Texas Instruments TI-89 - Page 467

450 Appendix A: Functions and Instructions
8992APPA.DOC TI-89 / TI-92 Plus: Appendix A (US English) Susan Gullord Revised: 02/23/01 1:48 PM Printed: 02/23/01 2:21 PM Page 450 of 132
FnOn [1] [, 2] ... [,99]
Selects the specified Y= functions for the
current graphing mode.
Note: In 3D graphing mode, only one
function at a time can be selected.
FnOn 2
selects
z2(x,y)
and deselects any previously
selected function. In the other graph modes,
previously selected functions are not
affected.
For
CATALOG
For var, low, high
[
, step
]
block
EndFor
Executes the statements in
block
iteratively
for each value of
var
, from
low
to
high
, in
increments of
step
.
var
must not be a system variable.
step
can be positive or negative. The default
value is 1.
block
can be either a single statement or a
series of statements separated with the “:”
character.
Program segment:
©
:0
!
tempsum :
1
!
step
:For i,
1
,
1
00,step
: tempsum+i
!
tempsum
:En
d
For
:Disp tempsum
©
Contents of
tempsum
after
execution:
5050
Contents of
tempsum
when
step
is changed to 2:
2500
format()
MATH/String menu
format(expression
[
, formatString
]
)
⇒
string
Returns
expression
as a character string based
on the format template.
expression
must simplify to a number.
formatString
is a string and must be in the
form: “
F
[
n
]
”, “
S[
n
]
”, “
E[
n
]
”, “
G[
n
][
c
]
”, where
[ ]
indicate optional portions.
F[
n
]
: Fixed format.
n
is the number of digits
to display after the decimal point.
S[
n
]
: Scientific format.
n
is the number of
digits to display after the decimal point.
E[
n
]
: Engineering format.
n
is the number of
digits after the first significant digit. The
exponent is adjusted to a multiple of three,
and the decimal point is moved to the right
by zero, one, or two digits.
format(1.234567,"f3")
¸
"
1
.235"
format(1.234567,"s2")
¸
"
1
.23
í
0"
format(1.234567,"e3")
¸
"
1
.235
í
0"
format(1.234567,"g3")
¸
"
1
.235"
format(1234.567,"g3")
¸
"
1
,234.567"
format(1.234567,"g3,r:")
¸
"
1
:235"
G[
n
][
c
]
: Same as fixed format but also
separates digits to the left of the radix into
groups of three.
c
specifies the group
separator character and defaults to a comma.
If
c
is a period, the radix will be shown as a
comma.
[R
c
]
: Any of the above specifiers may be
suffixed with the
R
c
radix flag, where
c
is a
single character that specifies what to
substitute for the radix point.