Texas Instruments TI-82 User Manual - Page 259

Accuracy Information

Page 259 highlights

Accuracy Information To maximize accuracy, the TI.82 carries more digits internally than it displays. Computational Accuracy Values in memory are stored using up to 14 digits with a 2-digit exponent. ¦ You can store a value in the WINDOW variables using up to 10 digits (12 digits for Xscl, Yscl, Tstep, and qstep). ¦ When a value is displayed, the displayed value is rounded as specified by the MODE setting (Chapter 1), with a maximum of 10 digits and a 2digit exponent. ¦ RegEQ displays up to 14 digits. Graphing Accuracy Xmin is the center of the leftmost pixel, Xmax is the center of the next to the right-most pixel. (The right-most pixel is reserved for the busy indicator.) @X is the distance between the centers of two adjacent pixels. ¦ @X is calculated as (XmaxNXmin)à94. ¦ If @X is entered from the Home screen or a program, then Xmax is calculated as [email protected]. Ymin is the center of the next to the bottom pixel, Ymax is the center of the top pixel. @Y is the distance between the centers of two adjacent pixels. ¦ @Y is calculated as (YmaxNYmin)à62. ¦ If @Y is entered from the Home screen or a program, then Ymax is calculated as [email protected]. Cursor coordinates are displayed as eight characters (which may include a negative sign, decimal point, and exponent). The values of X and Y are updated with a maximum of eight-digit accuracy. minimum, maximum, and intersect on the CALCULATE menu are calculated with a tolerance of 1EL5; dy/dx and ‰f(x)dx use a tolerance of 1EL3. Therefore, the result displayed may not be accurate to all eight displayed digits. (In general, for most functions, there are at least 5 accurate digits.) The tolerance can be specified for the command-line functions fMin(, fMax(, and fnInt( on the MATH MATH menu. Reference Information B-5

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Reference Information
B-5
Accuracy Information
To maximize accuracy, the TI
.
82 carries more digits internally than it displays.
Computational Accuracy
Values in memory are stored using up to 14 digits with a 2-digit exponent.
¦
You can store a value in the
WINDOW
variables using up to 10 digits (12
digits for
Xscl
,
Yscl
,
Tstep
, and
q
step
).
¦
When a value is displayed, the displayed value is rounded as specified
by the
MODE
setting (Chapter 1), with a maximum of 10 digits and a 2-
digit exponent.
¦
RegEQ
displays up to 14 digits.
Graphing Accuracy
Xmin
is the center of the leftmost pixel,
Xmax
is the center of the next to
the right-most pixel. (The right-most pixel is reserved for the busy
indicator.)
@
X
is the distance between the centers of two adjacent pixels.
¦
@
X
is calculated as (
Xmax
N
Xmin
)
à
94
.
¦
If
@
X
is entered from the Home screen or a program, then
Xmax
is
calculated as
Xmin+
@
X
94
.
Ymin
is the center of the next to the bottom pixel,
Ymax
is the center of the
top pixel.
@
Y
is the distance between the centers of two adjacent pixels.
¦
@
Y
is calculated as (
Ymax
N
Ymin
)
à
62
.
¦
If
@
Y
is entered from the Home screen or a program, then
Ymax
is
calculated as
Ymin+
@
Y
62
.
Cursor coordinates are displayed as eight characters (which may include a
negative sign, decimal point, and exponent). The values of
X
and
Y
are
updated with a maximum of eight-digit accuracy.
minimum
,
maximum
, and
intersect
on the
CALCULATE
menu are
calculated with a tolerance of 1
E
L
5;
dy/dx
and
f(x)dx
use a tolerance of
1
E
L
3. Therefore, the result displayed may not be accurate to all eight
displayed digits. (In general, for most functions, there are at least
5 accurate digits.) The tolerance can be specified for the command-line
functions
fMin(
,
fMax(
, and
fnInt(
on the
MATH MATH
menu.