Chapter 9: Sequence Graphing 143
09SEQUEN.DOC TI-89/TI-92 Plus: Sequence Graphing (English) Susan Gullord Revised: 02/23/01 10:59 AM Printed: 02/23/01 2:14 PM Page 143 of 14
With TIME and WEB axes, the TI-89 / TI-92 Plus graphs only the
selected sequences. If you entered any sequences that require an
initial value, you must enter the corresponding ui value.
With CUSTOM axes, when you specify a sequence in the custom
settings, it is graphed regardless of whether it is selected.
Only the Line, Dot, Square, and Thick styles are available for sequence
graphs. Dot and Square mark only those discrete integer values (in
plotstep increments) at which a sequence is plotted.
The Window Editor maintains an independent set of Window
variables for each Graph mode setting (just as the Y= Editor
maintains independent function lists). Sequence graphs use the
following Window variables.
Variable Description
nmin, nmax Smallest and largest n values to evaluate. Sequences
are evaluated at:
u(nmin)
u(nmin+1)
u(nmin+2)
... not to exceed ...
u(nmax)
plotStrt The term number that will be the first one plotted
(depending on plotstep). For example, to begin plotting
with the 2nd term in the sequence, set plotstrt = 2. The
first term will be evaluated at nmin but not plotted.
plotStep Incremental n value for graphing only. This does not
affect how the sequence is evaluated, only which points
are plotted. For example, suppose plotstep = 2. The
sequence is evaluated at each consecutive integer but
is plotted at only every other integer.
xmin, xmax,
ymin, ymax
Boundaries of the viewing window.
xscl, yscl Distance between tick marks on the x and y axes.
Selecting
Sequences
Note: With
TIME
and
CUSTOM
axes, all defined
sequences are evaluated
even if they are not plotted.
Selecting the
Display Style
Window Variables
Note: Both nmin and nmax
must be positive integers,
although
nmin
can be zero.
Note: nmin, nmax, plotstrt
and plotstep must be
integers ‚ 1. If you do not
enter integers, they will be
rounded to integers.
You can select a sequence.
You cannot select its
initial value.