Texas Instruments TITANIUM TI-89 - Manual (Page 862)

862 Appendix A: Functions and Instructions
randMat() MATH/Probability menu
randMat( numRows , numColumns )
⇒ ⇒ ⇒ ⇒ matrix
Returns a matrix of integers between -9 and 9 of
the specified dimension.
Both arguments must simplify to integers.
RandSeed 1147 ¸ Done
randMat(3,3) ¸





 8 л 3 6
л
2 3 л 6
0 4 л 6
Note: The values in this matrix will change
each time you press ¸.
randNorm() MATH/Probability menu
randNorm( mean , sd )
⇒ ⇒ ⇒ ⇒ expression
Returns a decimal number from the specific
normal distribution. It could be any real number
but will be heavily concentrated in the interval
[
mean -3ù sd , mean +3ù sd ].
RandSeed 1147 ¸ Done
randNorm(0,1) ¸ .492 ...
randNorm(3,4.5)
¸ ì
3.543
...
randPoly() MATH/Probability menu
randPoly( var , order )
⇒ ⇒ ⇒ ⇒ expression
Returns a polynomial in var of the specified order.
The coefficients are random integers in the range
ë 9 through 9. The leading coefficient will not be
zero.
order must be 0–99.
RandSeed 1147
¸
Done
randPoly(x,5) ¸
л 2ш x 5 +3ø x 4 м 6ш x 3 +4ø xì 6
RandSeed
MATH/Probability menu
RandSeed number
If number = 0, sets the seeds to the factory
defaults for the random-number generator. If
number ƒ 0, it is used to generate two seeds,
which are stored in system variables seed1
and seed2 .
RandSeed 1147 ¸ Done
rand() ¸ .158 ...
RclGDB CATALOG
RclGDB GDBvar
Restores all the settings stored in the Graph
database variable
GDBvar .
For a listing of the settings, see StoGDB .
Note: It is necessary to have something saved in
GDBvar before you can restore it.
RclGDB GDBvar ¸ Done
RclPic CATALOG
RclPic picVar [, row , column ]
Displays the Graph screen and adds the picture
stored in
picVar at the upper left-hand corner pixel
coordinates ( row , column ) using OR logic.
picVar must be a picture data type.
Default coordinates are (0, 0).
real() MATH/Complex menu
real( expression1 ) ⇒ ⇒ ⇒ ⇒ expression
Returns the real part of the argument.
Note: All undefined variables are treated as real
variables. See also
imag() .
real(2+3 i ) ¸ 2
real(z) ¸ z
real(x+iy) ¸ x