Commands and Statements |
If the TO expression is larger than the starting expression and the step expression is negative then the loop will not execute. Similarly, if the TO expression is less than the starting expression and the STEP expression is positive, then the loop will not execute. After the conclusion of the loop, variable A contains the first value not us- ed in the loop.
Control cannot be passed to a statement within a FOR ... NEXT loop with GO TO, GO SUB etc, but a GO TO can be used to jump out of a FOR ... NEXT loop. FOR ... NEXT loops may be nested so long as each inner loop is completely contained in all outer loop~, and they employ different index variables.
If possible, integer index variables should be used to speed execution. Double preci- sion index variables are not allowed.
FOR variable=expression TO expression [STEP expression]
10FOR A = 1 TO 5
20PRINT A* A,
30NEXT A
40 END
RUN
1 4 9 16 25
GET
The GET statement reads the specified sector from the specified file into 128- byte random buffer. The file must be open for random access. If the sector number is not specIfied, the sector number of the previous GET or PUT is incremented and this sector is read. A GET without a sector number immediately after a file is opened will return the first sector. The largest possible sector number is 2046. If the GET com- mand is issued for a sector that has not yet been written, buffer contents are undefined, and there is no error message. However, if no greater record has ever been PUT or GET, the file will be extended.
GET [I] file number [,record number]
10OPEN "R" ,#3, "F1 :PERSON" 20GET#3,1
30FIELD #3, 20 AS N$, 9 AS SS$
40 PRINT N$,SS$
RUN
JONES, JOHN J. | 517317010 |
Ok
GOSUB
The GOSUB statement transfers program control to the line number specified as an argument. This line number is typically the first line number of a subroutine that is used several times during a program. The RETURN statement transfers control back to the first instruction that follows the last GOSUB statement executed.
GOSUB line number
10 lNPUT A
20IF A>O THEN GOSUB 100 ELSE PRINT "A MUST BE >0"
30GOTO 10
100PRINT SQR(AO);SIN(A);TAN(A)
110RETURN
