Texas Instruments TI-89 Titanium User Manual page 408

Standard values (set when you select
t0 = 0.
tmax = 10.
tstep = .1
tplot = 0.
You may need to change the standard values for the t variables to ensure that sufficient
points are plotted.
The fldpic System Variable
When a slope or direction field is drawn, a picture of the field is stored automatically to a
system variable named
equations but does not affect the field, the TI-89 Titanium reuses the picture in
instead of having to redraw the field. This can speed up the regraphing time significantly.
is deleted automatically when you exit the differential equation graphing mode or
fldpic
when you display a graph with
Exploring a Graph
As in function graphing, you can explore a graph by using the following tools. Any
displayed coordinates are shown in rectangular or polar form as set in the graph format.
Tool For Differential Equation Graphs:
Free-Moving Works just as it does for function graphs.
Cursor
Differential Equation Graphing
6:ZoomStd
xmin = L 1. ymin =
xmax = 10. ymax = 10.
xscl = 1. yscl = 1.
. If you perform an operation that regraphs the plotted
fldpic
Fields = FLDOFF
from the „
ncurves = 0.
L 10.
diftol = .001
Estep = 1.
fldres = 14.
dtime = 0.
.
toolbar menu) are:
Zoom
fldpic
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