HP Fortran Programmer's Reference

EXIT
20 i = 20
GO TO 100
30 i = 30
GO TO 100
40 i = 40
100 print *, i
END DO
Unconditional GO TO statement
Execution control
Flow control statements
The unconditional GO TO statement transfers control to the statement with the specified label.
Syntax
GO TO label
Execution logic
Control transfers to the statement at label.
Example
Older, “dusty-deck” Fortran programs often combine the GO TO statement with the logical IF
statement to form a kind of leap-frog logic, as in the following:
IF ( num1 /= num2) GO TO 10
PRINT *, ”num1 and num2 are equal.”
GO TO 30
10 IF ( num1 > num2 ) GO TO 20
PRINT *, ”num1 is smaller than num2.”
GO TO 30
20 PRINT *, ”num1 is greater than num2.”
30 CONTINUE
Arithmetic IF statement
The arithmetic IF transfers control to one of three labeled statements, as determined by the
value of an arithmetic expression.
Syntax
IF ( arithmetic-expression ) label1, label2, label3
Execution logic
1. arithmetic-expression is evaluated.
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