Texas Instruments Titanium TI-89, User Manual

Page: 409 / 977

Differential Equation Graphing 406
Note:
During a trace, you can move the cursor to a particular point by typing a value for t
and pressing
¸
. You can use QuickCenter at any time during a trace, even if the
cursor is still on the screen.
„
Zoom
Works just as it does for function graphs.
• Only
x
(
xmin
,
xmax
,
xscl
) and
y
(
ymin
,
ymax
,
yscl
)
Window variables are affected.
• The t Window variables ( t0 , tmax , tstep , tplot ) are not
affected unless you select
6:ZoomStd
(which sets all
Window variables to their standard values).
…
Trace
Lets you move the cursor along the curve one tstep at a
time. To move approximately ten plotted points at a time,
press
2 B
or
2 A
.
If you enter initial conditions in the Y= Editor or let the
ncurves Window variable plot curves automatically, you
can trace the curves. If you use:
@ 2
Š
IC from the Graph screen to select initial conditions
interactively, you cannot trace the curves.
QuickCenter applies to all directions. If you move the
cursor off the screen (top or bottom, left or right), press
¸
to center the viewing window on the cursor location.
Use
C
or
D
to view results on all plotted curves.
‡
Math
Only 1:Value is available.
• With TIME axes, the
y(t)
solution value (represented by
yc) is displayed for a specified t value.
• With CUSTOM axes, the values that correspond to x and
y depend on the axes you choose.
Tool For Differential Equation Graphs: