HP 49g+, Руководство пользователя, Страница: 689 / 862

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statement can be true (represented by the numerical value of 1. in the
calculator), or false (represented by the numerical value of 0. in the calculator).
The relational operators available for programming the calculator are:
____________________________________________________
Operator Meaning Example
____________________________________________________
== “is equal to” ‘x==2’
≠
“is not equal to” ‘3
≠
2’
< “is less than” ‘m<n’
> “is greater than” ‘10>a’
≥
“is greater than or equal to” ‘p
≥
q’
≤
“is less than or equal to” ‘7
≤
12’
_____________________________________________________
All of the operators, except == (which can be created by typing
‚Å
‚Å
), are available in the keyboard. They are also available in
„°
@)TEST@
.
Two numbers, variables, or algebraics connected by a relational operator
form a logical expression that can take value of true (1.), false (0.), or could
simply not be evaluated. To determine whether a logical statement is true or
not, place the statement in stack level 1, and press EVAL (
µ
). Examples:
‘2<10’
µ
, result: 1. (true)
‘2>10’
µ
, result: 0. (false)
In the next example it is assumed that the variable m is not initialized (it has
not been given a numerical value):
‘2==m’
µ
, result: ‘2==m’
The fact that the result from evaluating the statement is the same original
statement indicates that the statement cannot be evaluated uniquely.
Logical operators
Logical operators are logical particles that are used to join or modify simple
logical statements. The logical operators available in the calculator can be
easily accessed through the keystroke sequence:
„°
@)TEST@
L
.