Texas Instruments TI-89 Titanium User Manual page 411

If You Do Not Enter an Initial Condition in the Y= Editor
If you do not enter initial conditions, the
the number of solution curves graphed automatically. By default,
enter a value from 0 through 10. However, the
determine whether
If Fields = Then:
SLPFLD Uses ncurves, if not set to 0, to graph curves.
DIRFLD Ignores ncurves. Does not graph any curves.
FLDOFF Uses ncurves if Axes = TIME (or if Axes = Custom and the
x axis is t). Otherwise, a Diff Eq setup error occurs.
When is used,
ncurves
the value of as set in the Y= Editor or Window Editor is not changed.
t0
Notes:
• Without entering initial conditions, use SLPFLD (with
display a slope or direction field only.
• SLPFLD is for a single 1st-order equation only. DIRFLD is for a 2nd-order equation
(or system of two 1st-order equations) only.
Differential Equation Graphing
is used.
ncurves
is set temporarily at the middle of the Graph screen. However,
t0
Window variable (8 $) specifies
ncurves
graph format and the
Fields
ncurves=0
. You can
ncurves = 0
setting
Axes
) or DIRFLD to
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