Sets
∆
x and
∆
y to .1, and centers the origin.
ZoomSqr Adjusts Window variables so that a square or circle is
shown in correct proportion (instead of a rectangle
or ellipse).
ZoomStd Sets Window variables to their default values.
xmin = ë 10 ymin = ë 10 xres = 2
xmax = 10 ymax = 10
xscl = 1 yscl = 1
ZoomTrig Sets Window variables to preset values that are often
appropriate for graphing trig functions. Centers the
origin and sets:
∆
x = p /24 (.130899... radians ymin = ë 4
or 7.5 degrees) ymax = 4
xscl = p /2 (1.570796... radians yscl = 0.5
or 90 degrees)
ZoomInt Lets you select a new center point, and then sets
∆
x
and
∆
y to 1 and sets xscl and yscl to 10.
ZoomData Adjusts Window variables so that all selected stat
plots are in view. Refer to Chapter 16.
ZoomFit Adjusts the viewing window to display the full range
of dependent variable values for the selected
functions. In function graphing, this maintains the
current
xmin and xmax and adjusts ymin and ymax .
Memory Lets you store and recall Window variable settings so
that you can recreate a custom viewing window.
SetFactors Lets you set Zoom factors for ZoomIn and ZoomOut .
Using Zooms to Explore a Graph
The „ Zoom toolbar menu has several tools that let you
adjust the viewing window. You can also save a viewing
window for later use.
Overview of the
Zoom Menu
Note: If you select a Zoom
tool from the Y=Editor or
Window Editor, the
TI
- 89 / TI - 92 Plus
automatically displays the
Graph screen.
Note: ∆ x and ∆ y are the
distances from the center of
one pixel to the center of an
adjoining pixel.