63
Example:
40 IF P=6 THEN PRINT "TRUE" ELSE PRINT "FALSE"
In this example, if P=6 the computer will print
TRUE
. Any other value will produce a
FALSE
.
In either case the computer will carry onto the next line.
It is possible for more than one statement to follow the
THEN
or
ELSE
command. A colon
separates the statements.
Example:
50 IF A =5 THEN PRINT "TRUE": S=S-3: GOTO 90 ELSE PRINT
"FALSE": K=K+8
So if A equals 5 the computer will print
TRUE
, subtract 3 from the variable S and go to
line 90. If A does not equal 5 the computer will print
FALSE
, add 8 to the variable K
and then carry on with the next normal line.
LOGICAL OPERATORS
Logical operators(IF...THEN...ELSE and such statements) are used where a condition is used
to determine subsequent operations within the user program. The logical operators are:
AND, OR,
and
NOT
.
For the purpose of this discussion, A and B are relational expressions having only TRUE
and FALSE. Logical operations are performed after mathematical and relational operations.
Operator
Example
Meaning
NOT
NOT A
If A is true, NOT A is false
AND
A AND B
A AND B have the value true, only if A and B are both ture.
A AND B have the value false if either A or B is false.
OR
A OR B
A OR B has the value true if either A or B or both are true.
It has the value false if both are false.
TRUTH TABLES
The following tables are called
TRUTH TABLES
. They illustrate the results of the previous
logical operations with both A and B given for every possible combination of values.
Summary of Contents for PreComputer Prestige
Page 1: ...COURSE BOOK...
