Texas Instruments Titanium TI-89, User Manual

Page: 627 / 977

Programming 624
Example 4
This example uses built-in functions to calculate the result without using a loop.
Ê
Prompts for input on Program I/O.
Ë
Calculates sum.
Ì
Displays output on Program I/O screen.
Note:
Because
Input
returns
n
as a number, you do not need to use
expr
to convert
n
.
Ê
Ë
Ì
:prog4()
:Prgm
:Input "Enter an integer",n
:sum(seq(i,i,1,n))
!
temp
:Disp temp
:EndPrgm
Function Used in this example to:
seq Generate the sequence of integers from 1 to n .
sum Sum the integers in the list generated by seq .
seq( expression
,
var
,
low
,
high
[,
step
]
)
Ê
expression used to generate the sequence
Ë
variable that will be incremented
Ì
initial and final values of
var
Í
increment for var ; if omitted, uses 1
Ê Ë Ì Ì Í