Logical Expressions - Sharp PC-1403 Operation Manual

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of B
Note: Value of A and B must be 0 (false) or 1 (true}.
True
False
True
False
True
False
True
False
Value
Value of A
AXOR B
of B
True False
True True True
False True False
Value
True
False
True
True
False
False
False False
Value
of B
Value of A
AOR B Value of A
AAND B
Relational expressions evaluate to eitherTrue or False. The computer represents True
by a 1; False is represented by a 0. In any logical test, an expression which evaluates
to 1 or more will be regarded as True, whereas one which evaluates to O or less will be
considered False. Good programming practice, however, di c tates the use of an
explicit relational expression instead of relying on this coinci d ence.
Logical Expressions
Logical expressions are relational expressions which use operators AND, OR,
XOR, and NOT. AND, OR, and XOR are used to connect two relational expres-
sions; the values of the combined expressions are as shown in the following tables.
"ABCOEF" = "ABCDEF"
"ABCOEF"
<>
"ABCDE"
"ABCDEF"
>
"ABCDE"
A<B
C(1,2)>;: 5
0(3)<>8
If A was equal to 1 O, B equal to 12, C(1,2) equal to 6, and 0(3) equal to 9, all of
these relational expressions would be True.
Chapter strings can also be compared in relational expressions. The two strings are
compared character by character according to their ASCII value starting at the first
character (see Appendix B for ASCII values). If one string is shorter than the other, a
o
or NUL will be used for any missing positions. All of the following relational
expressions are True:
The following are valid relational expressions:
Concepts and Terms of BASIC