HP 9g, Руководство пользователя

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E-28
⇒
Each program needs an END command to mark the end of the
program. This is displayed automatically when you create a new
program.
Increment and decrement
Post-fixed: Memory va + or Memory variable – –
Pre-fixed: +
+ Memory variable or – – Memory variable
⇒
A memory variable is decreased or increased by one. For standard
memory variables, the + + ( Increment ) and – – ( Decrement ) operators
can be either post-fixed or pre-fixed. For array variables, the operators
must be pre-fixed.
With pre-fixed operators, the memory variable is computed before the
expression is evaluated; with post-fixed operators, the memory variable
is computed after the expression is evaluated.
For loop
FOR
( start condition; continue condition; re-evaluation ) { statements }
⇒
A FOR loop is useful for repeating a set of similar actions while a
specified counter is between certain values.
For example:
FOR
( A = 1 ; A ≤ 4 ; A + + )
{ C = 3
×
A ; PRINT ” ANS = ” , C }
END
⇒
Result : ANS = 3, ANS = 6, ANS = 9, ANS = 12
The processing in this example is:
1.
FOR A = 1 : This initializes the value of A to 1 . Since A = 1 is consistent
with A
≤
4 , the statements are executed and A is incremented by 1.
2. Now A = 2 . This is consistent with A ≤ 4 , so the statements are
executed and A is again incremented by 1. And so on.
3. When A = 5 , it is no longer true that A
≤
4 , so statements are not
executed. The program then moves on to the next block of code.
Sleep command
SLEEP (
time
)
⇒
A SLEEP command suspends program execution for a specified time
(up to a maximum of 105 seconds). This is useful for displaying
intermediate results before resuming execution.
Swap command
SWAP (
memory variable A, memory variable B
)