Rockwell Automation 57C610 Enhanced Basic Language, AutoMax - Manual (Page 56)

6Ć16
A loop can contain one or more loops provided that each inner loop
is completely contained within the outer loop. Using one loop within
another is called nesting. Each loop within a nest must contain its
own FOR and NEXT statements. The inner loop, the one that starts
first, must terminate before the outer loop, which must be completed
last. Loops cannot overlap.
The following are two legal nested loops:
10 FOR A%=1% TO 10% 10 FOR A%=1 TO 10
20 FOR B=2 TO 20 20 FOR B=2 TO 20
30 NEXT B 30 NEXT B
40 NEXT A% 40 FOR C%=3 TO 30
50 FOR D=4 TO 40
60 FOR E=5 TO 50
70 NEXT E
80 NEXT D
90 NEXT C%
100 NEXT A%
The following is a program with a legal nested loop:
10 PRINT I", J"
15 PRINT
20 FOR I%=1 TO 2
30 FOR J%=1 TO 3
35 !
40 PRINT I%,J%
45 !
50 NEXT J%
60 NEXT I%
70 END
Inside
Loop
Outside
Loop
Running the above program would display:
ăăĂĂĂĂI J
1 1
1 2
1 3
2 1
2 2
2 3
Inside
Loop
The following is an illegal nested loop because the inner loop does
not terminate first:
10 FOR M=1 TO 10
20 FOR N=2 TO 20
30 NEXT M
40 NEXT N
FOR and NEXT statements are commonly used to initialize arrays.
As illustrated in this example, line 5 defines a local array with 6 rows
and 11 columns. For more information, see section 6.1.1.
ă5 LOCAL X%(5,10)
10 FOR A%=1 TO 5