Texas Instruments TITANIUM TI-89 - Manual (Page 810)

810 Appendix A: Functions and Instructions
diag() MATH/Matrix menu
diag( list )
⇒ ⇒ ⇒ ⇒ matrix
diag( rowMatrix ) ⇒ ⇒ ⇒ ⇒ matrix
diag( columnMatrix )
⇒ ⇒ ⇒ ⇒ matrix
Returns a matrix with the values in the argument
list or matrix in its main diagonal.
diag({2,4,6})
¸





 2 0 0
0 4 0
0 0 6
diag( squareMatrix )
⇒ ⇒ ⇒ ⇒ rowMatrix
Returns a row matrix containing the elements
from the main diagonal of
squareMatrix .
squareMatrix must be square.
[4,6,8;1,2,3;5,7,9] ¸





 4 6 8
1 2 3
5 7 9
diag(ans(1)) ¸ [4 2 9]
Dialog CATALOG
Dialog
block
EndDlog
Generates a dialog box when the program is
executed.
block can be either a single statement or a series
of statements separated with the “:” character.
Valid
block options in the … I/O, 1:Dialog menu
item in the Program Editor are 1:Text , 2:Request,
4:DropDown , and 7:Title .
The variables in a dialog box can be given values
that will be displayed as the default (or initial)
value. If ¸ is pressed, the variables are
updated from the dialog box and variable
ok is
set to 1 . If N is pressed, its variables are not
updated, and system variable ok is set to zero.
Program listing:
:Dlogtest()
:Prgm
:Dialog
:Title "This is a dialog box"
:Request "Your name",Str1
:Dropdown "Month you were born",
seq(string(i),i,1,12),Var1
:EndDlog
:EndPrgm
dim() MATH/Matrix/Dimensions menu
dim( list )
⇒ ⇒ ⇒ ⇒ integer
Returns the dimension of list .
dim({0,1,2}) ¸ 3
dim( matrix )
⇒ ⇒ ⇒ ⇒ list
Returns the dimensions of matrix as a two-
element list {rows, columns}.
dim([1,л 1,2;л 2,3,5]) ¸ {2 3}
dim( string )
⇒ ⇒ ⇒ ⇒ integer
Returns the number of characters contained in
character string
string .
dim("Hello") ¸ 5
dim("Hello"&" there") ¸ 11